IPM Take
This is not only a diversity problem. It is an evidence-quality problem. If pivotal trials supporting oncology approvals underrepresent the people likely to receive treatment in routine care, regulators, payers and clinicians are making decisions from an incomplete evidence base. For precision oncology, that weakness becomes sharper because eligibility is already narrowed by biomarkers, age, comorbidity, referral patterns and trial access.
Executive Summary
A 2026 Frontiers in Oncology study analysed 329 pivotal trials supporting FDA oncology drug approvals from January 2018 to November 2024, covering more than 164,000 participants. The authors found persistent underrepresentation of women, Black participants, Hispanic participants and older adults. Pooled enrollment incidence ratios were 0.83 for women, 0.26 for Black participants, 0.50 for Hispanic participants and 0.86 for older adults, where values below 1 indicate underrepresentation. The findings reinforce why representative enrolment is becoming central to both equity and evidence quality in cancer care.
Why it matters
- Regulators: Need to keep trial representativeness visible when assessing whether approval evidence applies to real-world patients.
- Industry / innovation partners: Should design recruitment, site selection and enrolment plans that reflect the population expected to use the treatment.
- Patients / advocates: Can use these data to push for trial access that includes older adults and historically underrepresented communities.
Previously, oncology trial diversity was often treated as an ethical inclusion issue. This study makes it harder to separate equity from scientific validity.
What changed is the scale and regulatory relevance of the analysis. These were not peripheral studies. They were pivotal trials supporting FDA oncology approvals, meaning they helped form the evidence base behind treatments entering routine care. The findings suggest that even after years of policy attention, trial populations still do not fully reflect the patients who may receive these therapies after approval.
The affected group is broad: patients whose age, sex, race or ethnicity is not adequately reflected in the studies behind approved treatments. For precision oncology, the access problem is even more complex because biomarker testing, specialist referral and trial availability can further narrow who reaches the evidence-generating pathway.
The implication is simple but uncomfortable. Precision oncology cannot be fully credible as a population-level strategy if its evidence base is precise but not representative. Trial diversity is not a side box. It is part of whether personalised medicine can be trusted across real health systems.
