Comparative Efficacy and Safety of the Artemisinin Derivatives Compared to Quinine for Treating Severe Malaria in Children and Adults: A Systematic Update of Literature and Network Meta-Analysis

Abstract

Background: The artemisinin derivatives are the preferred antimalaria drugs for treating severe Plasmodium falciparum malaria. However, their clinical effectiveness among each other is unknown. Methods: Review protocol was registered with PROSPERO, CRD42020218190. We updated the search strategies of three Cochrane systematic reviews which included published and unpublished randomised control trials (RCTs) that have compared specific artemisinin derivatives to quinine in treating severe malaria. Search included CENTRAL, MEDLINE, Embase, LILACS, ISI Web of Science and trial registries up to February 2021. We screened studies, extracted data, assessed risk of bias, and quality of evidence in duplicate. Separate analyses in the frequentist framework, using a random effects model, with quinine as reference, were conducted for adults and children, and rankings were produced using p-scores to assess mortality, parasite clearance, coma recovery, fever clearance, neurological sequela and adverse events. Findings: Searches identified 818 citations, 33 RCTs were eligible. We pooled 7795 children and 3182 adults. The networks involved artesunate, artemether, rectal artemisinin, arteether and quinine. Compared to quinine, artesunate reduced mortality in children (risk ratio (RR), 0.76; 95%CI [0.65 to 0.89], moderate quality), adults (RR, 0.55; 95%CI [0.40 to 0.75], low quality), and in cerebral malaria (RR, 0.72; 95%CI [0.55 to 0.94], moderate quality).Compared to rectal artemisinin and intramuscular arteether, the efficacy and safety of parenteral artesunate, and intramuscular artemether in treating severe malaria are not clear. Rankings showed that none of the artemisinin drugs were consistently superior in all the outcomes assessed. Indirect evidence produced were of very low ratings due to suspected publication bias and imprecision. Interpretations: Artesunate reduces mortality compared to quinine for both adults and children in Asia, and Africa including cerebral malaria. The artemisinin derivatives remain the best treatment for severe malaria but their comparative clinical effectiveness is yet to be fully explored. Funding Information: Initial part of this review was done as part of Nicholas Nyaaba's MSc from the University of Oxford which was supported by the the Ghana Education Trust Fund (GETFund). Registration Details: PROSPERO, CRD42020218190. Funding Information: Initial part of this review was done as part of Nicholas Nyaaba’s MSc from the University of Oxford which was supported by the Ghana Education Trust Fund (GETFund). Declaration of Interests: The authors have no conflicts of interest to declare.