Event Highlights from the VivAccess Hosted Symposium at Virtual ASTMH: Accelerating New Tools for Radical Cure of Vivax Malaria from Clinical and Operational Research to Policy

Tafenoquine, a single-dose treatment for the prevention of relapse, and new diagnostics could transform treatment and elimination prospects for P. vivax malaria. Widespread use of tafenoquine depends on the ability to identify all cases of P. vivax malaria and safely screen patients’ glucose-6-phosphate dehydrogenase (G6PD) enzyme activity. The potential of this expanded access will only be realized when accurate, reliable, point-of-care (POC) malaria and G6PD testing are concurrently adopted in vivax-endemic settings.

This potential transformation was the subject of the VivAccess ASTMH symposium, held on 18th October 2020. The symposium explored the modeling, clinical, and operational research platforms that have been established to generate the tools and data that can be considered by normative authorities in making policy decisions to support future elimination goals. 

The symposium was chaired by Dr Caroline Lynch of Medicines for Malaria Venture and Dr Jimee Hwang from the President’s Malaria Initiative (PMI). It addressed three themes:

• the advent of new diagnostics to support improved case management;
• the potential impact of new tools on P. vivax malaria;
• and the operational feasibility of integrating new P. vivax products to achieve best clinical practices and elimination goals.

Speakers:

• Dr Allison Golden, presented an assessment of different biomarkers for P. vivax infection used as targets of new diagnostics to inform case management and elimination.
• Dr Daniel Yilma presented a pooled analysis of performance and usability data generated for the SD Biosensor STANDARD G6PD test using a clinical research platform for the validation of novel G6PD tests established across Brazil, Ethiopia and the USA.
• Dr Michael White presented the work undertaken by Institut Pasteur and Fiocruz on a transmission model of the rollout and potential impact of tafenoquine on P. vivax in Brazil, adapted from a mathematical model developed for Papua New Guinea. This modeling estimated the potential direct benefit to patients who receive treatment and the indirect benefit by preventing onward transmission, thereby reducing population-level transmission in the entire community.
• Dr Marcus Lacerda, presented the approach for the upcoming TRuST study in Brazil that will assess the operational feasibility of providing appropriate radical cure (tafenoquine or primaquine) after quantitative G6PD testing under field conditions and the practicalities of implementation. TRuST is jointly sponsored by the Ministry of Health and Medicines for Malaria Venture (MMV) and aims to generate evidence that can be considered by normative authorities to make policy decisions.
• Dr Wint Phyo Than, deputy director of the National Malaria Control Programme in Myanmar, concluded the series of presentations by outlining the pathway for national level policy adoption of new tools for radical cure. This included the key considerations and priorities to be addressed to ensure future adoption and deployment of the new tools in Myanmar is effective in supporting the Ministry of Health and Sports (MOHS) to achieve their goal of malaria elimination.

The presentations were followed by a question and answer session with participants facilitated by the co-chairs.  There was a discussion around the safety of vivax treatments, as well as the impact of heterogeneous transmission on the modeling work led by Michael White. Dr Yilma elaborated on some of the limitations of the Ethiopian study presented including the relatively low sample size of health workers. A question was asked as to whether there is a need for new tools to eliminate P. vivax in Myanmar given the significant declines in cases in recent years. Dr Wint Phyo Than, responded that new tools are needed to address treatment adherence which remains a key concern for the national programme.