Almost half of all artemisinin manufacturers and malaria-endemic countries are “failing to comply” with WHO requirements to sell the treatment in combination with other drugs, which is increasing the risk that malaria parasites will develop resistance to artemsinin, Nature reports. “Of the 69 manufacturers of artemisinin monotherapies that the WHO has identified, 21 have withdrawn monotherapies, and 14 say they intend to comply with the WHO’s recommendations. But the remaining 34 have not yet disclosed their intentions,” Nature writes.

Andrea Bosman, an official at the WHO’s Global Malaria Program, said, many manufacturers have not replied to multiple WHO requests for information. In addition, regulatory authorities in 39 of the 76 countries using malaria drugs have either complied or said they intend to comply with the WHO’s recommendations.

“Artemisinin and its derivatives are the leading treatments for the disease” and are the only malaria drugs “that have not yet seen widespread resistance in malaria parasites,” writes Nature. The WHO will soon publish a briefing about the full scope of the problem and will call for “governments to empower national drug-regulatory authorities to clamp down on offending companies,” according to Nature.

In January 2006, the WHO recommended that artemisinin be given in combination with other drugs for at least three days to reduce the chances of resistance. Now the need to move away from monotherapies has become “all the more urgent” with recent reports of resistance arising in Cambodia, Nature reports (Butler, 7/14).