E156 Micro-Paper · Africa Clinical Trials

Vaccine Equity Audit

Africa manufactures less than 1% of the vaccines it uses, and vaccine trial dist...

Africa Trials
177
US Trials
3,486
Gap Ratio
20x
Nations
54
Africa hosted 177 vaccine trials versus 3,486 in the United States, a 20-fold disparity in research investment.
Phase Distribution Africa US Europe Phase 1 33 218.2 281.9 Phase 2 45 275.9 403.4 Phase 3 36 534.8 255.5 Phase 4 6 31.2 52.5 534.8 6
Vaccine Equity Audit by Country Egypt: 11752 Algeria: N/A Morocco: 162 Tunisia: 540 Senegal: N/A Ghana: 261 Nigeria: 379 Cameroon: N/A DRC: N/A Ethiopia: 302 Kenya: 788 Uganda: 809 Tanzania: 460 Rwanda: N/A South Africa: 3654 Egy 11752 Sou 3654 Uga 809 Ken 788 Tun 540 162 11752
No data
Contribution Breakdown 11752 Egypt 3654 South Afri 809 Uganda 788 Kenya 540 Tunisia 2814 Others
Vaccine Equity Audit Lorenz Curve 0% 0% 25% 25% 50% 50% 75% 75% 100% 100% Gini = 0.711
Research Profile Volume Growth Phase3 Complete Diversity
Enrollment Distribution Africa Reference 20000 40000 60000 80000
Growth 2010-2026 Before After Africa 0 0 US 0 0 Europe 0 0
Why It Matters

Africa manufactures less than 1% of the vaccines it uses, and vaccine trial distribution reflects this dependency — most trials are sponsored by foreign manufacturers testing products for global markets.

In the burden-versus-investment landscape of African health research, does the distribution of vaccine trials across African nations reveal a systematic research gap? This cross-sectional audit evaluated 23,873 African and 190,644 United States interventional trials registered on ClinicalTrials.gov through April 2026. Investigators computed the Herfindahl-Hirschman concentration index as the primary estimand using registry metadata for each nation. Africa hosted 177 vaccine trials (0.7% of its portfolio) compared to 3,486 in the United States, yielding a 0.0-fold disparity in per-population investment. The Herfindahl-Hirschman index reached 3472.872, exceeding the threshold of 0.25 that indicates a highly concentrated distribution. These results expose a fundamental mismatch between where disease burden falls and where research investment flows across Africa. Interpretation is constrained by missing sub-national data and the exclusion of observational studies from the analysis.
Question

In the burden-versus-investment landscape of African health research, does the distribution of vaccine trials across African nations reveal a systematic research gap?

Dataset

This cross-sectional audit evaluated 23,873 African and 190,644 United States interventional trials registered on ClinicalTrials.

Method

gov through April 2026.

Primary Result

Investigators computed the Herfindahl-Hirschman concentration index as the primary estimand using registry metadata for each nation.

Robustness

Africa hosted 177 vaccine trials (0.

Interpretation

7% of its portfolio) compared to 3,486 in the United States, yielding a 0.

Boundary

0-fold disparity in per-population investment.

Extra

The Herfindahl-Hirschman index reached 3472.

Extra

872, exceeding the threshold of 0.

Extra

25 that indicates a highly concentrated distribution.

Extra

These results expose a fundamental mismatch between where disease burden falls and where research investment flows across Africa.

Extra

Interpretation is constrained by missing sub-national data and the exclusion of observational studies from the analysis.