Pazopanib Efficacy May Depend on Histologic Types of Soft Tissue Sarcoma

There appear to be differences in the efficacy of pazopanib treatment among histologic types of soft tissue sarcoma, a study published in the journal Cancer has shown.¹

Pazopanib was approved by the U.S. Food and Drug Administration for the treatment of patients with advanced soft tissue sarcoma who have received prior chemotherapy. Approval was based on findings from the PALETTE study, which demonstrated a 3-month improvement in median progression-free survival with pazopanib compared with placebo.

Because the efficacy and safety of pazopanib in Japanese patients with soft tissue sarcoma had not been evaluated previously in a large-scale cohort, the researchers sought to assess the efficacy and safety of pazopanib in 156 Japanese patients with relapsed disease.

For the retrospective study, researchers analyzed the real-life, postmarketing surveillance data of 20 patients with local recurrence, 104 with metastasis, and 32 with both.

Results showed that median progression-free survival was 15.4 weeks. Median progression-free survival for patients with leiomyosarcoma, synovial sarcoma, undifferentiated pleomorphic sarcoma, and liposarcoma was 18.6 weeks, 16.4 weeks, 15.3 weeks, and 8 weeks, respectively.

Median survival for all patients was 11.2 months, and was 20.1 months, 10.6 months, 9.5 months, and 7.3 months for patients with leiomyosarcoma, synovial sarcoma, undifferentiated pleomorphic sarcoma, and liposarcoma, respectively.

In terms of safety, researchers found that pneumothorax and thrombocytopenia had occurred frequently, in addition to the main common toxicities like hypertension and liver enzyme abnormalities.

Reference

1. Nakamura T, Matsumine A, Kawai A, et al. The clinical outcome of pazopanib treatment in Japanese patients with relapsed soft tissue sarcoma: a Japanese Musculoskeletal Oncology Group (JMOG) study [published online ahead of print March 11, 2016]. Cancer. doi: 10.1002/cncr.29961.