A quality control program within a clinical trial Consortium for PCR protocols to detect Plasmodium species.

Malaria parasite infections that are only detectable by molecular methods are highly prevalent and represent a potential transmission reservoir. The methods used to detect these infections are not standardized, and their operating characteristics are often unknown. We designed a proficiency panel of Plasmodium spp. in order to compare the accuracy of parasite detection of molecular protocols used by labs in a clinical trial consortium. Ten dried blood spots (DBSs) were assembled that contained P. falciparum, P. vivax, P. malariae, and P. ovale; DBSs contained either a single species or a species mixed with P. falciparum. DBS panels were tested in 9 participating laboratories in a masked fashion. Of 90 tests, 68 (75.6%) were correct; there were 20 false-negative results and 2 false positives. The detection rate was 77.8% (49/63) for P. falciparum, 91.7% (11/12) for P. vivax, 83.3% (10/12) for P. malariae, and 70% (7/10) for P. ovale. Most false-negative P. falciparum results were from samples with an estimated ≤ 5 parasites per µl of blood. Between labs, accuracy ranged from 100% to 50%. In one lab, the inability to detect species in mixed-species infections prompted a redesign and improvement of the assay. Most PCR-based protocols were able to detect P. falciparum and P. vivax at higher densities, but these assays may not reliably detect parasites in samples with low P. falciparum densities. Accordingly, formal quality assurance for PCR should be employed whenever this method is used for diagnosis or surveillance. Such efforts will be important if PCR is to be widely employed to assist malaria elimination efforts.

Safety, efficacy and population pharmacokinetics of fixed-dose combination of artesunate-mefloquine in the treatment of acute uncomplicated Plasmodium falciparum malaria in India.

BACKGROUND & OBJECTIVES: India has switched over to artemisinin-based combination therapy (ACT) for the treatment of acute uncomplicated Plasmodium falciparum malaria and the ACT used in the national programme is artesunate + sulphadoxine-pyrimethamine. Since the efficacy of ACT is dependent also on the partner drug, there is a need to evaluate and deploy multiple ACTs. METHODS: This multicentre, single-arm, open-label clinical trial was carried out to assess the efficacy, safety and population pharmacokinetics of a fixed dose combination (FDC) artesunate mefloquine (ASMQ) in P. falciparum infected, Indian adults at Panjim, Goa, and Mangalore, Karnataka between December 2007 and November 2008. RESULTS: A total of 77 patients (males 74) were screened and enrolled: 42 at Goa and 35 at Mangalore with a median age of 25 yr (range 18-55 yr). One patient failed in treatment on D53, a PCR proven new infection, seven developed recurrent vivax parasitaemia and 11 did not have a parasitological endpoint. By per protocol analysis, the D63 cure rate was 58/59 (98.3; 95% C.I. 90.9-99.9%), and 58/58, with PCR correction. ASMQ was well-tolerated and no serious adverse events were reported. INTERPRETATION & CONCLUSION: The study showed that the ASMQ FDC was efficacious and well-tolerated for the treatment of acute, uncomplicated P. falciparum malaria in highly endemic, chloroquine resistant areas of Goa and Mangalore. It is a viable option for India.

Arterolane maleate plus piperaquine phosphate for treatment of uncomplicated Plasmodium falciparum malaria: a comparative, multicenter, randomized clinical trial.

BACKGROUND: Artemisinin-based combination therapy is the first-line treatment for uncomplicated falciparum malaria. This study assessed the antimalarial efficacy and safety of a combination of 150 mg of arterolane maleate and 750 mg of piperaquine phosphate (AM-PQP) in comparison to Coartem (artemether and lumefantrine) in patients with acute uncomplicated P. falciparum malaria. METHODS: In this open-label, randomized, multicentric, parallel group clinical trial, 240 patients were randomized to receive AM-PQP (160 patients) or Coartem (80 patients). Patients with P. falciparum monoinfection and initial parasite densities ranging from 1000 to 100 000 asexual parasites/µL of blood were followed for 28 days. Polymerase chain reaction-corrected adequate clinical and parasitologic response on day 28, parasite clearance time, and fever clearance time were evaluated. RESULTS: A total of 151 (94.4%) of 160 patients in the AM-PQP group completed the trial, while 77 (96.3%) of 80 patients in the Coartem group completed the trial. No treatment failure was noted in the AM-PQP group, while one patient receiving Coartem failed treatment on day 28. There was no difference in the median parasite clearance time (30 hours in both groups) or median fever clearance time (24 hours in both groups) after administration of the 2 study treatments. CONCLUSIONS: The available data support the evaluation of a drug combination in a larger population as a fixed-dose combination. Clinical Trials Registration. CTRI/2007/091/000031.

Monitoring antimalarial drug resistance in India via sentinel sites: outcomes and risk factors for treatment failure, 2009-2010.

OBJECTIVE: To describe India's National Antimalarial Drug Resistance Monitoring System, measure the efficacy of first-line malaria treatments, and determine risk factors for treatment failure. METHODS: In 2009-2010, prospective studies with 28 days of follow-up were conducted at 25 sentinel sites. Patients infected with Plasmodium falciparum were given artesunate plus sulfadoxine-pyrimethamine (AS+SP); those infected with P. vivax were given chloroquine. Polymerase chain reaction was used to distinguish post-treatment reinfection from treatment failure. Isolates of P. falciparum were checked for dhfr and dhps mutations. FINDINGS: Overall, 1664 patients were enrolled. Kaplan-Meier survival analysis showed an efficacy of 98.8% for AS+SP. Most patients with P. falciparum parasitaemia cleared their parasitaemias within 24 hours of treatment initiation, but six, including four with treatment failure, remained parasitaemic after 72 hours. Double mutants in dhfr were found in 68.4% of the genotyped isolates. Triple or quadruple mutants in dhfr and mutations in dhps were rare. A daily dose of artesunate of < 3 mg per kg of body weight, age of less than 5 years, and fever at enrolment were associated with an increased risk of treatment failure. Chloroquine remained 100% efficacious and generally cleared P. vivax parasitaemias within 48 hours. Vomiting (seen in 47 patients) was the most common adverse event. CONCLUSION: India's National Antimalarial Drug Resistance Monitoring System provides wide coverage. The first-line antimalarials used in the country remain safe and efficacious. The treatment of malaria in young children and the relative benefits of age- and weight-based dosing need further exploration.