FDA Approves Prezista for Use in Treatment Naive Individuals

FDA on Tuesday approved Johnson & Johnson's protease inhibitor Prezista for use by people who have never taken antiretroviral drugs in the past, the Wall Street Journal reports. FDA in 2006 approved Prezista for HIV-positive people who had developed resistance to other drugs. The agency also granted tentative approval for the drug as part of FDA's accelerated approval mechanism, which allows drugs to be sold while further studies are conducted. J&J obtained full approval for Prezista after submitting studies to FDA through this mechanism (Corbett Dooren, Wall Street Journal, 10/23).

According to J&J, patients beginning HIV treatment should take Prezista -- generically known as darunavir -- in combination with ritonavir. Ritonavir -- sold by Abbott Laboratories under the brand name Norvir -- works in combination with Prezista by slowing down the body's processing of the drug, Reuters reports (Reuters, 10/22). As a protease inhibitor, Prezista works by blocking a protein that HIV requires for replication. Treatment-naive HIV-positive people are recommended to take two 400 mg tablets of Prezista with 100 mg of ritonavir twice daily, and patients who have previously taken other HIV medications are recommended to take 600 mg of Prezista twice daily. J&J will discontinue the production of a 300 mg tablet following a decline in demand. According to the company, the wholesale price of the drug is about $740 monthly.

Glenn Mattes, president of J&J's Tibotec Therapeutics, said FDA approval of Prezista for newly diagnosed HIV-positive people "is a significant expansion of our ability to reach the entire population of patients who should be treated with a protease inhibitor." According to the AP/Boston Globe, during a study that compared Prezista with Kaletra -- a similar drug produced by Abbott -- 84% of patients treated with Prezista had HIV viral loads drop to an undetectable level, compared with 78% of patients taking Kaletra. However, this difference was not considered statistically significant (AP/Boston Globe, 10/22). Side effects of Prezista include diarrhea, headache, nausea, skin rash and, in some cases, hepatitis and liver failure (Reuters, 10/22).