BeiGene Presents Clinical Data from Two Phase 2 Trials of Pamiparib at the 2021 ASCO Annual Meeting - Seite 2

“Studies have suggested that breast cancer with germline BRCA mutations may be susceptible to PARP inhibition. These Phase 2 results demonstrated pamiparib’s efficacy in patients with HR(+)/HER2(-) breast cancer, as well as in triple-negative breast cancer, one of the most aggressive forms of the disease with the poorest outcomes,” said Binghe Xu, M.D., Ph.D., Cancer Hospital Chinese Academy of Medical Sciences and a principal investigator of the trial. “In addition to demonstrating positive response rates, the trial suggested pamiparib may show promise in progression-free survival benefits and we look forward to further research of pamiparib in this patient population, who are in great need of additional treatment options.”

At the data cut-off on October 9, 2020, the median follow-up time was 13.8 months (TNBC cohort, 10.9 months; HR[+] cohort, 18.5 months).

Pamiparib demonstrated meaningful and durable clinical activity in patients across both cohorts. Efficacy results included:

• Confirmed ORR as assessed by IRC, the primary efficacy endpoint, was 61.9% (95% CI: 38.4, 81.9) in the HR(+) cohort and 38.2% (95% CI: 25.4, 52.3) in the TNBC cohort;
• Four patients achieved a complete response (CR), including three in the TNBC cohort and one patient in the HR(+) cohort;
• 18 patients in the TNBC cohort and 12 patients in the HR(+) cohort demonstrated a partial response (PR);
• DCR as assessed by IRC was 90.5% (95% CI: 69.6, 98.8) in the HR(+) cohort and 72.7% (95% CI: 59.0, 83.9) in the TNBC cohort;
• Additionally, CBR as assessed by IRC was 71.4% (95% CI: 47.8, 88.7) in the HR(+) cohort and 43.6% (95% CI: 30.3, 57.7) in the TNBC cohort;
• Patients in the HR(+) cohort had a median DoR of 7.5 months (95% CI: 5.6, 14.8) and patients in the TNBC cohort had a median DoR of 7.0 months (95% CI: 3.9, not estimable [NE]);
• The median PFS was 9.2 months (95% CI: 7.4, 11.9) in the HR(+) cohort and 5.5 months (95% CI: 3.7, 7.3) in the TNBC cohort; and
• In the trial, the median OS in the TNBC cohort was 17.1 months (95% CI:13.7, NE) and was not reached in the HR(+) cohort (NE; 95% CI: 18.1, NE).

Pamiparib was generally well-tolerated, and results from the safety analysis for all 88 patients across both cohorts included: