Sesen Bio Inc

Sesen Bio was a Cambridge, Massachusetts company whose lead drug, Vicineum (VB4-845), was in development for BCG-unresponsive non-muscle invasive bladder cancer. After an FDA complete response letter in August 2021, Sesen paused US development of Vicineum in July 2022, citing the time and cost of another Phase 3 trial. Sesen completed its merger with Carisma Therapeutics on March 7, 2023, and the combined company took the name Carisma Therapeutics. BioSpace and Fierce Biotech reported in April 2025 that Carisma was winding down operations and keeping only 6 staff. Sesen Bio has no active trials or approved drugs.

Sesen Bio Inc is a diversified pharmaceutical company headquartered in Cambridge, United States, founded in 2010. While it operates across multiple therapeutic areas, it maintains a significant rare disease portfolio with 0 active rare disease programs. Many of its rare disease treatments hold orphan drug designations from the FDA.

The clinical trials section on this page shows active and recruiting rare disease trials sponsored by Sesen Bio Inc, pulled live from ClinicalTrials.gov. Each trial card includes the study phase, recruitment status, conditions being studied, number of trial sites, and a direct link to the full study record. You can also explore individual disease pages to see trials from all sponsors for a specific condition.

To explore enrollment, find a recruiting trial in the clinical trials list on this page and click "View full study" to see the full ClinicalTrials.gov record, which includes eligibility criteria, study locations, and contact information for each trial site. Your doctor can also help determine if a specific trial is appropriate for your condition. Not all trials are open at every location, so check the site list for one near you.

Sesen Bio Inc was founded in 2010 and is headquartered in Cambridge, United States. The company has been active for 16 years. It is a subsidiary of Carisma Therapeutics.