Celleron Therapeutics Acquires Global Rights to Roche’s Investigational CSF-1R Antibody Emactuzumab for Tenosynovial Giant Cell Tumor

Compiled by Keke

On August 12, Celleron Therapeoutics announced that it had entered into a licensing agreement with Roche, securing exclusive global rights to the clinical development, manufacturing, and commercialization of Roche’s investigational cancer drug emactuzumab. The transition is expected to be fully completed by the end of 2020. The two companies did not disclose the financial terms of the transaction.

According to reports, emactuzumab (RG7155) is an investigational monoclonal IgG1 antibody designed to target and eliminate tumor-associated macrophages (TAMs) within tumor tissues. TAMs are abundant components of the tumor microenvironment in many cancer types, supporting tumorigenesis by suppressing local immune responses and promoting tumor cell growth. Emactuzumab specifically targets TAMs by binding to the colony-stimulating factor-1 receptor (CSF-1R) on the cell surface and blocking its activation via the macrophage colony-stimulating factor CSF-1. Treatment with this drug has been shown to significantly reduce CSF-1-dependent macrophages in tumors of patients with tenosynovial giant cell tumor (TGCT) and other cancers.

Tenosynovial giant cell tumor (TGCT) is a rare disease characterized by proliferation of synovial tissue in joints and tendon sheaths, while diffuse-type TGCT is marked by macrophage proliferation within the synovium. Although this condition rarely metastasizes, it is locally aggressive and can be debilitating. The standard treatment is surgery, but high recurrence rates are common, and patients’ quality of life is often compromised by tumor-related symptoms and postoperative sequelae. In August 2019, the U.S. FDA approved Daiichi Sankyo’s Turalio (pexidartinib) for the treatment of adult patients with TGCT; however, its use is restricted to cases where surgery is not feasible, and it carries a boxed warning for hepatotoxicity.

In 2018, clinical studies evaluating emactuzumab in combination with the checkpoint inhibitor Tecentriq demonstrated that the combination therapy yielded less-than-expected outcomes in solid tumors compared to Tecentriq monotherapy. In the same year, Roche prepared to initiate another combination trial in patients with lymphoma but withdrew from the study before the enrollment of the first subject, thereby shelving the asset. At the time, Roche stated that there were no safety or efficacy concerns, and this decision marked the end of Roche’s interest in developing the asset.

However, the current licensing agreement indicates that Celleron is highly optimistic about the future of emactuzumab. Celleron plans to develop the drug for the treatment of diffuse tenosynovial giant cell tumor (TGCT). Previous studies conducted by Roche and its subsidiary Genentech demonstrated that emactuzumab exhibited highly encouraging efficacy against this specific target. In these studies, 86% (24 patients) of TGCT patients treated with emactuzumab responded to the drug, and 68% of patients achieved a partial response within six weeks of initiating treatment. The study population included patients who had previously tried imatinib or nilotinib but failed to achieve durable efficacy.

In addition to the assets licensed from Roche, Celleron established a global licensing partnership with AstraZeneca in 2009 for AZD9468 (now known as CXD101), a dual-mechanism histone deacetylase (HDAC) inhibitor. Celleron is leveraging its CancerNav predictive biomarker platform to identify tumors most likely to respond to the drug, evaluate the efficacy of CXD101 both as a monotherapy and in combination with checkpoint inhibitors, and has initiated new clinical trials in China. Furthermore, another asset of the company, the topoisomerase inhibitor CXD201, has entered Phase II clinical studies for the treatment of patients with colorectal cancer.

Celleron’s R&D Pipeline and Clinical Progress

Reference Source:

1、Celleron Therapeutics Gains Worldwide Rights to Shelved Roche Drug

2、Celleron Therapeutics enters into a license agreement with Roche to improve the lives of patients living with tenosynovial giant cell tumour