Phase 2 clinical trial launched in Thailand to evaluate IL-15 agonist as therapy to reduce HIV reservoir

Reviewed by Emily Henderson, B.Sc.Apr 8 2021

The U.S. Military HIV Research Program (MHRP) at the Walter Reed Army Institute of Research last week launched a Phase 2 clinical trial in Thailand to evaluate an interleukin-15 (IL-15) superagonist, ImmunityBio's Anktiva^® (also called N-803), administered during acute HIV infection as an experimental therapy to target establishment of the HIV reservoir at a very early stage.

The trial's participants are identified through MHRP's RV254 acute HIV infection cohort, which identifies individuals in the earliest post-infection stages. Volunteers will receive their first dose of IL-15 agonist and initiate antiretroviral therapy (ART) within days of the diagnosis of acute HIV infection.

A critical barrier to curing HIV is the reservoir of latent virus that remains hidden and infects cells throughout the body, and previous studies have shown that the reservoir is established very early in HIV infection.

We hope that administering an IL-15 agonist alongside traditional ART will reduce the HIV reservoir in lymphoid tissues. Ultimately this trial will help inform a strategy towards inducing long-term HIV remission."

Dr. Denise Hsu, MHRP's Associate Director of Therapeutics

In previous preclinical and clinical testing, ImmunityBio's Anktiva was shown to boost immune activation of natural killer cells and CD8+ T cells.

The study, called RV550, will enroll 15 participants who will receive three total doses of Anktiva, at weeks 0, 3 and 6 of the study. Researchers will compare levels of HIV RNA and DNA in lymph node samples pre- and post-treatment and evaluate the therapy's effects on CD8+ T and natural killer immune cells.

The study is conducted at The Thai Red Cross AIDS Research Centre in Bangkok.

"We're grateful to the many committed volunteers in this study and the larger acute infection cohort, and also to our dedicated clinical study team," said Dr. Kiat Ruxrungtham, professor of medicine at Chulalongkorn University and principal investigator of the trial. "Their contributions are vital to ongoing research to find a cure for HIV."

The RV254 acute HIV infection cohort provides insight into critical early days after infection. The cohort serves as a foundation to help MHRP researchers conduct investigations into long term remission of HIV and tools that can serve to accomplish "functional cure," controlling the virus without the need for long term antiretroviral treatment. RV254 is funded by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.