New Long-Term Data From APPROACH HIV Vaccine Study Shows Promise

Researchers presented at AIDS 2018 encouraging new long-term data from APPROACH, a phase 1/2a study evaluating the safety and immunogenicity of several different HIV vaccine regimens.

Globally, there were 1.8 million new HIV infections in 2016. This demonstrates the need for a prophylactic HIV vaccine, but none currently exist.

The study enrolled nearly 400 HIV-negative adults in the United States, East Africa, South Africa, and Thailand. Healthy, uninfected participants were randomized to receive one of seven vaccine regimens or a placebo, and they were administered Ad26.Mos.HIV double prime at weeks 0 and 12 and a double boost of either Ad26.Mos.HIV or MVA-Mosaic with high- or low-dose aluminium-phosphate adjuvanted gp140 Env protein at weeks 24 and 48.

Previously reported findings from weeks 28 and 52 from the study showed that Ad26.Mos.HIV double prime and Ad26.Mos.
HIV or MVA-Mosaic boost regimens combined with gp140 Env protein were immunogenic and well tolerated. Frank Tomaka,
of Janssen Research & Development, reported week 78 and 96 endpoints, which included immunogenicity and safety/tolerability outcomes.

Participants in all vaccine regimens showed humoral response rates >92% at week 78 (30 weeks after the fourth dose), Dr Tomaka reported. Rates of antibody decay after the fourth vaccination exhibited a regimen-independent decrease in magnitude. Groups boosted with Ad26.Mos.HIV+gp140 Env (high- or low-dose) maintained response rates of 100%.

Follow-up of participants that received Ad26+gp140 Env boosted regimens are planned to continue through 5 years, Dr Tomaka shared.

Data from APPROACH have already helped lead to a proof-of-concept efficacy study in women at risk for HIV. That study, known as Imbokodo, is now taking place in sub-Saharan Africa.—Kara Rosania