The goal of malaria elimination highlights the importance of delivering safe and effective radical cure of malaria in regions endemic for P. vivax. Vivax’s propensity to recur and to form dormant liver stages (hypnozoites) requires the provision of treatment of both the blood and liver stages of the parasite. Currently, the only widely available drug to eliminate hypnozoites from the human host is primaquine (PQ). The Word Health Organizations (WHO) treatment guidelines recommend that PQ is administered over 14 days to reduce the risk of severe haemolysis. However there are still concerns about its safety, which hamper its widescale use.
Routinely-collected hospital surveillance data was used in a retrospective cohort study design to define the risk of serious adverse events following administration of unsupervised primaquine without prior G6PD testing. Patients presenting to any department at Rumah Sakit Mitra Masyarakat with microscopically confirmed P. vivax parasitaemia (either as a mono-infection or part of a mixed infection) regardless of presence or absence of symptoms are included in the analyses.
The following outcomes will be presented: the cumulative risk of hospital admission within 30 days after initiation of treatment of P. vivax comparing the different primaquine (PQ) dosing (no PQ, low dose PQ and high dose PQ), the cumulative risk of death within 30 days after presentation with P. vivax comparing the different PQ dosing arms, the cumulative risk of representation within 30 days of treatment of P. vivax comparing the different PQ dosing arms. We will also present a subgroup analysis of individuals readmitted to hospital assessing the absolute fall of Hb between enrolment and readmission in g/dl, fractional fall between enrolment and readmission, and the risk of falling below 7g/dl and risk of having a fractional fall >25%. The analysis will be completed with a description of events at the time of death and identification of potential relationship to PQ dosing arms.