Single-agent Dasatinib May Be Active in Undifferentiated Pleomorphic Sarcoma
Dasatinib may have activity in patients with undifferentiated pleomorphic sarcoma but is not an effective monotherapy for other sarcoma types.
Dasatinib may have activity in patients with undifferentiated pleomorphic sarcoma but it is inactive as monotherapy in other sarcoma types, including leiomyosarcoma and rhabdomyosarcoma.1
Because dasatinib exhibited activity in preclinical models of sarcoma, researchers at the Sarcoma Alliance for Research through Collaboration (SARC) sought to evaluate the activity of single-agent dasatinib in patients with advanced sarcoma.
For the multicenter, phase 2 trial, researchers enrolled a total of 200 patients and were assigned to 1 of 7 different cohorts based on sarcoma subtype. All patients received dasatinib twice daily and were assessed by imaging every 8 weeks.
Due to a low estimated clinical benefit rate in 5 cohorts, the investigators stopped accrual in those cohorts early. Results showed that 8 of 42 evaluable patients with undifferentiated pleomorphic sarcoma and 6 of 47 evaluable patients with leiomyosarcoma demonstrated a clinical benefit. Researchers found that the probability that the clinical benefit rate was 25% or higher was 0.10 in the undifferentiated pleomorphic sarcoma group, but only 0.008 in the leiomyosarcoma group.
Median progression-free survival ranged from 0.9 months in patients with rhabdomyosarcoma to 2.2 months in patients with leiomyosarcoma, and the median overall survival was 8.6 months.
In regard to safety, 11% of patients experienced treatment-related serious adverse events with 36% of patients requiring dose reduction for toxicity. The most frequent adverse events were constitutional, gastrointestinal, and respiratory.
- Schuetza SM, Wathen JK, Lucas DR, et al. SARC009: Phase 2 study of dasatinib in patients with previously treated, high-grade, advanced sarcoma [published online ahead of print December 28, 2015]. Cancer. doi: 10.1002/cncr.29858.