Merck released results from a huge clinical trial of a possible successor to Vioxx, saying they support its bid to gain US approval for the drug. But the company also noted some cautions, including increased hypertension.
According to Merck, the 24,000-patient study, when combined with two other trials to create a database of 34,000 patients, showed the rate of confirmed thrombotic cardiovascular events was similar between Arcoxia and older NSAID diclofenac (Novartis’ Voltaren). Arcoxia also caused fewer stomach problems than Voltaren. Merck said in a statement that it will present full results in the fall after review by an independent statistical center. It will then submit them to FDA in response to the agency’s “approvable” letter for Arcoxia, issued in October 2004.
The data were eagerly anticipated by researchers hoping for insights into whether Arcoxia will be approved and whether other Cox-2 drugs like Vioxx and Pfizer’s Celebrex intrinsically pose a heart risk.
Until the full data set is released, however, Steven Nissen, head of cardiology at the Cleveland Clinic, told Forbes he can't draw any conclusions. “There was insufficient information in the press release to know whether or not the drug is free of cardiovascular risk.” Nissen also called into question the study design, saying there is concern of some cardiovascular risk with diclofenac itself, which, if it exists, could have masked such problems in Arcoxia in the study.
Merck raised some other red flags. The incidence of patient dropouts due to hypertension-related adverse events was significantly higher for Arcoxia compared to diclofenac, the company said in a statement. And the incidence of congestive heart failure trended higher among this group, although the difference was not statistically significant.
Merck faces more than 14,000 lawsuits related to Vioxx, which was pulled from shelves in 2004 on concerns it increased heart attack risks.