Immunotherapies in non-metastatic gastrointestinal cancers

PURPOSE

Over the last decade, immune checkpoint inhibitors (ICI) have emerged as cornerstone in the treatment of many metastatic tumour types, including gastrointestinal cancers. In many solid tumours, the effective therapies in the metastatic field are progressively brought into the curative setting. Consequently, earlier tumoural settings have become a field of experiment for immunotherapies. In melanoma, lung, and bladder cancers, excellent results were recorded, possibly explained by differences in the tumour microenvironment between metastatic and non-metastatic settings. In gastrointestinal (GI) Oncology, nivolumab is the first immune checkpoint inhibitor to become a standard-of-care adjuvant treatment after curative surgery for oesophagal or gastroesophageal junction cancer.

RECENT FINDINGS

We herein discuss the results of a selection of the most relevant studies presented/published over the last 18 months testing immunotherapies in non-metastatic GI cancers. Among immunotherapies, ICI have been investigated in pre-, peri- and postoperative setting across tumour types, alone or in combination with chemo- and/or radiotherapy. Vaccines are also a new field of investigation.

SUMMARY

Promising results from two studies (NCT04165772 and NICHE-2 study) demonstrating never-seen-before responses to neoadjuvant immunotherapy in MMR deficient (dMMR) colorectal cancers raise hope for improving the patients' outcome and developing organ-sparing strategies in this situation.

Phase Ib study of anlotinib combined with TQB2450 in pretreated advanced biliary tract cancer and biomarker analysis

BACKGROUND AND AIMS

We evaluated the efficacy and safety of the antiangiogenic tyrosine kinase inhibitor anlotinib plus TQB2450, a programmed death-ligand 1 inhibitor in pretreated advanced biliary tract cancers (BTCs).

APPROACH AND RESULTS

In this pooled analysis of two single-center, phase Ib clinical trials (TQB2450-Ib-05 and TQB2450-Ib-08 trials), 66 patients with advanced BTCs who had progressed or declined or were ineligible for first-line chemotherapy were included. With the treatment of anlotinib plus TQB2450, two patients achieved complete response, and 12 had a partial response assessed by Response Evaluation Criteria in Solid Tumors 1.1, yielding an objective response rate of 21.21%, a disease control rate (DCR) of 72.73%, and a clinical benefit rate (CBR) of 42.42%. With a median follow-up of 19.68 months, median progression-free survival (PFS) and overall survival (OS) were 6.24 (95% confidence interval [CI], 4.11-8.25) and 15.77 (95% CI, 10.74-19.71) months, respectively. Adverse events (AEs) were reported in 64 (96.97%) patients, and the most common grade 3 or worse treatment-related AEs included elevated levels of aspartate aminotransferase (7.58%), alanine aminotransferase (6.06%), and hypertension (6.06%). Patients with high tumor mutational burden (TMB; ≥5 mutations/Mbp) had a better CBR (70.8% vs. 22.2%), longer OS (14.32 vs. 9.64 months), and a trend toward longer PFS (7.03 vs. 4.06 months). Patients with kirsten rat sarcoma viral oncogene homolog ( KRAS ) mutations showed a lower CBR (12.5% vs. 58.8%) and shorter PFS (2.02 vs. 6.80 months) and OS (10.53 vs. 13.13 months).

CONCLUSIONS

Anlotinib combined with TQB2450 showed promising efficacy and was well tolerated in advanced BTCs. KRAS mutation and high TMB might serve as predictors of treatment efficacy.

Current and emerging immunotherapeutic approaches for biliary tract cancers

BACKGROUND

Biliary tract cancers (BTCs) comprise a heterogeneous group of aggressive malignancies with unfavorable prognoses. The benefit of chemotherapy seems to have reached a bottleneck and, therefore, new effective therapeutic strategies for advanced BTCs are needed. Molecularly targeted therapies in selected patients are rapidly changing the situation. However, the low frequency of specific driver alterations in BTCs limits their wide application. Recently, immunotherapeutic approaches are also under active investigation in BTCs, but the role of immunotherapy in BTCs remains controversial.

DATA SOURCES

PubMed, Web of Science, and meeting resources were searched for relevant articles published from January 2017 to May 2022. The search aimed to identify current and emerging immunotherapeutic approaches for BTCs. Information on clinical trials was obtained from https://clinicaltrials.gov/ and http://www.chictr.org.cn/.

RESULTS

Immunotherapy in BTC patients is currently under investigation, and most of the investigations focused on the application of immune checkpoint inhibitors (ICIs). However, only a subgroup of BTCs with microsatellite-instability high (MSI-H)/DNA mismatch repair-deficient (dMMR) or tumor mutational burden-high (TMB-H) benefit from monotherapy of ICIs, and limited activity was observed in the second or subsequent settings. Nevertheless, promising results come from studies of ICIs in combination with other therapeutic approaches, including chemotherapy, in advanced BTCs, with a moderate toxicity profile. Recent studies demonstrated that compared to GEMCIS alone, durvalumab plus GEMCIS significantly improved patient survival (TOPAZ-1 trial) and that ICIs-combined chemoimmunotherapy is poised to become a new frontline therapy option, regardless of TMB and MMR/MSI status. Adoptive cell therapy and peptide- or dendritic-based cancer vaccines are other immunotherapeutic options that are being studied in BTCs. Numerous biomarkers have been investigated to define their predictive role in response to ICIs, but no predictive biomarker has been validated, except MSI-H/dMMR.

