Sun Oct 17, 2004 09:28 PM ET
NEW YORK, Oct 17 (Reuters) - Drug firm Merck & Co. (MRK.N: Quote, Profile, Research) will present data this week showing that an experimental arthritis drug, Arcoxia, a treatment in the same class as its recently withdrawn Vioxx, showed no significant difference in the number of serious side effects than those treated with a common medicine called diclofenac.
A trial of 7,111 patients with osteoarthritis showed that patients treated with Arcoxia for up to 16.5 months -- with a mean duration of 9 months -- had no higher risk of serious, drug-related side effects than those in the control group, according to a summary of the data on the Web site of the American College of Rheumatology (
www.rheumatology.org).
The trial has been closely watched as the withdrawal of Vioxx has cast doubt over the entire class of drugs, known as COX-II inhibitors, of which it was a member.
Those include Pfizer Inc.'s Bextra and Celebrex and Novartis AG's experimental drug Prexige.
Vioxx was withdrawn after patients taking it for at least 18 months suffered twice as many heart attacks or strokes as those taking a placebo.
The risk, hinted at in earlier trials, was definitively proven in a 2,600-patient trial to see if Vioxx could prevent the recurrence of colon polyps.
Merck has filed for U.S. approval of Arcoxia but analysts doubt it will be approved by the U.S. Food and Drug Administration, which is expected to make a ruling by the end of the month. That's partly because Merck has only tested the drug against a placebo group for 12 weeks.
The latest trial does not compare the drug to a placebo. Even so, it could provide an important indicator of the drug's medium-term safety.
The company is conducting a bigger, 20,000-patient trial that also compares Arcoxia to diclofenac, which is due to be completed in 2006.
Analysts have said they believe the FDA will wait until the completion of that trial before deciding whether to approve the drug as the problems with Vioxx did not clearly show up until after 18 months.
The main goal of the trial was to compare the rate of discontinuation from the trial because of gastro-intestinal problems, and it showed that patients on Arcoxia had a significantly smaller dropout rate than with those on diclofenac.