Public Release: 

New malaria vaccine shows promise in early clinical trial

PLOS

A malaria vaccine remains the most desired tool to combat the worsening malaria epidemic in many developing countries. Pierre Druilhe and colleagues (from the Institut Pasteur in Paris) have completed the first human trial of a vaccine based on MSP3, a protein present on the surface of the malaria parasite, with very encouraging results.

As the researchers report in the international open-access medical journal PLoS Medicine, most of the 30 healthy volunteers who received the vaccine developed strong, specific, and in some cases long-lasting immune responses against the MSP3 protein.

However, as researchers have learned from many early HIV and malaria vaccine trials, the crucial question is whether these immune responses mean that vaccinated people are actually protected against malaria. The straightforward way to test this is to expose the vaccinated trial participants to malaria and see if they are protected. However, this risky test is not ethical during the early stages of vaccine testing.

But Druilhe and colleagues were nevertheless able to take their early trial a step further: They demonstrated that antibodies from the blood of vaccinated volunteers were able to inhibit growth of the malaria parasite in two independent laboratory assays.

"A particular strength of the MSP3 trial is that functional assays [tests to see whether the vaccine could kill parasites] were utilized to assess the quality of the antibody response produced," say Brendan Crabb and James Beeson in an accompanying Perspective. However, they also point out that important questions remain, some of which will only be answered in additional clinical trials. Based on the results described in the PLoS Medicine article, Druilhe and colleagues have started a Phase II efficacy field trial of the MSP3 vaccine in malaria-exposed individuals.

###

Citation: Druilhe P, Spertini F, Soesoe D, Corradin G, Mejia P, et al. (2005) A malaria vaccine that elicits in humans antibodies able to kill Plasmodium falciparum. PLoS Med 2(11): e344.

Related PLoS Medicine Perspective:
Citation: Crabb BS, Beeson JG (2005) Promising functional readouts of immunity in a blood-stage malaria vaccine trial. PLoS Med 2(11): e380.

PLEASE ADD THE LINK TO THE PUBLISHED ARTICLE IN ONLINE VERSIONS OF YOUR REPORT: http://dx.doi.org/10.1371/journal.pmed.0020380

PRESS-ONLY PREVIEW OF THE ARTICLE: http://www.plos.org/press/plme-02-11-crabb.pdf

CONTACT: Pierre Druilhe
Institut Pasteur
Bio-Medical Parasitology Unit
28, rue du Dr Roux
Paris, France 75015
+33-(1)-45-68-85-78
+33-(1)-45-68-86-40 (fax)
druilhe@pasteur.fr

PLEASE MENTION THE OPEN-ACCESS JOURNAL PLoS MEDICINE (www.plosmedicine.org) AS THE SOURCE FOR THIS ARTICLE AND PROVIDE A LINK TO THE FREELY-AVAILABLE TEXT. THANK YOU.

All works published in PLoS Medicine are open access. Everything is immediately available without cost to anyone, anywhere--to read, download, redistribute, include in databases, and otherwise use--subject only to the condition that the original authorship is properly attributed. Copyright is retained by the authors. The Public Library of Science uses the Creative Commons Attribution License.

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.