CONCLUSIONS

The role of immunotherapy in BTCs is currently under investigation and the results of ongoing studies are eagerly anticipated. Several studies have demonstrated the safety and efficacy of ICIs in combination with chemotherapy in treatment-naive patients, such as the phase III TOPAZ-1 trial, which will change the standard care of first-line chemotherapy for advanced BTCs. However, further research is needed to understand the best combination with immunotherapy and to discover more predictive biomarkers to guide clinical practice.

Immunotherapy in biliary tract cancers: Current evidence and future perspectives

Bile duct tumors are comprised of tumors that originate from both intrahepatic and extrahepatic bile ducts and gallbladder tumors. These are aggressive tumors and chemotherapy is still the main treatment for advanced-stage disease and most of these cases have a poor overall survival. Strategies are aimed at treatments with better outcomes and less toxicity which makes immunotherapy an area of ​​significant importance. Recent Food and Drug Administration approvals of immune checkpoint inhibitors (ICI) for agnostic tumors based on biomarkers such as microsatellite instability-high and tumor mutation burden-high are important steps in the treatment of patients with advanced bile duct tumors. Despite limited responses with isolated checkpoint inhibitors in later lines of systemic treatment in advanced disease, drug combination strategies have been demonstrating encouraging results to enhance ICI efficacy.

Efficacy and Safety of Anti-PD1/PDL1 in Advanced Biliary Tract Cancer: A Systematic Review and Meta-Analysis

Background

Anti-programmed cell death protein 1 and its ligand (anti-PD1/PDL1) have been proposed as a promising therapeutic option for advanced biliary tract cancer (aBTC). Given the scarce quantitative analyses of anti-PD1/PDL1 in aBTC, we thus did a meta-analysis to assess the benefits and risks of this emerging treatment strategy in patients with aBTC.

Methods

PubMed, Embase, the Cochrane Library, Web of Science, and meeting resources were searched for relevant studies. The main endpoints were median progression-free survival (mPFS), median overall survival (mOS), objective response rate (ORR), disease control rate (DCR), any-grade adverse events (AEs), and grade 3-4 AEs.

Results

Twenty-eight studies with 1,338 participants were included. The best curative effect was found in the anti-PD1/PDL1 combined with anti-CTLA4 and chemotherapy group (mPFS: 12.4 months; mOS: 16.0 months; ORR: 45.1%; DCR: 95.0%), followed by the anti-PD1/PDL1 plus chemotherapy group (mPFS: 8.2 months; mOS: 14.8 months; ORR: 36.3%; DCR: 84.6%), the anti-PD1/PDL1 plus antiangiogenesis group (mPFS: 4.9 months; mOS: 10.2 months; ORR: 17.5%; DCR: 68.7%), the anti-PD1/PDL1 plus anti-cytotoxic T lymphocyte antigen 4 (anti-CTLA4) group (mPFS: 2.9 months; mOS: 8.3 months; ORR: 9.9%; DCR: 36.8%), and the anti-PD1/PDL1 monotherapy group (mPFS: 2.5 months; mOS: 7.6 months; ORR: 6.8%; DCR: 34.7%). Compared with anti-PD1-containing regimens, anti-PDL1-containing regimens achieved preferable mPFS (11.1 vs. 3.8 months), mOS (12.2 vs. 9.8 months), and ORR (23.7% vs. 17.4%), despite a similar DCR (61.1% vs. 61.3%). The mPFS, mOS, ORR, and DCR were 10.6 months, 15.8 months, 42.3%, and 88.6% of first-line anti-PD1/PDL1 and 3.0 months, 9.1 months, 11.6%, and 51.1% of second-line therapy or beyond, respectively. There were 80.6% and 34.0% of the patients suffering any-grade AEs and grade 3-4 AEs. Anti-PD1/PDL1 monotherapy might be considered as a safer alternative than combination regimens. Meanwhile, obvious toxicities in the first-line setting could not be neglected.

Conclusions

Anti-PD1/PDL1 showed encouraging efficacy and acceptable safety profile in aBTC and, thus, could be an alternative treatment.

Immunotherapy for cholangiocarcinoma: a 2021 update

Cholangiocarcinoma (CCA) is a rare malignancy with generally dismal prognosis. Immunotherapy has revolutionized the management of cancer patients during the last decade, offering durable responses with an acceptable safety profile, but there are still no significant advances regarding CCA. Novel immunotherapeutic methods, such as cancer vaccines, oncolytic viruses, adoptive cell therapy and combinations of immune checkpoint inhibitors with other agents are currently under investigation and may improve prognosis. Efforts to find robust biomarkers for response are also ongoing. In this review, we discuss the rationale for the use of immunotherapy in CCA and available clinical data. Ongoing trials will also be presented, as well as key findings from each study.