This Week in HIV Research: Antibody Being Tested for HIV Prevention, and Differing Results on HCV Treatment in Coinfection
This week, two large clinical trials will test whether a broadly neutralizing antibody injected into humans can prevent HIV infection. Meanwhile, two studies offer differing conclusions on using direct-acting antivirals (DAAs) for individuals living with HIV and hepatitis C. To beat HIV, you have to follow the science!
Two large clinical trials will test whether an investigational broadly neutralizing antibody (bNAb) injected into humans can protect against HIV infection, according to a press release from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH).
The antibody known as VRC01 was discovered by the NIAID Vaccine Research Center in 2010. In laboratory tests, VRC01 prevented up to 90% of known HIV strains from infecting human cells.
Now the AMP (antibody-mediated prevention) Studies will test whether an injection of VRC01 every eight weeks is safe in humans and if it can prevent HIV infection.
The studies will take place in 39 sites across three continents and enroll approximately 4,200 individuals.
"The AMP Studies could have a major impact on the future of HIV prevention and may be especially informative to HIV vaccine research," said NIAID Director Anthony S. Fauci, M.D., according to the study press release.
"Many scientists believe that if a vaccine were developed that elicited broadly neutralizing antibodies in healthy people, it would protect them from HIV infection. The AMP Studies will test this hypothesis by directly giving people the VRC01 antibody."
Study participants will be randomized to receive one of three intravenous-infusion options: VRC01 at 30 mg/kg, VRC01 at 10 mg/kg, or a saline solution placebo. Participants will get a total of 10 injections, once every eight weeks, and follow-up for 20 weeks after that. Because the studies will be double blinded, neither the participants nor the investigators will know which infusion they're receiving.
"The immediate goal of antibody-mediated prevention of HIV is for each VRC01 infusion to have a protective effect that lasts for many weeks," said Myron Cohen, M.D., one of the lead investigators, according to the study press release.
All study participants will receive standard care for HIV prevention, including condoms, lubricant and risk counseling. In addition, participants will have access to pre-exposure prophylaxis (PrEP), if desired.
The first of the AMP Studies, known as HVTN 704/HPTN 085, began on April 6. The second study, known as HVTN 703/HPTN 081, will begin later this spring. The researchers expect final results from both studies in 2022.
Results from two studies presented at the International Liver Congress 2016 show differing conclusions about the efficacy of direct-acting antivirals (DAAs) for individuals living with HIV and hepatitis C (HCV), according to a press release from the European Association for the Study of the Liver (EASL).
In one study, following 1,276 patients in Spain, researchers found that having HIV lowered the rate of cure, or SVR12 (sustained viral response for 12 or more weeks after the end of treatment), by 11% when using interferon-based DAAs, compared with individuals living with HCV only. When using interferon-free DAAs, having HIV lowered the rate of SVR12 by 6%, compared with individuals living with HCV only.
"Our study demonstrates the impact of HIV coinfection on the effectiveness of DAA-based treatment," said lead study author Karin Neukam, M.D., according to the press release.
The second study, in which the U.S. Veterans Health Administration analyzed data from 408 patients living with HCV, found that SVR12 rates were over 88% when using various DAAs. Further analysis controlling for comorbidities did not find any significant negative impact of HIV on achieving SVR12.
"These differing data confirm that the study of HCV treatment in HIV coinfected patients remains an interesting and valuable subject for study," said Laurent Castera, M.D., M.P.H., secretary general of the EASL, according to the press release. "More research is needed to come to a viable resolution so we can provide the best care for these coinfected patients."