Yesterday, an independent advisory panel recommended accelerated Food and Drug Administration (FDA) approval of Merck & Co.'s drug Isentress (raltegravir) for patients fighting drug-resistant strains of HIV. If approved, Isentress would be the first in a new class of AIDS drugs, integrase inhibitors, which seek to prevent HIV from integrating into human DNA during the replication process.
Clinical trials, which lasted 16-24 weeks, involved about 900 patients. In about 600 patients taking Isentress in a cocktail with other AIDS drugs, HIV was suppressed to undetectable levels in the blood of about 62 percent of the individuals. Among the 282 patients taking a standard cocktail plus a placebo, about 34 percent achieved undetectable levels of virus in the blood.
Some in the 11-member panel were concerned with cancers and abnormal tissue growths seen in 13 patients taking Isentress. However, Merck and FDA officials said the rate of malignancies seen among the Isentress group is comparable to the rate among other patients with highly resistant HIV.
Malignancies seen in those taking Isentress included squamous cell carcinoma and lymphoma. None of the placebo patients experienced malignancies during the trial. However, FDA said the difference could be due to chance. An agency analysis suggested there was an unusually low number of malignancies in the placebo group, rather than a high number in the Isentress group. Several panel members recommended Merck conduct a five-year follow-up study of Isentress to confirm its safety.
However, 'overall, based on the data we've seen today, the risk-to-benefit ration seems fairly favorable,' said Dr. Marshall Glesby, a panel member and co-director of Cornell University's HIV Clinical Trials Unit.
FDA is not obliged to accept the panel's advice but usually does. The agency could approve Isentress within a few months.
Los Angeles Times
Date of Publication
Clinical Trials Drug Resistance HIV/AIDS Therapeutic Drugs
Disclaimer: NPIN provides this information as a public service only. The views and information provided about the materials, funding opportunities, and organizations do not necessarily state or reflect those of the U.S. Department of Health and Human Services, CDC, or NPIN.