Phase II trial, multicenter, first line paclitaxel-avelumab treatment for inoperable angiosarcoma.

person Hye Ryeon Kim Dong-A University Hospital, Busan, South Korea info_outline Hye Ryeon Kim, Miso Kim, Jeong Eun Kim, Hyojeong Kim, Yu Jung Kim, Myoung Joo Kang, Kwonoh Park, Woo Kyun Bae, Jung Yong Hong, Sung Yong Oh

Authors person Hye Ryeon Kim Dong-A University Hospital, Busan, South Korea info_outline Hye Ryeon Kim, Miso Kim, Jeong Eun Kim, Hyojeong Kim, Yu Jung Kim, Myoung Joo Kang, Kwonoh Park, Woo Kyun Bae, Jung Yong Hong, Sung Yong Oh Organizations Dong-A University Hospital, Busan, South Korea, Department of Internal Medicine, Seoul National University Hospital, Seoul, South Korea, Department of Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea, Division of Hemato-oncology, Department of Internal Medicine, Pusan National University School of Medicine, Busan, South Korea, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, South Korea, Division of Hematology-Oncology, Department of Internal Medicine, Inje University Haeundae Paik Hospital, Busan, South Korea, Medical Oncology and Hematology, Department of Internal Medicine, Pusan National University Yangsan Hospital, Yangsan, South Korea, Division of Hemato-Oncology, Department of Internal Medicine, Chonnam National University Hwasun Hospital, Hwasun, Republic of Korea, Hwasun-Gun, South Korea, Samsung Medical Center, Seoul, South Korea, Donga University Hospital, Busan, South Korea Abstract Disclosures Research Funding The healthcare business of Merk KGaA, Darmstadt, Germany (CrossRef Funder ID: 10.13039/100009945) Background: Angiosarcomas are very rare tumors of vascular or lymphatic origin characterized by a clinical heterogeneity in terms of presentation and behavior. It can occur in any site of body but most commonly originate in the skin of head and neck and in breast area. Many patients could not receive surgical resection due to its location and/or rapid progression, even who had localized disease. Moreover, conventional cytotoxic chemotherapy has shown limited effect in angiosarcoma. Here, we conduct a prospective, phase II study to evaluate the efficacy and toxicities of paclitaxel plus avelumab as the first line therapy for unresectable angiosarcoma. Methods: Patients with unresectable locally advanced or metastatic angiosarcoma, who had not received systemic treatment, were enrolled. Paclitaxel (80 mg/m 2 ) was intravenously infused on days 1, 8, and 15 of every 28-days cycle, and avelumab (10mg/kg) was intravenously infused biweekly. The treatment was continued until disease progression or unacceptable toxicity, or withdrawal of consent, whichever occurred first. The primary endpoint was the objective response rate (ORR), and the secondary endpoint was overall survival (OS), progression free survival (PFS), and safety profiles. Results: A total 32 patients (21 male, 11 female) were finally enrolled, and the median age was 63.5 (range, 27 to 82). The ORR was 50.0% (n = 16), including one complete response. Median OS and PFS were 14.5 (95% CI, 9.4 to 24.6) and 6.0 (95% CI, 5.4 to 9.5) months, respectively. Among patients who received at least one dose of treatment (n = 33), adverse events (AEs) of any grade were reported in 90.9% (n = 30), and severe AEs were in 12.1% (n = 4), including one death. The most common hematologic/non-hematologic AEs were neutropenia (n = 13, 39.4%) and pain (n = 12, 36.4%), respectively. Febrile neutropenia, neutropenia, and aspiration were reported in two patients (6.1%) each. Conclusions: Avelumab plus paclitaxel for patients with inoperable angiosarcoma, was effective and has tolerable safety profile. Additional translation studies and phase III studies are needed to clearly identify effectiveness and safety. Clinical trial information: NCT03512834. Best Response n (%) Complete response 1 (3.1%) Partial response 15 (46.9%) Stable disease 14 (43.8%) Progressive disase 2 (6.2%) Objective response rate 16 (50.0%) Clinical benefit rate 30 (93.8%) Overall survival 14.5 mo (95% CI, 9.4 - 24.6) Progression free survival 6.0 mo (95% CI, 5.4 - 9.5)

Clinical