Zanidatamab for HER2-amplified, unresectable, locally advanced or metastatic biliary tract cancer (HERIZON-BTC-01): a multicentre, single-arm, phase 2b study

Antibodies to watch in 2025

The commercial development of antibody therapeutics is a global enterprise involving thousands of biopharmaceutical firms and supporting service organizations. To date, their combined efforts have resulted in over 200 marketed antibody therapeutics and a pipeline of nearly 1,400 investigational product candidates that are undergoing evaluation in clinical studies as treatments for a wide variety of diseases. Here, we discuss key events in antibody therapeutics development that occurred during 2024 and forecast key events related to the late-stage clinical pipeline that may occur in 2025. In particular, we report on 21 antibody therapeutics granted a first approval in at least one country or region during 2024, including bispecific antibodies tarlatamab (IMDELLTRA®), zanidatamab (Ziihera®), zenocutuzumab (BIZENGRI®), odronextamab (Ordspono®), ivonescimab (®), and antibody-drug conjugate (ADC) sacituzumab tirumotecan (®). We also discuss 30 investigational antibody therapeutics for which marketing applications were undergoing review by at least one regulatory agency, as of our last update on December 9, 2024, including ADCs datopotamab deruxtecan, telisotuzumab vedotin, patritumab deruxtecan, trastuzumab botidotin, becotatug vedotin, and trastuzumab rezetecan. Of 178 antibody therapeutics we include in the late-stage pipeline, we summarize key data for 18 for which marketing applications may be submitted by the end of 2025, such as bi- or multispecific antibodies denecimig, sonelokimab, erfonrilimab, and anbenitamab. Key trends in the development and approval of antibody formats such as bispecifics and ADCs, as well as clinical-phase transition and global approval success rates for these antibody formats, are reported.

Real-world efficacy of zanidatamab in patients with HER2 positive advanced biliary tract cancers

INTRODUCTION

In the HERIZON BTC 01 trial for patients with HER2-positive biliary tract cancer (BTC) previously treated with systemic therapy, zanidatamab improved the objective response rate, disease control rate (DCR), progression-free survival (PFS), and overall survival (OS). However, real-world data are needed to assess its efficacy and safety outside clinical trials.

PATIENTS & METHODS

We conducted an investigator initiated national multicenter retrospective study of most patients with BTC treated with zanidatamab in France as part of a compassionate access. The primary endpoint was PFS.

RESULTS

Our study included 20 patients with metastatic BTC enrolled between September 2022 and November 2024. The median age at diagnosis was 61.5 (interquartile range: 55-69) years and the majority of patients had gallbladder cancer (n = 12, 60 %). After a median follow-up of 8.5 (95 % confidence interval [CI]: 3.3-11.8) months, the median PFS was 6.7 (95 % CI 1.3-11.8) months, with an estimated OS at 1 year of 79.1 % (95 % CI: 53.2-91.6 %). The DCR was 65 %, with 40 % confirmed partial responses and a median duration of response of 7.3 (95 % CI: 2.06-16) months. Patients with immunohistochemistry (IHC) 3 + HER2 scores had a better PFS [8 (95 % CI: 1.5-18.4) months] than those with 2 + HER2 scores obtained by IHC followed by fluorescence in situ hybridization amplification or next-generation sequencing [1.4 (95 % CI: 1.1-6.8) months] (P = 0.02). No statistical difference in 1-year estimated OS rates was observed (P = 0.39). There were no grade 3 or 4 treatment-related adverse events or cardiac toxicities.

CONCLUSION

The benefits of in patients with HER2-positive BTC were confirmed. Zanidatamab should be considered for patients with this condition.

Bispecific Antibodies in Hematologic and Solid Tumors: Current Landscape and Therapeutic Advances

Bispecific antibodies (bsAbs) have emerged as a novel class of therapeutics, offering a dual-targeting strategy to enhance the therapeutic efficacy of monoclonal antibodies, which is often limited by tumor heterogeneity and the occurrence of resistance mechanisms. By simultaneously engaging two distinct antigens or pathways, bsAbs disrupt multiple signaling cascades simultaneously, preventing escape mechanisms and offering a more durable response. Furthermore, they can optimize immune activation, improving immune cell recruitment strategies. In particular, T-cell engager bsAbs facilitate immune cell-mediated tumor destruction by linking T cells to tumor antigens. Instead, dual immune checkpoint inhibitors (CPIs) enhance immune activation by blocking inhibitory signals. Additionally, bsAbs targeting tumor growth factors or receptor tyrosine kinases offer solutions for overcoming drug resistance in solid tumors. Although bsAbs have shown remarkable success in hematologic malignancies, their expansion into solid tumors faces key challenges, including tumor heterogeneity, limited tumor penetration, and the risk of on-target, off-tumor toxicities. Addressing these challenges requires innovative engineering strategies, optimized delivery mechanisms, and careful patient selection to maximize therapeutic benefit while mitigating adverse effects. The efficacy of bsAbs in clinical trials has led to their approval for both hematologic and solid malignancies, with numerous agents in development. Combination strategies with chemotherapy, targeted agents, and immune CPIs could represent a promising strategy to further expand their potential. As research progresses, bsAbs are expected to play a role in reshaping the future of precision oncology, offering more effective and tailored treatment options.

Genomic landscape of biliary tract cancer and corresponding targeted treatment strategies

Biliary tract cancers (BTCs) are classified on the basis of their anatomical origin, and the feasibility of surgical resection depends on the tumor location and extent of progression. However, for unresectable BTCs, systemic therapy has been uniformly applied. Gemcitabine and cisplatin (GC) therapy and GC-based therapies were established as the first-line standard BTC treatment. However, no highly effective second-line therapy has been established, and the prognosis remains poor, highlighting the need for further therapeutic advancements. Meanwhile, the era of precision medicine has expanded the use of genetic testing, leading to the identification of actionable molecular targets in BTC. Several targeted therapies, including FGFR inhibitors and IDH1 inhibitors, have been developed, offering new second-line treatment options and the potential for first-line use in appropriate cases. Notably, the frequency of these genetic alterations varies depending on the tumor location, demonstrating the molecular heterogeneity of BTC. Therefore, it has been recognized that a tailored treatment approach for each BTC patient may be more effective than uniform systemic therapy. Consequently, although routine genetic testing before initiating systemic treatment is currently limited by the medical environment (e.g., cost, accessibility, regional differences), it is recommended in ESMO guideline and might be increasingly advocated. However, BTC harbors a wide range of genetic alterations, and numerous targeted therapies are being developed accordingly. This review provides an overview of the reported genetic alterations in BTC, the frequencies of these alterations, and the corresponding targeted therapies, emphasizing the evolving role of precision medicine in BTC treatment.

