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Updated: Aug 22, 2026

Toxicological Assays for Testing Effects of an Epigenetic Drug on Development, Fecundity and Survivorship of Malaria Mosquitoes
Published on: January 16, 2015
The difference between effectiveness and efficacy of antimalarial drugs in Kenya
Abdinasir A Amin1, Dyfrig A Hughes, Vicki Marsh
1Kenya Medical Research Institute/Wellcome Trust Collaborative Programme, Nairobi, Kenya. aamin@wtnairobi.mim-com.net
Objective:
To demonstrate the difference between effectiveness and efficacy of antimalarial (AM) drugs in Kenya.
Methods:
We undertook a series of linked surveys in four districts of Kenya between 2001 and 2002 on (i) community usage of nationally recommended first- and second-line AM drugs; (ii) commonly stocked AM products in the retail and wholesale sectors; and (iii) quality of the most commonly available first- and second-line AM products. These were combined with estimates of adherence and clinical efficacy to derive overall drug effectiveness.
Results:
The overall modelled effectiveness for sulphadoxine-pyrimethamine (SP) was estimated to be 62% compared with 85% for reported SP clinical efficacy. For amodiaquine the modelled effectiveness was 48% compared with 99% reported efficacy during the same time period.
Conclusions:
The quality of AM products and patient adherence to dosage regimens are important determinants of drug effectiveness, and should be measured alongside clinical efficacy. Post-registration measures to regulate drug quality and improve patient adherence would contribute significantly to AM drug performance.
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