The cancers killing poor aren't being studied. WHO flags global trial gaps

Published in Nature Medicine, the WHO review shows most clinical trials are concentrated in rich countries and ignore the deadliest cancers in low-income regions

Cancer research is booming worldwide, but it is leaving the most vulnerable populations behind. A new World Health Organization (WHO) analysis reveals that most cancer clinical trials are concentrated in wealthy nations, while 63 countries have none at all.

 

WHO’s review, The WHO global landscape of cancer clinical trials, published in Nature Medicine, found that the cancers responsible for the highest number of deaths in low- and middle-income regions—like liver, cervical, stomach and pancreatic cancers—are among the least studied.

What did the WHO study find about cancer clinical trials worldwide?

Between 1999 and 2022, nearly 89,000 interventional cancer trials were registered globally. While this marks impressive scientific progress, WHO researchers found that 70 per cent of all trials were hosted in high-income countries. In fact, the United States, China, Japan, Germany, France, the UK and Italy together dominate the trial landscape. Shockingly, 63 countries have no registered oncology trials at all, creating what experts call “trial deserts”.

 

Which cancers are being neglected in global research?

According to the WHO, cancers like breast, lung, lymphoma and leukaemia attract the most trials, even though survival rates for many of these have improved in wealthy nations. Meanwhile, liver, cervical, pancreatic and stomach cancers—major killers in Africa and Southeast Asia—are consistently underrepresented. This means the cancers causing the most deaths in poorer countries often have the least research dedicated to them.

Why does trial location matter for patients?

According to the UN health body, trials shape the future of cancer care by testing new drugs, therapies and technologies. If studies are concentrated in rich countries, patients in low- and middle-income regions miss out on early access to innovative treatments. Even more concerning, trial results may not reflect diverse populations, raising questions about how well new treatments work in different genetic, environmental and healthcare settings.

Glaring demographic gaps

According to the study, only 3.3 per cent of trials enrolled children under 14, despite the unique biology of childhood cancers. For older adults, who represent the majority of cancer patients, just 28 per cent of trials explicitly included people over 60. This underrepresentation raises concerns about whether treatments being tested are truly safe and effective across age groups.

Most trials focused only on novel drugs: WHO

WHO’s analysis shows that 61 per cent of all trials are drug-related. In comparison, only about 3 per cent cover radiotherapy, 3 per cent surgery, and 1 per cent diagnostics. This drug-heavy bias, often influenced by commercial funding, risks sidelining other vital aspects of cancer care like early detection, supportive care and palliative treatment.

How collaborative is cancer research globally?

The study shows that as much as 85 per cent of trials are confined to a single country. Only 15 per cent are multinational, and just 3 per cent of active recruiting trials involve collaboration between high-income and low-income countries. Limited cross-border partnerships mean missed opportunities to share data, reduce costs, and make findings more widely applicable.

What solutions does WHO recommend?

The study does not just highlight problems; it also offers a roadmap for change. WHO calls for:

• Building trial capacity in low- and middle-income countries with funding, infrastructure and trained researchers
• Aligning research with disease burden, ensuring high-mortality cancers like liver and cervical cancer get priority
• Investing beyond drugs, in diagnostics, surgery and radiotherapy
• Encouraging multinational collaborations, especially “south–south” partnerships between low-resource countries
• Making trials more inclusive, with adequate sample sizes and representation across age groups
• Improving transparency by enforcing full and timely trial registration

Cancer already claims nearly 10 million lives a year worldwide, and WHO predicts 35 million new cases annually by 2050, which is a 77 per cent rise from 2022. With over 70 per cent of deaths expected in low- and middle-income countries, aligning cancer research with global needs is not just a scientific priority but a moral imperative, the study has stressed.