Plants with antimalarial properties: A systematic review of the current clinical evidence

Abstract

Abstract Introduction Malaria is one of the most common major health problems in tropical low-and middle-income countries, with antimalarial drugs being highly effective but also threatened by increasing drug resistance. Clinically efficacious, well-tolerated antimalarial plants could be an important alternative treatment. This systematic review aims at identifying and critically appraising clinical trials testing plants with antimalarial properties for malaria treatment and/or prophylaxis. Methods Studies were identified through PubMed, Elsevier Scopus and Cochrane Central, and scanning article reference lists. Records were published in English between 01/01/2005 and 15/01/2018. A framework for analysis based on the CONSORT statement was used for data extraction. Risk of bias was assessed. A meta-analysis could not be conducted due to data heterogeneity. Results Nine studies met inclusion criteria. Extracts from Argemone mexicana, Artemisia annua, Citrus aurantifolia, Nauclea pobeguinii, Nycthanthes arbor-tristis and Vernonia amygdalina were examined. Methodological rigorosity varied. Adequate clinical response on day 14 with A. mexicana was 81% (p\u2009=\u20090.027) in one study and 89% (95% CI 84.1–93.2) on day 28 in another study. Similarly, 87.9% of participants taking N. pobeguinii had an adequate clinical response on day 14 (p\u2009=\u20090.003). The risk of bias and study quality varied. Two studies had a Jadad score of 3 and all others but one had a score of 1. All herbal preparations were safe with no moderate or severe adverse events being reported. Conclusions Studies have demonstrated that antimalarial plants show promise for malaria treatment and prophylaxis. A. mexicana and N. pobeguinii extracts were supported by the best evidence. More work should be undertaken to better understand relevant approaches.