In 2015, 17 million HIV-infected individuals worldwide were on antiretroviral drug therapies, which are remarkably effective in suppressing the virus. Yet, 6000 people a day became newly infected, making the quest for an effective and safe HIV vaccine a major global priority. However, developing a vaccine has been difficult for reasons related to the nature of the virus and its life cycle, including early integration into the host genome and the highly glycosylated, compact, and sequence-variable nature of the envelope (Env) “spike” that is the sole target of neutralizing antibodies (and typically associated with vaccine protection). Where are we, then, on the path to a vaccine?
