WHO review of malaria vaccine clinical development
Published: March 2024
WHO analyzed the pipeline of malaria vaccines that were in phase I-IV of clinical development (as of December 2023). Products are reported by vaccine status (active/inactive), highest phase of clinical development, target malaria species, target life cycle stage, vaccine platform, target antigen, and adjuvant. Trials are reported by countries where trials are conducted, trial status, WHO Region and income group. See below for details on the scope, analysis, and limitations
What you see | Scope, analysis and limitations | Data sources | Previous versions
What you see
The data visualization shows the:
- Number of malaria vaccines by:
- WHO review status (prequalified, recommended) (chart A)
- Vaccine status and highest phase of development (chart B)
- Target malaria species (chart C)
- Target life cycle stage (chart D)
- Vaccine platform (chart E)
- Target antigen (chart F)
- Vaccine adjuvant (chart G)
- Number of malaria vaccine trials by:
- Countries where trials are conducted, including whether trial involves controlled human malaria infection (chart H)
- Trial status (ongoing, completed, or withdrawn) (chart H.1)
- WHO region (chart H.2)
- Income group (chart H.3)
- List of vaccines and trials by vaccine status, trial status, and phase, with further information on each product (hover on a phase to open a pop-up window for additional information in chart I)
Products can also be viewed according to vaccine status (select “Active” or “Inactive” options using top left tick boxes).
Note: A vaccine may target multiple species, life cycle stages, antigens and/or use multiple vaccine platforms and adjuvants - the numbers displayed in these charts may total to more than the total number of vaccines.
Points to note:
- Out of 133 malaria vaccines that have been in clinical development:
- Two vaccines have been WHO prequalified and recommended - RTS,S/AS01E and R21/Matrix-M (chart A).
- A total of 38 vaccines are in active stage (select the "Active" vaccine status tick box at the top left and see the number of vaccines).
- Of the 38 vaccines in an "active" status of clinical development (select the “Active” vaccine status tick box at the top left):
- Over half (22; 58%) are in phase I, one third (14; 37%) are in phase II, one in phase III, and one (RTS,S/AS01E) in phase IV (chart B).
- 87% (33) target Plasmodium falciparum and 13% (5) target Plasmodium vivax (chart C).
- Approximately half (17; 45%) target the pre-erythrocytic stage, followed by the blood stage (15; 40%) and the sexual stage (9; 24%) (chart D).
- Two thirds are recombinant subunit vaccines (25; 66%). This is followed by virus-like particles (7; 18%) and recombinant viral-vectored (5; 13%) vaccine platforms (chart E).
- 17 different antigens have been targeted, of which PfCSP is the most common (13; 34%) (chart F).
- Out of nine different adjuvants used, the two adjuvants used in the two WHO recommended vaccines are AS01E (RTS,S) and Matrix M1 (R21) (select phase IV and phase III in chart B and see chart G respectively).
- A total of 221 malaria vaccine trials have been completed or started since 2002 (see top right), of which:
- 24 trials are ongoing for vaccines in active development (select “Active” vaccine status on the top left and see chart H.1).
- Nearly half (102; 46%) have been completed or are ongoing in 13 countries in the WHO Africa region (reset previous filter, select “Africa” in chart H.2 and view map in chart H).
To explore the data further
- Select the vaccine status (active, inactive) and phase of development (phase I-IV) and further stratify the data according to target malaria species, target life cycle stage, vaccine platform, target antigen or adjuvant – or a combination of elements (e.g., by clicking on a bar in a chart or cell in a table) – to display the corresponding data in the other charts.
- Hover the cursor on a bar or a cell in a table to see more information in a pop-up window.
- Hold the ‘Ctrl’ key on your keyboard to select more than one option.
- Undo a selection by clicking ‘undo’ or ‘reset’ near the bottom of the page or by clicking the same element again.
Scope, analysis and limitations of the data
Scope
- This pipeline analysis focuses on vaccines under development against all Plasmodium species of malaria. It covers information available as of December 2023 and is limited to products in phases I-IV of clinical development.
- Vaccines that have not yet reached phase IV development are considered vaccine candidates.
- Vaccines in phases I to IV that were active or inactive/discontinued for which development occurred in the last 10 years were included. Research on a vaccine was considered to be active if any clinical development activity had taken place in the last 3 years, they were listed on the developer’s pipeline as active, or they were confirmed to be active by consulted experts. Candidates were identified as inactive if no clinical development activity had been identified in the last 3 years or experts identified them as inactive.
- Use of a different adjuvant is considered a distinct vaccine but does not necessarily indicate a different generation vaccine.
- Different dosing regimens are not considered to be a distinct vaccine.
- Monoclonal antibodies or products used for passive immunization were not included in this analysis.
Analysis
Data collection involved the following sources:
- Clinical trials registries: the International Clinical Trials Registry Platform (ICTRP), clinicaltrials.gov.
- Status of health products in the pipeline from the WHO Global Observatory on Health Research and Development, based on Springer Nature AdisInsight data source.
A draft list of the clinical pipeline was generated and shared for feedback with stakeholders across industry, academia, funding agencies, policymakers, and other experts. Comments were reviewed and incorporated into the final data set and report.
Limitations of the data
- This analysis relies on data available in the public domain or from contacted experts.
- Up-to-date data on some vaccines was not identified.
The WHO Secretariat welcomes additional information and/or feedback on the data presented in this analysis. Feedback should be sent to malvac@who.int.