Key numbers at a glance
- <56% of clinical trials reach their target enrollment.
- 43% pooled dropout rate reported across chronic disease trials.
- ~20% of trials finish on time, with a 12.2-month median delay.
- 1.1% of global clinical trials are conducted in Africa.
- African site networks report >80% consent and 85%–96% retention, highlighting strong recruitment and participant engagement.
The conduct of controlled clinical trials in traditional settings is faced with many challenges often resulting in important delays in the execution of studies. In most geographic settings, there is a limited pool of eligible patients because of small catchment areas and competition for participation in other studies. Many studies are faced with slow recruitment because eligibility criteria have increased and trials become more complex. In a metanalysis of clinical trials in the UK less than 56% of clinical trials reached the target sample size.1 Another metanalysis of clinical trials in chronic disease found a pooled dropout rate of 43%.2 And lastly, a metanalysis of 2,542 randomized clinical trials showed that around one out of five studies completes within the planned timeframe, and that the median delay in completion is 12.2 months.3
Africa remains underrepresented in global clinical research
According to estimates, only 1.1% of clinical trials are being conducted in Africa.4 This lack of interest in considering this region for the roll-out of clinical trials is rooted in lack of knowledge and misconceptions about what can be done.
In the past two decades, funding by development agencies has resulted in the building of important capacity and capabilities in the execution of controlled clinical trials, predominantly focused on infectious diseases, including HIV/AIDS, tuberculosis, COVID-19, and Human Papilloma Virus infection. The capacity covers a wide-range of drug and vaccine trials, studies on the accuracy of diagnostic tests, and efficacy and effectiveness of medical devices. A comprehensive database has identified around 5,000 potential clinical research sites throughout Africa.5
Declining donor funding leaves untapped research capacity
The funding of donor-funded clinical research activities in sub-Saharan Africa has recently declined because of the discontinuation of development aid through several bilateral and multilateral programs. This frees up a large, untapped potential of highly qualified medical professionals trained in Good Clinical Practices (GCP) and working according to Standard Operating Procedures (SOPs) and policies, and infrastructure related to networks of dedicated clinical research sites, laboratories, and medical equipment. The catchment area of the clinical research sites includes many millions of patients representing an extensive pool of potential study participants.
Rising burden of non-communicable diseases expands trial potential
Sub-Saharan Africa offers an excellent opportunity in conducting clinical research in non-communicable diseases due to demographic shifts to ageing populations, increasing adoption of unhealthy Western lifestyles (smoking, substance abuse, fast food consumption, lack of physical exercise), genetic predisposition, and environmental factors (biomass smoke exposure):
- The pooled prevalence of Chronic Obstructive Pulmonary Disease (COPD) in sub-Saharan Africa is 8% with a variance between 1.7 and 24.8% depending on geographical and socio-demographic factors.6
- More than 30% of adults have high blood pressure, but most cases are undiagnosed and of those only a small portion are treated with antihypertensive medication.7 As a consequence, the incidence of different manifestations of ischemic heart disease is increasing.
- The age-related prevalence of diabetes is currently relatively low with 5% or 25 million adults living with type 2 diabetes but is expected to increase in the next 25 years to 60 million, while overweight and obesity-related pre-diabetes is currently estimated as 95 million reaching 223 million by 2050.8
- The incidence of breast cancer in sub-Saharan Africa is reported to be close to 200,000 annually, roughly 8% of worldwide incidence. The cancer-associated mortality is disproportionally high at 15%, reflecting the lack of treatment access.9
Genetic diversity strengthens oncology and precision medicine research
The population of Africa has the greatest diversity of genetic variation in the world. Our species arose in Africa about 150,000 years ago, while in the last 30 to 40,000 years small groups of humans with limited genetic variation migrated to, and settled in, the rest of the world, resulting in declines of genetic diversity in the ancestors of Europeans, Asians, and others.10 A genetically diverse study population in clinical trials is of critical importance to understand the efficacy and effectiveness of study medication in oncology trials.