Zanidatamab plus palbociclib and fulvestrant in previously treated patients with hormone receptor-positive, HER2-positive metastatic breast cancer: primary results from a two-part, multicentre, single-arm, phase 2a study

BACKGROUND

New HER2-targeted regimens, including chemotherapy-free options, are needed for metastatic breast cancer. In an ongoing, two-part, phase 2a study, we assessed the safety and antitumour activity of zanidatamab, a HER2-targeted bispecific antibody, plus palbociclib and fulvestrant, in heavily pretreated patients with hormone receptor-positive, HER2-positive advanced or metastatic breast cancer.

METHODS

This multicentre, single-arm, two-part, phase 2a study is being conducted at 13 university hospitals, cancer centres, or research institutes in Spain, Canada, and the USA. Eligible patients were adults (aged ≥18 years) with an Eastern Cooperative Oncology Group performance status of 0 or 1, and with pathologically confirmed unresectable or metastatic breast cancer, assessed locally to be hormone receptor-positive and HER2-positive, with disease progression during or after previous HER2-targeted therapies. Patients were enrolled in part 1, part 2, or part 1 followed by part 2. In part 1, patients received starting doses of zanidatamab (20 mg/kg intravenously once every 2 weeks on days 1 and 15 of a 28-day cycle) with palbociclib (125 mg orally once a day on days 1-21 of each cycle) and fulvestrant (500 mg intramuscular injection once every 2 weeks for the first three doses [cycle 1: days 1 and 15, cycle 2: day 1], then once every 4 weeks [all subsequent cycles: day 1]). In part 1, primary endpoints were safety of the triplet combination and confirmation of recommended doses for part 2. In part 2, patients received the recommended doses confirmed in part 1, and the primary endpoint was progression-free survival at 6 months. Safety and progression-free survival were assessed in all enrolled patients who received any dose of zanidatamab, palbociclib, or fulvestrant. Patients in part 1 who were treated at the recommended doses were analysed together with the patients in part 2. This study is registered with ClinicalTrials.gov, NCT04224272, and is active with recruitment completed.

FINDINGS

Overall, 51 patients (49 [96%] female and two [4%] male; median age 54·0 [46·0-62·0] years; 42 [82%] White) were enrolled: eight in part 1 (June 10, 2020-Feb 7, 2021) and 43 in part 2 (Feb 8, 2021-Oct 31, 2022). All 51 patients had received study treatment at the data cutoff (Aug 3, 2023); median follow-up was 16·1 months (IQR 9·9-23·4) and the median duration of triplet regimen treatment was 7·4 months (3·4-14·8). The median number of previous HER2-targeted therapies was 4 (IQR 3-4). 12 (24%) of 51 patients had previously received trastuzumab deruxtecan. The planned starting drug doses administered in part 1 of the study were confirmed as the recommended doses for part 2. All 51 patients were treated at the recommended doses. All 51 patients had at least one treatment-related adverse event of any grade, with diarrhoea being the most common (41 [80%] patients, with 34 [67%] having grade 1-2 events). Grade 3 or 4 treatment-related adverse events occurred in 34 (67%) patients, with neutropenia being the most common (26 [51%] patients). One (2%) patient had a serious grade 3 treatment-related adverse event of increased transaminases. No treatment-related deaths occurred. In the overall sample (N=51), progression-free survival at 6 months was 66·7% (95% CI 52·1-79·2).

INTERPRETATION

Zanidatamab plus palbociclib and fulvestrant was generally safe and showed promising antitumour activity, supporting further evaluation of this chemotherapy-free triplet regimen.

FUNDING

Zymeworks, Jazz Pharmaceuticals, and Pfizer.

Phase Ia/Ib Study of Afatinib with Capecitabine in Patients with Refractory Solid Tumors and Pancreaticobiliary Cancers

BACKGROUND

The epidermal growth factor receptor (EGFR) is overactive in many tumors. This phase I trial evaluated the safety and preliminary efficacy of afatinib plus capecitabine in refractory pancreatic ductal adenocarcinoma (PDA), biliary tract cancers (BTC), and other solid tumors.

PATIENTS AND METHODS

The phase Ia study had a 3 + 3 design with capecitabine 1000 mg/m2 twice daily on days 1-14 and afatinib 20 mg, 30 mg, or 40 mg daily in 21-day cycles. In phase Ib, 15 patients, each with PDA and BTC, were treated at maximum tolerated dose (MTD).

RESULTS

A total of 41 patients were enrolled. No dose-limiting toxicities were observed, and the MTD was 40 mg afatinib plus capecitabine. Among 36 response-evaluable patients, one had a partial response (3%), and eight (22%) had stable disease. Median progression-free survival (PFS) was 1.9 months (95% CI 1.0, 2.0) for PDA and 1.9 months (95% CI 1.6, 3.4) for BTC. Median overall survival (OS) was 3.2 months (95% CI 2.0, 5.8) for PDA, and 4.6 months (95% CI 1.9, 6.1) for BTC. Median OS was 5.8 months (95% CI 2.0, 9.6) for KRASWT PDA, and 5.0 months (95% CI 1.6, 6.1) for KRASWT BTC, vs. 3.9 months (95% CI 1.9, 5.8) for KRASMUT PDA and 3.1 months (95% CI 1.0, 22.8) for KRASMUT BTC, respectively.

CONCLUSIONS

Afatinib plus capecitabine is tolerable but does not have clinically meaningful efficacy in refractory PDA/BTC. Future studies should test novel anti-EGFR/HER2 therapies in KRASWT cancers further selected with a comprehensive molecular profile.

Clinical significance of HER2 overexpression in biliary tract carcinoma --a meta analysis

Introduction

Previous studies have been inconsistent on the correlation of human epidermal growth factor receptor 2 (HER2) overexpression in biliary tract carcinoma. The objective of this meta analysis was to assess its association with clinicopathological features and prognostic significance of biliary tract carcinoma.

Methods

The eligible studies were searched in Pubmed, Embase and Web of Science databases. Inclusion criteria were studies of the relationship between HER2 positive expression (ICH: HER2 (+++), FISH: HER2 overexpression, NGS: HER2 overexpression) and prognosis or clinicopathological features of patients with biliary tract carcinoma (BTC). The analysis was conducted according to gender, high differentiation degree, middle differentiation degree, tumor stage, nerve invasion, vascular invasion, lymph node metastasis and pathological diagnosis of patients. ES (Effect Sizes) for 95% confidence intervals (CI) were calculated to examine risk or hazard associations, and heterogeneity and sensitivity analyses were performed.

Results

A total of 15 studies were included to evaluate the association of HER2 positive expression with clinicopathological features and survival prognosis. There was no significant statistical relationship between positive/high expression of HER2 and a series of clinical characteristics including gender, high, middle and low differentiation, tumor stage, vascular invasion, nerve invasion, Lymph node metastasis, T stage and pathological type of patients with biliary tract carcinoma. There was a significant relationship between positive/high expression of HER2 and postoperative Disease-Free Survival in patients with biliary tract carcinoma (ES = 1.87, 95% CI: 1.24-2.81, p = 0.003). There was a significant relationship between positive/high expression of HER2 and postoperative Overall Survival in patients with biliary tract carcinoma (ES = 1.54, 95% CI: 1.08-2.20, p = 0.017).

