The World Health Organization (WHO) recommends Artemisinin-based Combination Therapy (ACT) for treating uncomplicated Plasmodium falciparum malaria. This review aims to assist the decision-making of malaria control programmes by providing an overview of the relative effects of dihydroartemisinin-piperaquine (DHA-P) versus other recommended ACTs.
To evaluate the effectiveness and safety of DHA-P compared to other ACTs for treating uncomplicated P. falciparum malaria in adults and children.
We searched the Cochrane Infectious Diseases Group Specialized Register; the Cochrane Central Register of Controlled Trials (CENTRAL) published in The Cochrane Library; MEDLINE; EMBASE; LILACS, and the metaRegister of Controlled Trials (mRCT) up to July 2013.
Randomized controlled trials comparing a three-day course of DHA-P to a three-day course of an alternative WHO recommended ACT in uncomplicated P. falciparum malaria.
Data collection and analysis
Two authors independently assessed trials for eligibility and risk of bias, and extracted data. We analysed primary outcomes in line with the WHO 'Protocol for assessing and monitoring antimalarial drug efficacy’ and compared drugs using risk ratios (RR) and 95% confidence intervals (CI). Secondary outcomes were effects on gametocytes, haemoglobin, and adverse events. We assessed the quality of evidence using the GRADE approach.
We included 27 trials, enrolling 16,382 adults and children, and conducted between 2002 and 2010. Most trials excluded infants aged less than six months and pregnant women.
DHA-P versus artemether-lumefantrine
In Africa, over 28 days follow-up, DHA-P is superior to artemether-lumefantrine at preventing further parasitaemia (PCR-unadjusted treatment failure: RR 0.34, 95% CI 0.30 to 0.39, nine trials, 6200 participants, high quality evidence), and although PCR-adjusted treatment failure was below 5% for both ACTs, it was consistently lower with DHA-P (PCR-adjusted treatment failure: RR 0.42, 95% CI 0.29 to 0.62, nine trials, 5417 participants, high quality evidence). DHA-P has a longer prophylactic effect on new infections which may last for up to 63 days (PCR-unadjusted treatment failure: RR 0.71, 95% CI 0.65 to 0.78, two trials, 3200 participants, high quality evidence).
In Asia and Oceania, no differences have been shown at day 28 (four trials, 1143 participants, moderate quality evidence), or day 63 (one trial, 323 participants, low quality evidence).
Compared to artemether-lumefantrine, no difference was seen in prolonged QTc (low quality evidence), and no cardiac arrhythmias were reported. The frequency of other adverse events is probably similar with both combinations (moderate quality evidence).
DHA-P versus artesunate plus mefloquine
In Asia, over 28 days follow-up, DHA-P is as effective as artesunate plus mefloquine at preventing further parasitaemia (PCR-unadjusted treatment failure: eight trials, 3487 participants, high quality evidence). Once adjusted by PCR to exclude new infections, treatment failure at day 28 was below 5% for both ACTs in all eight trials, but lower with DHA-P in two trials (PCR-adjusted treatment failure: RR 0.41 95% CI 0.21 to 0.80, eight trials, 3482 participants, high quality evidence). Both combinations contain partner drugs with very long half-lives and no consistent benefit in preventing new infections has been seen over 63 days follow-up (PCR-unadjusted treatment failure: five trials, 2715 participants, moderate quality evidence).
In the only trial from South America, there were fewer recurrent parastaemias over 63 days with artesunate plus mefloquine (PCR-unadjusted treatment failure: RR 6.19, 95% CI 1.40 to 27.35, one trial, 445 participants, low quality evidence), but no differences were seen once adjusted for new infections (PCR-adjusted treatment failure: one trial, 435 participants, low quality evidence).
DHA-P is associated with less nausea, vomiting, dizziness, sleeplessness, and palpitations compared to artesunate plus mefloquine (moderate quality evidence). DHA-P was associated with more frequent prolongation of the QTc interval (low quality evidence), but no cardiac arrhythmias were reported.
In Africa, dihydroartemisinin-piperaquine reduces overall treatment failure compared to artemether-lumefantrine, although both drugs have PCR-adjusted failure rates of less than 5%. In Asia, dihydroartemisinin-piperaquine is as effective as artesunate plus mefloquine, and is better tolerated.
PLAIN LANGUAGE SUMMARY
Dihydroartemisinin-piperaquine for treating uncomplicated malaria
This review summarises trials evaluating the effects of dihydroartemisinin-piperaquine (DHA-P) compared to other artemisinin-based combination therapies recommended by the World Health Organization. After searching for relevant trials up to July 2013, we included 27 randomized controlled trials, enrolling 16,382 adults and children and conducted between 2002 and 2010.
What is uncomplicated malaria and how might dihydroartemisinin-piperaquine work
Uncomplicated malaria is the mild form of malaria which usually causes a fever, with or without headache, tiredness, muscle pains, abdominal pains, nausea, and vomiting. If left untreated, uncomplicated malaria can develop into severe malaria with kidney failure, breathing difficulties, fitting, unconsciousness, and eventually death.
DHA-P is one of five artemisinin-based combination therapies the World Health Organization currently recommends to treat malaria. These combinations contain an artemisinin component (such as dihydroartemisinin) which works very quickly to clear the malaria parasite from the person's blood, and a longer acting drug (such as piperaquine) which clears the remaining parasites from the blood and may prevent new infections with malaria for several weeks.
What the research says
DHA-P versus artemether lumefantrine
In studies of people living in Africa, both DHA-P and artemether-lumefantrine are very effective at treating malaria (high quality evidence). However, DHA-P cures slightly more patients than artemether-lumefantrine, and it also prevents further malaria infections for longer after treatment (high quality evidence). DHA-P and artemether-lumefantrine probably have similar side effects (moderate quality evidence).
DHA-P versus artesunate plus mefloquine
In studies of people living in Asia, DHA-P is as effective as artesunate plus mefloquine at treating malaria (moderate quality evidence). Artesunate plus mefloquine probably causes more nausea, vomiting, dizziness, sleeplessness, and palpitations than DHA-P (moderate quality evidence).
Overall, in some people, DHA-P has been seen to cause short term changes in electrocardiographs tracing the conduction of the heart rhythm (low quality evidence), but these small changes on the electrocardiograph resolved within one week without serious consequences.