Table 4 Example of the cyclical work process of the Vivax Working Group (treatment theme)
Identify knowledge gaps | Two literature reviews were conducted on the treatment of P. vivax. The first review addressed the current knowledge gaps for the radical cure of P. vivax infection [32]. It revealed that treatment with low dose primaquine is not consistently effective in all geographical areas. The review further demonstrated that higher doses of primaquine offer significant benefits. However there are few data available and the review therefore concluded that these findings would need to be confirmed in a range of endemic settings, and amongst high-risk patients. The second review was conducted to define the extent and evidence regarding chloroquine resistant P. vivax [16]. The review suggests that chloroquine resistance has been underappreciated, with evidence for reduced susceptibility in many areas where vivax is endemic. It concluded that standardized methodologies and the development of novel tools are required for the more precise quantification of drug efficacy. |
Build consensus | In 2011 the VxWG group convened in Jiangsu, China to discuss options for a multicentre trial assessing the efficacy of vivax treatment options. During the meeting the methodological challenges of crafting appropriate study designs were discussed, but no consensus for a common protocol was reached. Participants did, however, agree to fund 3 pilot studies with the aim of generating information that would guide the study design for larger multicentred trials. |
Gather the evidence | One of the three clinical studies was performed in Sabah, Malaysia to assess efficacy of early parasite clearance of the current first line treatment, chloroquine compared with the artemisinin combination therapy (ACT) artesunate–mefloquine. The study followed patients up for 1 year to assess efficacy of primaquine in both study arms. Preliminary results show that high levels of chloroquine resistant P. vivax are now present in this region, and suggest that a change to a unified ACT protocol for all Plasmodium species may be warranted. |
Change practice | Preliminary data from this study have been presented to the Malaysian Ministry of Health, and are currently under review. |