Phase 2 clinical trial of chikungunya vaccine opens to volunteers
“The recent re-emergence of chikungunya virus in this hemisphere has rapidly become a significant health burden,” NIAID Director Anthony Fauci said. “Our chikungunya vaccine development efforts are part of a broader research effort to prevent, diagnose, treat and ultimately control this painful illness, which can strike anyone unlucky enough to be bitten by an infected mosquito.”
With the positive results of the Phase 1 trial, using the vaccine developed by NIAID scientists, the NIH sponsored the Phase 2 trial. The new trial will enroll 400 healthy adult volunteers ages 18 to 60 in the Caribbean. Half will receive the vaccine and the remaining volunteers will receive a placebo. Blood samples will be drawn at regular intervals to determine each volunteer's immune response.
The experimental vaccine does not use inactivated or weakened whole virus. Instead, the vaccine uses virus-like particles (VLPs), which stimulate the immune response in the body. The actual virus is not needed, so high-level biocontainment facilities are not required to produce the chikungunya vaccine.
The chikungunya virus is spread by mosquitoes. After being bitten and infected, victims suffer from severe joint pain, fever and headache which generally fade after a week but may last for months or years. It first appeared in the Caribbean in 2013 and spread rapidly, with more than 621,000 cases reported in 2015.