Discussion

Our meta-analyses revealed that high expression of HER2 gene was not correlated with clinicopathological parameters such as differentiation degree, TNM stage, lymph node metastasis, vascular invasion, nerve invasion, pathological type, T stage, and gender of biliary tract carcinoma. HER2 overexpression is a negative prognostic factor in biliary tract carcinoma patients. The association between positive/high expression of HER2 and the pathological features as well as prognosis in biliary tract carcinoma patients warrants further validation.

Molecular Testing and Targeted Therapies in Hepatobiliary Cancers: A Review

Importance

Hepatobiliary cancers are heterogeneous and molecularly complex. Recent advances in next-generation sequencing (NGS) have enhanced the understanding of their molecular landscape and enabled deployment of biomarker-based gene- and immune-targeted therapies. This review examines the role of molecular testing and targeted therapies in these malignant neoplasms.

Observations

Patients with hepatobiliary cancers have poor outcomes. Precision oncology studies have shown that while many common molecular alterations are not currently targetable in hepatocellular carcinoma (HCC), a large number of actionable alterations characterize biliary tract cancers (BTCs), with several therapies now approved by the US Food and Drug Administration. Immunotherapy is increasingly adopted in clinical practice, either as monotherapy or combined with cytotoxic chemotherapy, for both HCC and BTCs. Moreover, multiple solid cancer tumor-agnostic therapies are approved (larotrectinib, entrectinib, and repotrectinib for NTRK fusions; selpercatinib for RET fusions; dabrafenib and trametinib combination for BRAF V600E mutations; dostarlimab or pembrolizumab for tumors with high microsatellite instability and pembrolizumab for tumor mutation burden ≥10 mutations/megabase), highlighting the need for NGS as well as ERBB2 (formerly HER2) immunohistochemistry (IHC) (with the recent approval of solid tissue-agnostic deruxtecan trastuzumab for ERBB2-positive [IHC 3+] cancer) across cancers. N-of-1 clinical trials using customized drug combinations matched to the tumor's molecular profile have yielded encouraging results and provide a promising framework for future clinical trial design.

Conclusions and Relevance

Molecular testing and gene- and immune-targeted therapies are transforming hepatobiliary cancer treatment. Tumor-agnostic and N-of-1 clinical trials have challenged traditional clinical trial paradigms and provide the foundation for truly personalized oncology for patients with these aggressive cancers. Further work is needed to determine how to leverage these novel approaches into the management of operable disease.

New frontiers in the pharmacological management of biliary tract carcinomas: the emerging role of drug conjugates

INTRODUCTION

Biliary tract cancer (BTC) is a human malignancy with a poor prognosis. However, significant progress has been made in understanding the molecular mechanisms of carcinogenesis, leading to the development of targeted therapy strategies in recent years. The challenge now is to develop new therapeutic concepts to further increase the efficacy of BTC treatments in the coming years.

AREAS COVERED

This review covers the emerging and advanced approaches of highly sophisticated antibody-drug conjugates (ADCs) and non-ADCs, particularly in relation to BTC. Additionally, the potential advantages and disadvantages of ADCs and non-ADCs regarding toxicities, bioavailability, and efficacy are presented and discussed.

EXPERT OPINION

Given the poor prognosis of BTCs, new targeted and precision therapy strategies using drug conjugates - with and without antibodies as drug carriers - have the potential to overcome the limitations of conventional chemotherapy by improving treatment specificity and efficacy while reducing systemic toxicity. However, several open questions remain regarding ADCs and non-ADCs, including chemical design, drug delivery, related diagnostic and therapeutic biomarkers, and combinatory application strategies.

Zanidatamab: First Approval

Zanidatamab (ZIIHERA®; zanidatamab- hrii), a bi-specific antibody targeting two non-overlapping epitopes of the human epidermal growth factor receptor 2 (HER2) protein, is being developed by Jazz Pharmaceuticals and BeiGene Ltd under license agreements from Zymeworks Inc., the developer of the molecule, for the treatment of HER2-expressing solid tumours. This article summarizes the milestones in the development of zanidatamab leading to this first accelerated approval for use in adults with previously treated, unresectable or metastatic HER2+ (IHC3+) biliary tract cancer (BTC), as detected by an FDA-approved test.

A year in pharmacology: new drugs approved by the US Food and Drug Administration in 2024

The US Food and Drug Administration approved 50 new drugs and nine new cellular and gene therapy products in 2024, i.e., a total of 59 new medical therapies. The latter group represented three treatments each for oncology and hematology/immunotherapy, and one each for neurology, genetic disorders, and cardiovascular disorders. Oncology, hematology/immunotherapy, and neurological disorders (14, six, and seven, respectively) also were highly prevalent among classic medications. Looking at trends over the past 5 years, we observe a greater share in first-in-class medications, more fast-track approvals, and mRNA/gene/cell-based therapies. While small molecules remain the largest fraction, their percentage has been declining substantially over the past 5 years. Taking together, these findings testify to the commitment of the pharmaceutical industry for innovative treatments, including conditions for which no approved therapies existed. On the other hand, there also is a trend for approvals for narrowly focused conditions such as tumors defined by genetic alterations.

EASL Clinical Practice Guidelines on the management of extrahepatic cholangiocarcinoma

Recent years have witnessed significant advances in the imaging, molecular profiling, and systemic treatment of cholangiocarcinoma (CCA). Despite this progress, the early detection, precise classification, and effective management of CCA remain challenging. Owing to recent developments and the significant differences in CCA subtypes, EASL commissioned a panel of experts to draft evidence-based recommendations on the management of extrahepatic CCA, comprising distal and perihilar CCA. Particular attention is given to the need for accurate classification systems, the integration of emerging molecular insights, and practical strategies for diagnosis and treatment that reflect real-world clinical scenarios.

Molecular targeted maintenance therapy versus standard of care in advanced biliary cancer: an international, randomised, controlled, open-label, phase III umbrella trial (SAFIR-ABC10-Precision Medicine)

BACKGROUND

Advanced biliary tract cancers (ABCs) are a heterogeneous group of rare malignancies of the bile ducts and gall-bladder with a poor prognosis and limited treatment options. Cisplatin-gemcitabine (CISGEM) chemotherapy plus immunotherapy (durvalumab or pembrolizumab) is the current first-line standard of care (1L-SoC). ABCs frequently harbour actionable molecular alterations that suggest a high potential for benefit from molecular targeted therapies (MTTs). However, the assessment of potential first-line MTT treatments is hindered by the scarcity of ABCs harbouring a specific alteration and the time required to carry out tumour molecular profiling.

