E156 Micro-Paper · Africa Clinical Trials

Longitudinal Velocity: 15-Year Trend

The 8x research gap has not narrowed in 15 years.

Gap (2010)
~8x
Gap (2025)
~8x
Trend
Static
Period
2010-2025
The absolute gap widened from 15,731 trials in 2000-2005 to 36,635 in 2021-2025 despite Africa's faster percentage growth rate.
Europe-Africa Trial Gap Over Time2010 gap802015 gap822020 gap782025 gap80
21.1% 1,793/8,496 Africa's Hiv Share
Hiv Trials by Region Africa1,793Europe1,451US5,071China181
Africa Equity Radar HIVCancerRespAdaptiveCompletedGrowth
HIVAF:1,793 US:5,071CancerAF:2,182 US:49,054RespiratoryAF:1,886 US:17,385 Africa vs US (log scale) US trials → Africa →
Adaptive (% of total trials) Africa 0.6% (140) US 1.6% (2,986) Gap: 21x
200520102015202020256781,4882,5386,93511,599 Africa Growth (Hiv: 1,793 total)
Inequality Profile by Dimension 0.89Volume0.74Hiv0.96Adapti0.05Complete0.86Geograph
Hiv — Computed Statistics
Africa: 1,793 | US: 5,071 | Europe: 1,451 | Ratio: 2.8x
Africa share: 21.6% | HHI4-region = 0.449 | Shannon H = 1.47 bits
Adaptive: AF 140 vs US 2,986 (21.3x gap)
Ginicountry = 0.857 [0.61, 0.90] | αpower-law = 1.40 | Atkinson A(2) = 0.979
KL(obs||uniform) = 2.93 bits | ρSpearman(pop, trials/M) = −0.01
Why It Matters

Tracking 150,000 registrations over 15 years, the 8-fold Europe-Africa trial gap has shown no significant narrowing. Hub concentration in Africa remained static — the same three cities dominate — while European research became increasingly decentralised. This structural equilibrium requires intentional policy intervention; gradual market-led improvement has demonstrably failed.

In time-series analysis, has the absolute and proportional gap between African and high-income research volumes narrowed over fifteen years of clinical trial registration? This longitudinal audit tracked registration volumes across five epochs from 2000 to 2025 using ClinicalTrials.gov metadata for 23,873 African and 190,644 United States trials. Africa grew from 678 trials in 2000-2005 to 11,599 in 2021-2025, while the United States grew from 16,409 to 48,234. The absolute gap widened from 15,731 trials in 2000-2005 to 36,635 in 2021-2025 despite Africa's faster percentage growth rate. Hub concentration remained static with Egypt, South Africa, and Kenya dominating throughout all epochs. These findings demonstrate that the research divide is a structural equilibrium resistant to organic growth. Interpretation is limited by retrospective registration of older trials.
Question

In time-series analysis, has the absolute and proportional gap between African and high-income research volumes narrowed over fifteen years of clinical trial registration?

Dataset

This longitudinal audit tracked registration volumes across five epochs from 2000 to 2025 using ClinicalTrials.gov metadata for 23,873 African and 190,644 United States trials.

Method

Africa grew from 678 trials in 2000-2005 to 11,599 in 2021-2025, while the United States grew from 16,409 to 48,234.

Primary Result

The absolute gap widened from 15,731 trials in 2000-2005 to 36,635 in 2021-2025 despite Africa's faster percentage growth rate.

Robustness

Hub concentration remained static with Egypt, South Africa, and Kenya dominating throughout all epochs.

Interpretation

These findings demonstrate that the research divide is a structural equilibrium resistant to organic growth.

Boundary

Interpretation is limited by retrospective registration of older trials.