Context
Encouraged by the trials, researchers say the registered vaccine will reached the market in two years
What has happened?
A malaria vaccine that mimics a mosquito bite yielded encouraging results in human trials, raising hopes for thwarting a parasite that kills a child every two minutes.
Name of the drug
The candidate drug, called PfSPZ, provided up to 100% protection for 10 weeks in a trial in Germany, although a trial in real life conditions in Mali gave a lower level of defence, they reported in two separate studies
- PfSPZ is being developed against the Plasmodium falciparum mosquito-borne parasite, by far the deadliest type. Further trials are to follow in Mali, Ghana, the U.S. and Gabon.
Working
PfSPZ uses a live, immature form of the malaria parasite, called a sporozoite, to stimulate an immune reaction in humans. Two types of vaccine is there,
- One, in which sporozites are radiated before being injected (Irradiated sporozites). In this case a high dosage of live malaria parasites i.e. sporozites was administered to volunteers. The highest dose conferred up to 100% immunity
- Second is the one in which Sporozites are not exposed to radiation. These are injected along with Chloroquine. In this case a low dosage was administered to volunteers
Observations
All the volunteers in the high-dose group enjoyed malaria protection 10 weeks after the last dose, compared to six out of nine in the medium and three out of nine in the low-dose groups
Another vaccine
Another vaccine called RTS,S, developed by GlaxoSmithKline, is being tested in children — the most affected population.It is considered the most advanced candidate, but results last year from a Kenyan trial showed it was only about four per cent effective after seven years
