Funding, Deals & Partnerships: BIOLOGICS & MEDICAL DEVICES; BioMed e-Series; Medicine and Life Sciences Scientific Journal – http://PharmaceuticalIntelligence.com
Reporter and Curator: Mr. Srinjoy Chakraborty (Junior Research Felllow) and Dr. Sudipta Saha, Ph.D.
Coronavirus disease 2019 (COVID-19), which is caused by the novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has emerged as a serious global health issue with high transmission rates affecting millions of people worldwide. The SARS-CoV-2 is known to damage cells in the respiratory system, thus causing viral pneumonia. The novel SARS-CoV-2 is a close relative to the previously identified severe acute respiratory syndrome-coronavirus (SARS-CoV) and Middle East respiratory syndrome-coronavirus (MERS-CoV) which affected several people in 2002 and 2012, respectively. Ever since the outbreak of covid-19, several reports have poured in about the impact of Covid-19 on pregnancy. A few studies have highlighted the impact of the viral infection in pregnant women and how they are more susceptible to the infection because of the various physiological changes of the cardiopulmonary and immune systems during pregnancy. It is known that SARS-CoV and MERS-CoV diseases have influenced the fatality rate among pregnant women. However, there are limited studies on the impact of the novel corona virus on the course and outcome of pregnancy.
Figure: commonly observed clinical symptoms of COVID-19 in the general population: Fever and cough, along with dyspnoea, diarrhoea, and malaise are the most commonly observed symptoms in pregnant women, which is similar to that observed in the normal population.
The WHO and the Indian Council of Medical Research (ICMR) have proposed detailed guidelines for treating pregnant women; these guidelines must be strictly followed by the pregnant individual and their families. According to the guidelines issued by the ICMR, the risk of pregnant women contracting the virus to that of the general population. However, the immune system and the body’s response to a viral infection is altered during pregnancy. This may result in the manifestation of more severe symptoms. The ICMR guidelines also state that the reported cases of COVID-19 pneumonia in pregnancy are milder and with good recovery. However, by observing the trends of the other coronavirus infection (SARS, MERS), the risks to the mother appear to increase in particular during the last trimester of pregnancy. Cases of preterm birth in women with COVID-19 have been mentioned in a few case report, but it is unclear whether the preterm birth was always iatrogenic, or whether some were spontaneous. Pregnant women with heart disease are at highest risk of acquiring the infection, which is similar to that observed in the normal population. Most importantly, the ICMR guidelines highlights the impact of the coronavirus epidemic on the mental health of pregnant women. It mentions that the since the pandemic has begun, there has been an increase in the risk of perinatal anxiety and depression, as well as domestic violence. It is critically important that support for women and families is strengthened as far as possible; that women are asked about mental health at every contact.
With the available literature available on the impact of SARS and MERS on reproductive outcome, it has been mentioned that SARS infection did increase the risk of miscarriage, preterm birth and, intrauterine foetal growth restriction. However, the same has not been demonstrated in early reports from COVID-19 infection in pregnancy. According to a study that included 8200 participants conducted by the centre for disease control and prevention, pregnant women may be at a higher risk of acquiring severe infection and need for ICU admissions as compared to their non-pregnant counterparts. However, a detailed and thorough study involving a larger proportion of the population is needed today.
Reporter and Original Article Co-Author: Amandeep Kaur, B.Sc. , M.Sc.
Abstract Since its inception in late 2019, SARS-CoV-2 has evolved resulting in emergence of various variants in different countries. These variants have spread worldwide resulting in devastating second wave of COVID-19 pandemic in many countries including India since the beginning of 2021. To control this pandemic continuous mutational surveillance and genomic epidemiology of circulating strains is very important. In this study, we performed mutational analysis of the protein coding genes of SARS-CoV-2 strains (n=2000) collected during January 2021 to March 2021. Our data revealed the emergence of a new variant in West Bengal, India, which is characterized by the presence of 11 co-existing mutations including D614G, P681H and V1230L in S-glycoprotein. This new variant was identified in 70 out of 412 sequences submitted from West Bengal. Interestingly, among these 70 sequences, 16 sequences also harbored E484K in the S glycoprotein. Phylogenetic analysis revealed strains of this new variant emerged from GR clade (B.1.1) and formed a new cluster. We propose to name this variant as GRL or lineage B.1.1/S:V1230L due to the presence of V1230L in S glycoprotein along with GR clade specific mutations. Co-occurrence of P681H, previously observed in UK variant, and E484K, previously observed in South African variant and California variant, demonstrates the convergent evolution of SARS-CoV-2 mutation. V1230L, present within the transmembrane domain of S2 subunit of S glycoprotein, has not yet been reported from any country. Substitution of valine with more hydrophobic amino acid leucine at position 1230 of the transmembrane domain, having role in S protein binding to the viral envelope, could strengthen the interaction of S protein with the viral envelope and also increase the deposition of S protein to the viral envelope, and thus positively regulate virus infection. P618H and E484K mutation have already been demonstrated in favor of increased infectivity and immune invasion respectively. Therefore, the new variant having G614G, P618H, P1230L and E484K is expected to have better infectivity, transmissibility and immune invasion characteristics, which may pose additional threat along with B.1.617 in the ongoing COVID-19 pandemic in India.
Study: Emergence of a new SARS-CoV-2 variant from GR clade with a novel S glycoprotein mutation V1230L in West Bengal, India
Nir Hacohen and Marcia Goldberg, Researchers at MGH and the Broad Institute identify protein “signature” of severe COVID-19
Curator and Reporter: Aviva Lev-Ari, PhD, RN
Longitudinal proteomic analysis of plasma from patients with severe COVID-19 reveal patient survival-associated signatures, tissue-specific cell death, and cell-cell interactions
16% of COVID-19 patients display an atypical low-inflammatory plasma proteome
Severe COVID-19 is associated with heterogeneous plasma proteomic responses
Death of virus-infected lung epithelial cells is a key feature of severe disease
Lung monocyte/macrophages drive T cell activation, together promoting epithelial damage
Summary
Mechanisms underlying severe COVID-19 disease remain poorly understood. We analyze several thousand plasma proteins longitudinally in 306 COVID-19 patients and 78 symptomatic controls, uncovering immune and non-immune proteins linked to COVID-19. Deconvolution of our plasma proteome data using published scRNAseq datasets reveals contributions from circulating immune and tissue cells. Sixteen percent of patients display reduced inflammation yet comparably poor outcomes. Comparison of patients who died to severely ill survivors identifies dynamic immune cell-derived and tissue-associated proteins associated with survival, including exocrine pancreatic proteases. Using derived tissue-specific and cell type-specific intracellular death signatures, cellular ACE2 expression, and our data, we infer whether organ damage resulted from direct or indirect effects of infection. We propose a model in which interactions among myeloid, epithelial, and T cells drive tissue damage. These datasets provide important insights and a rich resource for analysis of mechanisms of severe COVID-19 disease.
The quest to identify mechanisms that might be contributing to death in COVID-19: Why do some patients die from this disease, while others — who appear to be just as ill do not?
Researchers at Massachusetts General Hospital (MGH) and the Broad Institute of MIT and Harvard have identified the protein “signature” of severe COVID-19
Interest was to develop methods for studying human immune responses to infections, which they had applied to the condition known as bacterial sepsis. The three agreed to tackle this new problem with the goal of understanding how the human immune system responds to SARS-CoV-2, the novel pathogen that causes COVID-19.
How scientists launched a study in days to probe COVID-19’s unpredictability
Collecting these specimens required a large team of collaborators from many departments, which worked overtime for five weeks to amass blood samples from 306 patients who tested positive for COVID-19, as well as from 78 patients with similar symptoms who tested negative for the coronavirus.
Credit : Alexandra-Chloé VillaniResearch associates at Mass General who worked countless hours to process blood samples for the COVID Acute Cohort Study (from left to right: Anna Gonye, Irena Gushterova, and Tom Lasalle)By Leah Eisenstadt
As the COVID-19 surge began in March, Mass General and Broad researchers worked around the clock to begin learning why some patients fare worse with the disease than others
The study found that most patients with COVID-19 have a consistent protein signature, regardless of disease severity; as would be expected, their bodies mount an immune response by producing proteins that attack the virus. “But we also found a small subset of patients with the disease who did not demonstrate the pro-inflammatory response that is typical of other COVID-19 patients,” Filbin said, yet these patients were just as likely as others to have severe disease. Filbin, who is also an assistant professor of emergency medicine at Harvard Medical School (HMS), noted that patients in this subset tended to be older people with chronic diseases, who likely had weakened immune systems.
Among other revelations, this showed that the most prevalent severity-associated protein, a pro-inflammatory protein called interleukin-6 (IL-6) rose steadily in patients who died, while it rose and then dropped in those with severe disease who survived. Early attempts by other groups to treat COVID-19 patients experiencing acute respiratory distress with drugs that block IL-6 were disappointing, though more recent studies show promise in combining these medications with the steroid dexamethasone.
Hacohen, who is a professor of medicine at HMS and director of the Broad’s Cell Circuits Program:
“You can ask which of the many thousands of proteins that are circulating in your blood are associated with the actual outcome,” he said, “and whether there is a set of proteins that tell us something.”
Goldberg, who is a professor of emergency medicine at HMS:
They are highly likely to be useful in figuring out some of the underlying mechanisms that lead to severe disease and death in COVID-19,” she said, noting her gratitude to the patients involved in the study. Their samples are already being used to study other aspects of COVID-19, such as identifying the qualities of antibodies that patients form against the virus.
Thriving Vaccines and Research: Weizmann Institute Coronavirus Research Development
Reporter:Amandeep Kaur, B.Sc., M.Sc.
In early February, Prof. Eran Segal updated in one of his tweets and mentioned that “We say with caution, the magic has started.”
The article reported that this statement by Prof. Segal was due to decreasing cases of COVID-19, severe infection cases and hospitalization of patients by rapid vaccination process throughout Israel. Prof. Segal emphasizes in another tweet to remain cautious over the country and informed that there is a long way to cover and searching for scientific solutions.
A daylong webinar entitled “COVID-19: The epidemic that rattles the world” was a great initiative by Weizmann Institute to share their scientific knowledge about the infection among the Israeli institutions and scientists. Prof. Gideon Schreiber and Dr. Ron Diskin organized the event with the support of the Weizmann Coronavirus Response Fund and Israel Society for Biochemistry and Molecular Biology. The speakers were invited from the Hebrew University of Jerusalem, Tel-Aviv University, the Israel Institute for Biological Research (IIBR), and Kaplan Medical Center who addressed the molecular structure and infection biology of the virus, treatments and medications for COVID-19, and the positive and negative effect of the pandemic.
