Nab-Paclitaxel Plus Sintilimab as Second-Line Treatment for Patients With Advanced BTC: A Phase 2 Study

A single-arm, phase 2 study investigated the safety and efficacy of second-line nab-paclitaxel combined with the anti–PD-1 antibody sintilimab in patients with advanced biliary tract cancer.

Despite the availability of a first-line standard of care for the treatment of advanced biliary tract cancer (BTC), there is no universal agreement on the best second-line therapy for individuals without genetic abnormalities. Immune checkpoint inhibitors have shown promising efficacy in patients with advanced BTC, leading some to speculate that they could have a place in second-line therapy. At the 2023 ASCO Gastrointestinal Cancers Symposium, Dr Xiaofen Li presented the findings from NapaSinti, a prospective single-arm, phase 2 study examining the safety and efficacy of second-line nab-paclitaxel combined with the anti–PD-1 antibody sintilimab in patients with advanced BTC.

Patients were eligible if they had advanced BTC and were treated with gemcitabine or fluorouracil-based chemotherapy in the first line; patients could not have received prior paclitaxel therapy. Eligible patients received sintilimab plus nab-paclitaxel for up to 8 cycles followed by maintenance treatment with sintilimab for up to 24 months or until disease progression, unacceptable toxicity, or patient withdrawal. The primary end point was objective response rate (ORR), and key secondary end points included progression-free survival (PFS), overall survival (OS), and safety.

Dr Xiaofen Li presented the findings from NapaSinti, a prospective single-arm, phase 2 study examining the safety and efficacy of second-line nab-paclitaxel combined with the anti–PD-1 antibody sintilimab in patients with advanced BTC.

A total of 24 patients, 22 with available efficacy evaluation, were included. The ORR was 27.3%, with 1 complete response and 5 partial responses. The disease control rate was 83.6%, the median PFS was 5.6 months (95% confidence interval [CI], 1.92-9.35), and the median OS was 12.6 months (95% CI, 7.84-17.36).

The most common grade 3 adverse events were leukopenia in 16.7% of patients, anemia in 12.5% of patients, and neutropenia and peripheral neuropathy in 8.3% of patients. Of the 24 patients studied, 11 had next-generation sequencing (NGS) testing; of these, 5 patients harbored TP53 mutations, 4 had DNA damage response–pathway mutations, 1 patient had an IDH1 mutation, and 1 patient was microsatellite instability-high. Finally, 2 patients with TP53 mutations and 2 patients with DNA damage–response mutations achieved a partial response.

For individuals with advanced BTC, nab-paclitaxel plus sintilimab has generally shown encouraging efficacy as a second-line therapeutic option. NGS might be useful to help find pertinent biomarkers that could be used to predict clinical benefit and efficacy.

Source:

Li X, Zhou N, Yang Y, Gou H. Nab-paclitaxel plus anti-PD-1 antibody as second-line treatment for advanced biliary tract cancer: an investigator-initiated phase 2 study (NapaSinti trial). Poster presented at: ASCO Gastrointestinal Cancers Symposium, January 19-21, 2023; San Francisco, CA. Abstract 564.