The Averting Readmissions for Malaria and Outpatient Reinfections (ARMOR) Trial

Malaria due to Plasmodium falciparum is a public health priority in sub-Saharan Africa and other endemic areas, yet clinical interventions for severe malaria remain understudied. Children who survive a hospitalized episode of severe malaria remain at increased risk of morbidity and mortality for as long as 18 months post- discharge, mainly due to recurrent malaria. Thus, children who are convalescent from severe malaria represent a high-risk population who stand to benefit from interventions that prevent recurrent malaria. A small number of prior studies have tested intermittent preventive treatment-based approaches with equivocal results. The proposal sets to test the effectiveness of a novel approach using secondary chemoprophylaxis with the causally- active antimalarial (i.e., against the liver-stage of the parasite), atovaquone-proguanil (AP), and reactive focal vector control with indoor residual spraying (rf-IRS) both alone and in combination. The trial site in Nchelenge District, Zambia is a high burden area with sustained transmission throughout the year and where severe malaria accounts for up to one-third of pediatric hospital admissions at any given time. This study will leverage substantial infrastructure from the NIH- funded International Centers of Excellence for Malaria Research. The central hypothesis is that the risk of P. falciparum reinfection following an episode of severe malaria can be averted by the combination of causal prophylaxis using AP and vector control using rf-IRS. We expect that AP prophylaxis and rf-IRS will reduce morbidity and mortality in children convalescent from severe falciparum malaria. The innovation of the study includes in its use of AP for secondary chemoprophylaxis—uniquely notable for its hepatic as well as blood schizonticidal activity, in contrast to other available agents which are limited to blood-stage parasites—and a novel application of focal vector control in an understudied, high-risk population. The proposed trial is significant because it will furnish evidence to inform the case management of severe malaria which has seen little advancement in the preceding decades. It will test the effectiveness of secondary chemoprophylaxis and rf-IRS, alone and in combination, among a high-risk patient population with the potential to prevent an estimated 2.8 million rehospitalizations and over 100,000 deaths annually.

Project details

Combination of Interventions
Drug-based Strategies
Vulnerable Populations

Jul 2022 — Jun 2023

$245,625

Zambia