The article reported that with the emergence of pandemic, the scientists at Weizmann started more than 60 projects to explore the virus from different range of perspectives. With the help of funds raised by communities worldwide for the Weizmann Coronavirus Response Fund supported scientists and investigators to elucidate the chemistry, physics and biology behind SARS-CoV-2 infection.
Prof. Avi Levy, the coordinator of the Weizmann Institute’s coronavirus research efforts, mentioned “The vaccines are here, and they will drastically reduce infection rates. But the coronavirus can mutate, and there are many similar infectious diseases out there to be dealt with. All of this research is critical to understanding all sorts of viruses and to preempting any future pandemics.”
The following are few important projects with recent updates reported in the article.
Mapping a hijacker’s methods
Dr. Noam Stern-Ginossar studied the virus invading strategies into the healthy cells and hijack the cell’s systems to divide and reproduce. The article reported that viruses take over the genetic translation system and mainly the ribosomes to produce viral proteins. Dr. Noam used a novel approach known as ‘ribosome profiling’ as her research objective and create a map to locate the translational events taking place inside the viral genome, which further maps the full repertoire of viral proteins produced inside the host.
She and her team members grouped together with the Weizmann’s de Botton Institute and researchers at IIBR for Protein Profiling and understanding the hijacking instructions of coronavirus and developing tools for treatment and therapies. Scientists generated a high-resolution map of the coding regions in the SARS-CoV-2 genome using ribosome-profiling techniques, which allowed researchers to quantify the expression of vital zones along the virus genome that regulates the translation of viral proteins. The study published in Nature in January, explains the hijacking process and reported that virus produces more instruction in the form of viral mRNA than the host and thus dominates the translation process of the host cell. Researchers also clarified that it is the misconception that virus forced the host cell to translate its viral mRNA more efficiently than the host’s own translation, rather high level of viral translation instructions causes hijacking. This study provides valuable insights for the development of effective vaccines and drugs against the COVID-19 infection.
Like chutzpah, some things don’t translate
Prof. Igor Ulitsky and his team worked on untranslated region of viral genome. The article reported that “Not all the parts of viral transcript is translated into protein- rather play some important role in protein production and infection which is unknown.” This region may affect the molecular environment of the translated zones. The Ulitsky group researched to characterize that how the genetic sequence of regions that do not translate into proteins directly or indirectly affect the stability and efficiency of the translating sequences.
Initially, scientists created the library of about 6,000 regions of untranslated sequences to further study their functions. In collaboration with Dr. Noam Stern-Ginossar’s lab, the researchers of Ulitsky’s team worked on Nsp1 protein and focused on the mechanism that how such regions affect the Nsp1 protein production which in turn enhances the virulence. The researchers generated a new alternative and more authentic protocol after solving some technical difficulties which included infecting cells with variants from initial library. Within few months, the researchers are expecting to obtain a more detailed map of how the stability of Nsp1 protein production is getting affected by specific sequences of the untranslated regions.
The landscape of elimination
The article reported that the body’s immune system consists of two main factors- HLA (Human Leukocyte antigen) molecules and T cells for identifying and fighting infections. HLA molecules are protein molecules present on the cell surface and bring fragments of peptide to the surface from inside the infected cell. These peptide fragments are recognized and destroyed by the T cells of the immune system. Samuels’ group tried to find out the answer to the question that how does the body’s surveillance system recognizes the appropriate peptide derived from virus and destroy it. They isolated and analyzed the ‘HLA peptidome’- the complete set of peptides bound to the HLA proteins from inside the SARS-CoV-2 infected cells.
After the analysis of infected cells, they found 26 class-I and 36 class-II HLA peptides, which are present in 99% of the population around the world. Two peptides from HLA class-I were commonly present on the cell surface and two other peptides were derived from coronavirus rare proteins- which mean that these specific coronavirus peptides were marked for easy detection. Among the identified peptides, two peptides were novel discoveries and seven others were shown to induce an immune response earlier. These results from the study will help to develop new vaccines against new coronavirus mutation variants.
Gearing up ‘chain terminators’ to battle the coronavirus
Prof. Rotem Sorek and his lab discovered a family of enzymes within bacteria that produce novel antiviral molecules. These small molecules manufactured by bacteria act as ‘chain terminators’ to fight against the virus invading the bacteria. The study published in Nature in January which reported that these molecules cause a chemical reaction that halts the virus’s replication ability. These new molecules are modified derivates of nucleotide which integrates at the molecular level in the virus and obstruct the works.
Prof. Sorek and his group hypothesize that these new particles could serve as a potential antiviral drug based on the mechanism of chain termination utilized in antiviral drugs used recently in the clinical treatments. Yeda Research and Development has certified these small novel molecules to a company for testing its antiviral mechanism against SARS-CoV-2 infection. Such novel discoveries provide evidences that bacterial immune system is a potential repository of many natural antiviral particles.
Resolving borderline diagnoses
Currently, Real-time Polymerase chain reaction (RT-PCR) is the only choice and extensively used for diagnosis of COVID-19 patients around the globe. Beside its benefits, there are problems associated with RT-PCR, false negative and false positive results and its limitation in detecting new mutations in the virus and emerging variants in the population worldwide. Prof. Eran Elinavs’ lab and Prof. Ido Amits’ lab are working collaboratively to develop a massively parallel, next-generation sequencing technique that tests more effectively and precisely as compared to RT-PCR. This technique can characterize the emerging mutations in SARS-CoV-2, co-occurring viral, bacterial and fungal infections and response patterns in human.
The scientists identified viral variants and distinctive host signatures that help to differentiate infected individuals from non-infected individuals and patients with mild symptoms and severe symptoms.
In Hadassah-Hebrew University Medical Center, Profs. Elinav and Amit are performing trails of the pipeline to test the accuracy in borderline cases, where RT-PCR shows ambiguous or incorrect results. For proper diagnosis and patient stratification, researchers calibrated their severity-prediction matrix. Collectively, scientists are putting efforts to develop a reliable system that resolves borderline cases of RT-PCR and identify new virus variants with known and new mutations, and uses data from human host to classify patients who are needed of close observation and extensive treatment from those who have mild complications and can be managed conservatively.
Moon shot consortium refining drug options
The ‘Moon shot’ consortium was launched almost a year ago with an initiative to develop a novel antiviral drug against SARS-CoV-2 and was led by Dr. Nir London of the Department of Chemical and Structural Biology at Weizmann, Prof. Frank von Delft of Oxford University and the UK’s Diamond Light Source synchroton facility.
To advance the series of novel molecules from conception to evidence of antiviral activity, the scientists have gathered support, guidance, expertise and resources from researchers around the world within a year. The article reported that researchers have built an alternative template for drug-discovery, full transparency process, which avoids the hindrance of intellectual property and red tape.
The new molecules discovered by scientists inhibit a protease, a SARS-CoV-2 protein playing important role in virus replication. The team collaborated with the Israel Institute of Biological Research and other several labs across the globe to demonstrate the efficacy of molecules not only in-vitro as well as in analysis against live virus.
Further research is performed including assaying of safety and efficacy of these potential drugs in living models. The first trial on mice has been started in March. Beside this, additional drugs are optimized and nominated for preclinical testing as candidate drug.
Why wait for more info? A new case of cerebral sinus venus thrombosis was reported in a 25 year old man who became critically ill from a cerebral hemorrhage. And for women age 20-50, CSVT occurred in 1 in 13,000, or 4-15X higher than background.
UPDATED on 4/14/2021
How UK doctor linked rare blood-clotting to AstraZeneca Covid jab
We have put together the following mechanism for thrombosis including central vein sinus thrombosis as a complication of both J&J and the AstraZeneca vaccines. This unifying mechanism explains the predilection of cerebral veins and higher risk in younger women. Please share your thoughts on the proposed mechanism.
We have submitted the attached manuscript to SSRN. Sharing this promptly considering the public health significance.
Thanks
Figure 1. AstraZeneca or Janssen COVID-19 vaccine induced thromboinflammation and cerebral venous sinus thrombosis (CVST)-Proposed Mechanisms: Adenovirus carrier delivers SARS-CoV-2 DNA encoding the Spike (S) protein to the lung megakaryocytes via the coxsackie-adenovirus receptor (CAR). Spike protein induces COX-2 expression in megakaryocytes leading to megakaryocyte activation, biogenesis of activated platelets that express COX-2 and generate thromboxane A2 (TxA2). Cerebral vein sinus endothelial cells express podoplanin, a natural ligand for CLEC2 receptors on platelets. Platelets traversing through the cerebral vein sinuses would be further activated by TxA2 dependent podoplanin-CLEC2 signaling, leading to release of extracellular vesicles, thereby promoting CLEC5A and TLR2 mediated neutrophil activation, thromboinflammation, CVST, and thromboembolism in other vascular beds. Young age and female gender are associated with increased TxA2 generation and platelet activation respectively, and hence increased risk of thromboembolic complications following vaccination.
Best regards,
Ajay
Ajay Gupta, M.B.,B.S., M.D.
Clinical Professor,
Division of Nephrology, Hypertension and Kidney Transplantation
University of California Irvine
President & CSO, KARE Biosciences (www.karebio.com)
Title: SARS-CoV-2 vaccination induced thrombosis: Is chemoprophylaxis with antiplatelet agents warranted?
Guest Authors:
Kate Chander Chiang1
Ajay Gupta, MBBS, MD1,2
Affiliations
(1) KARE Biosciences, Orange, CA 92869
(2) Department of Medicine, University of California Irvine (UCI) School of Medicine, Orange, CA 92868
*Corresponding author:
Ajay Gupta, MBBS, MD
Clinical Professor of Medicine,
Division of Nephrology, Hypertension and Kidney Transplantation
University of California Irvine (UCI) School of Medicine,
Orange, CA 92868
Tel: +1 (562) 412-6259
E-mail: ajayg1@hs.uci.edu
Word Count
Abstract: 359
Main Body: 1,648
Funding: No funding was required.
Conflict of Interest: AG and KCC have filed a patent for use of Ramatroban as an anti-thrombotic and immune modulator in SARS-CoV-2 infection. The patents have been licensed to KARE Biosciences. KCC is an employee of KARE Biosciences.
Author Contributions: AG and KCC conceptualized, created the framework, wrote and reviewed the manuscript.
