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Despite heated discussion over whether it works, the FDA has approved Aduhelm, bringing a new ray of hope to the Alzheimer’s patients.

Curator and Reporter: Dr. Premalata Pati, Ph.D., Postdoc

On Monday, 7th June 2021, a controversial new Alzheimer’s Disease treatment was licensed in the United States for the first time in nearly 20 years, sparking calls for it to be made available worldwide despite conflicting evidence about its usefulness. The drug was designed for people with mild cognitive impairment, not severe dementia, and it was designed to delay the progression of Alzheimer’s disease rather than only alleviate symptoms.

Vhttps://youtu.be/atAhUI6OMnsII

The Controversies

The route to FDA clearance for Aducanumab has been bumpy – and contentious.

Though doctors, patients, and the organizations that assist them are in desperate need of therapies that can delay mental decline, scientists question the efficacy of the new medicine, Aducanumab or Aduhelm. In March 2019, two trials were halted because the medications looked to be ineffective. “The futility analysis revealed that the studies were most likely to fail,” said Isaacson of Weill Cornell Medicine and NewYork-Presbyterian. Biogen, the drug’s manufacturer revealed several months later that a fresh analysis with more participants found that individuals who got high doses of Aducanumab exhibited a reduction in clinical decline in one experiment. Patients treated with high-dose Aducanumab had 22% reduced clinical impairment in their cognitive health at 18 months, indicating that the advancement of their early Alzheimer’s disease was halted, according to FDA briefing documents from last year.

When the FDA’s members were split on the merits of the application in November, it was rejected. Three of its advisers went public, claiming that there was insufficient evidence that it worked in a scientific journal. They were concerned that if the medicine was approved, it might reduce the threshold for future approvals, owing to the scarcity of Alzheimer’s treatments.

Dr. Caleb Alexander, a drug safety and effectiveness expert at the Johns Hopkins Bloomberg School of Public Health, was one of the FDA advisers who was concerned that the data presented to the agency was a reanalysis after the experiment was stopped. It was “like the Texas sharpshooter fallacy,” he told the New York Times, “where the sharpshooter blows up a barn and then goes and paints a bullseye around the cluster of holes he loves.”

Some organizations, such as the non-profit Public Citizen’s Health Research Group, claimed that the FDA should not approve Aducanumab for the treatment of Alzheimer’s disease because there is insufficient proof of its efficacy.

The drug is a monoclonal antibody that inhibits the formation of amyloid protein plaques in the brain, which are thought to be the cause of Alzheimer’s disease. The majority of Alzheimer’s medications have attempted to erase these plaques.

Aducanumab appears to do this in some patients, but only when the disease is in its early stages. This means that people must be checked to see if they have the disease. Many persons with memory loss are hesitant to undergo testing because there is now no treatment available.

The few Alzheimer’s medications available appear to have limited effectiveness. When Aricept, also known as Donepezil, was approved more than 20 years ago, there was a major battle to get it. It was heralded as a breakthrough at the time – partly due to the lack of anything else. It has become obvious that it slows mental decline for a few months but makes little effect in the long run.

The findings of another trial for some patients backed up those conclusions.

Biogen submitted a Biologics License Application to the FDA in July 2020, requesting approval of the medicine.

The FDA’s decision has been awaited by Alzheimer’s disease researchers, clinicians, and patients since then.

Support for approval of the drug

Other groups, such as the Alzheimer’s Association, have supported the drug’s approval.

The Alzheimer’s Association‘s website stated on Friday, “This is a critical time, regardless of the FDA’s final judgment. We’ve never been this close to approving an Alzheimer’s drug that could affect the disease’s development rather than just the symptoms. We can keep working together to achieve our goal of a world free of Alzheimer’s disease and other dementias.”

The drug has gotten so much attention that the Knight Alzheimer Disease Research Center at Washington University in St. Louis issued a statement on Friday stating that even if it is approved, “it will still likely take several months for the medication to pass other regulatory steps and become available to patients.”

