Present data on novel antimalaria drugs: Artemisinin (Qinghaosu) derivatives

Artemisinin or Qinghaosu (QHS) and its derivatives (mainly artemether and a rtesunate) are novel and the most rapidly actin antimalarial drugs, effecti ve in adults and children against all the Plasmodium of humans, including m ulti-drug resistant Plasmodium falciparum. Resistance to these drugs has no t been identified so far. QHS derivatives are very well tolerated and there is no evidence of serous clinical toxicity in man. The neurotoxicity seen in animals after high doses of certain compounds has not been reported in h umans. In the treatment of severe malaria, QHS administered by either the i ntramuscular (artemether and artesunate) or intravenous (artesunate) route, are at least as effective as quinine, and are simpler to use. Intramuscula r artemether appears to be an excellent alternative to intraveinous quinine , which is specially important since quinine resistance is common in Asia a nd a decrease of sensitivity to quinine has been reported in Africa. For th e treatment of uncomplicated malaria, the use of QHS must be highly selecti ve. Treatment by QHS is only totally justifiable in areas where multi-drug resistant strains are prevalent and always concurrently with an other effec tive, longer-acting, antimalarial drug (mefloquine, preferably). This combi nation approach is associated with an accelerated antimalarial response. It avoids or limits the risk of recrudescences, and protects both drugs from the development of resistance. Artemether and artesunate have also been adm inistered by the rectal route with highly promising results for treatment o f severe malaria. This rout eliminates several disadvantages or risks assoc iated with injections. The best indication for rectal administration willl be probably a rescue treatment of severe malaria in rural and poorly equipp ed dispensaries before transfer to hospital for treatment using conventiona l modalities. All QHS derivatives should not be used for chemophophylaxis.