PrEP as a Pillar in HIV Research

In the research field of human immunodeficiency viruses (HIV), a clear trend towards pre-exposure prophylaxis (PrEP) is emerging, as two fundamental challenges in vaccine development persist: the lack of a decisive vaccination success and the difficulties with suitable animal models. Almost 30 years have passed since former U.S. President Bill Clinton urged the pharmaceutical industry to develop a vaccine against acquired immune deficiency syndrome (AIDS), yet no candidate has made it to market. Major pharmaceutical companies like Merck and Johnson & Johnson have already withdrawn from HIV vaccine development in the past. This development has led to a continuous decline in investments in HIV vaccines, says Dr. Jonathan Weber, a co-director of the research center at the Pears Cumbria School of Medicine in Carlisle, Wales. Nevertheless, he sees glimmers of hope: With the approval of Gilead Sciences' long-acting PrEP therapy Sunlenca (Lenacapavir) and other encouraging successes in the field of antiretroviral therapy, investment in PrEP research remains. Such drugs are administered to high-risk individuals who are not yet infected with HIV to prevent transmission. Sunlenca offers new possibilities as it can be administered intravenously every six months. Dr. Weber, who served as the founding editor of the journal AIDS from 1987 to 1992 and co-founded the WHO network for HIV characterization in 1992, emphasized in an exclusive interview that vaccine development is still empirical science. Without a robust animal model and in view of the lack of natural immunity in humans, it is difficult to develop a successful vaccine. He explained that PrEP is a promising way to prevent transmission, especially in high-risk groups such as homosexual men in metropolitan areas. The introduction of long-acting injectable PrEP therapies, such as Sunlenca, can have a transformative effect by providing an extended, vaccine-like impact in prevention.