Biogen officials told KGO-TV on Monday that the medicine will be ready to ship in about two weeks and that they have identified more than 900 facilities across the United States that they feel will be medically and commercially suitable.

Officials stated the corporation will also provide financial support to qualifying patients so that their out-of-pocket payments are as low as possible. Biogen has also pledged not to raise the price for at least the next four years.

Most Medicare customers with supplemental plans, according to the firm, will have a limited or capped co-pay.

Case studies connected to the Drug Approval

Case 1

Ann Lange, one of several Chicago-area clinical trial volunteers who received the breakthrough Alzheimer’s treatment, said,

It really offers us so much hope for a long, healthy life.

Lange, 60, has Alzheimer’s disease, which she was diagnosed with five years ago. Her memory has improved as a result of the monthly infusions, she claims.

She said,

I’d forget what I’d done in the shower, so I’d scribble ‘shampoo, conditioner, face, body’ on the door. Otherwise, I’d lose track of what I’m doing “Lange remarked. “I’m not required to do that any longer.

Case 2

Jenny Knap, 69, has been receiving infusions of the Aducanumab medication for about a year as part of two six-month research trials. She told CNN that she had been receiving treatment for roughly six months before the trial was halted in 2019, and that she had recently resumed treatment.

Knap said,

I can’t say I noticed it on a daily basis, but I do think I’m doing a lot better in terms of checking for where my glasses are and stuff like that.

When Knap was diagnosed with mild cognitive impairment, a clinical precursor to Alzheimer’s disease, in 2015, the symptoms were slight but there.

Her glasses were frequently misplaced, and she would repeat herself, forgetting previous talks, according to her husband, Joe Knap.

Joe added,

We were aware that things were starting to fall between the cracks as these instances got more often

Jenny went to the Lou Ruvo Center for Brain Health at the Cleveland Clinic in Ohio for testing and obtained her diagnosis. Jenny found she was qualified to join in clinical trials for the Biogen medicine Aducanumab at the Cleveland Clinic a few years later, in early 2017. She volunteered and has been a part of the trial ever since.

It turns out that Jenny was in the placebo category for the first year and a half, Joe explained, meaning she didn’t get the treatment.

They didn’t realize she was in the placebo group until lately because the trial was blind. Joe stated she was given the medicine around August 2018 and continued until February 2019 as the trial progressed. The trial was halted by Biogen in March 2019, but it was restarted last October, when Jenny resumed getting infusions.

Jenny now receives Aducanumab infusions every four weeks at the Cleveland Clinic, which is roughly a half-hour drive from their house, with Joe by her side. Jenny added that, despite the fact that she has only recently begun therapy, she believes it is benefiting her, combined with a balanced diet and regular exercise (she runs four miles).

The hope of Aducanumab is to halt the progression of the disease rather than to improve cognition. We didn’t appreciate any significant reduction in her condition, Jenny’s doctor, Dr. Babak Tousi, who headed Aducanumab clinical studies at the Cleveland Clinic, wrote to CNN in an email.

This treatment is unlike anything we’ve ever received before. There has never been a drug that has slowed the growth of Alzheimer’s disease, he stated, Right now, existing medications like donepezil and memantine aid with symptoms but do not slow the disease’s progression.

Jenny claims that the medicine has had no significant negative effects on her.

There was signs of some very minor bleeding in the brain at one point, which was quite some time ago. It was at very low levels, in fact, Joe expressed concern about Jenny, but added that the physicians were unconcerned.

According to Tousi, with repeated therapy, “blood vessels may become leaky, allowing fluid and red blood cells to flow out to the surrounding area,” and “micro hemorrhages have been documented in 19.1% of trial participants who got” the maximal dose of therapy”.

Jenny and Joe’s attitude on the future has improved as a result of the infusions and keeping a healthy lifestyle, according to Joe. They were also delighted to take part in the trial, which they saw as an opportunity to make a positive influence in other people’s lives.

There was this apprehension of what was ahead before we went into the clinical trial, Joe recalled. “The medical aspect of the infusion gives us reason to be optimistic. However, doing the activity on a daily basis provides us with immediate benefits.”

