Nab-Paclitaxel plus Sintilimab as Second-Line Treatment for Advanced BTC

Although a first-line standard of care for the treatment of advanced biliary tract cancer (BTC) has been established, a lack of consensus is seen regarding the optimal second-line treatment in patients without genetic abnormalities. Because immune checkpoint inhibitors have demonstrated promising efficacy in patients with advanced BTC, it has been suggested that there may be a potential role for them in the second line. Dr Xiaofen Li presented results from NapaSinti, a prospective single-arm, phase 2 study investigating the safety and efficacy of second-line nab-paclitaxel combined with anti–PD-1 antibody sintilimab in patients with advanced BTC.

Eligible patients 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.

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. 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.

Overall, nab-paclitaxel plus sintilimab has demonstrated promising activity as a second-line treatment option for patients with advanced BTC. NGS may aid in the detection of relevant biomarkers that have the potential to predict efficacy and clinical benefit.

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.