R21/Matrix-M

The R21/Matrix-M vaccine is a groundbreaking vaccine developed to prevent malaria, specifically targeting the Plasmodium falciparum parasite, which is the deadliest malaria parasite globally.

Developed by the University of Oxford and manufactured by the Serum Institute of India, it became the second malaria vaccine ever to be recommended by the World Health Organization (WHO) in October 2023.

Key Features of R21?

• High Efficacy: In clinical trials, the vaccine showed a 75% reduction in symptomatic malaria cases when administered before the peak transmission season. In areas where malaria is present year-round, it showed approximately 67–68% efficacy.
• Target Population: It is primarily designed for children, who are the most vulnerable to the disease. It is typically administered in a 3-dose primary series starting from 5 months of age, followed by a booster dose 12 months later.
• Cost-Effective: One of its greatest advantages is its price, estimated at $2–$4 per dose, making it significantly more affordable than the first malaria vaccine (RTS,S).
• Mass Production: The Serum Institute of India has the capacity to produce over 100 million doses per year, which is crucial for meeting the massive global demand.

How It Works?

The R21 vaccine is a “subunit” vaccine. It works by teaching the immune system to recognize the circumsporozoite protein (CSP), which sits on the surface of the malaria parasite.

1. Intercepting the Parasite: It targets the parasite at the sporozoite stage—the moment it enters the human body through a mosquito bite.
2. Preventing Liver Entry: By creating antibodies against the CSP, the vaccine prevents the parasite from reaching and infecting the liver, where it would otherwise multiply and enter the bloodstream.
3. The Adjuvant: It uses Novavax’s Matrix-M adjuvant, a special ingredient that boosts the body’s immune response, making the protection stronger and longer-lasting.

R21 vs. RTS,S (Mosquirix):

While both vaccines target the same protein, there are a few notable differences: