TRACON Pharmaceuticals has terminated the Phase II ENVASARC trial for its sarcoma therapy, envafolimab, as the therapy is unlikely to show the level of efficacy required to support a biologics licence application (BLA).
The decision to scrap the Phase II ENVASARC trial (NCT04480502) was informed by a blinded independent central review analysis that showed that the therapy’s objective response rate (ORR) is 5% in the 82 patients evaluated for the analysis. This is lower than the 11% ORR needed to meet the trial’s primary endpoint and support a BLA.
Tracon has discontinued all its clinical development activities related to envafolimab and plans to reduce its cash burn. The company also plans to explore strategic alternatives, including a “merger, reverse merger, acquisition, other business combination, sales of assets, licensing or other strategic transactions”. The main asset that the company plans to leverage is its in-house product development platform. Tracon claims that the platform can offer cost and time savings while remaining independent of contract research organisations (CROs).
Following the news, the company stock was down by 30.6% at market close on 1 July, compared to market close on 28 June. Tracon’s market cap now stands at $2.97m.
Sarcomas are rare cancers that develop in the bones and soft tissues. Tracon investigated envafolimab as a treatment for two types of advanced or metastasised soft tissue sarcomas, undifferentiated pleomorphic sarcoma, or myxofibrosarcoma.
Envafolimab is a programmed death ligand 1 (PD-L1) targeting single-domain antibody. Tracon licenced North American rights to the therapy from China-based Jiangsu Alphamab Biopharmaceuticals and 3D Medicines in 2019.
In 2021, envafolimab was approved in China as a treatment for advanced microsatellite instability-high (MSI-H) or deficient mismatch repair (dMMR) advanced solid tumours, including advanced colorectal cancer. The therapy also received a breakthrough designation last year as a second-line treatment for non-MSI-H/non-dMMR advanced endometrial cancer, in China.
Other therapies in Tracon’s pipeline include YH001, a cytotoxic T lymphocyte-associated antigen 4 (CTLA-4)-targeting antibody being developed in partnership with China-based Eucure Biopharma, and TRC102 (methoxyamine), a small molecule inhibitor of the DNA base excision repair pathway.