The COVID-19 vaccines, Vaxzevria® (AstraZeneca) and the Janssen vaccine (Johnson & Johnson) are highly effective but associated with rare thrombotic complications. These vaccines are comprised of recombinant, replication incompetent, chimpanzee adenoviral vectors encoding the Spike (S) glycoprotein of SARS-CoV-2. The adenovirus vector infects epithelial cells expressing the coxsackievirus and adenovirus receptor (CAR). The S glycoprotein of SARS-CoV-2 is expressed locally stimulating neutralizing antibody and cellular immune responses, which protect against COVID-19. The immune responses are highly effective in preventing symptomatic disease in adults irrespective of age, gender or ethnicity. However, both vaccines have been associated with thromboembolic events including cerebral venous sinus thrombosis (CVST). Megakaryocytes also express CAR, leading us to postulate adenovirus vector uptake and expression of spike glycoprotein by megakaryocytes. Spike glycoprotein induces expression of cyclooxygenase -2 (COX-2), leading to generation of thromboxane A2 (TxA2). TxA2 promotes megakaryocyte activation, biogenesis of activated platelets and thereby increased thrombogenicity. Cerebral vein sinus endothelial cells express podoplanin, a natural ligand for CLEC2 receptors on platelets. Platelets traversing through the cerebral vein sinuses would be further activated by TxA2 dependent podoplanin-CLEC2 signaling, leading to CVST. The mechanisms proposed are consistent with the following clinical observations. First, a massive increase in TxA2 generation promotes platelet activation and thromboinflammation in COVID-19 patients. Second, TxA2 generation and platelet activation is increased in healthy women compared to men, and in younger mice compared to older mice; and, younger age and female gender appear to be associated with increased risk of thromboembolism as a complication of adenoviral vector based COVID-19 vaccine. The roll out of both AstraZeneca and Janssen vaccines has been halted for adults under 30-60 years of age in many countries. We propose that antiplatelet agents targeting TxA2 receptor signaling should be considered for chemoprophylaxis when administering the adenovirus based COVID-19 vaccines to adults under 30-60 years of age. In many Asian and African countries, only adenovirus-based COVID-19 vaccines are available at present. A short course of an antiplatelet agent such as aspirin could allow millions to avail of the benefits of the AstraZeneca and Janssen COVID-19 vaccines which could be otherwise either denied to them or put them at undue risk of thromboembolic complications.
COVID-19 disease is caused by a novel positive-strand RNA coronavirus (SARS-CoV-2), which belongs to the Coronaviridae family, along with the severe acute respiratory syndrome (SARS) and the Middle East respiratory syndrome (MERS) coronaviruses.1 The genome of these viruses encodes several non-structural and structural proteins, including spike (S), envelope (E), membrane (M), and nucleocapsid (N) proteins.2 The majority of the vaccines for COVID-19 that employ administration of viral antigens or viral gene sequences aim to induce neutralizing antibodies against the viral spike protein (S), preventing uptake through the ACE2 receptor, and thereby blocking infection.3
The Janssen COVID-19 vaccine (Johnson & Johnson) is comprised of a recombinant, replication- incompetent Ad26 vector, encoding a stabilized variant of the SARS-CoV-2 Spike (S) protein. The ChAdOx1 nCoV-19 vaccine (AZD1222, Vaxzevria®) was developed at Oxford University and consists of a replication-deficient chimpanzee adenoviral vector ChAdOx1, encoding the S protein.4 In US Phase III trials, Vaxzevria has been demonstrated to have 79% efficacy at preventing symptomatic COVID-19, and 100% efficacy against severe or critical disease and hospitalization, with comparable efficacy across ethnicity, gender and age.5 However, Vaxzevria has been associated with thrombotic and embolic events including disseminated intravascular coagulation (DIC) and cerebral venous sinus thrombosis (CVST), occurring within 14 days after vaccination, mostly in people under 55 years of age, the majority of whom have been women.6 Data from Europe suggests that the event rate for thromboembolic events may be about 10 per million vaccinated. Antibodies to platelet factor 4/heparin complexes have been recently reported in a few patients.7 However, the significance of this finding remains to be established. As of April 12, 2021, about 6.8 million doses of the Janssen vaccine have been administered in the U.S.8 CDC and FDA are reviewing data involving six reported U.S. cases of CVST in combination with thrombocytopenia.8 All six cases occurred among women between the ages of 18 and 48, and symptoms occurred 6 to 13 days after vaccination.8
SARS-CoV-2 is known to cause thromboinflammation leading to thrombotic microangiopathy, pulmonary thrombosis, pedal acro-ischemia (“COVID-toes”), arterial clots, strokes, cardiomyopathy, coronary and systemic vasculitis, deep venous thrombosis, pulmonary embolism, and microvascular thrombosis in renal, cardiac and brain vasculature.9-14 Cerebral venous sinus thrombosis (CVST) has also been reported in COVID-19 patients.15 Amongst 34,331 hospitalized COVID-19 patients, CVST was diagnosed in 28.16 In a multicenter, multinational, cross sectional, retrospective study of 8 patients diagnosed with CVST and COVID-19, seven were women.17 In another series of 41 patients with COVID-19 and CVST, the average age was about 50 years (SD, 16.5 years).17 The pathobiology of thrombotic events associated with the AstraZeneca vaccine should be viewed in the context of mechanisms underlying thromboinflammation that complicates SARS-CoV-2 infection and COVID-19 disease.
A. Role of COX-2 and thromboxane A2 in thromboinflammation complicating adenovirus based COVID-19 vaccine encoding the Spike protein of SARS-CoV-2
Thromboinflammation in COVID-19 seems to be primarily caused by endothelial, platelet and neutrophil activation, platelet-neutrophil aggregates and release of neutrophil extracellular traps (NETs).13,18 Platelet activation in COVID-19 is fueled by a lipid storm characterized by massive increases in thromboxane A2 (TxA2) levels in the blood and bronchoalveolar lavage fluid.19,20 Cyclooxygenase (COX) enzymes catalyze the first step in the biosynthesis of TxA2 from arachidonic acid, and COX-2 expression is induced by the spike (S) protein of coronaviruses.21 We postulate that an aberrant increase in TxA2 generation induced by the spike protein expression from the AstraZeneca vaccine leads to thromboinflammation, thromboembolism and CVST. 4
The support for the above proposed mechanism comes from the following observations. First, when mice of different age groups were infected with SARS-CoV virus, the generation of TxA2 was markedly increased in younger mice compared to middle aged mice.22 Furthermore, in children with asymptomatic or mildly symptomatic SARS-CoV-2 infection, microvascular thrombosis and thrombotic microangiopathy occur early in infection.20 These observations are consistent with the higher risk for thrombosis in adults under 60 years of age, compared with the older age group.6,7 Second, platelets from female mice are much more reactive than from male mice.23 Furthermore, TxA2 generation, TxA2-platelet interaction and activation is increased in women compared to men.24,25 These observations are consistent with disproportionately increased risk of thrombosis in women following AstraZeneca and Janssen COVID-19 vaccines.
The adenoviral vector ChAdOx1, containing nCoV-19 spike protein gene, infects host cells through the coxsackievirus and adenovirus receptor (CAR).26 CAR-dependent cell entry of the viral vector allows insertion of the SARS-CoV-2 spike protein gene and expression of Spike protein by host cells (Figure 1). CAR is primarily expressed on epithelial tight junctions.27 CAR expression has also been reported in platelets,28 and since platelets are anucleate cells CAR expression by megakaryocytes can be inferred. Therefore, AstraZeneca and Janssen vaccines would be expected to induce expression of Spike protein in megakaryocytes and platelets (Figure 1).
Spike protein of coronaviruses in known to induce COX-2 gene expression.21,29 COX-2 expression is induced during normal human megakaryopoiesis and characterizes newly formed platelets.30 While in healthy controls <10% of circulating platelets express COX-2, in patients with high platelet generation, up to 60% of platelets express COX-2.30 Generation of TxA2 by platelets is markedly suppressed by COX-2 inhibition in patients with increased megakaryopoiesis versus healthy subjects.30 Therefore, we postulate that expression of Spike protein induces COX-2 expression and generation of thromboxane A2 by megakaryocytes. TxA2 promotes biogenesis of activated platelets expressing COX-2. Platelet TxA2 generation leads to platelet activation and aggregation, and thereby thromboinflammation (Figure 1).
Extravascular spaces of the lungs comprise populations of mature and immature megakaryocytes that originate from the bone marrow, such that lungs are a major site of platelet biogenesis, accounting for approximately 50% of total platelet production or about 10 million platelets per hour.31 More than 1 million extravascular megakaryocytes have been observed in each lung of transplant mice.31 Following intramuscular injection of the AstraZeneca and Janssen vaccines, the adenovirus vector will traverse the veins and lymphatics to be delivered to the pulmonary circulation thereby exposing lung megakaryocytes in the first pass. Interestingly, under thrombocytopenic conditions, haematopoietic progenitors migrate out of the lung to repopulate the bone marrow and completely reconstitute blood platelet counts.31
B. Predilection of cerebral venous sinuses for thrombosis following vaccination
Recent studies have demonstrated that arterial, venous and sinusoidal endothelial cells in the brain uniquely express markers of the lymphatic endothelium including podoplanin.32 Podoplanin serves as a ligand for CLEC2 receptors on platelets.33 Thromboxane A2 dependent CLEC2 signaling leads to platelet activation (Figure 1), while a TxA2 receptor antagonist nearly abolish CLEC2 signaling and platelet activation.33 TxA2 dependent CLEC2 signaling promotes release of exosomes and microvesicles from platelets, leading to activation of CLEC5A and TLR2 receptors respectively on neutrophils, neutrophil activation and release of neutrophil extracellular traps (NETs) (Figure 1).34 Neutrophil activation, more than platelet activation, is associated with thrombotic complications in COVID-19.13,18,35 As proposed above, the expression of podoplanin, a unique molecular signature of cerebral endothelial cells, may be responsible for the predilection of brain vascular bed to thromboinflammation and CVST as a complication of COVID-19 vaccines. 5
C. Chemoprophylaxis with antiplatelet agents
In animal models of endotoxin mediated endothelial injury and thromboinflammation, antagonism of TxA2 signaling prevents ARDS, reduces myocardial damage and increases survival.36-38
Considering the key role played by platelets in thromboinflammation, we propose consideration of antiplatelet agents, either aspirin or TxA2 receptor antagonists, as chemoprophylactic agents when the AstraZeneca vaccine is administered to adults between 18 and 60 years of age.39 High bleeding risk because of another medical condition or medication would be contraindications to use of antiplatelet agents.39 Medical conditions that increase bleeding risk include previous gastrointestinal bleeding, peptic ulcer disease, blood clotting problems, and kidney disease.39 Medications that increase bleeding risk include nonsteroidal anti-inflammatory drugs, steroids, and other anticoagulants or anti-platelet agents.39 Aspirin appears to be safe in COVID-19. In a retrospective observational study in hospitalized patients with COVID-19, low-dose aspirin was found to be effective in reducing morbidity and mortality; and was not associated with any safety issues including major bleeding.40 Therefore, aspirin is likely to be safe as an adjunct to COVID-19 vaccines even in the event of a subsequent infection with SARS-CoV-2 virus.