The drug’s final commercialization announcement

Aducanumab, which will be marketed as Aduhelm, is a monthly intravenous infusion that is designed to halt cognitive decline in patients with mild memory and thinking issues. It is the first FDA-approved medication for Alzheimer’s disease that targets the disease process rather than just the symptoms.

The manufacturer, Biogen, stated Monday afternoon that the annual list price will be $56,000. In addition, diagnostic tests and brain imaging will very certainly cost tens of thousands of dollars.

The FDA approved approval for the medicine to be used but ordered Biogen to conduct a new clinical trial, recognizing that prior trials of the medicine had offered insufficient evidence to indicate effectiveness.

Biogen Inc said on Tuesday that it expects to start shipping Aduhelm, a newly licensed Alzheimer’s medicine, in approximately two weeks and that it has prepared over 900 healthcare facilities for the intravenous infusion treatment.

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Recent progress in neurodegenerative diseases and gliomas

Curator: Larry H. Bernstein, MD, FCAP

https://pharmaceuticalintelligence.com/2016/05/28/recent-progress-in-neurodegenerative-diseases-and-gliomas/

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Larry H. Bernstein, MD, FCAP, Reporter, Reposted

Leaders in Pharmaceutical Intelligence

DR ANTHONY MELVIN CRASTO …..FOR BLOG HOME CLICK HERE

http://pharmaceuticalintelligence.com/10/29/2010/larryhbern/Rofecoxib

ROFECOXIB

MK-966, MK-0966, Vioxx

162011-90-7

C17-H14-O4-S
314.3596
\
Percent Composition: C 64.95%, H 4.49%, O 20.36%, S 10.20%
LitRef: Selective cyclooxygenase-2 (COX-2) inhibitor. Prepn: Y. Ducharme et al., WO 9500501; eidem, US5474995 (both 1995 to Merck Frosst).
Therap-Cat: Anti-inflammatory; analgesic.

Rofecoxib /ˌrɒfɨˈkɒksɪb/ is a nonsteroidal anti-inflammatory drug (NSAID) that has now been withdrawn over safety concerns. It was marketed by Merck & Co. to treat osteoarthritisacute pain conditions, and dysmenorrhoea. Rofecoxib was approved by the Food and Drug Administration (FDA) on May 20, 1999, and was marketed under the brand names VioxxCeoxx, and Ceeoxx.

Rofecoxib

Rofecoxib

Rofecoxib gained widespread acceptance among physicians treating patients with arthritis and other conditions causing chronic or acute pain. Worldwide, over 80 million people were prescribed rofecoxib at some time.[1]

On September 30, 2004, Merck withdrew rofecoxib from the market because of concerns about increased risk of heart attack and stroke associated with long-term, high-dosage use. Merck withdrew the drug after disclosures that it withheld information about rofecoxib’s risks from doctors and patients for over five years, resulting in between 88,000 and 140,000 cases of serious heart disease.[2] Rofecoxib was one of the most widely used drugs ever to be withdrawn from the market. In the year before withdrawal, Merck had sales revenue of US$2.5 billion from Vioxx.[3] Merck reserved $970 million to pay for its Vioxx-related legal expenses through 2007, and have set aside $4.85bn for legal claims from US citizens.

Rofecoxib was available on prescription in both tablet-form and as an oral suspension. It was available by injection for hospital use.

 

 Mode of action
 Cyclooxygenase (COX) has two well-studied isoforms, called COX-1 and COX-2.
  • COX-1 mediates the synthesis of prostaglandins responsible for protection of the stomach lining, while
  • COX-2 mediates the synthesis of prostaglandins responsible for pain and inflammation.

prostaglandin PGE2

prostaglandin PGE2

By creating “selective” NSAIDs that inhibit COX-2, but not COX-1, the same pain relief as traditional NSAIDs is offered, but with greatly reduced risk of fatal or debilitating peptic ulcers. Rofecoxib is a selective COX-2 inhibitor, or “coxib”.

