Chikungunya Vaccine Trial Shows Promising Result

New Delhi: A potential chikungunya vaccine has shown promising results in a large new trial, AFP reported.

French-Austrian drugmaker Valneva’s vaccine candidate to fight the mosquito-borne virus, which has caused occasional outbreaks across the world, was carried out in the United States, a study said on Tuesday.

There is no vaccine or treatment currently available for chikungunya, which leads to fever and at times debilitating joint pain, though it is rarely fatal.

According to Valneva, its vaccine candidate VLA1553 is the first to be reviewed by health authorities after application for approval in the US and Canada.

The recently-conducted randomised, placebo-controlled phase 3 trial aimed to find out how often the live-attenuated vaccine, which uses a weakened form of the virus, produced an immune response.

Out of a sub-group of 266 people who received the vaccine, 263 (that is, 99%) developed antibodies that could neutralise chikungunya virus, according to the study published in The Lancet journal.

In a broader trial of 4,100 healthy adults, the single-shot vaccine was deemed ‘generally safe’, with side-effects similar to other vaccines.

The study revealed that just 2 persons developed serious side-effects linked to the vaccine, but both recovered fully.

Martina Schneider, Valneva’s clinical strategy manager and lead author of the study, called the results ‘promising’.

“This could be the first chikungunya vaccine available for people living in endemic regions, as well as for travellers to endemic areas or areas at risk for an upcoming outbreak,” she said in a statement.

Several public health experts have expressed concern that chikungunya could be a potential pandemic threat in near future as climate change pushes mosquitoes into new regions.

Hence the new study was good news for “chikungunya virus pandemic preparedness,” felt Kathryn Stephenson, an infectious disease specialist at Beth Israel Deaconess Medical Center in the US.

However, the vaccine could be less effective in areas with a built-up immunity to chikungunya, she added.

Some experts exercised caution about the positive results as the trial was carried out on people in the US, where the virus is extremely rare. They are of the view that more research is needed.

Chikungunya, first identified in Tanzania in 1952, has so far been recorded in around 110 countries, according to the World Health Organization – mainly in Africa and Asia, and some in the Americas.

Another chikungunya vaccine candidate, developed by Denmark’s Bavarian Nordic, is also undergoing phase 3 trials.