Can aspirin influence the host immune response to the COVID-19 vaccines? This issue merits further investigation. When healthy adults > 65 years of age were given influenza vaccine and randomized to receive 300 mg aspirin or placebo on days 1, 2, 3, 5 and 7, the aspirin group showed 4-fold or greater rise in influenza specific antibodies.41 The risk-benefit analysis, based on above information, suggests that a one to three week course of low-dose aspirin merits consideration in order to prevent the thromboembolic events associated with the AstraZeneca vaccine.
SUMMARY
Thromboembolic disease including disseminated intravascular coagulation and cerebral venous sinus thrombosis have been reported in association with AstraZeneca and Janssen COVID-19 vaccines. Many countries have halted use of these vaccines either entirely or for adults under 30 to 60 years of age. European and North American countries generally have access to mRNA vaccines. However, in Asian and African countries the choices are limited to adenovirus based COVID-19 vaccines. The governments in such countries are forging ahead with vaccinating all adults, including those under 60 years of age, with Vaxzevria, Covishield (the version of Vaxzevria manufactured by the Serum Institute of India) or the Janssen vaccines. This has led to grave concern and anxiety amongst the citizens and medical professionals. Considering the profound global public health implications of limiting the use of these vaccines, it is critical to understand the pathobiology of vaccination induced thrombotic events in order to guide strategies aimed at prevention. In this regard, studies are urgently needed to examine lipid mediators and thromboxane A2 – platelet axis following vaccination with these vaccines, compared with mRNA vaccines. The risk-benefit analysis based on information presented here suggests that chemoprophylaxis using a short course of low-dose aspirin in adults under 60 years of age may be justified in conjunction with adenovirus based COVID-19 vaccines in order to prevent thromboembolic events and enhance safety. 6
Figure 1. AstraZeneca or Janssen COVID-19 vaccine induced thromboinflammation and cerebral venous sinus thrombosis (CVST)-Proposed Mechanisms: Adenovirus carrier delivers SARS-CoV-2 DNA encoding the Spike (S) protein to the lung megakaryocytes via the coxsackie-adenovirus receptor (CAR). Spike protein induces COX-2 expression in megakaryocytes leading to megakaryocyte activation, biogenesis of activated platelets that express COX-2 and generate thromboxane A2 (TxA2). Cerebral vein sinus endothelial cells express podoplanin, a natural ligand for CLEC2 receptors on platelets. Platelets traversing through the cerebral vein sinuses would be further activated by TxA2 dependent podoplanin-CLEC2 signaling, leading to release of extracellular vesicles, thereby promoting CLEC5A and TLR2 mediated neutrophil activation, thromboinflammation, CVST, and thromboembolism in other vascular beds. Young age and female gender are associated with increased TxA2 generation and platelet activation respectively, and hence increased risk of thromboembolic complications following vaccination.
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Subject: APRIL 13. 2021 – J&J Statement – Out of an abundance of caution, the CDC and FDA have recommended a pause in the use of our vaccine. ->> Are there relations between these FINDINGS?
Johnson & Johnson Statement on COVID-19 Vaccine
NEW BRUNSWICK, N.J., April 13, 2021– The safety and well-being of the people who use our products is our number one priority. We are aware of an extremely rare disorder involving people with blood clots in combination with low platelets in a small number of individuals who have received our COVID-19 vaccine. The United States Centers for Disease Control (CDC) and Food and Drug Administration (FDA) are reviewing data involving six reported U.S. cases out of more than 6.8 million doses administered. Out of an abundance of caution, the CDC and FDA have recommended a pause in the use of our vaccine.
In addition, we have been reviewing these cases with European health authorities. We have made the decision to proactively delay the rollout of our vaccine in Europe.
We have been working closely with medical experts and health authorities, and we strongly support the open communication of this information to healthcare professionals and the public.
The CDC and FDA have made information available about proper recognition and management due to the unique treatment required with this type of blood clot. The health authorities advise that people who have received our COVID-19 vaccine and develop severe headache, abdominal pain, leg pain, or shortness of breath within three weeks after vaccination should contact their health care provider.
For more information on the Janssen COVID-19 vaccine, click here.
Please All send me your Expert Opinion on the relations between these FINDINGS?
Linking Thrombotic Thrombocytopenia to ChAdOx1 nCov-19 Vaccination, AstraZeneca | Leaders in Pharmaceutical Business Intelligence (LPBI) Group
Linking Thrombotic Thrombocytopenia to ChAdOx1 nCov-19 Vaccination, AstraZeneca
Reporter: Aviva Lev-Ari, PhD, RN
UPDATED on 4/13/2021
“Right now, these adverse events appear to be extremely rare,” Anne Schuchat, MD, principal deputy director of the CDC, and Peter Marks, MD, PhD, director of the FDA’s Center for Biologics Evaluation and Research, said in a joint statement from the two agencies. “COVID-19 vaccine safety is a top priority for the federal government, and we take all reports of health problems following COVID-19 vaccination very seriously.”
STATEMENT BY J&J
Johnson & Johnson Statement on COVID-19 Vaccine
NEW BRUNSWICK, N.J., April 13, 2021– The safety and well-being of the people who use our products is our number one priority. We are aware of an extremely rare disorder involving people with blood clots in combination with low platelets in a small number of individuals who have received our COVID-19 vaccine. The United States Centers for Disease Control (CDC) and Food and Drug Administration (FDA) are reviewing data involving six reported U.S. cases out of more than 6.8 million doses administered. Out of an abundance of caution, the CDC and FDA have recommended a pause in the use of our vaccine.
In addition, we have been reviewing these cases with European health authorities. We have made the decision to proactively delay the rollout of our vaccine in Europe.
We have been working closely with medical experts and health authorities, and we strongly support the open communication of this information to healthcare professionals and the public.
The CDC and FDA have made information available about proper recognition and management due to the unique treatment required with this type of blood clot. The health authorities advise that people who have received our COVID-19 vaccine and develop severe headache, abdominal pain, leg pain, or shortness of breath within three weeks after vaccination should contact their health care provider.
For more information on the Janssen COVID-19 vaccine, click here.
Thrombotic Thrombocytopenia after ChAdOx1 nCov-19 Vaccination, AstraZeneca
Several cases of unusual thrombotic events and thrombocytopenia have developed after vaccination with the recombinant adenoviral vector encoding the spike protein antigen of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (ChAdOx1 nCov-19, AstraZeneca).
This study found that vaccination with ChAdOx1 nCov-19 can result in the rare development of immune thrombotic thrombocytopenia mediated by platelet-activating antibodies against PF4, which clinically mimics autoimmune heparin-induced thrombocytopenia (aHIT).
This study also found that the addition of immune globulin in doses that are readily achieved clinically was effective in inhibiting platelet activation by patients’ antibodies.
Clinician reluctance to start anticoagulation may be tempered by administering high-dose intravenous immune globulin to raise the platelet count, especially when a patient presents with severe thrombocytopenia and thrombosis, such as cerebral venous thrombosis.
Given the parallels with autoimmune heparininduced thrombocytopenia, anticoagulant options should include nonheparin anticoagulants used for the management of heparin-induced thrombocytopenia, unless a functional test has excluded heparin-dependent enhancement of platelet activation.
Finally, this paper suggest naming this novel entity vaccine-induced immune thrombotic thrombocytopenia (VITT) to avoid confusion with heparin-induced thrombocytopenia.
Subject: Fwd: Vaccination thrombotic events clinically mimics Heparin-induced thrombocytopenia | CD8+ Memory T Cell Responses against Viral Variants
Thrombotic Thrombocytopenia after ChAdOx1 nCov-19 Vaccination
This article was published on April 9, 2021, at NEJM.org. DOI: 10.1056/NEJMoa2104840
BACKGROUND Several cases of unusual thrombotic events and thrombocytopenia have developed after vaccination with the recombinant adenoviral vector encoding the spike protein antigen of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (ChAdOx1 nCov-19, AstraZeneca). More data were needed on the pathogenesis of this unusual clotting disorder. METHODS We assessed the clinical and laboratory features of 11 patients in Germany and Austria in whom thrombosis or thrombocytopenia had developed after vaccination with ChAdOx1 nCov-19. We used a standard enzyme-linked immunosorbent assay to detect platelet factor 4 (PF4)–heparin antibodies and a modified (PF4-enhanced) platelet-activation test to detect platelet-activating antibodies under various reaction conditions. Included in this testing were samples from patients who had blood samples referred for investigation of vaccine-associated thrombotic events, with 28 testing positive on a screening PF4–heparin immunoassay. RESULTS Of the 11 original patients, 9 were women, with a median age of 36 years (range, 22 to 49). Beginning 5 to 16 days after vaccination, the patients presented with one or more thrombotic events, with the exception of 1 patient, who presented with fatal intracranial hemorrhage. Of the patients with one or more thrombotic events, 9 had cerebral venous thrombosis, 3 had splanchnic-vein thrombosis, 3 had pulmonary embolism, and 4 had other thromboses; of these patients, 6 died. Five patients had disseminated intravascular coagulation. None of the patients had received heparin before symptom onset. All 28 patients who tested positive for antibodies against PF4–heparin tested positive on the platelet-activation assay in the presence of PF4 independent of heparin. Platelet activation was inhibited by high levels of heparin, Fc receptor–blocking monoclonal antibody, and immune globulin (10 mg per milliliter). Additional studies with PF4 or PF4–heparin affinity purified antibodies in 2 patients confirmed PF4-dependent platelet activation. CONCLUSIONS Vaccination with ChAdOx1 nCov-19 can result in the rare development of immune thrombotic thrombocytopenia mediated by platelet-activating antibodies against PF4, which clinically mimics autoimmune heparin-induced thrombocytopenia. (Funded by the German Research Foundation.)
SOURCE
Thrombotic Thrombocytopenia after ChAdOx1 nCov-19 Vaccination
Andreas Greinacher, M.D., Thomas Thiele, M.D., Theodore E. Warkentin, M.D., Karin Weisser, Ph.D., Paul A. Kyrle, M.D., and Sabine Eichinger, M.D.
Author Affiliations
From Institut für Immunologie und Transfusionsmedizin, Universitätsmedizin Greifswald, Greifswald (A.G., T.T.), and the Division of Safety of Medicinal Products and Medical Devices, Paul-Ehrlich-Institut (Federal Institute for Vaccines and Biomedicines), Langen (K.W.) — both in Germany; the Departments of Pathology and Molecular Medicine and of Medicine, McMaster University, Hamilton, ON, Canada (T.E.W.); and the Department of Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Vienna (P.A.K., S.E.).
Address reprint requests to Dr. Greinacher at Institut für Immunologie und Transfusionsmedizin, Abteilung Transfusionsmedizin, Sauerbruchstrasse, 17487 Greifswald, Germany.
