The cancer immunology approach is essentially one which is very similar to the ‘Shock and Kill’ strategy for HIV treatment. To achieve HIV remission, we need a low disease burden. Low levels of inflammation are key for the immune system to work efficiently, and critically, we need sustained host responses that are primed, reside in tissues, and target susceptible epitopes. Oncologists struggle with the same issues and are developing many drugs that can help achieve the desired outcomes for HIV research.
Over 100 immunotherapeutic studies have been performed in people, with most involving therapeutic vaccines. All have shown essentially negative results in terms of the HIV reservoir. Ultimately, we need better vaccines and combinations, and there is excitement with cancer vaccine research into RNA vaccines which are now being repurposed for HIV cure. Studies of toll-like receptor (TLR) agonists as vaccine adjuvants demonstrate potential as a functional cure for HIV.
Oncologists are now aggressively targeting immunosuppressive pathways. PD-1 blockade studies in PLWH are not possible due to the safety profile, so current studies are carried out in patients who have both cancer and HIV. It is suggested that if PD-1 can be blocked directly, we may be able to block an HIV-infected cell directly, thereby possibly destroying the virus.