SynOx Therapeutics Reports Positive Phase 3 Results for Emactuzumab in Tenosynovial Giant Cell Tumor
核心洞察
SynOx Therapeutics (搜索) announced positive topline results from the Phase 3 TANGENT study, with emactuzumab meeting primary and secondary endpoints with high statistical significance versus placebo at 6 months.
The CSF-1R (搜索) inhibitor demonstrated rapid onset and significant functional improvements in patients with TGCT (搜索) using a short-course regimen of five doses over 8 weeks.
Emactuzumab showed sustained and durable clinical benefits with a manageable safety profile, potentially addressing limitations of chronic oral treatment approaches.
SynOx Therapeutics (搜索) announced positive topline results from the pivotal Phase 3 TANGENT study of emactuzumab in adult patients with tenosynovial giant cell tumor (搜索) (TGCT (搜索)), marking a potential breakthrough in treating this rare but debilitating condition. The study met its primary and secondary endpoints with high statistical significance versus placebo at 6 months, including objective response rate by RECIST V1.1 and Tumor Volume Score, along with clinically meaningful improvements in patient-relevant functional measures.
Study Design and Results
The TANGENT clinical trial (NCT05417789) was a global, multicenter, randomized, double-blind, placebo-controlled Phase 3 trial evaluating emactuzumab's efficacy and safety in TGCT (搜索) patients. Patients in the treatment arm received 1,000 mg emactuzumab every two weeks for a total of five doses over an 8-week period, representing a short-course treatment approach designed to avoid chronic treatment burden.
Results demonstrated clinically meaningful and statistically significant benefits across primary and key secondary endpoints, including measures of tumor volume reduction and patient-reported functional outcomes such as PROMIS-PF, physical function, pain, range of motion, and stiffness. Importantly, these benefits were achieved rapidly within the short-course treatment cycle and showed durability across clinically relevant patient segments.
Safety Profile and Clinical Significance
Emactuzumab demonstrated a manageable safety profile in TANGENT, consistent with prior clinical experience. In a patient population with a chronic, debilitating but non-lethal disease, tolerability remains an important consideration, particularly when compared with long-term treatment approaches.
"The TANGENT results represent an important step in advancing a potential next-generation treatment for patients with TGCT (搜索)," said Dr. Ray Barlow, CEO of SynOx Therapeutics (搜索). "Emactuzumab's combination of rapid onset, response rate, meaningful functional improvement, and a defined short-course regimen positions it as a potential alternative to chronic therapy."
Addressing Unmet Medical Need
TGCT (搜索) is a rare, non-malignant but locally aggressive and destructive tumor affecting the synovium, tendon sheaths, and bursa membranes, primarily located in knee, hip, and ankle joints. The disease is estimated to affect approximately 200,000 patients in the U.S. and 179,000 patients in the EU4 +UK, with an estimated incidence of approximately 50 per million.
Current treatment options include surgery and oral systemic therapies, but both have significant limitations. Surgery carries risks of complications and severe morbidity, with high recurrence rates of 17% for localized disease and 72% for diffuse disease. Approved oral TKI therapies require long-term chronic administration.
Dr. Jean-Yves Blay, Principal Investigator, commented: "Emactuzumab is the only short course treatment option in late-stage development for patients suffering with TGCT (搜索). These Phase 3 data provide compelling evidence of tumor response, a manageable safety profile, and most importantly for patients, of significant durable functional and quality of life benefits that allow patients struggling with TGCT to move forward with their lives, without continuous therapy."
Mechanism of Action and Development Status
Emactuzumab is a next-generation monoclonal antibody and high-affinity CSF1-R (搜索) inhibitor designed to block receptor activation, deplete tumor-promoting macrophages, and reduce inflammation in the tumor microenvironment. The drug has received Fast Track Designation from the U.S. Food and Drug Administration and Orphan Medicinal Product designation from the European Medicines Agency for TGCT (搜索) treatment.
Regulatory Timeline
Based on these data, SynOx plans to submit a Biologics License Application to the U.S. Food and Drug Administration for emactuzumab in TGCT (搜索) in the second half of 2026, with a Marketing Authorization Application in the EU to follow. The company continues to follow patients enrolled in the TANGENT study to further characterize durability of response and the potential role of retreatment.
SynOx intends to present full data from the TANGENT trial at an upcoming medical meeting and in a peer-reviewed publication. The study includes an 18-month follow-up phase during which patients demonstrating disease progression may receive open-label emactuzumab.