The United States Food and Drug Administration (FDA) has provided preliminary regulatory guidance to Dei BioPharma Ltd. as the Ugandan biotechnology company advances plans to develop a lower-cost version of a widely used cancer immunotherapy drug.
The FDA issued detailed comments on PSI-033, Dei BioPharma’s proposed biosimilar to Yervoy (ipilimumab), a cancer treatment manufactured by global pharmaceutical company Bristol Myers Squibb.
The feedback, contained in a letter dated July 14, was issued ahead of a scheduled meeting between Dei BioPharma and the FDA on July 22.
The engagement falls under the FDA’s Biosimilar Development Type 2b pathway, which provides companies with targeted scientific guidance on key areas, including analytical strategies, manufacturing processes, quality controls and clinical study designs.
The FDA’s feedback indicated that several aspects of Dei BioPharma’s development programme are achievable, including the proposed formulation, stability testing plan, viral clearance studies and manufacturing strategy based on three consecutive commercial-scale batches produced at the 500-litre scale.
According to Dei BioPharma, the FDA also indicated that an animal study may not be required if analytical evidence demonstrates a high level of similarity between PSI-033 and Yervoy.
The agency further suggested that a separate clinical efficacy trial may not be necessary if analytical studies and pharmacokinetic data demonstrate no clinically meaningful differences between the biosimilar and the reference product. However, the company would be required to justify such an approach in any future regulatory submission.
Because ipilimumab, the active ingredient in Yervoy, is associated with serious immune-related side effects, the FDA advised that pharmacokinetic studies should not be conducted among healthy volunteers and should instead collect sufficient safety data to assess risks among treatment groups.
Speaking after receiving the FDA guidance, Dr. Matthias Magoola, founder of Dei BioPharma, said the feedback provides a clear direction for advancing the product towards regulatory submission.
“The FDA’s detailed preliminary comments give us a clear, product-specific roadmap for strengthening the analytical package, completing the clinical pharmacology programme and preparing PSI-033 for a future U.S. licensing application. We intend to address these recommendations with urgency and scientific rigor.”
The global demand for cancer immunotherapies continues to rise. Bristol Myers Squibb reported approximately US$2.9 billion in worldwide Yervoy sales in 2025, representing a 15 percent increase from the previous year.
Currently, the FDA lists no approved ipilimumab biosimilar, meaning Dei BioPharma could become among the first companies seeking approval for such a product in the United States, subject to successful development, regulatory review and competition.
Beyond PSI-033, Dei BioPharma is also developing additional biosimilar medicines, including a proposed version of Opdivo (nivolumab), another Bristol Myers Squibb cancer treatment that generated about US$10 billion in sales in 2025.
“Our engagement with FDA extends beyond PSI-033. This portfolio approach is central to our objective of building globally competitive biologics development and manufacturing capacity in Uganda and expanding access to important medicines,” Dr. Magoola said.
He added that the company’s long-term ambition is to make biological medicines more accessible to countries that currently struggle to afford advanced treatments.
“Our dream of making biological drugs available and affordable to more than 80 percent of countries that cannot afford these medicines is coming to fruition.”
Dei BioPharma said it plans to submit its PSI-033 application within approximately nine months, subject to completion of remaining analytical and clinical work and continued alignment with FDA requirements.
Established in 2014, Dei BioPharma is a Ugandan biotechnology company focused on developing biologic medicines, biosimilars and vaccines while building pharmaceutical research and manufacturing capacity in Africa.
The company operates a major manufacturing complex in Matugga, one of the continent’s largest pharmaceutical facilities. The plant was inaugurated in July 2021 by President Yoweri Museveni and Kenyan President William Ruto.
Located on more than 250 acres, the facility is designed to manufacture medicines across multiple therapeutic areas, including treatments for malaria, HIV, cancer, insulin products, monoclonal antibodies and mRNA-based therapeutics.
In May 2024, Uganda’s National Drug Authority (NDA) licensed Dei BioPharma to begin manufacturing medicines, including non-beta-lactam tablets and hard gelatin capsules.
The company says it holds more than 100 patents filed with the U.S. Patent and Trademark Office and is preparing to manufacture mRNA vaccines to international standards.
Government officials have identified the facility as a strategic investment that could strengthen Uganda’s pharmaceutical industry, reduce dependence on imported medicines and create thousands of employment opportunities.
