Evidence basis for antimalarial policy change in Sierra Leone: five in vivo efficacy studies of chloroquine, sulphadoxine–pyrimethamine and amodiaquine
To provide nationally relevant information on the antimalarial efficacy of chloroquine (CQ), sulphadoxine–pyrimethamine (SP) and amodiaquine (AQ) in Sierra Leone, with a view to updating antimalarial policy in the country. Methods
Between October 2002 and May 2003, standard WHO methodology for in vivo efficacy assessment was used in five sites to study the therapeutic response of 6–59 months old uncomplicated Plasmodium falciparum malaria cases treated with CQ (n = 247), SP (n = 353) or AQ (n = 434). Follow-up was of 28 days, with polymerase chain reaction genotyping to distinguish late recrudescences from re-infections. Results
Overall 85.3% of patients reached an analysable endpoint. CQ failure proportions were very high, ranging from 39.5% (95% CI: 25.0–55.6) in Kabala to 78.8% (65.3–88.9) in Kailahun. Early failures under CQ were frequent. SP efficacy was also disappointing, with failure from 23.2% (13.9–34.9) in Kabala to 46.1% (35.4–57.0) in Kailahun. AQ resistance was more moderate, ranging from 5.4% (1.8–12.1) in Makeni to 29.8% (20.3–40.8) in Kailahun, with almost no early failures. AQ also provided more rapid fever and parasite clearance. Conclusion
In a consensus meeting organized by the Ministry of Health and Sanitation, and based on these findings, artesunate (AS) + AQ and artemether–lumefantrine (Coartem™) were identified as the only options to rapidly replace CQ. The choice fell on AS + AQ because of expected high efficacy, lower cost in a blister presentation, and the absence of safety data on artemether–lumefantrine in pregnancy. Donor support is required to support this policy change. Throughout Africa, as SP resistance increases, these two regimens are probably the only options available while newer combinations are developed. Efficacy studies should focus on testing AQ and AS + AQ.
Document Type: Research Article
Affiliations: 1: Epicentre, Paris, France 2: Ministry of Health and Sanitation, Freetown, Sierra Leone 3: World Health Organization, Freetown, Sierra Leone 4: Médecins Sans Frontières Belgium, Brussels, Belgium 5: Médecins Sans Frontières Holland, Amsterdam, the Netherlands 6: Médecins Sans Frontières France, Paris, France 7: Concern Worldwide, Freetown, Sierra Leone 8: World Health Organization Regional Office for Africa, Harare, Zimbabwe 9: Laboratoire de Parasitologie-Mycologie, Bichat Hospital, Paris, France 10: Division of Infection and Immunity, Institute of Biomedical and Life Sciences, University of Glasgow, UK 11: Malaria Working Group, Médecins Sans Frontières, Brussels, Belgium
Publication date: 2005-02-01