In 13 Viewpoints in this issue,2–14 JAMA Network editors reflect on the clinical, public health, operational, and workforce issues related to COVID-19 in each of their specialties. Questions and concerns they identify in their clinical communities include the following:
Benefits and harms of treatments and identifying mortality risk markers beyond age and comorbidities
Cardiovascular consequences of COVID-19 infection, including risks to those with comorbid hypertension and risks for myocardial injury
Risk for direct central nervous system invasion and COVID-19 encephalitis and for long-term neuropsychiatric manifestations in a post–COVID-19 syndrome
Risks related to SARS-CoV-2 infection for patients with compromised immunity, such as those receiving treatment for cancer
Challenges unique to patients with acute kidney injury and chronic kidney disease
Risks of viral transmission from aerosol-generating procedures, including most minimally invasive surgeries, and the need for eye protection as well as personal protective equipment as part of universal precautions
The prevalence and pathophysiology of skin findings in patients with COVID-19, determining if they are primary or secondary cutaneous manifestations of infection, and how best to manage them
The prevalence and significance of eye findings in patients with COVID-19 and the risk of transmission and infection through ocular surfaces
The role of anticoagulation for managing the endotheliopathy and coagulopathy characteristic of the infection in some patients
Developmental effects on children of the loss of family routines, finances, older loved ones, school and education, and social-based activities and milestone events
Effects of the pandemic, mitigation efforts, and economic downturn on the mental health of patients and frontline clinicians
Seasonality of transmission as the pandemic enters its third season
How to implement reliable seroprevalence surveys to document progression of the pandemic and effects of public health measures
Effects of the pandemic on access to care and the rise of telehealth
Consequences of COVID-19 for clinical capabilities, such as workforce availability in several specialties, delays in performing procedures and operations, and implications for medical education and resident recruitment.
Additional important questions that require careful observation and research include
Randomized evaluations of treatment: what is effective and safe, and what timing of which drug will reduce morbidity and mortality? Will a combination of therapies be more effective than any single drug?
Randomized evaluations of preventive interventions, including convalescent plasma, monoclonal antibodies, and vaccines. Which are effective and safe enough to prevent COVID-19 at a population level?
How can COVID-19 vaccines and therapeutics be distributed and paid for in ways that are fair and equitable?
Is immunity complete or partial, permanent or temporary, what is its mechanism, and how best is it measured? Can the virus mutate around host defenses?
How important are preadolescent children to the spread of infection to older family members and adult communities, and what are the implications for parent, caregiver, and teacher personal risk and disease transmission?
Is SARS-CoV-2 like influenza (continually circulating without or with seasonality), measles (transmissible but containable beneath threshold limits), or smallpox and polio (eradicable, or nearly so)?
Has the pandemic fundamentally altered the way health care is financed and delivered? By shining a spotlight on health inequities, can the pandemic motivate changes in health care finance, organization, and delivery to reduce those inequities?
The initial reports on the epidemiology of coronavirus disease 2019 (COVID-19) emanating from Wuhan, China, offered an ominous forewarning of the risks of severe complications in elderly patients and those with underlying cardiovascular disease, including the development of acute respiratory distress syndrome, cardiogenic shock, thromboembolic events, and death. These observations have been confirmed subsequently in numerous reports from around the globe, including studies from Europe and the US. The mechanisms responsible for this vulnerability have not been fully elucidated, but there are several possibilities. Some of these adverse consequences could reflect the basic fragility of older individuals with chronic conditions subjected to the stress of severe pneumonia similar to influenza infections. In addition, development of type 2 myocardial infarction related to increased myocardial oxygen demand in the setting of hypoxia may be a predominant concern, and among patients with chronic coronary artery disease, an episode of acute systemic inflammation might also contribute to plaque instability, thus precipitating acute coronary syndromes, as has also been reported during influenza outbreaks.
However, in the brief timeline of the current pandemic, numerous publications highlighting the constellation of observed cardiovascular consequences have emphasized certain distinctions that appear unique to COVID-19.1 Although the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) gains entry via the upper respiratory tract, its affinity and selective binding to the angiotensin-converting enzyme 2 (ACE2) receptor, which is abundant in the endothelium of arteries and veins as well as in the respiratory tract epithelium, create a scenario in which COVID-19 is as much a vascular infection as it is a respiratory infection with the potential for serious vascular-related complications. This may explain why hypertension is one of the cardiovascular conditions associated with adverse outcomes. In the early stages of the pandemic, the involvement of the ACE2 receptor as the target for viral entry into cells created concerns regarding the initiation or continuation of treatment with ACE inhibitors and angiotensin receptor antagonists in patients with hypertension, left ventricular dysfunction, or other cardiac conditions. Subsequently, many studies have shown that these drugs do not increase susceptibility to infection or increase disease severity in those who contract the disease,2 thus supporting recommendations from academic societies that these drugs should not be discontinued in patients who develop COVID-19 infections.
Thrombosis, arterial or venous, is a hallmark of severe COVID-19 infections, related both to vascular injury and the prothrombotic cytokines released during the intense systemic inflammatory and immune responses.3 This sets the stage for serious thrombotic complications including acute coronary syndromes, ischemic strokes, pulmonary embolism, and ischemic damage to multiple other organ systems. Such events can complicate the course of any patient with COVID-19 but would be particularly devasting to individuals with preexisting cardiovascular disease.
Another unique aspect of COVID-19 infections that is not encountered by patients with influenza is myocardial injury, manifested by elevated levels of circulating troponin, creatinine kinase-MB, and myoglobin. Hospitalized patients with severe COVID-19 infections and consequent evidence of myocardial injury have a high risk of in-hospital mortality.4 Troponin elevations are most concerning, and when accompanied by elevations of brain natriuretic peptide, the risk is further accentuated. Although myocardial injury could reflect a COVID-19–related acute coronary event, most patients with troponin elevations who undergo angiography do not have epicardial coronary artery obstruction. Rather, those with myocardial injury have a high incidence of acute respiratory distress syndrome, elevation of D-dimer levels, and markedly elevated inflammatory biomarkers such as C-reactive protein and procalcitonin, suggesting that the combination of hypoxia, microvascular thrombosis, and systemic inflammation contributes to myocardial injury. Myocarditis is a candidate explanation for myocardial injury but has been difficult to confirm consistently. However, features of myocarditis have been reported in case reports5 based on clinical presentation and results of noninvasive imaging, but thus far confirmation of myocarditis based on myocardial biopsy or autopsy examinations has been a rare finding.6 Instead, myocardial tissue samples more typically show vascular or perivascular inflammation (endothelialitis) without leukocytic infiltration or myocyte damage.
There remain important unknowns regarding the intermediate and long-term sequelae of COVID-19 infection among hospital survivors. In an autopsy series of patients who died from confirmed COVID-19 without clinical or histological evidence of fulminant myocarditis,7 viral RNA was identified in myocardial tissue in 24 of 39 cases, with viral load of more than 1000 copies/μg of RNA in 16 cases. A cytokine response panel demonstrated upregulation of 6 proinflammatory genes (tumor necrosis factor, interferon γ, CCL4, and interleukin 6, 8, and 18) in the 16 myocardial samples with the high viral RNA levels.
Whether a subclinical viral load and associated cytokine response such as this in survivors of COVID-19 could translate into subsequent myocardial dysfunction and clinical heart failure require further investigation. However, the results of a recent biomarker and cardiac magnetic resonance (CMR) imaging study provide evidence to support this concern.6 Among 100 patients who were studied by CMR after recovery from confirmed COVID-19 infection, of whom 67 did not require hospitalization during the acute phase, left ventricular volume was greater and ejection fraction was lower than that of a control group. Furthermore, 78 patients had abnormal myocardial tissue characterization by CMR, with elevated T1 and T2 signals and myocardial hyperenhancement consistent with myocardial edema and inflammation, and 71 patients had elevated levels of high-sensitivity troponin T. Three patients with the most severe CMR abnormalities underwent myocardial biopsy, with evidence of active lymphocytic infiltration.6 It is noteworthy that all 100 patients in this series had negative COVID-19 test results at the time of CMR study (median, 71 days; interquartile range [IQR], 64-92 days after acute infection). The results of these relatively small series should be interpreted cautiously until confirmed by larger series with longer follow-up and with confirmed clinical outcomes. But the findings do underscore the uncertainty regarding the long-term cardiovascular consequences of COVID-19 in patients who have ostensibly recovered. Of note, a randomized clinical trial of anticoagulation to reduce the risk of thrombotic complications in the posthospital phase of COVID-19 infection is under development through the National Institutes of Health’s set of ACTIV (Accelerating COVID-19 Therapeutic Interventions and Vaccines) initiatives.
In addition, the indirect effects of COVID-19 have become a major concern. Multiple observations during the COVID-19 pandemic confirm a sudden and inexplicable decline in rates of hospital admissions for ST–segment elevation myocardial infarction and other acute coronary syndromes beginning in March and April 2020. This has been a universal experience, with similar findings reported from multiple countries around the world in single-center observations, multicenter registries, and national databases. A concerning increase in out-of-hospital cardiac arrests has also been reported.8 These data suggest that COVID-19 has influenced health care–seeking behavior resulting in fewer presentations of acute coronary syndromes in emergency departments and more out-of-hospital events. Failure to seek appropriate emergency cardiac care could contribute to the observations of increased number of deaths and cardiac arrests, more than the anticipated average during this period8,9 with worse outcomes among those who ultimately do seek care.10 Recent data suggest that admission rates for myocardial infarction may be returning to baseline,10 but outcomes will improve only if patients seek care promptly and hospital systems are not overwhelmed by COVID-19 surges.
Given the ongoing activity of COVID-19, very clear messaging to the public and patients should include the following: heed the warning signs of heart attack, act promptly to initiate emergency medical services, and seek immediate care in hospitals, which have taken every step needed to be safe places. And especially, the messaging should continuously underscore the most important considerations that have been extant since this crisis began—wear a mask and practice physical distancing. In the meantime, the generation of rigorous evidence to inform best practices for diagnosis and management of COVID-19–related cardiovascular disease is a global imperative.
Corresponding Author: Robert O. Bonow, MD, MS, Division of Cardiology, Northwestern University Feinberg School of Medicine, 676 N St Clair St, Ste 600, Chicago, IL 60611 (r-bonow@northwestern.edu)
Bradykinin Hypothesis: Potential Explanation for COVID-19
Reporter: Aviva Lev-Ari, PhD, RN
UPDATED on 9/14/2020
First Randomized Trial Backs Safety of ACE and ARB Heart Drugs in COVID-19 Patients
BRACE CORONA trial presented in a Hot Line Session at ESC Congress 2020
September 8, 2020 – Heart patients hospitalized with COVID-19 (SARS-CoV-2) can safely continue taking angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs), according to the BRACE CORONA trial presented in a Hot Line session at the virtual European Society of Cardiology (ESC) Congress 2020.[1]
ACE inhibitors and ARBs are commonly taken by heart patients to reduce blood pressure and to treat heart failure. There is conflicting observational evidence about the potential clinical impact of ACE inhibitors and ARBs on patients with COVID-19.[2] Select preclinical investigations have raised concerns about their safety in patients with COVID-19. Preliminary data hypothesize that renin-angiotensin-aldosterone system (RAAS) inhibitors could benefit patients with COVID-19 by decreasing acute lung damage and preventing angiotensin-II-mediated pulmonary inflammation.
