Pfs230D1-CRM197 + R21

Pfs230D1-CRM197 + R21 is a **combination malaria vaccine candidate** currently under clinical investigation for malaria prevention and transmission blocking. The formulation combines two antigens: **Pfs230D1-CRM197**, a protein conjugate vaccine targeting the sexual stage antigen Pfs230 (crucial for parasite transmission in mosquitoes), conjugated to CRM197 (a nontoxic mutant of diphtheria toxin, used to enhance immunogenicity); and **R21**, a recombinant protein nanoparticle vaccine targeting the circumsporozoite protein (CSP) of Plasmodium falciparum, a primary target for pre-erythrocytic malaria immunity. Both antigens are co-administered with the Matrix-M1 adjuvant for improved immune response. Mechanism of action: - **Pfs230D1-CRM197** induces transmission-blocking antibodies that target gametocytes, preventing fertilization and development of the malaria parasite in the mosquito, thereby interrupting transmission within the population[4]. - **R21** generates antibodies to the CSP repeat region, aiming to prevent infection by targeting sporozoites before they invade liver cells (pre-erythrocytic stage). Primary indication: malaria prevention and transmission blocking. Development is led by academic and non-profit institutions partnered with vaccine manufacturers. Clinical evaluation (Phase 1/2) is ongoing in African adults and children[1][2][3].

Other names

Pfs230D1 + R21Pfs230D1-CRM197/R21