LSTM Home > LSTM Research > LSTM Online Archive

Measuring windows of selection for anti-malarial drug treatments.

Kay, Katherine and Hastings, Ian ORCID: (2015) 'Measuring windows of selection for anti-malarial drug treatments.'. Malaria Journal, Vol 14, e292.

Malaria_J_14_292.pdf - Published Version
Available under License Creative Commons Attribution.

Download (1MB) | Preview



The long half-lives of malaria 'partner' drugs are a potent force selecting for drug resistance. Clinical trials can quantify this effect by estimating a window of selection (WoS), defined as the amount of time post-treatment when drug levels are sufficiently high that resistant parasites can re-establish an infection while preventing drug-sensitive parasites from establishing viable infections.


The ability of clinical data to accurately estimate the true WoS was investigated using standard pharmacokinetic-pharmacodynamic models for three widely used malaria drugs: artemether-lumefantrine (AR-LF), artesunate-mefloquine (AS-MQ) and dihydroartemisinin-piperaquine (DHA-PPQ). Estimates of the clinical WoS either (1) ignored all new infections occurring after the 63-day follow-up period, as is currently done in clinical trials, or, (2) recognized that all individuals would eventually be re-infected and arbitrarily assigned them a new infection day.


The results suggest current methods of estimating the clinical WoS underestimate the true WoS by as much as 9 days for AR-LF, 33 days for AS-MQ and 7 days for DHA-PPQ. The new method of estimating clinical WoS (i.e., retaining all individuals in the analysis) was significantly better at estimating the true WoS for AR-LF and AS-MQ.


Previous studies, based on clinically observed WoS, have probably underestimated the 'true' WoS and hence the role of drugs with long half-lives in driving resistance. This has important policy implications: high levels of drug use are inevitable in mass drug administration programmes and intermittent preventative treatment programmes and the analysis herein suggests these policies will be far more potent drivers of resistance than previously thought.

Item Type: Article
Additional Information: The electronic version of this article is the complete one and can be found online at:
Subjects: QV Pharmacology > Anti-Inflammatory Agents. Anti-Infective Agents. Antineoplastic Agents > QV 256 Antimalarials
QV Pharmacology > QV 38 Drug action.
WC Communicable Diseases > Tropical and Parasitic Diseases > WC 750 Malaria
WC Communicable Diseases > Tropical and Parasitic Diseases > WC 765 Prevention and control
Faculty: Department: Biological Sciences > Department of Tropical Disease Biology
Digital Object Identifer (DOI):
Depositing User: Mary Creegan
Date Deposited: 07 Sep 2015 10:27
Last Modified: 19 Sep 2019 11:29


View details

Actions (login required)

Edit Item Edit Item