Given the frequent use of these agents worldwide, randomized clinical trial evidence is urgently needed to guide the management of patients with COVID-19.
The BRACE CORONA TRIAL compared outcomes for COVID19 patients previously on ACE inhibitor or ARB of holding the medication for a month, or not, and saw no significant benefit from withholding either class of medication. The basis for specific concern is the fact that the COVID19 virus utilizes ACE2 receptors for its invasion, and that disturbances in the renin-angiotensin and bradykinin levels and capillary leak have been observed with COVID19 infections. ACEI and ARB medications both modulate the renin angiotensin system, but with different impact on bradykinin levels. Changes in bradykinin levels cause for dry cough seen with ACE inhibitors like lisinopril that are not seen with angiotensin receptor blockers (ARB) such as Losartan. The absence of significant differences in outcome measures by holding either drug weakens the Jacobson’s bradykinin hypothesis based on a cascade of observations related to the ACE2 receptor and downstream effects. The new observations on safety of both ACEI and ARB weaken Jacobson’s hypothesis of a primary importance of renin angiotensin and bradykinin changes in the course and complications of COVID19 infection.
The ACE gene product degrades bradykinin. Jacobson’s bradykinin hypothesis suggested that the observations of capillary leak and disturbances in the renal angiotensin system may be prime factors rather than bystanders. Jacobson made strong statements from associations, but the lack of impact of stoppage of either ACE inhibitors or Angiotensin Receptor Blockers (ARB) argues that his observations are not major in determination of outcomes.
Bradykinin Hypothesis: Potential Explanation for COVID-19
The entry point for the virus is ACE2, which is a component of the counteracting hypotensive axis of RAS. Bradykinin is a potent part of the vasopressor system that induces hypotension and vasodilation and is degraded by ACE and enhanced by the angiotensin1-9 produced by ACE2.
critical imbalance in RAS represented by decreased expression of ACE in combination with increases in ACE2, renin, angiotensin, key RAS receptors, kinogen and many kallikrein enzymes that activate it, and both bradykinin receptors. This very atypical pattern of the RAS is predicted to elevate bradykinin levels in multiple tissues and systems that will likely cause increases in vascular dilation, vascular permeability and hypotension. These bradykinin-driven outcomesexplain many of the symptoms being observed in COVID-19.
Jacobson says, “What we’ve found is that the imbalance in the renin-angiotensin system (RAS) pathway that appeared to be present in Covid-19 patients could be responsible for constantly resensitizing bradykinin receptors. So, this imbalance in the RAS pathways will take the brakes off the bottom of the bradykinin pathway at the receptor level. In addition, the downregulation of the ACE gene in Covid-19 patients, which usually degrades bradykinin, is another key imbalance in the regulation of bradykinin levels. We have also observed that the key negative regulator at the top of the bradykinin pathway is dramatically down-regulated. Thus, you likely have an increase in bradykin production as well, stopping many of the braking mechanisms usually in place, so the bradykinin signal spirals out of control.”
The bradykinin hypothesis also extends to many of Covid-19’s effects on the heart. About one in five hospitalized Covid-19 patients have damage to their hearts, even if they never had cardiac issues before. Some of this is likely due to the virus infecting the heart directly through its ACE2 receptors. But the RAS also controls aspects of cardiac contractions and blood pressure. According to the researchers, bradykinin storms could create arrhythmias and low blood pressure, which are often seen in Covid-19 patients.
“the pathology of Covid-19 is likely the result of Bradykinin Storms rather than cytokine storms,” which had been previously identified in Covid-19 patients, but that “the two may be intricately linked.”
According to Jacobson and his team, MRI studies in France revealed that many Covid-19 patients have evidence of leaky blood vessels in their brains.
bradykinin would indeed be likely to increase the permeability of the blood-brain barrier. In addition, similar neurological symptoms have been observed in other diseases that result from an excess of bradykinin.”
Increased bradykinin levels could also account for other common Covid-19 symptoms. ACE inhibitors — a class of drugs used to treat high blood pressure — have a similar effect on the RAS system as Covid-19, increasing bradykinin levels. In fact, Jacobson and his team note in their paper that “the virus… acts pharmacologically as an ACE inhibitor” — almost directly mirroring the actions of these drugs.
repurpose existing FDA approved drugs such as Danazol, Stanasolol, Icatibant, Ecallantide, Berinert, Cynryze, Haegarda, etc.. to reduce the amount of bradykinin signaling to prevent the escalation of the bradykinin storm.
Partnerships with pharmaceutical companies and clinical research are needed to design and implement the right clinical trials to see how these types of treatments can be applied.
Systems biology perspective and think that attempts to inhibit the virus itself will also probably require a combinatorial strategy it’s possible that we will need a combinatorial approach to therapies both on the human side and on the viral side
Other compounds could treat symptoms associated with bradykinin storms. Hymecromone, for example, could reduce hyaluronic acid levels, potentially stopping deadly hydrogels from forming in the lungs. And timbetasin could mimic the mechanism that the researchers believe protects women from more severe Covid-19 infections
A Supercomputer Analyzed Covid-19 — and an Interesting New Theory Has Emerged
A closer look at the Bradykinin hypothesis
Thomas Smith Sep 1, 2020
Earlier this summer, the Summit supercomputer at Oak Ridge National Lab in Tennessee set about crunching data on more than 40,000 genes from 17,000 genetic samples in an effort to better understand Covid-19. Summit is the second-fastest computer in the world, but the process — which involved analyzing 2.5 billion genetic combinations — still took more than a week.
When Summit was done, researchers analyzed the results. It was, in the words of Dr. Daniel Jacobson, lead researcher and chief scientist for computational systems biology at Oak Ridge, a “eureka moment.” The computer had revealed a new theory about how Covid-19 impacts the body: the bradykinin hypothesis. The hypothesis provides a model that explains many aspects of Covid-19, including some of its most bizarre symptoms. It also suggests 10-plus potential treatments, many of which are already FDA approved. Jacobson’s group published their results in a paper in the journal eLife in early July.
According to the team’s findings, a Covid-19 infection generally begins when the virus enters the body through ACE2 receptors in the nose, (The receptors, which the virus is known to target, are abundant there.) The virus then proceeds through the body, entering cells in other places where ACE2 is also present: the intestines, kidneys, and heart. This likely accounts for at least some of the disease’s cardiac and GI symptoms.
Oak Ridge National Laboratory, Biosciences Division, United States;
University of Tennessee Knoxville, The Bredesen Center for Interdisciplinary Research and Graduate Education, United States;
University of Kentucky, Department of Horticulture, United States;
Versiti Blood Research Institute, Medical College of Wisconsin, United States;
VA Connecticut Healthcare/General Internal Medicine, Yale University School of Medicine, United States;
University of Cincinnati, United States;
Biomedical Informatics, Cincinnati Children’s Hospital Research Foundation, United States;
University of Tennessee Knoxville, Department of Psychology, Austin Peay Building, United States
Abstract
Neither the disease mechanism nor treatments for COVID-19 are currently known. Here, we present a novel molecular mechanism for COVID-19 that provides therapeutic intervention points that can be addressed with existing FDA-approved pharmaceuticals. The entry point for the virus is ACE2, which is a component of the counteracting hypotensive axis of RAS. Bradykinin is a potent part of the vasopressor system that induces hypotension and vasodilation and is degraded by ACE and enhanced by the angiotensin1-9 produced by ACE2.Here, we perform a new analysis on gene expression data from cells in bronchoalveolar lavage fluid (BALF) from COVID-19 patients that were used to sequence the virus. Comparison with BALF from controls identifies a critical imbalance in RAS represented by decreased expression of ACE in combination with increases in ACE2, renin, angiotensin, key RAS receptors, kinogen and many kallikrein enzymes that activate it, and both bradykinin receptors. This very atypical pattern of the RAS is predicted to elevate bradykinin levels in multiple tissues and systems that will likely cause increases in vascular dilation, vascular permeability and hypotension. These bradykinin-driven outcomes explain many of the symptoms being observed in COVID-19.
*Correspondence
Joseph A. Roche, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, 259 Mack Ave., Detroit, MI 48201, USA.
Email: ude.enyaw@ehcor.hpesoj,
Abstract
As of April 20, 2020, over time, the COVID‐19 pandemic has resulted in 157 970 deaths out of 2 319 066 confirmed cases, at a Case Fatality Rate of ~6.8%. With the pandemic rapidly spreading, and health delivery systems being overwhelmed, it is imperative that safe and effective pharmacotherapeutic strategies are rapidly explored to improve survival. In this paper, we use established and emerging evidence to propose a testable hypothesis that, a vicious positive feedback loop of des‐Arg(9)‐bradykinin‐ and bradykinin‐mediated inflammation → injury → inflammation, likely precipitates life threatening respiratory complications in COVID‐19. Through our hypothesis, we make the prediction that the FDA‐approved molecule, icatibant, might be able to interrupt this feedback loop and, thereby, improve the clinical outcomes. This hypothesis could lead to basic, translational, and clinical studies aimed at reducing COVID‐19 morbidity and mortality.
COVID-19 patients can present with pulmonary edema early in disease. We propose that this is due to a local vascular problem because of activation of bradykinin 1 receptor (B1R) and B2R on endothelial cells in the lungs. SARS-CoV-2 enters the cell via ACE2 that next to its role in RAAS is needed to inactivate des-Arg9 bradykinin, the potent ligand of the B1R. Without ACE2 acting as a guardian to inactivate the ligands of B1R, the lung environment is prone for local vascular leakage leading to angioedema. Here, we hypothesize that a kinin-dependent local lung angioedema via B1R and eventually B2R is an important feature of COVID-19. We propose that blocking the B2R and inhibiting plasma kallikrein activity might have an ameliorating effect on early disease caused by COVID-19 and might prevent acute respiratory distress syndrome (ARDS). In addition, this pathway might indirectly be responsive to anti-inflammatory agents.
