The U.S. Food and Drug Administration (FDA) has given preliminary support to Dei BioPharma Ltd.'s plans to develop a lower-cost version of one of the world's leading cancer immunotherapy medicines.
In a letter dated July 14, the FDA provided detailed preliminary comments on PSI-033, the company's proposed biosimilar to Yervoy (ipilimumab), a cancer immunotherapy marketed by Bristol Myers Squibb. The feedback comes ahead of a scheduled meeting between Dei BioPharma and the FDA on July 22.
The meeting will be led by Dr. Matthias Magoola, founder and chief executive of Dei BioPharma, the Ugandan biotechnology company developing a major pharmaceutical manufacturing facility aimed at producing affordable biological medicines and vaccines for local, regional and international markets.
According to documents reviewed, the engagement falls under the FDA's Biosimilar Development (BPD) Type 2b programme, which provides companies with targeted scientific advice on issues such as analytical strategy, manufacturing controls and clinical study design.
In a statement, Dei BioPharma said the FDA indicated that several key elements of the development programme are achievable. These include the proposed drug formulation, stability-testing plan, viral-clearance strategy and a manufacturing approach based on three consecutive commercial-scale batches produced at the 500-litre scale.
The FDA also indicated that animal studies may not be necessary if analytical data demonstrate a high degree of similarity to Yervoy. Similarly, the agency said a separate clinical efficacy study could potentially be waived if analytical assessments and pharmacokinetic studies show no clinically meaningful differences between the biosimilar and the reference product.
Such an approach could significantly shorten the development timeline, although the company would need to justify it in any future regulatory submission.
Because ipilimumab, the active ingredient in Yervoy, is associated with serious immune-related adverse effects, the FDA advised that pharmacokinetic studies should not be conducted in healthy volunteers. Instead, the agency recommended collecting sufficient safety data in patients to adequately assess those risks across treatment groups.
"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," said Dr. Magoola. "We intend to address these recommendations with urgency and scientific rigor."
The global market for cancer immunotherapies continues to expand. Bristol Myers Squibb reported approximately US$2.9 billion in worldwide Yervoy sales in 2025, representing a 15% increase from the previous year. According to the FDA, there are currently no approved biosimilars for ipilimumab in the United States, positioning Dei BioPharma among the companies with the potential to become first to market, subject to regulatory approval and competition.
Yervoy is only one of several products in the company's biosimilar pipeline.
Dei BioPharma said it is also developing a proposed biosimilar to Opdivo (nivolumab), another Bristol Myers Squibb cancer immunotherapy that generated approximately US$10 billion in global sales in 2025.
"Our engagement with the FDA extends beyond PSI-033," Dr. Magoola said. "This portfolio approach is central to our objective of building globally competitive biologics development and manufacturing capacity in Uganda while expanding access to essential medicines."
He added:
"Our dream of making biological medicines available and affordable to more than 80% of countries that currently cannot afford these treatments is coming to fruition."
The company said it aims to submit its U.S. regulatory application for PSI-033 within approximately nine months, subject to completing the remaining analytical and clinical studies and maintaining alignment with FDA requirements.
Founded in 2014, Dei BioPharma is a Ugandan biotechnology company focused on developing biologic medicines, biosimilars and vaccines while building pharmaceutical research and manufacturing capacity across Africa.
Its manufacturing complex in Matugga is among the largest pharmaceutical production facilities on the continent. The flagship plant was inaugurated in July 2021 by President Yoweri Museveni and Kenyan President William Ruto.
The more than 250-acre facility is designed to manufacture medicines across multiple therapeutic areas, including treatments for malaria, HIV/AIDS, cancer, diabetes, monoclonal antibodies and mRNA-based therapeutics.
In May 2024, Uganda's National Drug Authority (NDA) licensed the company to manufacture medicines, including non-beta-lactam tablets and hard gelatin capsules.
Dei BioPharma says it has filed more than 100 patent applications with the U.S. Patent and Trademark Office and is preparing to manufacture mRNA vaccines to international standards. The company projects that its operations will create tens of thousands of jobs while reducing Uganda's dependence on imported medicines.
Senior government officials, including those from the Ministries of Finance and Health, have described the facility as a strategic investment capable of strengthening Uganda's pharmaceutical sector, lowering medicine import costs and supporting long-term economic growth.
