July 16, 2012 |
HIV Prevention Pill Okayed by Food & Drug Administration |
WASHINGTON, D.C.—Today, the federal Food and Drug Administration put its stamp of approval on Truvada, a pill combining two anti-retroviral drugs, as a method to decrease infection by the human immunodeficiency virus, better known as HIV. The drug will now be available by prescription to those who wish to decrease their likelihood of becoming HIV-infected. The drug, produced by Gilead Sciences of Foster City, Calif., has been used for treatment of HIV-infected persons since 2004, but a recently-completed three-year clinical trial involving 2,499 HIV-negative men and transgendered women who had sex with men and exhibited high-risk behavior for HIV infection—that is, they used condoms inconsistently if at all; didn't know their partner's HIV status; had a high number of sex partners; and many of whom were prostitutes—showed that the drug was effective in reducing thr risk of HIV infection by 42 percent compared with study participants receiving a placebo. The drug was also found to be 75 percent effective in preventing transmission of the disease from a known infected partner to a known uninfected one. Truvada's approval could have a significant effect on the adult entertainment community, whose performers test for HIV infection at least once every 28 days (and soon possibly as often as every 14 days), and indeed, the FDA "strongly recommends against" the drug's use in "individuals with unknown or positive HIV status." In order to benefit from the drug, it's necessary to take it every day, at a cost of up to $14,000 per year, according to an article in USA Today. By comparison, when the drug was tested in Africa, Gilead sold a year's worth of the drug at deep discount prices ranging between $100 and $480, depending on the country. This was still unaffordable for many, where the average person survives on just $2 per day. In advance of the International AIDS Conference, scheduled to be held in D.C. July 22-27, AIDS Healthcare Foundation (AHF) described the FDA's action in approving the drug "reckless," deemed Gilead's and others' studies to be "dubious research," and claimed that another recent study had "showed one key component of Truvada [to be] associated with significant risk of kidney damage and disease that increases over time." "The FDA's approval of Gilead's Truvada as a form of HIV prevention today without any requirement for HIV testing is completely reckless and a move that will ultimately set back years of HIV prevention efforts," said AHF president Michael Weinstein. However, the FDA disagreed with that assessment, stating that, "Serious adverse events in general, as well as those specifically related to kidney or bone toxicity, were uncommon... The most common side effects reported with Truvada included diarrhea, nausea, abdominal pain, headache, and weight loss." Indeed, AHF's claim of kidney damage was debunked several months ago, leading one to wonder whether their opposition to Truvada's approval reflects a dedication to preventing HIV or to lining the organization's own pockets with future contributions. But since Truvada is not a cure for HIV, the FDA and AHF are certainly wise to call for HIV testing before beginning use of the drug—and another recent FDA approval may work against that recommended testing regimen. About two weeks ago, the FDA approved a home test for HIV called OraQuick, which is often described as a "rapid HIV test." OraQuick tests for the antibodies which HIV infection eventually produces in the infected person's blood, and is therefore of little use to adult performers, since it may take three to six months for those antibodies to be produced in detectable levels—a delay that would be deadly for adult content producers. Indeed, Elliot Cowan, a Ph.D. in the FDA's Division of Emerging and Tranfusion-Transmitted Diseases, warned that even with a positive result with the OraQuick test, "further testing is needed to confirm your HIV status. Look at this as a first step in HIV testing. No test is perfect—there will be false positives. Clinical studies for self-testing have shown that the OraQuick test will produce one false positive result out of about every 5,000 tests in uninfected individuals." Of more concern, however, would be a negative OraQuick result. "The test is not reliable at detecting HIV infection until at least three months after infection," Cowan stated. "In addition, even after three months, there can also be false negatives. Clinical studies by untrained consumers showed that the OraQuick test will produce about one false negative result out of every 12 tests performed in HIV infected individuals." Considering that the FDA estimates that 1.2 million Americans currently are HIV-infected, that an estimated 240,000 are "HIV carriers" who are unaware of their infectes status, and that for the past 15 years, the number of HIV-infected persons has grown at the rate of 50,000 new infections per year, the at-home test may be of use to them—and should definitely be tried by persons wishing to become adult entertainment sexual performers if no better test is available to them. As part of its approval, the FDA is requiring Gilead to conduct further tests, including collecting virus samples from those who become HIV-infected while taking Truvada and to evaluate those samples for the presence of resistance to the drug. Also, the company is required to collect data on pregnancy outcomes for women who become pregnant while taking Truvada, and to conduct a trial to evaluate the correlation between adherence to the drug regimen and its relationship to adverse events, the risk of seroconversion (HIV antibody development), and resistance development in those who do form HIV antibodies.
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