Net Effect - Pharmaceutical Executive


Net Effect

Pharmaceutical Executive

Coartem Comes of Age

Ripley Ballou has chased the malaria vaccine RTS,S for 25 years. Although far from a silver bullet, its 35 to 49 percent efficacy is the best available.
To many observers, the turning point came in January 2004 in the form of a Lancet article. Amir Attaran, a public health advocate and law professor at the University of Ottawa, accused WHO and the Global Fund to Fight AIDS, Tuberculosis, and Malaria of medical malpractice. Their crime: funding African public health initiatives that used chloroquine and sulfadoxine-pyrimethamine (SP)—inexpensive antimalarials that had largely lost their efficacy to drug resistance. Instead, Attaran argued, these organizations should fund only drugs that employed artemisinin, an extract of the Chinese sweet wormwood tree. (These drugs are known collectively as artemisinin-based combination drugs, or ACTs.) Attaran's paper was a call to action after nearly 50 years of increasingly ineffective, underfunded, and fatiguing efforts to combat the epidemic.

Certainly the fight against malaria didn't start out depressed. In 1955, just four years after malaria was eliminated from the United States, WHO, armed with choloroquine and DDT, started its Malaria Eradication Program to abolish the disease worldwide. But by 1969, WHO conceded failure—changing its name to the Division of Malaria and Other Parasitic Diseases—and downgraded its malaria mission from "eradication" to "control."

In Africa, the HIV and malaria epidemics overlap. More research is needed to better understand how to treat co-infected patients. and necessitate a new approach to patient care and research.
Chloroquine was a great medicine—cheap to make and safe to use—but easy for the mosquito-borne parasites that cause malaria to neutralize via resistance. By the early '90s, it failed in as many as 80 percent of patients, and today it is virtually useless. SP, an inexpensive alternative to chloroquine, was introduced in 1967, and resistance was found later that year. A recent University of Maryland study reported that, in Malawi, SP has only a 21 percent cure rate.

By the mid-'70s, at about the same time Europe was declared free of malaria, WHO once again decreased its malaria-control measures, citing financial constraints. The cutback continued through the '80s, and the incidence of malaria skyrocketed in countries where it was endemic. The '90s brought some renewed attention, including the Roll Back Malaria Partnership, supported by WHO, UNICEF, the United Nations Development Programme, and the World Bank. But by then HIV was producing a new, more vulnerable category of patient, and the partnership had little actual impact on malaria-related deaths.

But then came Attaran's paper, which struck a nerve. "The policy change resulting from that article was one of the most rapid we've ever seen," says Melanie Renshaw, a malaria advisor for UNICEF. The Global Fund moved fast to recommend the use of ACTs as first-line therapy, and today 68 countries have adopted them in their malaria-control guidelines.

Many Possibilities, Few Certainties
As the only WHO-prequalified ACT, Novartis' Coartem (artemether-lumefantrine) is the preferred product of public programs. Artemisinin has been used for centuries in folk remedies for fever. But researchers discovered that when they combined artemisinin derivatives (such as artemisinin and artsenuate) with lumefantrine and related compounds, the resulting drug not only killed malaria parasites within 48 hours but also worked against multidrug-resistant strains. However, Novartis wasn't prepared for the impact of the new guidelines. Public health officials remember 2005 as a year of massive ACT shortage—just as countries began to request the drugs.


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