Latest:
 

Breakthrough malaria vaccine tantalizingly close

By David Lindsay
Nyanza Province, Kenya
June 10, 2011

Two year old Philip Ouma buries his head in his mother’s chest as a plunger with an inch-long needle glides into his arm and deposits its contents.

Unlike many of the 15,000+ babies and toddlers in this vaccine trial, Philip doesn’t burst into tears or even make a sound. But if this vaccine works, there will be cries of relief far beyond this remote part of western Kenya.

Scientists have been trying for decades to develop a vaccine to combat malaria, a disease that stalks African children, who account for the vast majority of the 800,000 people who die of the condition each year.

But now, a vaccine could finally be near. RTS,S, also known as Mosquirix, has been 30 years in the making. Developed by GlaxoSmithKline and the PATH Malaria Vaccine Initiative, it’s in the midst of a phase three trial in seven African countries. No malaria vaccine candidate has ever come this far.



In it’s smaller phase two trials, RTS,S reduced severe malaria cases by around 50%. Not a silver bullet, but it could save hundreds of thousands of lives.

Here in western Kenya, the government has joined with the U.S.-based Centers for Disease Control and Prevention (CDC) and the Walter Reed Army Institute of Research to help run several trial sites.

Dr. Louis Macareo, who directs Walter Reed’s clinical trial center in Kombewa, says this vaccine is different because instead of attacking the virus, it seeks to boost the immune system. “When you get malaria it spawns off a cascade of events in your body where your body produces antibodies that fight against the malaria,” explains Macareo. “What we try to duplicate with the vaccine is to stimulate the body’s immune system to produce similar antibodies.”

The vaccine has been developed specifically for babies and toddlers, whose immune systems are still developing, making them the easiest prey. If approved for widespread use, RTS,S would be given in tandem with other childhood vaccines, enabling overstretched health systems to introduce it with little difficulty.

And it’s hoped that implementation could be just around the corner. Trial results from one group of children will be released later this year, with the rest coming in 2012. If it meets expectations, RTS,S could be approved for distribution by 2015.

Kayla Laserson, the Director of a CDC partnership with Kenya’s main research institute, known as KEMRI, says implementation talks are already underway. “Certainly the preparations for it are there to go straight from discovery that this is in fact efficacious to policy, to implementation, all those conversations are happening so everyone is ready.”

But what if the results of the phase three trial are disappointing? What if approval is not forthcoming? “If not,” says Laserson, “then all the preparation is there for the next time.”

David Lindsay is the Managing Editor of Global Health Frontline News
www.ghfn.org

NOTE: Follow vaccine news from the June 13th meeting of GAVI – The Global Alliance for Vaccines and Immunisation.

Share this story