Kinins and cytokines in COVID-19: a comprehensive pathophysiological approach
Frank L. van de Veerdonk1*, Mihai G. Netea1,2, Marcel van Deuren1, Jos W.M. van der Meer1, Quirijn de Mast1, Roger J. Brüggemann3, Hans van der Hoeven4
doi:10.20944/preprints202004.0023.v1
Abstract
Most striking observations in COVID-19 patients are the hints on pulmonary edema (also seen on CT scans as ground glass opacities), dry cough, fluid restrictions to prevent more severe hypoxia, the huge PEEP that is needed while lungs are compliant, and the fact that antiinflammatory therapies are not powerful enough to counter the severity of the disease. We propose that the severity of the disease and many deaths are due to a local vascular problem due to activation of B1 receptors on endothelial cells in the lungs. SARS-CoV-2 enters the cell via ACE2, a cell membrane bound molecule with enzymatic activity that next to its role in RAS is needed to inactivate des-Arg9 bradykinin, the potent ligand of the bradykinin receptor type 1 (B1). In contrast to bradykinin receptor 2 (B2), the B1 receptor on endothelial cells is upregulated by proinflammatory cytokines. Without ACE2 acting as a guardian to inactivate the ligands of B1, the lung environment is prone for local vascular leakage leading to angioedema. Angioedema is likely a feature already early in disease, and might explain the typical CT scans and the feeling of people that they drown. In some patients, this is followed by a clinical worsening of disease around day 9 due to the formation antibodies directed against the spike (S)-antigen of the corona-virus that binds to ACE2 that could contribute to disease by enhancement of local immune cell influx and proinflammatory cytokines leading to damage. In parallel, inflammation induces more B1 expression, and possibly via antibody-dependent enhancement of viral infection leading to continued ACE2 dysfunction in the lung because of persistence of the virus. In this viewpoint we propose that a bradykinin-dependent local lung angioedema via B1 and B2 receptors is an important feature of COVID-19, resulting in a very high number of ICU admissions. We propose that blocking the B1 and B2 receptors might have an ameliorating effect on disease caused by COVID-19. This kinin-dependent pulmonary edema is resistant to corticosteroids or adrenaline and should be targeted as long as the virus is present. In addition, this pathway might indirectly be responsive to anti-inflammatory agents or neutralizing strategies for the anti-S-antibody induced effects, but by itself is likely to be insufficient to reverse all the pulmonary edema. Moreover, we provide a suggestion of how to ventilate in the ICU in the context of this hypothesis.
Emerging Pandemic Diseases: How We Got to COVID-19
David M. Morens1,* and Anthony S. Fauci1
1Office of the Director, National Institute of Allergy & Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
Infectious diseases prevalent in humans and animals are caused by pathogens that once emerged from other animal hosts. In addition to these established infections, new infectious diseases periodically emerge. In extreme cases they may cause pandemics such as COVID-19; in other cases, dead-end infections or smaller epidemics result. Established diseases may also re-emerge, for example by extending geographically or by becoming more transmissible or more pathogenic. Disease emergence reflects dynamic balances and imbalances, within complex globally distributed ecosystems comprising humans, animals, pathogens, and the environment. Understanding these variables is a necessary step in controlling future devastating disease emergences.
SARS-CoV-2 infects and damages the cells lining blood vessels, it could expose the tissue underneath
clotting results from inflammation. And here, many experts are eyeing a set of proteins called the complement system
These proteins, known collectively as complement, attack invaders and call in other parts of the immune system to assist. They also can activate platelets and promote clotting.
Claudia Kemper1,2,3 said “complementologists think that this is a massive part of the disease” signs of complement activity in the lungs and livers of people who died from Covid-19
Laurence found several active complement proteins in the skin and blood vessels of his early Covid-19 clotting cases
Genes involved in complement and clotting responses were more active when the virus was present in patients’ nasal swabs.
immune element may promote clotting in severe Covid-19 cases: an overreaction called a cytokine storm, in which the body releases an excess of inflammation-promoting cytokine molecules.
Body’s response in need of control: (1) control the clotting, (2) control the inflammation, (2) control the complement pathway in tandem with antiviral Remdesivir that controls the viral replication thus the viral load.
Balance the risk of clotting with the danger of bleeding (bleeds into the digestive system for these patients, but they may also hemorrhage in the lungs, brain or spots where medical devices pierce the skin)
Dosage of blood thinners is debated – 40 Studies found for: anticoagulation | Covid19
there is no evidence that people with less severe Covid-19, who do not require hospitalization, should take blood thinners or aspirin to ward off clots.
Management of Clotting: Argatroban, for example, is a Food and Drug Administration-approved anticoagulant that interferes with thrombin, an element of the clotting cascade. Eculizumab, which blocks one of the complement proteins, is approved for certain inflammatory conditions.
Clinical judgement is used in light of lack of evidence
SOURCES
Why Blood Clots Are a Major Problem in Severe Covid-19
Erin E. West,1 Martin Kolev,2 and Claudia Kemper1,2,3
1Laboratory of Molecular Immunology and Immunology Center, National Heart, Lung and Blood Institute, Bethesda, Maryland 20892, United States; email: erin.west@nih.gov, claudia.kemper@nih.gov
2Division of Transplant Immunology and Mucosal Biology, King’s College London, London SE1 9RT, United Kingdom; email: martin.kolev@kcl.ac.uk
3Institute for Systemic Inflammation Research, University of Lübeck, 23562 Lübeck, Germany
The complement system is an evolutionarily ancient key component of innate immunity required for the detection and removal of invading pathogens. It was discovered more than 100 years ago and was originally defined as a liver-derived, blood-circulating sentinel system that classically mediates the opsonization and lytic killing of dangerous microbes and the initiation of the general inflammatory reaction. More recently, complement has also emerged as a critical player in adaptive immunity via its ability to instruct both B and T cell responses. In particular, work on the impact of complement on T cell responses led to the surprising discoveries that the complement system also functions within cells and is involved in regulating basic cellular processes, predominantly those of metabolic nature. Here, we review current knowledge about complement’s role in T cell biology, with a focus on the novel intracellular and noncanonical activities of this ancient system.
Complement Dysregulation and Disease: Insights from Contemporary Genetics
M. Kathryn Liszewski,1 Anuja Java,2
Elizabeth C. Schramm,3 and John P. Atkinson1
1Division of Rheumatology, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110; email: j.p.atkinson@wustl.edu
2Division of Nephrology, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
alternative complement pathway, C3 glomerulopathies, factor H, CD46,
factor I, C3, factor B
Abstract
The vertebrate complement system consists of sequentially interacting proteins that provide for a rapid and powerful host defense. Nearly 60 proteins comprise three activation pathways (classical, alternative, and lectin) and a terminal cytolytic pathway common to all. Attesting to its potency, nearly half of the system’s components are engaged in its regulation. An emerging theme over the past decade is that variations in these inhibitors predispose to two scourges of modern humans. One, occurring most often in childhood, is a rare but deadly thrombomicroangiopathy called atypical hemolytic uremic syndrome. The other, age-related macular degeneration, is the most common form of blindness in the elderly. Their seemingly unrelated clinical presentations and pathologies share the common theme of overactivity of the complement system’s alternative pathway. This review summarizes insights gained from contemporary genetics for understanding how dysregulation of this powerful innate immune system leads to these human diseases.
CONCLUSIONS AND PERSPECTIVES
Over the last decade, a remarkable advance has been the elucidation of the role of mutations in complement regulators and components in aHUS, AMD, and C3G. Next-generation sequencing has led theway to these discoveries, but functional assessments are the critical factors in definitively associating pathogenesis with genetic variants.
Most exciting has been the development and approval by the FDA of the monoclonal antibody, eculizumab, as the new standard of care for treatment of aHUS. Challenges remain, however because eculizumab is costly and the duration of treatment remains uncertain and warrants further prospective studies. The use of eculizumab in C3G should also be prospectively addressed.
Furthermore, given the increasing number of mutations in the complement regulatory proteins identified in aHUS and C3G and the heterogeneity in the mechanisms leading to dysregulation of the AP, there is a need for further assessment of the genetic variants of unknown significance. As yet, no complement inhibitor has been approved to treat AMD.
These analyses coupled with the anticipated new developments of complement therapeutics will help establish patient-tailored therapies based on each patient’s specific alteration. The future holds much promise for the further delineation of complement-disease associations and for novel complement-targeted therapeutic agents.
Patients with coronavirus disease 2019 (COVID-19) present with a range of devastating acute clinical manifestations affecting the lungs, liver, kidneys and gut. The best-characterized entry receptor for the disease-causing virus SARS-CoV2, angiotensin converting enzyme (ACE) 2, is highly expressed in these tissues. However, the pathways that underlie the disease are still poorly understood. Here we show that the complement system is unexpectedly one of the intracellular pathways most highly induced by SARS-CoV2 infection in lung epithelial and liver cells. Within cells of the bronchoalveolar lavage of patients, distinct signatures of complement activation in myeloid, lymphoid and epithelial cells tracked with disease severity. Modelling the regulome of host genes induced by COVID-19 and the drugs that could normalize these genes both implicated the JAK1/2-STAT1 signaling system downstream of type I interferon receptors, and NF-kB.
Ruxolitinib, a JAK1/2 inhibitor and the top predicted pharmaceutical candidate, normalized interferon signature genes, IL-6 (the best characterized severity marker in COVID-19) and all complement genes induced by SARS-CoV2, but did not affect NF-kB-regulated genes. We predict that combination therapy with JAK inhibitors and other agents with the potential to normalize NFkB-signaling, such as anti-viral agents, may serve as an effective clinical strategy.
New Etiology for COVID-19: Death results from Immune-Mediation (virus-independent immunopathology: lung and reticuloendothelial system) vs Pathogen-Mediation causing Organ Dysfunction & Hyper-Inflammation – Immunomodulatory Therapeutic Approaches (dexamethasone)
Curators: Stephen J. Williams and Aviva Lev-Ari, PhD, RN
Corticosteroid, Dexamethasone Improves Survival in COVID-19: Deaths reduction by 1/3 in ventilated patients and by 1/5 in other patients receiving oxygen only
Reporter: Aviva Lev-Ari, PhD, RN – bold face and color fonts added
As part of the all-of-America approach to fighting the COVID-19 pandemic, the U.S. Food and Drug Administration has been working with partners across the U.S. government, academia and industry to expedite the development and availability of critical medical products to treat this novel virus. Today, we are providing an update on one potential treatment called convalescent plasma and encouraging those who have recovered from COVID-19 to donate plasma to help others fight this disease.
Convalescent plasma is an antibody-rich product made from blood donated by people who have recovered from the disease caused by the virus. Prior experience with respiratory viruses and limited data that have emerged from China suggest that convalescent plasma has the potential to lessen the severity or shorten the length of illness caused by COVID-19. It is important that we evaluate this potential therapy in the context of clinical trials, through expanded access, as well as facilitate emergency access for individual patients, as appropriate.
