iTeos Therapeutics to Wind Down Operations After TIGIT Therapy Setback

iTeos Therapeutics, a biotechnology company focused on developing cancer immunotherapies, has announced its decision to wind down operations and sell off remaining assets following disappointing clinical trial results for its anti-TIGIT therapy, belrestotug.

Strategic Review Leads to Closure

The company's strategic review, initiated just days ago, culminated in the decision to cease operations. iTeos expects to incur one-time costs between $21.8 million and $24.7 million for severance and employee termination expenses. As of the end of 2024, iTeos employed 173 full-time staff, with the majority involved in research and development.

Despite reporting $624.3 million in cash and investments during its first-quarter earnings report—enough to sustain operations through 2027—iTeos has opted for closure. The company will now focus on maximizing its remaining capital and shareholder value through potential sales of intellectual property and other assets, including the early-stage cancer therapy EOS-984 and a preclinical obesity program.

TIGIT Therapy Disappointment

The closure follows the termination of iTeos' partnership with pharmaceutical giant GSK for the development of belrestotug. The anti-TIGIT therapy, studied in combination with the PD-1 inhibitor Jemperli, failed to demonstrate clinically meaningful improvements in progression-free survival in non-small cell lung cancer (NSCLC) patients during the Phase II GALAXIES Lung-201 trial.

A parallel study, GALAXIES H&H-202, testing the same combination in head and neck squamous cell carcinoma, also yielded underwhelming results. The investigational regimen showed a "trend below the meaningful threshold" for objective response rate.

Broader Implications for TIGIT Development

iTeos' setback is not isolated in the TIGIT space. Several other pharmaceutical companies have encountered challenges in developing TIGIT-targeted therapies. BeOne Medicines (formerly BeiGene) recently abandoned its TIGIT therapy ociperlimab after an independent data monitoring panel found its Phase III NSCLC study unlikely to meet the primary endpoint of overall survival.

Industry giants such as Roche, Merck, and Bristol Myers Squibb have also faced obstacles in their TIGIT development programs, highlighting the complexities and risks associated with this emerging class of cancer immunotherapies.