[Reposted from the
O'Neill Institute Blog]
The Food and Drug Administration
announced today
its approval of tenofovir-emtricitabine (aka Truvada) for HIV
prevention. Truvada, which has been approved since 2004 for use in HIV
treatment, is now approved for use as preexposure prophylaxis (“PrEP”)–a
strategy in which an HIV-negative person uses an antiretroviral drug
(in this case a daily pill) to reduce the risk of acquiring HIV from
behaviors such as unprotected sex. [More info on this strategy from
CDC and
AVAC.]
Although the approval had been anticipated–an advisory committee
recommended approval in May–there had remained questions about the parameters of the approval:
(1) Populations: clinical trials have demonstrated clear (albeit partial) efficacy of Truvada among
men who have sex with men and
heterosexual couples in which one partner is HIV positive and the other is negative,
leading the advisory committee to vote overwhelmingly to approve for
these populations. However, the data among heterosexual women are more
mixed. As a result, the advisory committee’s vote on whether to approve
for “other individuals at risk for acquiring HIV through sexual
activity”
was a close call at 12-8. Today,
FDA
announced that Truvada would be approved for anyone “at high risk of
HIV infection and who may engage in sexual activity with HIV-infected
partners”–a win for women’s health advocates who supported broader
access, citing the vulnerability of many women to HIV exposure from male
partners who refuse to use condoms.
(2) Risk mitigation: the
FDA‘s decision was originally fast-tracked with a target date of June 15, but
pushed back with the announcement that the
FDA
would be considering new materials on the Risk Evaluation Management
Strategy (REMS) from the drug’s manufacturer. This topic had received
extensive discussion among the advisory committee, and for those
skeptical of PrEP as a public health intervention, it was key: concerns
about the drug’s safety (risks of kidney damage and bone density loss)
and drug resistance (among those who become HIV infected and continue
taking Truvada instead of full-on ARV therapy) had led some to suggest
strict limitations to control access, e.g. only to patients who could
show a negative HIV test. Instead, the
FDA‘s
announcement described a REMS based on education for providers and
patients, explaining that stricter limits would have added “unnecessary
burdens to health care professionals and patients.”
Less strict requirements may be important for patients with less
consistent access to health systems, many of whom may face elevated HIV
risk. The CDC is expected to issue new clinical practice guidelines for
PrEP, and the debate over how best to roll out this
intervention–safely, effectively, and equitably–will certainly continue.