MATERIALS AND METHODS

We detail here the design of SAFIR-ABC10, an international, randomised, phase III umbrella trial comparing the efficacy of sequential matched targeted therapy after four cycles (12 weeks) of 1L-SoC versus continued 1L-SoC in patients with ABC and an actionable molecular alteration [European Society for Medical Oncology (ESMO) Scale for Clinical Actionability of molecular Targets (ESCAT) tier I or II]. The primary study endpoint is progression-free survival. Besides initial tumour and circulating DNA next-generation sequencing analysis, sequential blood and tumour sampling will be carried out to identify biomarkers of prognosis, response and acquired resistance.

PERSPECTIVES

SAFIR-ABC10 is, to our knowledge, the first randomised, umbrella trial assessing the concept of precision medicine in ABC, the ideal setting for addressing this question with a high rate of targetable alterations.

Biomarkers and Management of Cholangiocarcinoma: Unveiling New Horizons for Precision Therapy

Cholangiocarcinoma (CCA) is an aggressive malignancy with limited methods for early detection, necessitating the development of reliable biomarkers for diagnosis and management. However, conventional tumor markers, such as CA19-9 and CEA, exhibit insufficient diagnostic accuracy. Recent advancements in molecular genetics have identified several actionable mutations in CCA, enabling molecularly targeted therapies that improve survival in patients harboring these genetic alterations. Cancer panels, which facilitate multiplex genetic profiling, are critical for identifying these mutations. Studies indicate that several actionable mutations are detected in CCA cases, with patients receiving mutation-guided therapies achieving markedly better outcomes. Liquid biopsies, including cell-free DNA and circulating tumor DNA, offer real-time, non-invasive approaches to monitoring tumor dynamics, heterogeneity, and treatment responses. Furthermore, numerous studies have identified non-coding RNAs in serum and bile as promising biomarkers for the diagnosis and management of CCA. On the other hand, immunotherapy, particularly immune checkpoint inhibitors, has shown efficacy in subsets of CCA patients. However, the success of these therapies is often affected by the status of the tumor immune microenvironment (TME), underscoring the need for comprehensive TME analysis to predict responses to immune checkpoint inhibitors. Despite these advances, no single biomarker currently demonstrates sufficient sensitivity or specificity for clinical application. The integration of multi-omics approaches with cutting-edge technologies holds promise for enhancing diagnostic accuracy, optimizing treatment stratification, and advancing precision medicine in CCA. These developments highlight the transformative potential of biomarkers to improve early detection, prognostic assessment, and personalized therapeutic interventions for CCA.

Characterization and clinical outcomes of rare biliary adenosquamous carcinoma

BACKGROUND

Data are scarce regarding biliary adenosquamous carcinoma (BASC) due to its low incidence. BASC displays a worse prognosis than adenocarcinoma and its specific treatment is still an unmet medical need. We conducted a description analysis of BASC including clinicopathologic parameters and treatment outcomes.

METHODS

All consecutive patients with histologically proven BASC diagnosed in six French hospitals between 2000 and 2022 were enrolled and described.

RESULTS

A total of 16 BASC, accounting for 1.4 % of all biliary tract carcinoma, were included and the BASC incidence increased steadily over the past 22 years. The median age at diagnosis was 70.7 years (min-max 31.4-82.0 years) with most women (62.5 %). At diagnosis, half of BASC patients had a localized stage. The primary tumor locations were shared between gallbladder cancers (n = 7) and cholangiocarcinoma (n = 7), with mainly an extra-hepatic disease (71.4 %). Median overall survival was 9.5 months (95 % CI = 2.1-14.8 months). A total of 13 (81.6 %) patients had undergone surgery with a median relapse-free survival of 3.8 months (95 % CI = 0.0-10.5 months). Five (38.5 %) patients received an adjuvant chemotherapy. A total of seven (43.8 %) patients were treated with chemotherapy for the occurrence of metastases with a median progression-free survival of 2.8 months (95 % CI = 0.8-4.1 months). No objective response was observed and stable disease was achieved in two patients (28.6 %).

CONCLUSIONS

BASC is a rare disease with an increased incidence, highlighting the diagnostic challenges. BASC population was associated with a poor prognostic and limited therapeutic response. Further molecular investigations should be performed to investigate new therapeutic options.

Systemic therapy for pretreated advanced biliary tract cancer: past developments and recent advances

Biliary tract cancer (BTC) remains among the most challenging malignancies with a poor prognosis and limited treatment options, particularly in pretreated patients. As most patients experience disease progression after first-line treatment, effective second-line and subsequent treatments are required. Although the addition of modified FOLFOX (fluorouracil, leucovorin, and oxaliplatin) to active symptom control improved the overall survival of patients with progressing advanced BTC despite gemcitabine plus cisplatin treatment, its efficacy was modest. Moreover, most clinical trials demonstrated modest efficacy of molecular-targeted agents for molecularly unselected pretreated advanced BTC. Patients with advanced BTC carry a relatively high druggable genetic alteration rate and have shown promising responses to molecular-matched therapies targeting gene alterations such as FGFR2 fusions/rearrangements, IDH1 mutation, and HER2 overexpression/amplification. Additionally, tumor-agnostic approaches, including BRAF V600E, NTRK fusion, and RET fusion, have expanded the treatment options for some patients. Immune checkpoint inhibitors have shown limited efficacy as mono- or combination therapy in patients with pretreated advanced BTC. Therefore, developmental efforts have shifted to immune checkpoint inhibitor and other combinations such as vascular endothelial growth factor receptor inhibitors or radiation. In addition to refining combination strategies to enhance the therapeutic potential of immune checkpoint inhibitor, future research should focus on elucidating the tumor microenvironment. This review delineates the evolution of systemic therapies in patients with pretreated advanced BTC. By examining past developments and recent advances through prospective trials, it highlights novel approaches that may improve outcomes in this challenging disease.

Clinicomolecular Profile and Efficacy of Human Epidermal Growth Factor Receptor 2 (HER2)-Targeted Therapy for HER2-Amplified Advanced Biliary Tract Cancer

PURPOSE

This study aimed to investigate the clinicomolecular profiles and the efficacy of human epidermal growth factor receptor 2 (HER2)-targeted therapy in HER2-amplified biliary tract cancer (BTC).

METHODS

This study was an international collaboration that used combined data from the prospective SCRUM-Japan GOZILA and MONSTAR-SCREEN in Japan and retrospective reviews in the United States; patients with advanced BTC who had received systemic therapy were included. The clinicomolecular profiles were evaluated in an exploratory cohort, whereas the efficacy of HER2-targeted therapy was assessed in a biomarker-selected cohort.

