Glaxo pulls out anti malaria drugs
pharmaceutical giant GlaxoSmithKline is recalling its malaria drug Lapdap and has discontinued development of another malaria drug, Dacart, saying the drugs can lead to anaemia in some patients. Experts say the move is a setback to fight the disease.
On February 29, Glaxo said its clinical trials had found that both the drugs, Lapdap and Dacart, could cause a drastic lowering of haemoglobin levels in patients who had a certain hereditary enzyme deficiency, called Glucose-6-phosphate dehydrogenase deficiency. It affects normal functioning of red blood cells, lowering haemoglobin level, and causes anaemia. It is common among 10-25 per cent of the population in the malaria-endemic sub-Saharan Africa. In India also, the deficiency is found in 27 per cent of the total population.
Though Glaxo has sold Lapdap only in Kenya, this is the first time that an anti-malaria drug has been recalled from the market. The decision to halt development of an anti-malaria drug (Dacart) at a late stage, however, is not a first-time event. A year ago, Ranbaxy was asked to drop its anti-malaria drug, oz277, during clinical trials. Both the researches were funded by the Medicines for Malaria Venture (mmv), a Geneva-based ngo. "Funding for these drugs was stopped because they did not meet our norms of efficacy, safety and low-cost,' says Anna Wang of mmv.
The move is critical at a time when the malaria parasite is getting increasingly resistant to existing drugs. Earlier, Plasmodium vivax was widespread but as quinine drugs made inroads, Plasmodium falciparum has become more dominant.
"Research is a long-term process. We can't wait for resistance to develop and then look for drugs,' says Bhawna Sharma of the Drugs for Neglected Diseases Initiative-India. Currently, artemisinin-based drugs are effective against P falciparum. But they are too expensive. Public health officials want many drugs to promote price competition and give patients more choices.