Tenofovir microbicide gel will be reviewed for approval as quickly as possible, the US Food and Drug Administration has confirmed.
The CAPRISA 004 study, presented at the XVII International AIDS Conference in Vienna in July, showed that use of a vaginal gel containing the antiretroviral drug tenofovir reduced the risk of HIV infection by 39% for women who received the product in a placebo-controlled study conducted in South Africa.
CONRAD, a non-profit microbicide and contraceptive technology research organisation announced on Monday that the FDA has agreed to begin a fast-track review procedure as soon as full data from the CAPRISA 004 study are ready for submission.
With Fast Track designation, a new drug application (NDA) can be submitted as a “rolling review”, which allows a clinical trial sponsor to submit completed sections of its NDA for review by the FDA, rather than waiting until every section of the application is completed before the entire application can be reviewed.
The FDA requires two well-controlled studies to approve a product. The FDA has also confirmed that if the study shows a positive protective effect of 1% tenofovir gel, it will accept the results of the VOICE study as soon as these are available.
The VOICE study (Vaginal and Oral Interventions to Control the Epidemic) is a placebo-controlled comparison of oral tenofovir or oral tenofovir/FTC with 1% tenofovir vaginal gel in approximately 5000 women in Zimbabwe, Uganda, South Africa and Malawi. Results from this study are due in early 2013.
However, the FDA has stated that additional safety data on adolescents would be needed and that information on in vivo drug interaction studies with commonly used vaginal products should be obtained. The FDA will ultimately need data on post-menopausal women too.
Once the FDA has received all the data has asked for, it must complete its review of a Fast Track submission within six months. This means that a decision on licesning approval might be reached in early 2014.
Since much of the clinical work on 1% tenofovir gel is being conducted in South Africa, FDA officials indicated that they can work through the FDA’s Office of International Programs with the goal of co-ordinating the data and review processes with the South African Medicines Control Council.
Henry Gabelnick of CONRAD said that the organisation was already working with a South African manufacturer to develop a public-private partnership to produce the tenofovir gel in South Africa, and to develop distribution systems.
The Global Campaign for Microbicides welcomed the announcement. "We believe it will have a strong impact on future trials, action by other country regulators, and GCM’s own advocacy. Most importantly, it offers hope for millions of women."