RESULTS

Of the 439 patients in the exploratory cohort, 43 (10%) had HER2 amplification. The frequencies of coalterations were higher in patients with HER2 amplification versus patients without HER2 amplification including HER2 mutations (26% v 5%, P < .001), TP53 mutations (84% v 61%, P = .003), and BRAF amplification (9% v 2%, P = .030). There were no KRAS mutations identified in patients with HER2-amplified BTC. No significant difference in overall survival (OS) was observed between patients with and without HER2 amplification (median, 17.7 v 16.9 months; hazard ratio [HR], 0.95 [95% CI, 0.65 to 1.40]). Of the 60 patients with HER2-amplified BTC in the biomarker-selected cohort (43 from Japan and 17 from the United States), the OS was significantly longer in 29 patients who received HER2-targeted therapy than in those who did not receive HER2-targeted therapy (median, 24.3 v 12.1 months; HR, 0.39 [95% CI, 0.23 to 0.82]). Multivariate analysis identified HER2-targeted therapy as an independent prognostic factor for OS (HR, 0.29 [95% CI, 0.14 to 0.58]; P < .001).

CONCLUSION

HER2 amplification was found in 10% of advanced BTC and was not identified as an independent prognostic factor for OS. Patients with HER2-amplified BTC derive significant benefit from HER2-targeted therapy.

Evolving Landscape of HER2-Targeted Therapies for Gastric Cancer Patients

OPINION STATEMENT

Gastric cancer (GC) is a deadly disease worldwide, and trastuzumab in combination with chemotherapy has been the standard first-line treatment for HER2-positive GC following the TOGA trial. Besides adjuvant therapy, HER2-directed therapy is widely used as neoadjuvant or translational therapy, and survival benefit even surgical opportunities is seen in these patients. However, resistance is not rare in recent years, and the second-line treatment for trastuzumab beyond progression has received widespread attention in GC. Moreover, current evidence cannot recommend trastuzumab for patients with IHC1+ HER2 low expression GC yet. Researchers are currently investigating whether GC patients with low HER2 expression could also benefit from HER2-directed therapies. In addition to using HER2 as a target for targeted therapy, HER2-mediated targeted delivery of cytotoxic drugs and targeted immunity have made important contributions to overcoming trastuzumab resistance in recent trials. HER2/neu-derived peptide epitopes vaccination and HER2-specific chimeric antigen receptor (CAR) therapy focus on reestablishing anti-tumor immunity in different ways and show significant anti-tumor activity. Other antibodies that target different regions of the HER2 receptor or block key downstream pathways such as AKT or PI3K also offer potential anti-tumor activity against HER2. HER2 use in GC will not be hampered by resistance or low expression and will play a bigger role. We review the current efforts to enable GC patients with trastuzumab-resistant and HER2 low-expressing accessible to HER2 targeted therapy and present our consideration for future HER2 in GC.

HER2-targeted therapies: Unraveling their role in biliary tract cancers

Biliary tract cancers (BTCs) constitute a heterogeneous group of malignancies with rising incidence and limited therapeutic options in advanced stages, leading to increased overall mortality. Extensive genomic profiling has identified key oncogenic drivers in BTCs that represent promising therapeutic targets and could change the treatment paradigm. Evidence suggests improved survival outcomes for patients with actionable molecular alterations who received matched targeted therapies. Human epidermal growth factor receptor 2 (HER2) is a receptor tyrosine kinase and proto-oncogene that has been extensively studied as a prognostic biomarker and a therapeutic target in multiple solid organ malignancies. Recent clinical trials on the combination of trastuzumab with tucatinib, FOLFOX, or pertuzumab for previously treated, HER2-positive, advanced BTCs have shown improved outcomes compared to current second-line therapies. Early evidence from observational studies on trastuzumab-containing regimens as first-line suggests promising efficacy. Furthermore, the recent tumor-agnostic approval of trastuzumab deruxtecan for HER2-positive solid tumors has formally introduced HER2-directed agents in the BTC therapeutic arsenal. This review aims to summarize the rapidly evolving landscape of HER2-directed agents for BTCs, highlighting current evidence of survival benefit. Beginning with a concise presentation of the structural and functional aspects of HER2, we detail the frequency and prognostic significance of HER2 alterations in BTCs and discuss all available preclinical and clinical data on anti-HER2 agents tested for BTCs.

Safety and Efficacy of Anti-Human Epidermal Growth Factor 2 Agents in the Treatment of Biliary Tract Cancers: A Systematic Review

PURPOSE

Limited treatment options exist for patients with locally advanced or metastatic biliary tract cancers (BTCs). Recently, several clinical trials provided preliminary evidence for human epidermal growth factor receptor 2 (HER2) as a new target for patients with HER2-expressing BTC. We conducted a systematic review and pooled analysis of the safety and efficacy of anti-HER2 agents in patients with advanced BTCs.

METHODS

A comprehensive search of PubMed/MEDLINE and EMBASE was performed to identify phase I, II, or III clinical trials published between January 2019 and March 2024 that evaluated anti-HER2 therapy in locally advanced or metastatic BTC. Participant data included in the analysis were from trials evaluating the efficacy and safety of various anti-HER2 agents. The primary end points included objective response rate (ORR), disease control rate (DCR), and progression-free survival (PFS). The secondary end points included incidence of treatment-related adverse events (TRAEs), rate of treatment discontinuation, and death.

RESULTS

The analysis included 368 patients from eight publications diagnosed with advanced BTC. Patients were treated with several anti-HER2 agents including zanidatamab, pertuzumab plus trastuzumab, tucatinib plus trastuzumab, trastuzumab deruxtecan, trastuzumab plus chemotherapy, trastuzumab-pkrb plus chemotherapy, and neratinib. The pooled ORR and DCR were 34% (95% CI, 24 to 44) and 64% (95% CI, 51 to 77), respectively. The pooled weighted PFS and median overall survival were 4.8 and 9.4 months, respectively. The pooled duration of response for the reporting trials was 5.0 months. In the study cohort, 82.6% of patients experienced any adverse event and 32.1% experienced a grade 3-4 adverse event. Only 5.7% of the patients discontinued treatment secondary to TRAEs.

CONCLUSION

In patients with HER2-expressing BTCs, anti-HER2 therapies are viable options, particularly in the second-line setting.

Novel drugs approved by the EMA, the FDA and the MHRA in 2024: A year in review

In the past year, the European Medicines Agency (EMA), the Food and Drug Administration (FDA) and the Medicines and Healthcare Products Regulatory Agency (MHRA) authorised 53 novel drugs. While the 2024 harvest is not as rich as in 2023, when 70 new chemical entities were approved, the number of 'orphan' drug authorisations in 2024 (21) is similar to that of 2023 (24), illustrating the dynamic development of therapeutics in areas of unmet need. The 2024 approvals of novel protein therapeutics (15) and advanced therapy medicinal products (ATMPs, 6) indicate a sustained trend also noticeable in the 2023 new drugs reviewed in this journal last year (16 and 11, respectively). Clearly, the most striking characteristic of the 2024 drug yield is the creative pharmacological design, which allows these medicines to employ a novel approach to target a disease. Some notable examples are the first drug successfully using a 'dock-and-block' mechanism of inhibition (zenocutuzumab), the first approved drug for schizophrenia designed as an agonist of M1/M4 muscarinic receptors (xanomeline), the first biparatopic antibody (zanidatamab), binding two distinct epitopes of the same molecule, the first haemophilia therapy that instead of relying on external supplementation of clotting factors, restores Factor Xa activity by inhibiting TFPI (marstacimab), or the first ever authorised direct telomerase inhibitor (imetelstat) that reprogrammes the oncogenic drive of tumour cells. In addition, an impressive percentage of novel drugs were first in class (28 out of 53 or 53% of the total) and a substantial number can be considered disease agnostic, indicating the possibility of future approved extensions of their use for additional indications. The 2024 harvest demonstrates the therapeutic potential of innovative pharmacological design, which allows the effective targeting of intractable disorders and addresses crucial, unmet therapeutic needs.

