Celleron Therapeutics announced the signing of a licensing agreement with Roche for worldwide rights for emactuzumab, a monoclonal antibody targeting the colony-stimulating factor 1 (CSF-1R). An Oxford spinout, Celleron has developed a proprietary platform based on epigenetic control and immune modulation. It aims to use the licensed asset for the treatment of diffuse tenosynovial giant cell tumor (TGCT), a rare disease where the tumor cells attract macrophages by over-expressing CSF-1R protein leading to inflammation. While the tumor generally remains benign, it can cause debilitating morbidity by damaging the joints and the surrounding tissues such as the tendons.
Roche initiated the clinical development for emactuzumab back in 2011 but shelved it in 2018, citing business decisions and emphasizing that there were no safety or efficacy concerns. Preliminary clinical data show that the drug was safe, well tolerated and was successful in eliciting a partial response to the drug in 68% of the patients. However, in a 2018 clinical study of the drug when combined with immune checkpoint inhibitor Tecentriq, was unable to demonstrate any favorable results over the use of Tecentriq administration alone.
TGCT is a debilitating condition that does not have any treatment options, surgery being the only resort, and even that doesn’t guarantee complete remission. The annual incidence of TGCT in the US is around 20,000 patients. In 2019, the US FDA approved Turalio (pexidartinib), developed by Daiichi Sanyo, for use in adult patients with symptomatic TGCT associated with severe morbidity or functional limitations and limited improvement with surgical interventions. Celleron has a lean portfolio of oncology drugs targeting conditions where there’s a significant unmet need for long-term disease control and the deal forged for emactuzumab for the treatment of rare cancer TGCT is aligned with its portfolio agenda.