4 Significant Discoveries Revealed At This Week’s International AIDS Conference

Dr. Lisa Sterman holds up a Truvada pill (PrEP). CREDIT: AP PHOTO/JEFF CHIU
Dr. Lisa Sterman holds up a Truvada pill (PrEP). CREDIT: AP PHOTO/JEFF CHIU

The 20th International AIDS Conference, which concludes Friday, may have been marred by the loss of several scholars and activists on Malaysian Airlines Flight 17, but it still delivered some good news in the fight against the planet’s HIV epidemic. Here are a few of the key discoveries revealed at this week’s conference.

PrEP Really Works At Preventing Infection If Taken Regularly

A new study called iPrEx OLE has further confirmed the effectiveness of PrEP (pre-exposure prophylaxis), HIV medication taken by people who do not currently carry the virus to prevent them from being infected. When taken regularly, PrEP is highly effective at preventing HIV infection.

The primary obstacle PrEP faces is whether a person takes it regularly. It’s prescribed as a daily regimen, and the study found it to be 100 percent effective among people who took it at least four times a week. Individuals who only took 2–3 doses per week had an efficacy rate of 84 percent, while those who took it less often were no more protected from the virus than if they weren’t taking it at all. When taken properly, it seems PrEP approaches perfection in preventing the transmission of HIV.

The same study also found that taking PrEP did not lead users to take more risks during sex, as some detractors have claimed. Throughout the study, participants actually had lower rates of unprotected anal sex and fewer sexual partners.

Condoms Could Soon Come With Anti-HIV Gel

The Australian biotech firm Starpharma has developed an antiviral compound called VivaGel that it hopes to introduce to condom lube to help kill HIV and some other sexually transmitted infections, reducing the risk of transmission. Tests have suggested it can deactivate up to 99.9 percent of virus cells.

VivaGel is still undergoing trials in the U.S., so it’s not available yet, and there may be good reason to exercise caution. Other studies have found that the substance can be an irritant to the body, which would attract the very white blood cells most susceptible to HIV infection. Still, given condoms always have the possibility of failing, VivaGel could help compensate by further reducing the risk of infection.

Cancer Drugs Could Kick HIV Out Of Hiding In Infected Cells

Danish researchers at Aarhus University revealed this week that they’ve had some success in using anti-cancer drugs to kick HIV out of hiding, making the virus more easily identified in blood and vulnerable to attack.

When patients use antiretroviral therapy to reduce the number of infected cells, some undetectable quantity of the virus remains. This “reservoir” of cells can take hold of the immune system and begin replicating the virus again if the patient ever stops taking their medication. But the procedure being studied by the Danish researchers would allow even those sleeper cells to be identified, but more would need to be done after that. Unfortunately, the patients’ immune systems did not attack the identified cells, and the procedure did not significantly reduce the number of infected cells even after they were identified.

Even if this next hurdle was overcome, it’s unclear if the procedure could truly ever remove the virus from a person’s body. If even one cell were left in hiding, it could be enough to allow HIV to thrive again.

HIV Could Be Destroyed Without Harm To The Infected Cells

At Temple University, researchers took a different approach to attacking HIV head on. They have created a protein combo that is capable of targeting and attaching itself to the HIV in a cell’s DNA. It cuts out the infected part, allowing the cell to repair itself and become healthy again.

The “gene surgery” technique is still years away from successful human implementation. Though it’s proven effective on human cells, animal testing is just now beginning. Researchers will have to develop a method to administer the treatment in a way that reaches every infected cell and that can individualized to combat different mutations of the virus. The technique could ultimately prove useful in fighting other viruses.

Despite the exciting news in HIV treatment and prevention, the U.S. Centers for Disease Control and Prevention announced this week HIV diagnoses for men who have sex with men (MSM) continue to climb. Between 2001 and 2011, diagnoses for MSM aged 13–24 increased by 132.5 percent — despite the fact that the overall diagnosis rate dropped by a third over the same time period.