As reported in the Journal of Clinical Oncology by Cannon et al, findings in a cohort of the phase II Targeted Agent and Profiling Utilization Registry (TAPUR) basket study showed that the combination of pertuzumab and trastuzumab was active in patients with advanced biliary tract cancer with HER2/3 amplification, overexpression, or mutation.
Study Details
Twenty-nine patients were enrolled in the multicenter study between February 2017 and January 2022. They received pertuzumab once every 3 weeks at an initial dose of 840 mg followed by 420 mg and trastuzumab once every 3 weeks at an initial dose of 8 mg/kg followed by 6 mg/kg. Treatment continued until disease progression or unacceptable toxicity. The primary outcome measure of the investigation was disease control, defined as objective response or stable disease lasting 16+ weeks.
Key Findings
Among 28 patients evaluable for efficacy, disease control was achieved in 11 (40%, 90% confidence interval [CI] = 27%–100%) and objective responses were seen in 9 (1 complete, 8 partial; 32%, 95% CI = 16%–52%); the null hypothesis of a disease control rate of 15% was rejected (P = .0015). The duration of response in the one patient with a complete response was 71 weeks; median response duration among the eight patients with a partial response was 30 weeks (range = 4–69 weeks).
Median progression-free survival was 11 weeks (95% CI = 8–16 weeks) and median overall survival was 30 weeks (95% CI = 17–49 weeks).
Among 29 patients in the safety population, 3 (10%) had grade 3 adverse events considered at least possibly related to treatment (anemia, diarrhea, and fatigue) and one patient (3%) had a treatment-related serious adverse event (infusion-related reaction). No grade 4 or 5 adverse events were observed.
The investigators concluded, “Pertuzumab plus trastuzumab met prespecified criteria to declare a signal of activity in patients with biliary tract cancer and HER2/3 amplification, overexpression, or mutation.”
Pam K. Mangat, MS, of the American Society of Clinical Oncology, is the corresponding author for the Journal of Clinical Oncology article.
Disclosure: The study was supported by Genentech and others. For full disclosures of the study authors, visit ascopubs.org.
