Combining Prevention Strategies

Today I had a chance to talk to Mario Roederer, a T-cell immunologist at the Vaccine Research Center at the National Institute of Allergy and Infectious Diseases and a co-organizer of the “Protection from HIV” track at the Keystone meeting. He said the goal of the track was “to really expose the vaccine community to the microbicides people and vice versa because these approaches will have to be undertaken together in the future.” Roederer, who is married to microbicide researcher Laurel Lagenaur, said that as microbicides are becoming more specific, they are more similar to vaccines, which is why it is time that vaccinologists and microbicide researchers interact. 

In one of the final talks of the meeting, Robin Shattock of St. Georges, University of London, another co-organizer of the "Protection from HIV" track of the meeting, also said that different prevention technologies such as vaccines, oral PrEP, topical PrEP in the form of microbicides containing ARVs, and circumcision, should be deliberately combined. He said that one such strategy, combining vaccination and PrEP, could result in “protected exposure.” This means that a vaccinated person also receiving PrEP won’t get infected even if they get exposed to a virus that’s not an ideal match for the vaccine. At the same time, their immune system will still repeatedly get exposed to the virus for a short time. Such repeated protected exposures might help broaden the immune response of the vaccine, said Shattock, who is currently testing the approach in nonhuman primates.