Obsidian Therapeutics has reported positive top-line data from a Phase I clinical trial of its cell therapy candidate, OBX-115, to treat metastatic melanoma.
The first-in-human trial that is underway is designed to analyse the efficacy and safety of OBX-115 in patients with melanoma that has relapsed and/or is refractory to previous treatment with an immune checkpoint inhibitor (ICI).
An objective response rate (ORR) of 50%, with 33% complete responses, was reported at a median follow-up period of 18 weeks.
Disease control rate in the trial was 100%, with responses intensifying over time.
No dose-limiting toxicities were reported in the trial, and the treatment-emergent adverse event profile was in line with that of lymphodepletion.
A tumour-infiltrating lymphocyte (TIL) cell therapy with pharmacologically regulatable membrane-bound IL15, OBX-115 has the potential to become a therapeutic option for melanoma and other solid tumours.
Obsidian Therapeutics chief development officer Parameswaran Hari said: “The OBX-115 data show its potential to be a meaningful advancement in the treatment of metastatic melanoma and TIL cell therapy.
“These initial topline results support the promise for OBX-115 to drive responses in this heavily pre-treated patient population and facilitate the expansion of TIL cell therapy in melanoma to a broad group of patients, without the need for IL2 [interleukin-2].”
In another development, the company enrolled the first subject in a multicentre Phase I/II clinical trial of OBX-115 in patients with advanced or metastatic melanoma who are resistant to ICI therapy.
Obsidian Therapeutics CEO Madan Jagasia said: “These positive results underscore the potential for OBX-115 TIL cell therapy to offer patients with metastatic melanoma a differentiated TIL therapy, without the need for IL2.
“Furthermore, the emerging profile of OBX-115 indicates it will allow expansion of TIL cell therapy into a broad patient population, including those who may not be able to tolerate IL2 or choose not to receive it.”
