Drug Combinations of Atovaquone-Proguanil (AP) With ACT

Overview

Investigators are conducting this study due to recent reports of many of existing malaria drugs becoming less effective for treatment of malaria. The drugs may not always kill all the parasites, therefore not all patients with malaria are being cured. The main objective of the study is to find out which malaria drugs and what drug combinations are still effective in Cambodia, an area of multi-drug resistance where 4-5 artemisinin-based combination therapies have shown inadequate response, below that established by the World Health Organization (WHO). New drug combinations (taking more than one drug for malaria at the same time), as long as well tolerated, can provide cure in patients that harbor parasites not responsive to standard first-line medications. Human genetic testing will be done to identify patients who may have suboptimal response to treatments and to study the differences in human gene expression to explain why some persons are at higher risk of complications during treatment. Markers of drug resistance to commonly used antimalarial drugs will also be evaluated and shared with national malaria program (CNM) to better guide future malaria treatment decisions in Cambodia.

Efficacy to drugs that are currently available and new antimalarial candidates that are in development are threatened by multidrug resistant (MDR) malaria parasites, widely prevalent in Cambodia. Without effective interventions, MDR malaria can pose a substantial public health threat in the years to come. Therefore, accurate, timely and relevant data on antimalarial drug resistance is of critical importance. Prompt, effective and well-tolerated treatment remains one of the cornerstones in the malaria case management. Recent malaria outbreak in Thailand and rise of malaria cases observed in Cambodia in 2017 has brought to the forefront the urgency with which new drug candidates and new combination drug treatments must be identified; otherwise, patients may be left with ineffective treatments. Lack of available alternatives has a potential to result in significant setback to the recent gains in malaria control and malaria elimination efforts. Innovative approaches to treatment proposed here, using current ACTs in combination with non-ACT drugs, such as atovaquone-proguanil, need to be investigated to assess drug tolerability and overall efficacy when used under combination treatment. By early investment in the studies of drugs such as pyronaridine-artesunate (ASPY), in combination with other antimalarials, and drug combinations proposed under this protocol, this study will try to provide the latest evidence on the interventions that are most likely to work, even in areas of MDR, such as Cambodia, and along the Cambodia-Thai border. It is hoped that our approach for using combination treatments will not only provide more effective treatments, but it might prolong the lifespan of the remaining antimalarials and delay the spread of MDR malaria to neighboring countries.