Researchers with MHRP’s B cell immunology lab are working to screen hundreds of samples from the program’s African Cohort Study (AFRICOS) to identify and isolate the next generation of potent, broadly neutralizing antibodies (bNAbs) that have potential to prevent or treat new and evolving strains of HIV.
Many of the bNAbs currently in clinical development are becoming less potent over time because the HIV virus is mutating and evading those antibodies. Also, most existing bNAbs were identified and isolated from people living with HIV subtypes B and C, meaning products developed from those antibodies might not be as effective against other underrepresented HIV subtypes. Isolating new bNAbs from AFRICOS participants could potentially address these issues.
AFRICOS is a large, long-term cohort study conducted at multiple African sites in Kenya, Nigeria, Tanzania and Uganda that primarily evaluates HIV prevention, care and treatment services. The study also prospectively stores specimens that can be used for virologic and immunology research.
AFRICOS is continually enrolling new participants living with HIV, so any bNAbs that might be identified and isolated from these samples may be more effective against currently circulating strains than bNAbs in current prevention and treatment trials. AFRICOS takes place in regions where underrepresented HIV subtypes are prevalent, which could lead to the development of a more diverse slate of candidate bNAb products. Identifying and developing multiple potential bNAb candidates is also beneficial because administering cocktails of multiple antibodies that target different regions of the HIV virus provides greater breadth.
MHRP’s B cell immunology team, led by Dr. Shelly Krebs, screened more than 500 AFRICOS samples to identify those with antibodies that can neutralize a panel of different HIV strains. The next steps will be to isolate and characterize monoclonal antibodies to advance the most promising neutralizers. Agreements are in place to collaborate with VIR Biotechnology and the NIH Vaccine Research Center to help isolate monoclonal antibodies.