Others include Merck’s etoricoxib (Arcoxia), Pfizer’s celecoxib (Celebrex) and valdecoxib (Bextra). Interestingly, at the time of its withdrawal, rofecoxib was the only coxib with clinical evidence of its superior gastrointestinal adverse effect profile over conventional NSAIDs. This was largely based on the VIGOR (Vioxx GI Outcomes Research) study, which compared the efficacy and adverse effect profiles of rofecoxib and naproxen.[4]

Pharmacokinetics

The therapeutic recommended dosages were 12.5, 25, and 50 mg with an approximate bioavailability of 93%.[5][6][7] Rofecoxib crossed the placenta and blood–brain barrier,[5][6][8]and took 1–3 hours to reach peak plasma concentration with an effective half-life (based on steady-state levels) of approximately 17 hours.[5][7][9] The metabolic products are cis-dihydro and trans-dihydro derivatives of rofecoxib[5][9] which are primarily excreted through urine.

Fabricated efficacy studies

On March 11, 2009, Scott S. Reuben, former chief of acute pain at Baystate Medical Center, Springfield, Mass., revealed that data for 21 studies he had authored for the efficacy of the drug (along with others such as celecoxib) had been fabricated in order to augment the analgesic effects of the drugs. There is no evidence that Reuben colluded with Merck in falsifying his data. Reuben was also a former paid spokesperson for the drug company Pfizer (which owns the intellectual property rights for marketing celecoxib in the United States). The retracted studies were not submitted to either the FDA or the European Union’s regulatory agencies prior to the drug’s approval. Drug manufacturer Merckhad no comment on the disclosure.[10]

Adverse drug reactions

VIOXX sample blister pack.jpg

Aside from the reduced incidence of gastric ulceration, rofecoxib exhibits a similar adverse effect profile to other NSAIDs.

Prostaglandin is a large family of lipids. Prostaglandin I2/PGI2/prostacyclin is just one member of it. Prostaglandins other than PGI2 (such as PGE2) also play important roles in vascular tone regulation. Prostacyclin/thromboxane are produced by both COX-1 and COX-2, and rofecoxib suppresses just COX-2 enzyme, so there is no reason to believe that prostacyclin levels are significantly reduced by the drug. And there is no reason to believe that only the balance between quantities of prostacyclin and thromboxane is the determinant factor for vascular tone.[11] Indeed Merck has stated that there was no effect on prostacyclin production in blood vessels in animal testing.[12] Other researchers have speculated that the cardiotoxicity may be associated with maleic anhydride metabolites formed when rofecoxib becomes ionized under physiological conditions. (Reddy & Corey, 2005)

 Adverse cardiovascular events

VIGOR study and publishing controversy

The VIGOR (Vioxx GI Outcomes Research) study, conducted by Bombardier, et al., which compared the efficacy and adverse effect profiles of rofecoxib and naproxen, had indicated a significant 4-fold increased risk of acute myocardial infarction (heart attack) in rofecoxib patients when compared with naproxen patients (0.4% vs 0.1%, RR 0.25) over the 12 month span of the study. The elevated risk began during the second month on rofecoxib. There was no significant difference in the mortality from cardiovascular events between the two groups, nor was there any significant difference in the rate of myocardial infarction between the rofecoxib and naproxen treatment groups in patients without high cardiovascular risk. The difference in overall risk was by the patients at higher risk of heart attack, i.e. those meeting the criteria for low-dose aspirin prophylaxis of secondary cardiovascular events (previous myocardial infarction, angina, cerebrovascular accidenttransient ischemic attack, or coronary artery bypass).

