used to explore the advantages and challenges of creating enterprises that do not currently exist in a country. In this case, however, even though A. annua is not yet commercially grown in Nigeria and ACTs are not widely produced and marketed there, companies are actively striving to do so, including some that participated in the meeting. Moreover, the future market for ACTs in Nigeria may be heavily influenced by external factors, such as broad subsidies by bilateral and other donor agencies or the production of a synthetic equivalent of the active ingredient. Without a major global subsidy, the ACTs market is likely to grow slowly and uncertainly, whereas with a subsidy the market could be transformed. Unfortunately, whether current planning will result in such a subsidy cannot yet be predicted. This uncertainty is, in fact, part of the landscape that must be negotiated in the real world.

THE USE OF ARTEMISININ DERIVATIVES

Artemisinin, the active ingredient extracted from the leaves of the Artemisia annua plant, has been used for centuries in Chinese traditional medicine to treat fever. Chemical derivatives of artemisinin, in combination with other antimalarial drugs, constitute the artemisinin-based combination therapy, or ACT, which is the most effective treatment for falciparum malaria, the most dangerous form of the disease caused by the Plasmodium falciparum parasite.

Malaria kills more than a million people a year, mainly children. Since the seventeenth century, malaria has been treatable, but, historically, there has never been an adequate supply of effective drugs for more than a small percentage of the sufferers. In the 1960s, chloroquine, a synthetic drug, became available at low prices in tropical countries and was effective for decades. Eventually, however, parasite resistance to chloroquine evolved in Asia, and it has now spread throughout Asia and Africa. Chloroquine can be purchased for about $.10 per course of treatment in many places in Africa, but today it is nearly useless against falciparum malaria, because resistant forms of the parasite are now widespread.

In 2001 the World Health Organization (WHO) declared that artemisinin derivatives should replace chloroquine as the first-line treatment for uncomplicated malaria; these drugs have since proven to be best for severe malaria as well. There is as yet no known resistance of Plasmodium falciparum to artemisinin-based drugs. In the preferred ACT formulation, derivatives of the artemisinin compound extracted from the plant are coformulated with another antimalarial drug. The main reason for combining drugs is to inhibit the development of resistance to either drug, much like the approach taken today for HIV/AIDS. Thus, if the parasite begins to develop resistance to artemisinin, the other drug will still kill



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