Instil Bio takes the ax to its lead asset, cutting 60% of its staff in the process

Instil Bio is calling it quits on its lead tumor-infiltrating lymphocyte therapy and four corresponding programs, a major overhaul of the company’s priorities that’s resulting in 60% of its staff getting laid off. 

Calling it a tough pill to swallow is an understatement. It would be more accurate to say the moves announced Thursday are an entirely new corporate treatment regimen that the company is undertaking. With ITIL-168 now shelved, the company is focused on its CoStAR platform, which includes one phase 1-stage asset, ITIL-306. But the pipeline contraction means a majority of staff are being asked to depart. The company says the decision to ax ITIL-168 came after assessing the viability of restarting its DELTA-1 trial in patients with advanced melanoma. Evidently, the company felt its best commercial prospects lay elsewhere. 

“Although it was a difficult decision to discontinue the development of ITIL-168, this decision provides us the opportunity to accelerate the development of CoStAR and other novel technologies to enhance TIL therapies for patients,” said CEO Bronson Crouch.

Nothing can be accelerated, however, until dosing resumes in the ITIL-306 trial. The company voluntarily paused enrollment across its trials in late October after acknowledging that ITIL-168 was being successfully manufactured at lower rates, limiting supply for clinical trials. Instil said the pause was not the result of any clinical hold placed on it by regulators. In its third quarter earnings report, Instil said that an investigation identified contamination in the cell media as the central source of the problem. 

The company also said no issues with ITIL-306 manufacturing were observed, but that it was being included in the pause as part of its overall review. Instil hopes to have an update on the manufacturing assessment early in the first quarter of 2023. In Thursday’s announcement, Crouch said the company was “excited” to resume dosing and that an initial readout of the ITIL-306 trial would be coming sometime in 2023. 

The CoStAR platform now taking centerstage looks to add firepower to the body’s T-cells by adding synthetic costimulatory signals in the tumor microenvironment. The phase 1 trial is assessing ITIL-306 in patients with non-small cell lung cancer, renal cell carcinoma and ovarian cancer.