Merck’s scientists interpreted the finding as a protective effect of naproxen, telling the FDA that the difference in heart attacks “is primarily due to” this protective effect (Targum, 2001). Some commentators have noted that naproxen would have to be three times as effective as aspirin to account for all of the difference (Michaels 2005), and some outside scientists warned Merck that this claim was implausible before VIGOR was published.[13] No evidence has since emerged for such a large cardioprotective effect of naproxen, although a number of studies have found protective effects similar in size to those of aspirin.[14][15] Though Dr. Topol’s 2004 paper criticized Merck’s naproxen hypothesis, he himself co-authored a 2001 JAMA article stating “because of the evidence for an antiplatelet effect of naproxen, it is difficult to assess whether the difference in cardiovascular event rates in VIGOR was due to a benefit from naproxen or to a prothrombotic effect from rofecoxib.” (Mukherjee, Nissen and Topol, 2001.)

The results of the VIGOR study were submitted to the United States Food and Drug Administration (FDA) in February 2001. In September 2001, the FDA sent a warning letter to the CEO of Merck, stating, “Your promotional campaign discounts the fact that in the VIGOR study, patients on Vioxx were observed to have a four to five fold increase in myocardial infarctions (MIs) compared to patients on the comparator non-steroidal anti-inflammatory drug (NSAID), Naprosyn (naproxen).”[16] This led to the introduction, in April 2002, of warnings on Vioxx labeling concerning the increased risk of cardiovascular events (heart attack and stroke).

Months after the preliminary version of VIGOR was published in the New England Journal of Medicine, the journal editors learned that certain data reported to the FDA were not included in the NEJM article. Several years later, when they were shown a Merck memo during the depositions for the first federal Vioxx trial, they realized that these data had been available to the authors months before publication. The editors wrote an editorial accusing the authors of deliberately withholding the data.[17] They released the editorial to the media on December 8, 2005, before giving the authors a chance to respond. NEJM editor Gregory Curfman explained that the quick release was due to the imminent presentation of his deposition testimony, which he feared would be misinterpreted in the media. He had earlier denied any relationship between the timing of the editorial and the trial. Although his testimony was not actually used in the December trial, Curfman had testified well before the publication of the editorial.[18]

The editors charged that “more than four months before the article was published, at least two of its authors were aware of critical data on an array of adverse cardiovascular events that were not included in the VIGOR article.” These additional data included three additional heart attacks, and raised the relative risk of Vioxx from 4.25-fold to 5-fold. All the additional heart attacks occurred in the group at low risk of heart attack (the “aspirin not indicated” group) and the editors noted that the omission “resulted in the misleading conclusion that there was a difference in the risk of myocardial infarction between the aspirin indicated and aspirin not indicated groups.” The relative risk for myocardial infarctions among the aspirin not indicated patients increased from 2.25 to 3 (although it remained statitistically insignificant). The editors also noted a statistically significant (2-fold) increase in risk for serious thromboembolic events for this group, an outcome that Merck had not reported in the NEJM, though it had disclosed that information publicly in March 2000, eight months before publication.[19]

The authors of the study, including the non-Merck authors, responded by claiming that the three additional heart attacks had occurred after the prespecified cutoff date for data collection and thus were appropriately not included. (Utilizing the prespecified cutoff date also meant that an additional stroke in the naproxen population was not reported.) Furthermore, they said that the additional data did not qualitatively change any of the conclusions of the study, and the results of the full analyses were disclosed to the FDA and reflected on the Vioxx warning label. They further noted that all of the data in the “omitted” table were printed in the text of the article. The authors stood by the original article.[20]

NEJM stood by its editorial, noting that the cutoff date was never mentioned in the article, nor did the authors report that the cutoff for cardiovascular adverse events was before that for gastrointestinal adverse events. The different cutoffs increased the reported benefits of Vioxx (reduced stomach problems) relative to the risks (increased heart attacks).[19]

Some scientists have accused the NEJM editorial board of making unfounded accusations.[21][22] Others have applauded the editorial. Renowned research cardiologist Eric Topol,[23] a prominent Merck critic, accused Merck of “manipulation of data” and said “I think now the scientific misconduct trial is really fully backed up”.[24] Phil Fontanarosa, executive editor of the prestigious Journal of the American Medical Association, welcomed the editorial, saying “this is another in the long list of recent examples that have generated real concerns about trust and confidence in industry-sponsored studies”.[25]