Current status and prospects of targeted therapy for cholangiocarcinoma based on molecular characteristics

Cholangiocarcinoma (CCA) is a serious public health issue due to its insidious onset and dismal prognosis. The past few years have witnessed and highlighted the development of understanding and management of CCA. The combination of gemcitabine and cisplatin (GP) chemotherapy regimen with immunotherapy using immune checkpoint inhibitors has been considered the new standard first-line treatment alternative for advanced CCA. Notably, the proportion of patients with advanced CCA with targetable genetic mutations is approximately 40 %, and these patients may be considered for molecularly targeted therapy in the second-line treatment. In this review, we highlight the advances and progress in targeted therapies for advanced CCA, with special attention to data from Asian populations, including Chinese. In addition, we present in detail the phosphatase tension homolog (PTEN), a novel biomarker for both of first-line chemotherapy and second-line targeted therapy in advanced CCA, and its ability to forecast prognosis in patients with CCA. The mechanisms of rapid resistance to targeted agents warrant further investigation and address in light of the development of new targeted therapies. Precision medicine is gradually playing an increasing role in achieving optimal therapeutic outcomes.

Leveraging HER2-targeted biparatopic antibodies in solid tumors

Biparatopic antibodies (bpAbs), which target non-overlapping epitopes on the same antigen, offer unique mechanisms of action and therapeutic applications that surpass those of conventional monospecific antibodies. These distinctive properties have positioned bpAbs as effective therapeutic agents in the treatment of cancer and infectious diseases, especially in cases where current treatments face limitations. Among these, HER2-targeted bpAbs have shown significant improvements in survival outcomes for patients with solid tumors that depend on HER2 signaling. However, a comprehensive understanding of their clinical impact, mechanisms of action, and limitations in therapeutic use remains lacking. Here, we review and contrast the clinical performance of the well-established HER2-targeted bpAbs in current use, with a focus on their mechanisms of action, associated limitations, and potential combination strategies. We also highlight emerging investigational bpAbs-based agents that have shown promise in the treatment of HER2-positive solid cancers. These advancements may lead to enhanced therapeutic options and potentially broaden the scope of bpAbs in cancer therapy.

Update for: New developments in systemic therapy for advanced biliary tract cancer

Biliary tract cancer, carcinoma of the extrahepatic bile ducts, carcinoma of the gallbladder, ampullary carcinoma, and intrahepatic cholangiocarcinoma are often identified at advanced stages. The standard therapy for advanced biliary tract cancer has been a combination of cytotoxic agents. Globally, gemcitabine plus cisplatin has been the standard first-line regimen, whereas gemcitabine plus cisplatin plus S-1 and gemcitabine plus S-1 have also been the standard regimens in Japan. Recently, treatment strategies have been updated. As first-line systemic therapy, the addition of an immune checkpoint inhibitor, such as durvalumab or pembrolizumab, to gemcitabine plus cisplatin has been shown to prolong overall survival compared with gemcitabine plus cisplatin. These combined immunotherapies are widely used in clinical practice as internationally standard first-line regimens. Regarding second-line treatment after a gemcitabine-based regimen, fluorouracil and folinic acid plus oxaliplatin have been the standard regimen. Additionally, FGFR2 fusion gene/rearrangement, mutations of IDH1/2, KRAS, and BRAF, and overexpression of HER2 are promising therapeutic targets for which the effectiveness of each targeted therapy has been reported, at this time, as a second-line or later treatment.

Tucatinib in the treatment of HER2-overexpressing gastrointestinal cancers: current insights and future prospects

INTRODUCTION

Over the past 20 years, the treatment landscape of HER2-amplified tumors has considerably evolved. Until now, no approved targeted therapies were available for patients with HER2-amplified metastatic colorectal cancer (mCRC). Tucatinib, a highly selective tyrosine kinase inhibitor, demonstrated significant efficacy in combination with trastuzumab in patients with refractory mCRC, leading to its approval by the Food and Drug Administration (FDA).

AREAS COVERED

This review dives into the efficacy of tucatinib-based regimens in gastrointestinal malignancies, with a focus on the pivotal MOUNTAINEER trial, which led to the FDA approval of tucatinib plus trastuzumab in chemo-refractory HER2-amplified mCRC. Additionally, ongoing trials are exploring tucatinib in earlier treatment lines and across other gastrointestinal cancers, including biliary tract, gastric, and pancreatic malignancies. The mechanistic basis of dual HER2 inhibition and its implications for clinical practice are discussed.

EXPERT COMMENTARY

The future of tucatinib-based therapeutic strategies in GI malignancies depends on their integration into different treatment lines. Addressing acquired resistance using liquid biopsy-guided strategies and other TKIs like lapatinib will be paramount to improve outcomes.

Safety of current treatments for advanced cholangiocarcinoma

INTRODUCTION

Biliary tract cancer (BTC) originates from the biliary epithelium of the small ducts within the liver (intrahepatic cholangiocarcinoma, IHCC), the main ducts of the hilum (extrahepatic cholangiocarcinoma, EHCC), or in the gallbladder (gallbladder cancer, GC). Due to presentation with nonspecific symptoms as well as absence of screening, most patients present with advanced disease and unfavorable prognosis.

AREAS COVERED

The ABC-02 trial established the current first-line chemotherapy with gemcitabine/platinum for advanced BTC in 2010. Since then, multiple therapies have become available exploring different targetable alterations, emphasizing the importance of molecular profiling in all patients with BTC as well as understanding the distinct toxicity profile associated with these therapies. Besides chemotherapy, immunotherapy as well as targeted therapies for FGFR2, IDH1, and HER2 will be discussed in this manuscript. We performed a non-systematic review, largely based on high-quality articles on the topic of interest with no predefined protocol.

EXPERT OPINION

The primary objective of this manuscript is to conduct a thorough review of diverse aspects related to the safety of systemic treatment in BTC. As the benefit of these therapies depends on compliance and/or tolerance, the authors aim to discuss different toxicity profiles and to provide insights into strategies for overcoming them.

