Authors: Martha Powell, Future Science Group
The National Institute of Allergy and Infectious Diseases (MD, USA) has launched a Phase I clinical trial to test a novel vaccine that hopes to to provide broad protection against multiple mosquito-borne diseases including Zika, malaria and dengue.
The vaccine, termed AGS-v, was developed by a pharmaceutical company SEEK (London, UK) and contains four synthetic proteins from the mosquito salivary glands. The vaccine takes a novel approach, it aims to generate an immune response to mosquito saliva, as opposed to a specific pathogen, and the team hope this strategy will protect against multiple diseases.
National Institute of Allergy and Infectious Diseases Director Anthony S. Fauci commented: “Mosquitoes cause more human disease and death than any other animal. A single vaccine capable of protecting against the scourge of mosquito-borne diseases is a novel concept that, if proven successful, would be a monumental public health advance.”
This study will assess the experimental safety of the vaccine and its ability to stimulate an immune response. The double-blind trial is expected to enrol 60 healthy individuals aged 18–50 who will be assigned to one of three vaccine regimens: receiving two vaccine doses, receiving two vaccine doses, both with an adjuvant, or receiving two placebo injections of sterile water.
The vaccines efficiency will then be assessed as participants will be exposed to Aedes aegypti mosquitoes, which will not be carrying disease. The researchers will then take blood samples at different time points following this exposure and assess if vaccinated participants have a modified response to mosquito bites.
The team will also observe the mosquitoes after they have bitten the participants, as the group suspect that feeding on ASG-v vaccinated individuals could lead to altered behavior and adverse effects in the insects. If this is the case, the vaccine also has the potential to impact disease transmission, perhaps acting as an insect-control measure.
The follow-up from the study is expected to last 10 months, with initial results being completed in summer 2018. This vaccine could present a promising new approach against mosquito-borne diseases with a high burden across the globe, and could target these much more broadly than current strategies.