Feasibility and tolerability of sintilimab plus anlotinib as the second-line therapy for patients with advanced biliary tract cancers: An open-label, single-arm, phase II clinical trial

Patients with biliary tract cancer (BTC) were associated with poor prognosis and limited therapeutic options after first-line therapy currently. In this study, we sought to evaluate the feasibility and tolerability of sintilimab plus anlotinib as the second-line treatment for patients with advanced BTC. Eligible patients had histologically confirmed locally advanced unresectable or metastatic BTC and failed after the first-line treatment were recruited. The primary endpoint was overall survival (OS). Simultaneously, association between clinical outcomes and genomic profiling and gut microbiome were explored to identify the potential biomarkers for this regimen. Twenty patients were consecutively enrolled and received study therapy. The trail met its primary endpoint with a median OS of 12.3 months (95% CI: 10.1-14.5). Only four (20%) patients were observed of the grade 3 treatment-related adverse events (TRAEs) and no grade 4 or 5 TRAEs were detected. Mutation of AGO2 was correlated with a significantly longer OS. Abundance of Proteobacteria was associated with inferior clinical response. Therefore, sintilimab plus anlotinib demonstrated encouraging anti-tumor activity with a tolerable safety profile and deserved to be investigated in larger randomized trials for patients with advanced BTC subsequently.

Regorafenib after failure of gemcitabine and platinum-based chemotherapy for locally advanced/metastatic biliary tumors: REACHIN, a randomized, double-blind, phase II trial

BACKGROUND

There is a high unmet clinical need for treatments of advanced/metastatic biliary tract cancers after progression on first-line chemotherapy. Regorafenib has demonstrated efficacy in some gastrointestinal tumors that progress on standard therapies.

PATIENTS AND METHODS

REACHIN was a multicenter, double-blind, placebo-controlled, randomized phase II study designed to evaluate the safety and efficacy of regorafenib in patients with nonresectable/metastatic biliary tract cancer that progressed after gemcitabine/platinum chemotherapy. Patients were randomly assigned 1 : 1 to best supportive care plus either regorafenib 160 mg once daily 3 weeks on/1 week off or placebo until progression or unacceptable toxicity. No crossover was allowed. The primary objective was progression-free survival (PFS). Secondary objectives were response rate, overall survival, and translational analysis.

RESULTS

Sixty-six patients with intrahepatic (n = 42), perihilar (n = 6), or extrahepatic (n = 9) cholangiocarcinoma, or gallbladder carcinoma (n = 9) were randomized, 33 to each treatment group (33 per group). At a median follow-up of 24 months, all patients had progressed and six patients were alive. Median treatment duration was 11.0 weeks [95% confidence interval (CI): 6.0-15.9] in the regorafenib group and 6.3 weeks (95% CI: 3.9-7.0) in the placebo group (P = 0.002). Fourteen of 33 patients (42%) in the regorafenib group had a dose reduction. Stable disease rates were 74% (95% CI: 59-90) in the regorafenib group and 34% with placebo (95% CI: 18-51; P = 0.002). Median PFS in the regorafenib group was 3.0 months (95% CI: 2.3-4.9) and 1.5 months (95% CI: 1.2-2.0) in the placebo group (hazard ratio 0.49; 95% CI: 0.29-0.81; P = 0.004) and median overall survival was 5.3 months (95% CI: 2.7-10.5) and 5.1 months (95% CI: 3.0-6.4), respectively (P = 0.28). There were no unexpected/new safety signals.

CONCLUSION

Regorafenib significantly improved PFS and tumor control in patients with previously treated metastatic/unresectable biliary tract cancer in the second- or third-line setting.

CLINICAL TRIAL REGISTRATION

The trial is registered in the European Clinical Trials Register database (EudraCT 2012-005626-30) and at ClinicalTrials.gov (NCT02162914).

mTOR Inhibitors in Advanced Biliary Tract Cancers

Patients with advanced biliary tract cancers (BTCs), including cholangiocarcinoma (CCA), have poor prognosis so novel treatment is warranted for advanced BTC. In current review, we discuss the limitations of current treatment in BTC, the importance of mTOR signalling in BTC, and the possible role of mTOR inhibitors as a future treatment in BTC. Chemotherapy with gemcitabine-based chemotherapy is still the standard of care and no targeted therapy has been established in advanced BTC. PI3K/AKT/mTOR signaling pathway linking to several other pathways and networks regulates cancer proliferation and progression. Emerging evidences reveal mTOR activation is associated with tumorigenesis and drug-resistance in BTC. Rapalogs, such as sirolimus and everolimus, partially inhibit mTOR complex 1 (mTORC1) and exhibit anti-cancer activity in vitro and in vivo in BTC. Rapalogs in clinical trials demonstrate some activity in patients with advanced BTC. New-generation mTOR inhibitors against ATP-binding pocket inhibit both TORC1 and TORC2 and demonstrate more potent anti-tumor effects in vitro and in vivo, however, prospective clinical trials are warranted to prove its efficacy in patients with advanced BTC.

Recent advances for the treatment of pancreatic and biliary tract cancer after first-line treatment failure

Here, we evaluate clinical trials on chemotherapy for patients with pancreatic or biliary tract cancer after first-line treatment failure. Clinical trials on conventional and innovative medical treatments for progressive pancreatic and biliary cancer were analyzed. Metronomic chemotherapy, which consists of the administration of continuative low-dose of anticancer drugs, was also considered. A significant extension of overall survival was achieved with second-line, regimens in patients with gemcitabine-refractory pancreatic cancer. Moreover, many Phase II studies, including chemotherapy and target molecules and immunotherapy, have reported promising results, in both pancreatic and biliary cancer. However, data in these patients' setting are very heterogeneous, and only few randomized studies are available.