New Findings Reveal How Many Clinical Trial Countries Never Gain Access to the Medicines They Help Test

A major new study led by Yale researcher Jennifer Miller shines a bright light on a long-standing but often overlooked problem in global drug development: many countries that host clinical trials never actually receive the medicines they helped test. The research, published in JAMA Internal Medicine, gives one of the clearest, data-driven looks at how widespread this issue is and why it raises serious ethical concerns.

Between 2015 and 2018, pharmaceutical companies conducted clinical trials for 172 FDA-approved medicines across nearly 90 countries. These trials rely on thousands of volunteers, local hospitals, clinicians, and regulatory systems to generate the safety and effectiveness data needed for U.S. approval. But the study found that, even five years after FDA approval, only 24% of those medicines were officially authorized for sale in the countries where they were tested. In other words, three-quarters of the drugs never reached all the populations that contributed to their development.

The gaps grew even sharper when looking at country income levels. High-income countries had significantly better access to the medicines they helped test compared with upper-middle-income and lower-middle-income countries. Regions also differed sharply: places like Western Europe typically secured broad access, while regions such as Africa often saw very limited availability.

The findings underline a clear disconnect between participation and benefit. Clinical trial volunteers take on real risks, from side effects to time commitments, with the expectation that they are contributing not only to science but also to potential improvements in their own communities. Yet the data shows that in many countries, this expectation goes unfulfilled.

This issue relates directly to a core ethical concept known as distributive justice, which states that research participants—and by extension, their communities—should be able to benefit from the innovations they help create. This principle appears in major global ethics documents, including the World Medical Association’s Declaration of Helsinki and the CIOMS International Guidelines for Health-related Research. However, according to the researchers, these guidelines remain vague enough that companies can satisfy the letter of the rules without offering meaningful post-trial access.

The study emphasizes that accessibility here refers to something very basic: market authorization. This is the initial approval that allows a company to legally distribute a drug in a country. It does not measure whether patients can actually afford the treatment, whether supply chains exist to deliver it, or whether local health systems can support its use. So even the 24% figure likely overestimates real-world access.

This discrepancy raises an uncomfortable question: Why do pharmaceutical companies often conduct trials in a country but never pursue approval there afterward? Many factors may contribute—regulatory complexity, perceived limited profitability, infrastructure constraints, or strategic decisions to prioritize markets with faster or more lucrative returns. But none of these change the fact that people in lower-income countries frequently contribute to medical research without ever benefiting from the therapies that emerge.

To address part of this broader problem, Miller created the Good Pharma Scorecard, an index that evaluates pharmaceutical companies on ethical performance across multiple areas, including transparency and future plans for post-trial access. Half of the companies assessed have improved their performance within 30 days of seeing their rankings, suggesting that accountability and public visibility can drive change. The scorecard will soon expand to include more granular assessments of how companies handle post-trial access—a direct response to the issues highlighted in the new study.

The research team is also now studying what Miller refers to as bright spots. These are countries—such as Ethiopia and Uganda—that managed to obtain full access to the medicines they helped test. The goal is to analyze what went right in these cases and share lessons with other nations. The team plans to bring health ministers and clinical trial leaders from those bright-spot countries to Yale so they can discuss strategies with peers from countries that still face barriers.

The solution to this problem is not simple, and the researchers make that clear. Pharmaceutical companies would need to rethink access strategies. Countries would need stronger negotiating power and regulatory clarity. And outside influences—NGOs, media, patient organizations—must stay engaged to maintain pressure for equitable access. As Miller puts it, solving this will require all hands on deck because the “test it but don’t sell it” pattern has become too widespread to ignore.

Why Post-Trial Access Matters in the Bigger Picture

Beyond the specifics of this study, the topic connects with several larger issues in global health:

Expansion of multinational trials: Over the past 20 years, clinical trials have increasingly shifted beyond high-income countries. Companies often look to diverse patient populations, lower costs, and quicker recruitment. But this globalization makes post-trial fairness even more important.
Regulatory capacity gaps: Lower-income countries may lack the regulatory infrastructure needed to handle complex new drug applications quickly. Without adequate support, even eager governments struggle to get approvals done.
Affordability barriers: Even when market authorization is granted, brand-name medicines often launch at prices far out of reach for average citizens. So a country may officially have “access,” yet patients still cannot obtain the drug.
Trust in research: When communities repeatedly participate in studies without seeing benefits, it can erode trust. Hesitation to join clinical trials can slow down medical progress globally.

Understanding these broader issues helps put the study’s findings into perspective: this is not just about numbers but about the fairness and sustainability of the entire global clinical research system.

What Could Improve the Situation?

Experts have long discussed possible solutions, such as:

Mandating post-trial access plans as part of trial approval.
Harmonizing regulatory systems across regions to reduce the burden on companies.
Creating incentives—financial or reputational—to encourage companies to file for approval in all trial countries.
Strengthening national regulatory agencies in lower-income countries.
Increasing transparency, so communities know whether they are likely to receive the medicines they help test.

The Good Pharma Scorecard’s expansion into post-trial access measurements may be one of the most actionable steps in recent years because it uses public scoring to push industry behavior in a better direction.

Looking Ahead

The study’s clear data confirms what global health experts have been worried about for decades: hosting a clinical trial does not guarantee access to resulting medicines. And without structural reform, lower-income countries will continue shouldering research burdens without corresponding benefits.

But with research teams now identifying what works, with ethical scoring systems gaining traction, and with public awareness growing, there is real potential for change. The hope is that future clinical trial participants—no matter where they live—will not just contribute to medical research but will also share in its advances.

Research paper:
https://jamanetwork.com/journals/jamainternemedicine/fullarticle/10.1001/jamainternmed.2025.6060