Abstract LB-B006: A Phase II chemo/immunotherapy study using metronomic gemcitabine, doxorubicin, docetaxel and nivolumab for advanced angiosarcoma (NCT04535713): An interim analysis

Abstract Background: Advanced angiosarcoma is a rare and aggressive sarcoma which is most often fatal, with a median progression free survival of 4-6 months on standard therapy. Therefore, innovative treatment regimens are urgently needed. Methods: Endpoints: Primary: Progression Free Survival; Secondary: Best overall response; Overall Survival; Incidence and severity of adverse events. Eligibility: > 18 years, confirmed diagnosis of advanced angiosarcoma, acceptable hematologic and organ function. Treatment Schedule: Gemcitabine (600 mg/m2; max:1000 mg), doxorubicin (18 mg/m2; max: 32 mg), docetaxel (25 mg/m2; max:42 mg) on Days 1 and 8, and nivolumab (240 mg) on Day 1 of a 3-week cycle. Results: Median prior regimens = 1 (range 0-9). Efficacy: 7 of 9 patients who completed at least 2 treatment cycles and follow-up imaging (modified ITT population) were evaluated for: Median PFS: 9.4 months (95% CI: 8.224 to 9.441; 7 events, 0 censored); Best response: Confirmed 1 CR, 3 PR, 3 SD; ORR = 57%; DCR = 100%. Nine patients who received at least one dose of each chemotherapy agent (ITT population) were evaluated for: Median OS: 28.4 months (95% CI: 0.724 to 31.217; 5 events, 4 censored). Safety: 8 of 9 (89%) patients experienced a ≥ Grade 3 TRAE: leukopenia (n=6), thrombocytopenia (n=4), neutropenia (n=5), anemia (n=2), lymphopenia (n=2), fatigue (n=1), dec. LVEF (n=1), periorbital edema (n=1), limb edema (n=1) and worsening hypothyroidism (n=1). There were no Grade 5 nor unexpected adverse events. Conclusion: This metronomic chemo/immunotherapy regimen may be a synergistic and effective therapy for advanced angiosarcoma with manageable toxicity. Citation Format: Oliver Davidorf, Sarah Lande, Samantha Jeffrey, Anmol Dia Agarwal, Piya Mann, Allyssa Lingad, Alex Borsada, YuJeong Yoon, Mihir Chawla, Halu Kauffman, Michael Siriprabrydhi, Stephanie Melchor, Neal Chawla, Ania Moradkhani, Ted Kim, Victoria Chua-Alcala, Sant Chawla, Erlinda Gordon. A Phase II chemo/immunotherapy study using metronomic gemcitabine, doxorubicin, docetaxel and nivolumab for advanced angiosarcoma (NCT04535713): An interim analysis [abstract]. In: Proceedings of the AACR Immuno-Oncology Conference (AACR IO): Discovery and Innovation in Cancer Immunology: Revolutionizing Treatment through Immunotherapy; 2026 Feb 18-21; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Immunol Res 2026;14(2 Suppl):Abstract nr LB-B006.