New systemic treatment paradigms in advanced biliary tract cancer and variations in patient access across Europe

In recent years, treatment options for patients with advanced biliary tract cancer (BTC) have increased significantly due to the positive results from phase 2/3 clinical trials of immune checkpoint inhibitors, combined with chemotherapy, and molecularly targeted agents. These advances have led to the need for molecular testing to identify actionable alterations and patients amenable to targeted therapies. However, these improvements have brought with them many questions and challenges, including the identification of resistance mechanisms and therapeutic sequences. In this Series paper we aim to provide an overview of the current systemic treatment options for patients with BTC, highlighting disparities in access to innovative treatments and molecular testing across European countries, which lead to inequalities in the possibilities of treating patients with advanced BTC. We also discuss how ongoing European collaborative projects, such as the COST Action Precision-BTC-Network CA22125, supported by COST (European Cooperation in Science and Technology), linked to the European Network for the Study of Cholangiocarcinoma (ENSCCA), can help overcome these disparities and improve the current scenario.

Recent 5‑year trends in biliary tract cancer survival rates: An analytical big data survey

Biliary tract cancer (BTC), also known as cholangiocarcinoma, is a relatively rare type of cancer with a poor prognosis. Despite the combination of chemotherapy and advances in targeted therapy, which have potentially improved the prognosis of patients with BTC, research on outcomes remains inadequate. The present study thus analyzed the survival trends of patients with BTC. The present study used anonymized data from a public national database and focused on 13,600 individuals diagnosed with BTC between 2015 and 2020. The overall and 1-year mortality rates were analyzed according to cancer anatomic sites, along with the impact of comorbidities, such as diabetes and hepatitis on these rates. A total of 13,600 patients were included in the analysis; 26.31% of the patients had intrahepatic BTC, 27.46% had extrahepatic BTC and 46.24% had gallbladder (GB) cancer. For all BTC types, the 1-year survival hazard ratio (HR) in 2018 was 0.992 compared with that in 2015, and 0.986 in 2019. Compared with intrahepatic BTC, the 1-year survival rate was 0.349 for GB cancer and 0.641 for extrahepatic BTC. Patients with diabetes had an HR of 1.318 compared with those without diabetes. For patients with BTC previously diagnosed with GB stones, the survival HR was 0.902, compared to those without GB stones. On the whole, the analysis of national healthcare big data indicated an improvement in the overall prognosis of patients with BTC from 2018. Moreover, these data highlight that the prognosis of patients with BTC is influenced by the anatomical location of the cancer, and that co-existing medical conditions in patients affect the survival rate.

HER2 Pathway in Biliary Tract Cancer: A Snapshot of the Current Understanding and Future Directions

Biliary tract cancers (BTCs) are a wide class of malignancies with dismal prognosis. The therapeutic scenario of metastatic BTCs has profoundly changed during recent years. The combination of cisplatin-gemcitabine plus immunotherapy is currently the gold standard in the first line. The more extensive comprehension of the mechanisms at the basis of BTCs and the identification of several molecular alterations has led to the introduction of target-directed therapies in the second line and beyond that have expanded the therapeutic armamentarium alongside the standard FOLFOX regimen, and for the near future, the results of some trials with targeted therapies in first line are expected. HER2 represents a promising therapeutic target detected in BTCs, being overexpressed in approximately 15-20% of cases, with a strong predilection for gallbladder carcinoma and extrahepatic cholangiocarcinoma, although a small proportion of HER2 overexpression can be detected even in intrahepatic cholangiocarcinoma. The efficacy and safety of different HER2 inhibitors have been investigated in several studies in the second line and beyond with encouraging results. This comprehensive review is intended to provide a summary of existing evidence and future perspectives on HER2 altered BTCs.

Cholangiocarcinoma Targeted Therapies: Mechanisms of Action and Resistance

Cholangiocarcinoma is an aggressive bile duct malignancy with heterogeneous genomic features. Although most patients receive standard-of-care chemotherapy/immunotherapy, genomic changes that can be targeted with established or emerging therapeutics are common. Accordingly, precision medicine strategies are transforming the next-line treatment for patient subsets. Hotspot IDH1 mutations and activating fibroblast growth factor receptor 2 fusions occur frequently, and small-molecule inhibitors against these alterations are US Food and Drug Administration approved. Translational and basic science studies have elucidated the mechanisms of response and resistance in cholangiocarcinoma, providing insights into these targets that extend to other cancers. Additional US Food and Drug Administration-approved and National Comprehensive Cancer Network guideline-recommended treatments for recurrent genomic changes include BRAF inhibition (BRAF-V600E) and trastumazab deruxtecan (human epidermal growth factor receptor 2 amplification). Furthermore, ongoing clinical trials show promising results with KRAS inhibition (KRAS-codon 12 mutations), PRTM5 inhibition, alone or with methylthioadenosine inhibition (5-methylthioadenosine phosphorylase deletion), and murine double minute 2 inhibition (murine double minute 2 amplification). Despite these advances, the rate, depth, and duration of response to each treatment need improvement. Moreover, many patients do not have currently targetable genotypes. This review examines the clinical efficacy and mechanisms of resistance associated with these treatments, as well as insights into the molecular and biological effects of pathway activation and inhibition, based on study of patient samples and preclinical models. It also explores strategies to overcome resistance and possible precision medicine approaches for additional patient subsets.

Advancing biliary tract malignancy treatment: emerging frontiers in cell-based therapies

Biliary tract malignancies, including intrahepatic cholangiocarcinoma, extrahepatic cholangiocarcinoma, and gallbladder cancer, represent a group of aggressive cancers with poor prognosis due to late-stage diagnosis, limited treatment options, and resistance to conventional therapies like chemotherapy and radiotherapy. These challenges emphasize the urgent need for innovative therapeutic approaches. In recent years, cell-based therapies have emerged as a promising avenue, offering potential solutions through immune modulation, genetic engineering, and targeted intervention in the tumor microenvironment. This Mini-review provides an overview of current advancements in cell-based therapies for biliary malignancies, encompassing immune cell-based strategies such as CAR-T cells, NK cells, dendritic cell vaccines, and tumor-infiltrating lymphocytes. We also examine strategies to overcome the immunosuppressive tumor microenvironment and discuss the integration of cell therapies into multimodal treatment regimens. By synthesizing preclinical and clinical findings, this review highlights key insights and future directions, aiming to assist researchers and clinicians in translating these approaches into effective treatments. The transformative potential of cell-based therapies discussed here makes this review a valuable resource for advancing biliary malignancy research and clinical applications.

Finding the Right Partner: Triplet Therapy for First-Line Advanced Biliary Tract Cancers

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors' suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice.