The response to the agency’s recently announced national efforts to facilitate the development of and access to convalescent plasma has been tremendous. More than 1,040 sites and 950 physician investigators nationwide have signed on to participate in the Mayo Clinic-ledExternal Link Disclaimer expanded access protocol. A number of clinical trials are also taking place to evaluate the safety and efficacy of convalescent plasma and the FDA has granted numerous single patient emergency investigational new drug (eIND) applications as well.
FDA issues guidelines on clinical trials and obtaining emergency enrollment concerning convalescent plasma
FDA has issued guidance to provide recommendations to health care providers and investigators on the administration and study of investigational convalescent plasma collected from individuals who have recovered from COVID-19 (COVID-19 convalescent plasma) during the public health emergency.
The guidance provides recommendations on the following:
Because COVID-19 convalescent plasma has not yet been approved for use by FDA, it is regulated as an investigational product. A health care provider must participate in one of the pathways described below. FDA does not collect COVID-19 convalescent plasma or provide COVID-19 convalescent plasma. Health care providers or acute care facilities should instead obtain COVID-19 convalescent plasma from an FDA-registered blood establishment.
Excerpts from the guidance document are provided below.
Background
The Food and Drug Administration (FDA or Agency) plays a critical role in protecting the United States (U.S.) from threats including emerging infectious diseases, such as the Coronavirus Disease 2019 (COVID-19) pandemic. FDA is committed to providing timely guidance to support response efforts to this pandemic.
One investigational treatment being explored for COVID-19 is the use of convalescent plasma collected from individuals who have recovered from COVID-19. Convalescent plasma that contains antibodies to severe acute respiratory syndrome coronavirus 2 or SARS-CoV-2 (the virus that causes COVID-19) is being studied for administration to patients with COVID-19. Use of convalescent plasma has been studied in outbreaks of other respiratory infections, including the 2003 SARS-CoV-1 epidemic, the 2009-2010 H1N1 influenza virus pandemic, and the 2012 MERS-CoV epidemic.
Although promising, convalescent plasma has not yet been shown to be safe and effective as a treatment for COVID-19. Therefore, it is important to study the safety and efficacy of COVID-19 convalescent plasma in clinical trials.
Pathways for Use of Investigational COVID-19 Convalescent Plasma
The following pathways are available for administering or studying the use of COVID-19 convalescent plasma:
Clinical Trials
Investigators wishing to study the use of convalescent plasma in a clinical trial should submit requests to FDA for investigational use under the traditional IND regulatory pathway (21 CFR Part 312). CBER’s Office of Blood Research and Review is committed to engaging with sponsors and reviewing such requests expeditiously. During the COVID-19 pandemic, INDs may be submitted via email to CBERDCC_eMailSub@fda.hhs.gov.
Expanded Access
An IND application for expanded access is an alternative for use of COVID-19 convalescent plasma for patients with serious or immediately life-threatening COVID-19 disease who are not eligible or who are unable to participate in randomized clinical trials (21 CFR 312.305). FDA has worked with multiple federal partners and academia to open an expanded access protocol to facilitate access to COVID-19 convalescent plasma across the nation. Access to this investigational product may be available through participation of acute care facilities in an investigational expanded access protocol under an IND that is already in place.
Although participation in clinical trials or an expanded access program are ways for patients to obtain access to convalescent plasma, for various reasons these may not be readily available to all patients in potential need. Therefore, given the public health emergency that the COVID-19 pandemic presents, and while clinical trials are being conducted and a national expanded access protocol is available, FDA also is facilitating access to COVID-19 convalescent plasma for use in patients with serious or immediately life-threatening COVID-19 infections through the process of the patient’s physician requesting a single patient emergency IND (eIND) for the individual patient under 21 CFR 312.310. This process allows the use of an investigational drug for the treatment of an individual patient by a licensed physician upon FDA authorization, if the applicable regulatory criteria are met. Note, in such case, a licensed physician seeking to administer COVID-19 convalescent plasma to an individual patient must request the eIND (see 21 CFR 312.310(b)).
Today, the U.S. Food and Drug Administration issued an emergency use authorization (EUA) for investigational convalescent plasma for the treatment of COVID-19 in hospitalized patients as part of the agency’s ongoing efforts to fight COVID-19. Based on scientific evidence available, the FDA concluded, as outlined in its decision memorandum, this product may be effective in treating COVID-19 and that the known and potential benefits of the product outweigh the known and potential risks of the product.
Today’s action follows the FDA’s extensive review of the science and data generated over the past several months stemming from efforts to facilitate emergency access to convalescent plasma for patients as clinical trials to definitively demonstrate safety and efficacy remain ongoing.
The EUA authorizes the distribution of COVID-19 convalescent plasma in the U.S. and its administration by health care providers, as appropriate, to treat suspected or laboratory-confirmed COVID-19 in hospitalized patients with COVID-19.
Alex Azar, Health and Human Services Secretary:
“The FDA’s emergency authorization for convalescent plasma is a milestone achievement in President Trump’s efforts to save lives from COVID-19,” said Secretary Azar. “The Trump Administration recognized the potential of convalescent plasma early on. Months ago, the FDA, BARDA, and private partners began work on making this product available across the country while continuing to evaluate data through clinical trials. Our work on convalescent plasma has delivered broader access to the product than is available in any other country and reached more than 70,000 American patients so far. We are deeply grateful to Americans who have already donated and encourage individuals who have recovered from COVID-19 to consider donating convalescent plasma.”
Stephen M. Hahn, M.D., FDA Commissioner:
“I am committed to releasing safe and potentially helpful treatments for COVID-19 as quickly as possible in order to save lives. We’re encouraged by the early promising data that we’ve seen about convalescent plasma. The data from studies conducted this year shows that plasma from patients who’ve recovered from COVID-19 has the potential to help treat those who are suffering from the effects of getting this terrible virus,” said Dr. Hahn. “At the same time, we will continue to work with researchers to continue randomized clinical trials to study the safety and effectiveness of convalescent plasma in treating patients infected with the novel coronavirus.”
Scientific Evidence on Convalescent Plasma
Based on an evaluation of the EUA criteria and the totality of the available scientific evidence, the FDA’s Center for Biologics Evaluation and Research determined that the statutory criteria for issuing an EUA criteria were met.
The FDA determined that it is reasonable to believe that COVID-19 convalescent plasma may be effective in lessening the severity or shortening the length of COVID-19 illness in some hospitalized patients. The agency also determined that the known and potential benefits of the product, when used to treat COVID-19, outweigh the known and potential risks of the product and that that there are no adequate, approved, and available alternative treatments.
CLINICAL MEMORANDUM From: , OBRR/DBCD/CRS To: , OBRR Through: , OBRR/DBCD , OBRR/DBCD , OBRR/DBCD/CRS Re: EUA 26382: Emergency Use Authorization (EUA) Request (original request 8/12/20; amended request 8/23/20) Product: COVID-19 Convalescent Plasma Items reviewed: EUA request Fact Sheet for Health Care Providers Fact Sheet for Recipients Sponsor: Robert Kadlec, M.D. Assistant Secretary for Preparedness and Response (ASPR) Office of Assistant Secretary for Preparedness and Response (ASPR) U.S. Department of Health and Human Services (HHS) EXECUTIVE SUMMARY COVID-19 Convalescent Plasma (CCP), an unapproved biological product, is proposed for use under an Emergency Use Authorization (EUA) under section 564 of the Federal Food, Drug, and Cosmetic Act (the Act),(21 USC 360bbb-3) as a passive immune therapy for the treatment of hospitalized patients with COVID-19, a serious or life-threatening disease. There currently is no adequate, approved, and available alternative to CCP for treating COVID-19. The sponsor has pointed to four lines of evidence to support that CCP may be effective in the treatment of hospitalized patients with COVID-19: 1) History of convalescent plasma for respiratory coronaviruses; 2) Evidence of preclinical safety and efficacy in animal models; 3) Published studies of the safety and efficacy of CCP; and 4) Data on safety and efficacy from the National Expanded Access Treatment Protocol (EAP) sponsored by the Mayo Clinic. Considering the totality of the scientific evidence presented in the EUA, I conclude that current data for the use of CCP in adult hospitalized patients with COVID-19 supports the conclusion that CCP meets the “may be effective” criterion for issuance of an EUA from section 564(c)(2)(A) of the Act. It is reasonable to conclude that the known and potential benefits of CCP outweigh the known and potential risks of CCP for the proposed EUA. Current data suggest the largest clinical benefit is associated with high-titer units of CCP administered early course of the disease.
A letter, from Senator Warren, to Commissioner Hahn from Senate Committee asking for documentation for any communication between FDA and White House
August 25, 2020 Dr. Stephen M. Hahn, M.D. Commissioner of Food and Drugs U.S. Food and Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993 Dear Commissioner Hahn: We write regarding the U.S. Food and Drug Administration’s (FDA) troubling decision earlier this week to issue an Emergency Use Authorization (EUA) for convalescent plasma as a treatment for coronavirus disease 2019 (COVID-19).1 Reports suggests that the FDA granted the EUA amid intense political pressure from President Trump and other Administration officials, despite limited evidence of convalescent plasma’s effectiveness as a COVID-19 treatment.2 To help us better understand whether the issuance of the blood plasma EUA was motivated by politics, we request copies of any and all communications between FDA and White House officials regarding the blood plasma EUA.
The authorization will allow health-care providers in the U.S. to use the plasma to treat hospitalized patients with Covid-19.
The FDA’s emergency use authorization came a day after President Trump accused the agency of delaying enrollment in clinical trials for vaccines or therapeutics.
The criticism from Trump and action from the FDA led some scientists to believe the authorization, which came on the eve of the GOP national convention, was politically motivated.
FDA Commissioner Dr. Stephen Hahn is walking back comments on the benefits of convalescent plasma, saying he could have done a better job of explaining the data on its effectiveness against the coronavirus after authorizing it for emergency use over the weekend.
In an interview with Bloomberg’s Drew Armstrong, FDA Commissioner Hahn reiterates that his decision was based on hard evidence and scientific fact, not political pressure. The whole interview is at the link below:
Dr. Hahn corrected his initial statement about 35% of people would be cured by convalescent plasma. In the interview he stated:
I was trying to do what I do with patients, because patients often understand things in absolute terms versus relative terms. And I should’ve been more careful, there’s no question about it. What I was trying to get to is that if you look at a hundred patients who receive high titre, and a hundred patients who received low titre, the difference between those two particular subset of patients who had these specific criteria was a 35% reduction in mortality. So I frankly did not do a good job of explaining that.
FDA colleagues had frank discussion after the statement was made. He is not asking for other people in HHS to retract their statements, only is concerned that FDA has correct information for physicians and patients
Hahn is worried that people will not enroll due to chance they may be given placebo
He gave no opinion when asked if FDA should be an independent agency
For more articles on COVID19 please go to our Coronavirus Portal at
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