MICA: A bioequivalent study to WHO prequalify a new 15 mg primaquine tablet

Primaquine (PQ) is fundamental to eliminating malaria by blocking the transmission of Plasmodium falciparum between humans and mosquitoes and killing P. vivax liver hypnozoites to prevent relapses, the main cause of the continuing vivax burden. PQ is barely used by malaria control programmes (MCPs) for two main reasons: (i) G6PD deficiency testing, required before PQ radical cure is prescribed, is not widely available, and (ii) easy-to-use regimens of quality assured (QA) PQ tablets covering the age spectrum do not exist, thus excluding children, a key vulnerable group. Cognizant of this substantial public health gap, the WHO called for the prequalification of 2.5, 3.75 and scored 5, 7.5 & 15 mg tablets and detailed the required process. Prequalification starts with prequalifying a scored generic 15 mg tablet through a bioequivalence (BE) study that: (i) uses the international PQ reference, the Sanofi 15 mg tablet, (ii) is conducted to WHO standards and passes WHO inspection, (iii) establishes bioequivalence, and (iv) is followed by dossier submission to the WHO. Prequalifying the lower tablet strengths does not require more BE studies but is achieved by applying for biowaivers whereby these tablets are shown to be pharmaceutically equivalent (proportionality, dissolution properties) to the generic 15 mg tablet. Prequalification makes registration in malaria endemic countries easier and allows PQ bulk purchase and deployment using Global Fund money. We seek funds for the BE study to engage IPCA, the industrial partner, through a MICA which provides the necessary legal framework for the planned work. Developing QAPQ as a public good dovetails with our current work of designing evidenced-based, allometrically scaled PQ regimens for transmission blocking and radical cure and bespoke to enhance patient adherence. Thus, increasing access to QAPQ will have a significant impact on malaria elimination.

Project details

Drug-based Strategies
Product Development

Feb 2021 — Jul 2023

$475,735

United Kingdom