Names Of Malaria Vaccines in Different Stages
Here are the malaria vaccine names
- RTS,S/AS01, Brand name Mosquirix
- R21/Matrix-M malaria vaccine
- PfSPZ Vaccine
- Novartis’s CVac
- mRNA based Vaccine by SII snd Oxford
- SPf66 Malaria Vaccine
- CSP (Circum-Sporozoite Protein) Vaccine
- NYVAC-Pf7 Multi-Stage Vaccine
RTS,S/AS01, Brand name Mosquirix
Key Points
- RTS,S/AS01, brand name Mosquirix, is the first malaria vaccine approved for public use.
- It requires at least three doses in infants by age 2, with a fourth dose extending the protection for another 1–2 years.
- The vaccine reduces hospital admissions from severe malaria by around 30%.
- RTS,S was developed by PATH Malaria Vaccine Initiative (MVI) and GlaxoSmithKline (GSK) with support from the Bill and Melinda Gates Foundation.
- It is a recombinant vaccine containing the Plasmodium falciparum circumsporozoite protein (CSP) from the pre-erythrocytic stage.
- The CSP antigen induces antibody production to prevent the invasion of hepatocytes and triggers a cellular response to destroy infected hepatocytes.
- The vaccine initially faced challenges in trials due to its poor immunogenicity.
- To address this, RTS,S fused the CSP protein with a surface antigen from hepatitis B virus, creating a more potent and immunogenic vaccine.
- In trials, when tested with added adjuvants (monophosphoryl A and QS21), the vaccine provided protective immunity to 7 out of 8 volunteers challenged with P. falciparum.
- RTS,S was engineered using genes from the outer protein of the P. falciparum malaria parasite, a portion of a hepatitis B virus, and a chemical adjuvant to boost the immune response.
- Infection prevention is achieved by inducing high antibody titers that block the parasite from infecting the liver.
- In November 2012, a Phase III trial of RTS,S found that it provided modest protection against both clinical and severe malaria in young infants.
Read Also : Disease X: The next Pandemic
R21/Matrix-M malaria vaccine
Key points
- The most effective malaria vaccine is R21/Matrix-M, demonstrating a 77% efficacy in initial trials.
- It is the first vaccine to meet the World Health Organization’s goal of a malaria vaccine with at least 75% efficacy.
- R21/Matrix-M was developed through collaboration involving the Jenner Institute at the University of Oxford, the Kenya Medical Research Institute, the London School of Hygiene and Tropical Medicine, Novavax, and the Serum Institute of India.
- The trials took place at the Institut de Recherche en Sciences de la Santé in Nanoro, Burkina Faso, with Halidou Tinto as the principal investigator.
- The R21 vaccine utilizes a circumsporozoite protein (CSP) antigen, at a higher proportion than the RTS,S vaccine. It shares the same HBsAg-linked recombinant structure but contains no excess HBsAg.
- It includes the Matrix-M adjuvant, also used in the Novavax COVID-19 vaccine.
- A phase II trial reported in April 2021 showed a vaccine efficacy of 77% and significantly higher antibody levels compared to the RTS,S vaccine.
- A booster shot of R21/Matrix-M given 12 months after the primary three-dose regimen maintains high efficacy against malaria, providing protection against symptomatic malaria for at least 2 years.
- A phase III trial with 4,800 children across four African countries reported in November 2022 demonstrated a vaccine efficacy of 74% against a severe malaria episode.
- Further data from multiple studies is being collected.
- As of April 2023, data from the phase III study had not been formally published, but late-stage data from the study was shared with regulatory authorities.
PfSPZ Vaccine
- Developed by Sanaria.
- Uses radiation-attenuated sporozoites to trigger an immune response.
- Promising clinical trial results, with over 80% protection in trials across Africa, Europe, and the US.
- Criticized for potential challenges in large-scale production and delivery in Africa due to the need for storage in liquid nitrogen.
- Granted fast track designation by the U.S. Food and Drug Administration in September 2016.
- Phase III trial in Bioko announced in April 2019, scheduled to begin in early 2020.
- The trial is still in process during 2022 and 2023 and hoped to get the final result in late 2024.
Check the Source of Article Here :
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9396563/
Novartis’s CVac
Novartis completed a Phase 1 clinical trial for CVac, a whole-parasite malaria vaccine that has shown promise in terms of safety and tolerability.
mRNA based Vaccine Testing
Serum Institute of India partnered with the University of Oxford to develop an mRNA-based malaria vaccine, leveraging the same technology used for COVID-19 vaccines.
Read Also: Immortality Through Cryonics
SPf66 Malaria Vaccine
- Synthetic peptide-based vaccine developed by the Manuel Elkin Patarroyo team in Colombia.
- Extensively tested in endemic areas during the 1990s.
- Clinical trials revealed insufficient effectiveness, with only 28% efficacy in South America.
- Showed minimal to no efficacy in Africa.
- Demonstrated no protective effect in the largest placebo-controlled randomized trial in South East Asia.
- Ultimately, the vaccine was abandoned due to its limited effectiveness.
CSP (Circum-Sporozoite Protein) Vaccine
- Based on the circumsporozoite protein, with an additional recombinant protein covalently bound to a Pseudomonas aeruginosa toxin.
- Initially appeared promising and underwent trials.
- Demonstrated a complete lack of protective immunity in those inoculated during an early stage.
- Study group in Kenya showed an 82% incidence of parasitaemia, while the control group had an 89% incidence.
- Intended to induce an increased T-lymphocyte response, but this was not observed.
NYVAC-Pf7 Multi-Stage Vaccine
- Utilizes different technology, encompassing seven P. falciparum antigenic genes from various lifecycle stages.
- Antigens include CSP and PfSSP2 (from the sporozoite phase), LSA1 (liver stage antigen), three from the erythrocytic stage, and one sexual stage antigen, Pfs25.
- Rhesus monkey trials showed positive results, with 4 out of the 7 antigens generating specific antibody responses (CSP, PfSSP2, MSP1, and Pfs25).
- Human trials demonstrated cellular immune responses in over 90% of subjects but had low antibody responses.
- Some candidates exhibited complete protection against P. falciparum after vaccination, prompting ongoing trials.
Other Vaccine Developer
GlaxoSmithKline, Plc., Novartis AG, Takeda Pharmaceutical Company, Sanaria Inc., Merck & Co., Johnson & Johnson, Pfizer Inc., Serum Institute of India Private Limited, Bharat Biotech International Limited, Moderna Inc are some of the leading players operating in the Global Malaria Vaccine Market.
Read Also : Lead Poisoning