Regeneron Enters $275M Gene Editing Alliance With Tessera Therapeutics

Regeneron Pharmaceuticals has taken a major step deeper into genetic medicine with a new collaboration with Tessera Therapeutics worth up to $275 million. The partnership focuses on developing TSRA-196, an experimental in vivo (inside the body) gene-editing treatment for alpha-1 antitrypsin deficiency (AATD), a hereditary disorder that prevents the body from making a key protective protein called alpha-1 antitrypsin. When this protein is missing or faulty, the lungs and, in some cases, the liver slowly accumulate damage over time. Current treatments only manage symptoms. None of them fixes the root cause of the disease. This deal signals Regeneron’s belief that gene editing is close to solving problems that once seemed impossible.

The structure of the agreement highlights how seriously both companies are taking this program. Regeneron is giving Tessera $150 million upfront, a mix of cash and equity investment, and Tessera could receive up to $125 million more when certain development milestones are met. Beyond the payments, the companies will split all development costs and future profits equally, a rare 50-50 global arrangement that typically appears only when both sides feel the technology could define a new category of medicines. Tessera will lead the early work, including filing an Investigational New Drug (IND) application with the United States Food and Drug Administration and running the first-in-human clinical trial, which they expect to begin after regulatory clearance. After that, Regeneron will take over global development and commercialization.

At the center of all this is TSRA-196, Tessera’s leading “Gene Writing” candidate. Instead of traditional gene therapies that add a new copy of a gene, this approach is designed to correct the faulty SERPINA1 gene directly, restoring the body’s natural ability to produce the alpha-1 antitrypsin protein. It is intended as a one-time treatment, not a lifelong regimen. Early preclinical studies in non-human primates showed encouraging results, strong and accurate editing of the target gene, very few unintended genetic changes, no detectable effects on reproductive cells, and an overall favorable safety profile. These results were shared this year at the American Society of Gene and Cell Therapy (ASGCT) annual conference and have drawn attention because they suggest the therapy could eventually offer a real, permanent fix rather than symptom management.

This collaboration is also part of a much broader strategy. Regeneron has been steadily building one of the most comprehensive portfolios of genetic medicines in the industry. It is advancing DB-OTO, a gene therapy for congenital hearing loss, which recently demonstrated meaningful hearing improvements in early-stage trials. In 2024, the company also partnered with Mammoth Biosciences to expand its access to next-generation gene-editing tools, and it continues its long-standing CRISPR program with Intellia Therapeutics. With the addition of Tessera’s gene-writing technology, Regeneron is positioning itself to compete at the center of the next major wave in biotechnology, medicines that don’t just treat disease but aim to repair the underlying genetic errors themselves.