On May 15, 2006, the Wall Street Journal reported that a late night email, written by an outside public relations specialist and sent to Journal staffers hours before the Expression of Concern was released, predicted that “the rebuke would divert attention to Merck and induce the media to ignore the New England Journal of Medicine‘s own role in aiding Vioxx sales.”[26]

“Internal emails show the New England Journal’s expression of concern was timed to divert attention from a deposition in which Executive Editor Gregory Curfman made potentially damaging admissions about the journal’s handling of the Vioxx study. In the deposition, part of the Vioxx litigation, Dr. Curfman acknowledged that lax editing might have helped the authors make misleading claims in the article.” The Journal stated that NEJM‘s “ambiguous” language misled reporters into incorrectly believing that Merck had deleted data regarding the three additional heart attacks, rather than a blank table that contained no statistical information; “the New England Journal says it didn’t attempt to have these mistakes corrected.”[26]

APPROVe study

In 2001, Merck commenced the APPROVe (Adenomatous Polyp PRevention On Vioxx) study, a three-year trial with the primary aim of evaluating the efficacy of rofecoxib for theprophylaxis of colorectal polypsCelecoxib had already been approved for this indication, and it was hoped to add this to the indications for rofecoxib as well. An additional aim of the study was to further evaluate the cardiovascular safety of rofecoxib.

The APPROVe study was terminated early when the preliminary data from the study showed an increased relative risk of adverse thrombotic cardiovascular events (includingheart attack and stroke), beginning after 18 months of rofecoxib therapy. In patients taking rofecoxib, versus placebo, the relative risk of these events was 1.92 (rofecoxib 1.50 events vs placebo 0.78 events per 100 patient years). The results from the first 18 months of the APPROVe study did not show an increased relative risk of adverse cardiovascular events. Moreover, overall and cardiovascular mortality rates were similar between the rofecoxib and placebo populations.[28]

In summary, the APPROVe study suggested that long-term use of rofecoxib resulted in nearly twice the risk of suffering a heart attack or stroke compared to patients receiving a placebo.

Other studies

Several very large observational studies have also found elevated risk of heart attack from rofecoxib. For example, a recent retrospective study of 113,000 elderly Canadians suggested a borderline statistically significant increased relative risk of heart attacks of 1.24 from Vioxx usage, with a relative risk of 1.73 for higher-dose Vioxx usage. (Levesque, 2005). Another study, using Kaiser Permanente data, found a 1.47 relative risk for low-dose Vioxx usage and 3.58 for high-dose Vioxx usage compared to current use of celecoxib, though the smaller number was not statistically significant, and relative risk compared to other populations was not statistically significant. (Graham, 2005).

Furthermore, a more recent meta-study of 114 randomized trials with a total of 116,000+ participants, published in JAMA, showed that Vioxx uniquely increased risk of renal (kidney) disease, and heart arrhythmia.[31]

Other COX-2 inhibitors

Any increased risk of renal and arrhythmia pathologies associated with the class of COX-2 inhibitors, e.g. celecoxib (Celebrex), valdecoxib (Bextra), parecoxib (Dynastat),lumiracoxib, and etoricoxib is not evident,[31] although smaller studies[32][33] had demonstrated such effects earlier with the use of celecoxib, valdecoxib and parecoxib.

Nevertheless, it is likely that trials of newer drugs in the category will be extended in order to supply additional evidence of cardiovascular safety. Examples are some more specific COX-2 inhibitors, including etoricoxib (Arcoxia) and lumiracoxib (Prexige), which are currently (circa 2005) undergoing Phase III/IV clinical trials.

