HIV Drug Therapy: Efavirenz Compromises Hormonal Contraceptive Implant

The widely prescribed non-nucleoside reverse transcriptase inhibitor (NNRTI) efavirenz substantially reduces levels of the hormonal contraceptive levonorgestrel, a component of a progesterone contraceptive implant widely used in developing countries, according to findings from a study conducted in Uganda presented this week at the HIV Drug Therapy Glasgow conference.


HIV R4P: Vaginal Rings Show Promise for HIV Prevention

A silicone intravaginal ring that releases the antiretroviral drugs dapivirine and darunavir was shown to reach levels expected to be effective in vaginal and cervical fluid and tissues in monkeys, researchers reported at the HIV Research for Prevention meeting last week in Cape Town. A related study found that a single ring can potentially serve multiple purposes, preventing HIV, genital herpes, HPV, and pregnancy.


HIV R4P: Research for Prevention Conference Opens with Real Hope for HIV Vaccine

"There’s only one Berlin Patient still. But by this time next year he will at least be joined by 40-50 Portland monkeys." These were the words of vaccine researcher Louis Picker, summarizing in quotable form why the outlook for the development of an effective HIV vaccine is brighter than it has been for years, in a satellite session in advance of the HIV Research for Prevention conference (R4P) in Cape Town, South Africa.


HIV R4P: Injectable Rilpivirine Shows Promise, May Work Better for Anal than Vaginal Sex

A Phase 1 dose-finding and safety study in humans of TMC278-LA, a long-acting, injectable formation of the antiretroviral drug rilpivirine, found that a single 1200 mg dose could produce sustained drug levels in rectal tissues that could offer protection against HIV for 3 months, and did in fact suppress viral replication in so-called explants (biopsies of rectal mucosal cells) for that length of time. However -- and to the surprise of researchers presenting this study at the HIV Research for Prevention conference last week in Cape Town -- drug levels in vaginal and cervical cells were only about half of those seen in rectal cells, and viral replication was not suppressed in vaginal and cervical biopsies taken from women given TMC278-LA.


HIV R4P: Injectable Cabotegravir Makes Progress, Doubts About Injectable Rilpivirine

Researchers have determined the dose of an injectable formulation of the integrase inhibitor cabotegravir (formerly GSK1256744) that will be taken into efficacy trials to see if it can be used for pre-exposure prophylaxis (PrEP). Progress on an injectable formulation of another drug, rilpivirine, received a setback, however, when animal studies showed it lost its efficacy against viral challenge after only 18-21 days, researchers reported at the HIV Research for Prevention meeting this week in Cape Town.


Coverage of HIV Research for Prevention Conference (HIV R4P) coverage of the HIV Research for Prevention Conference, October 28-31, in Cape Town.

This conference -- combining the previous HIV Vaccines and Microbicides meetings -- includes all aspects of HIV prevention including experimental vaccines, microbicide gels and rings, and pre-exposure prophylaxis (PrEP).

Full listing of coverage by topic

HIV R4P website



HIV R4P: Tenofovir Gel Associated with Lower Herpes Simplex Risk for Women

The risk of acquiring herpes simplex virus type 2 (HSV-2) was reduced by 46% among women who regularly used a vaginal gel containing tenofovir, according to a secondary analysis of the VOICE trial presented at the HIV Research for Prevention conference (R4P) this week in Cape Town. There was no significant difference in the age, marital status, country, practice of anal sex, HIV status, or hormonal contraceptive use between women who acquired HSV-2 and those who did not.