Besides, regulatory authorities worldwide now require warnings about cardiovascular risk of COX-2 inhibitors still on the market. For example, in 2005, EU regulators required the following changes to the product information and/or packaging of all COX-2 inhibitors:[34]

  • Contraindications stating that COX-2 inhibitors must not be used in patients with established ischaemic heart disease and/or cerebrovascular disease (stroke), and also in patients with peripheral arterial disease
  • Reinforced warnings to healthcare professionals to exercise caution when prescribing COX-2 inhibitors to patients with risk factors for heart disease, such as hypertension, hyperlipidaemia (high cholesterol levels), diabetes and smoking
  • Given the association between cardiovascular risk and exposure to COX-2 inhibitors, doctors are advised to use the lowest effective dose for the shortest possible duration of treatment

Other NSAIDs

Since the withdrawal of Vioxx it has come to light that there may be negative cardiovascular effects with not only other COX-2 inhibitiors, but even the majority of other NSAIDs. It is only with the recent development of drugs like Vioxx that drug companies have carried out the kind of well executed trials that could establish such effects and these sort of trials have never been carried out in older “trusted” NSAIDs such as ibuprofendiclofenac and others. The possible exceptions may be aspirin and naproxen due to their anti-platelet aggregation properties.

Withdrawal

Due to the findings of its own APPROVe study, Merck publicly announced its voluntary withdrawal of the drug from the market worldwide on September 30, 2004.[35]

In addition to its own studies, on September 23, 2004 Merck apparently received information about new research by the FDA that supported previous findings of increased risk of heart attack among rofecoxib users (Grassley, 2004). FDA analysts estimated that Vioxx caused between 88,000 and 139,000 heart attacks, 30 to 40 percent of which were probably fatal, in the five years the drug was on the market.[36]

On November 5, the medical journal The Lancet published a meta-analysis of the available studies on the safety of rofecoxib (Jüni et al., 2004). The authors concluded that, owing to the known cardiovascular risk, rofecoxib should have been withdrawn several years earlier. The Lancet published an editorial which condemned both Merck and the FDA for the continued availability of rofecoxib from 2000 until the recall. Merck responded by issuing a rebuttal of the Jüni et al. meta-analysis that noted that Jüni omitted several studies that showed no increased cardiovascular risk. (Merck & Co., 2004).

In 2005, advisory panels in both the U.S. and Canada encouraged the return of rofecoxib to the market, stating that rofecoxib’s benefits outweighed the risks for some patients. The FDA advisory panel voted 17-15 to allow the drug to return to the market despite being found to increase heart risk. The vote in Canada was 12-1, and the Canadian panel noted that the cardiovascular risks from rofecoxib seemed to be no worse than those from ibuprofen—though the panel recommended that further study was needed for all NSAIDs to fully understand their risk profiles. Notwithstanding these recommendations, Merck has not returned rofecoxib to the market.[37]

In 2005, Merck retained Debevoise & Plimpton LLP to investigate Vioxx study results and communications conducted by Merck. Through the report, it was found that Merck’s senior management acted in good faith, and that the confusion over the clinical safety of Vioxx was due to the sales team’s overzealous behavior. The report that was filed gave a timeline of the events surrounding Vioxx and showed that Merck intended to operate honestly throughout the process. Any mistakes that were made regarding the mishandling of clinical trial results and withholding of information was the result of oversight, not malicious behavior….The report was published in February 2006, and Merck was satisfied with the findings of the report and promised to consider the recommendations contained in the Martin Report. Advisers to the US Food and Drug Administration (FDA) have voted, by a narrow margin, that it should not ban Vioxx — the painkiller withdrawn by drug-maker Merck.

They also said that Pfizer’s Celebrex and Bextra, two other members of the family of painkillers known as COX-2 inhibitors, should remain available, despite the fact that they too boost patients’ risk of heart attack and stroke. url = http://www.nature.com/drugdisc/news/articles/433790b.html The recommendations of the arthritis and drug safety advisory panel offer some measure of relief to the pharmaceutical industry, which has faced a barrage of criticism for its promotion of the painkillers. But the advice of the panel, which met near Washington DC over 16–18 February, comes with several strings attached.

For example, most panel members said that manufacturers should be required to add a prominent warning about the drugs’ risks to their labels; to stop direct-to-consumer advertising of the drugs; and to include detailed, written risk information with each prescription. The panel also unanimously stated that all three painkillers “significantly increase the risk of cardiovascular events”.

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