Advances in Antibody-Based Immune-Stimulating Drugs: Driving Innovation in Cancer Therapy

Antibody-based immune-stimulating drugs (ABIs) represent a transformative frontier in cancer immunotherapy, designed to reshape the tumor microenvironment and overcome immune suppression. This study highlighted recent advances in ABIs, including immune-stimulating antibody conjugates (ISACs), bispecific antibodies (BsAbs), and checkpoint blockade enhancers, with a focus on their mechanisms of action, clinical advancements, and challenges. Preclinical findings revealed that ISACs effectively boost overall anti-cancer immunity by reprogramming tumor-associated macrophages, enhancing T cell activation, and engaging other immune pathways. Similarly, BsAbs effectively redirect immune cells to tumors, achieving significant tumor regression. Additionally, artificial intelligence (AI) is revolutionizing the development of ABIs by optimizing drug design, identifying novel targets, and accelerating preclinical validation, enabling personalized therapeutic strategies. Despite these advancements, significant challenges remain, including immune resistance and off-target effects. Future research should prioritize next-generation multifunctional antibodies, AI-driven innovations, and combination therapies to enhance efficacy and expand therapeutic applications. Connecting these gaps could unlock the full potential of ABIs, upgrading cancer treatment and improving outcomes for patients with refractory or resistant tumors.

Recent progress in emerging molecular targeted therapies for intrahepatic cholangiocarcinoma

Cholangiocarcinoma (CCA) is a diverse group of epithelial malignant tumors arising from the biliary tract, characterized by high molecular heterogeneity. It is classified into intrahepatic (iCCA) and extrahepatic CCA (eCCA) based on the location of the primary tumor. CCA accounts for approximately 15% of all primary liver cancers, with iCCA comprising 10-20% of all CCAs. iCCA is especially known for its characteristic aggressiveness and refractoriness, leading to poor prognosis. Despite the increasing global incidence and mortality rates, surgery remains the only available standard treatment approach for a subset (25%) of patients with early-stage, resectable iCCA. The paucity of effective systemic medical therapies restricts therapeutic options for patients with advanced or metastatic iCCA. In the past decade, advances in the understanding of the molecular complexity of these tumors have provided fruitful insights for the identification of promising new druggable targets and the development of feasible therapeutic strategies that may improve treatment outcomes for patients with iCCA. In this review, we aim to highlight critical up-to-date studies and medicinal chemistry aspects, focusing on novel targeted approaches utilizing promising candidates for molecular targeted therapy in iCCA. These candidates include aberrations in isocitrate dehydrogenase (IDH) 1/2, fibroblast growth factor receptor (FGFR), B-Raf proto-oncogene (BRAF), neurotrophic tyrosine receptor kinase (NTRK), human epidermal growth factor receptor 2 (HER2), and programmed cell death protein 1 (PD-1)/programmed cell death-ligand 1 (PD-L1). Furthermore, this review provides an overview of potential inhibitors aimed at overcoming acquired drug resistance in these actionable targets for iCCA.

Clinicopathologic and genomic characteristics of biliary tract carcinomas with TERT promoter mutations among East Asian population

Telomerase reverse transcriptase gene promoter (TERT) mutations are biomarkers that predict survival and responses to immune checkpoint inhibitors in various malignancies. However, their prevalence and clinicopathologic characteristics in biliary tract carcinomas are largely unknown. We performed a comprehensive genomic profiling of formalin-fixed paraffin-embedded tumor tissue from 485 carcinomas, including intrahepatic (n = 220), perihilar (n = 54), distal biliary tract (n = 110), and gallbladder (n = 101) cancers, using next-generation sequencing. TERT mutations were observed in 50 out of 485 biliary tract cancers (10.3 %) consisting of 39 C228T (78.0 %) and 11 C250T (22.0 %) variants. Among the different anatomic locations, TERT mutations were most frequent in the gallbladder (20.8 %), followed by perihilar (9.3 %), intrahepatic (7.7 %), and distal bile ducts (6.4 %) (p < 0.01). Genetically, TERT mutations were significantly associated with TP53 mutations (p = 0.04), ERBB2 amplification (p < 0.01), and high tumor mutational burdens (TMB) (p < 0.01); moreover, they were negatively correlated with KRAS (p < 0.01), SMAD4 (p = 0.01), and PBRM1 mutations (p = 0.01). In addition, TERT mutations were associated with a poor progression-free survival (PFS, p = 0.01). Specifically, in cases of intrahepatic cholangiocarcinoma, TERT mutations were more frequent in patients with cirrhosis (p = 0.01), hepatitis B virus infection (p = 0.04), and advanced disease stages (p < 0.01). In gallbladder carcinoma, TERT mutations were also associated with poor PFS. In conclusion, TERT mutations in biliary tract carcinomas had unique clinicopathologic and genetic characteristics. Despite its poor PFS, the concomitant presence of ERBB2 amplification and a high TMB indicated a potential for targeted therapy and immunotherapy in this specific subtype.

Molecular biology of cholangiocarcinoma and its implications for targeted therapy in patient management

Cholangiocarcinoma (CCA) remains a devastating malignancy and a significant challenge to treat. The majority of CCA patients are diagnosed at an advanced stage, making the disease incurable in most cases. The advent of high-throughput genetic sequencing has significantly improved our understanding of the molecular biology underpinning cancer. The identification of 'druggable' genetic aberrations and the development of novel targeted therapies against them is opening up new treatment strategies. Currently, 3 targeted therapies are approved for use in CCA; Ivosidenib in patients with IDH1 mutations and Infigratinib/Pemigatinib in those with FGFR2 fusions. As our understanding of the biology underpinning CCA continues to improve it is highly likely that additional targeted therapies will become available in the near future. This is important, as it is thought up to 40 % of CCA patients harbour a potentially actionable mutation. In this review we provide an overview of the molecular pathogenesis of CCA and highlight currently available and potential future targeted treatments.

Prodrug-based bispecific antibodies for cancer therapy: advances and future directions

Bispecific antibodies represent an innovative paradigm in cancer therapy, offering broader therapeutic potential compared to conventional monoclonal antibodies. To increase tumor selectivity while mitigating off-target effects in normal tissues, the concept of prodrug-based bispecific antibodies has emerged. This review delineates the various mechanisms underlying the action of prodrug-based bispecific antibodies, including protease-mediated activation, steric hindrance release via proteolytic processing, activation by soluble factors, conditional assembly, and chain exchange-mediated activation. We also address the critical challenges that must be overcome to optimize the development and clinical application of these sophisticated therapeutic agents.

A First-in-Human Study of Cinrebafusp Alfa, a HER2/4-1BB Bispecific Molecule, in Patients with HER2-Positive Advanced Solid Malignancies

PURPOSE

4-1BB (CD137) is a costimulatory immune receptor expressed on activated T cells, activated B cells, NK cells, and tumor-infiltrating lymphocytes, making it a promising target for cancer immunotherapy. Cinrebafusp alfa, a monoclonal antibody-like bispecific protein targeting HER2 and 4-1BB, aims to localize 4-1BB activation to HER2-positive tumors. This study evaluated the safety, tolerability, and preliminary efficacy of cinrebafusp alfa in patients with previously treated HER2-positive malignancies.

PATIENTS AND METHODS

This was a multicenter dose-escalation study involving patients with HER2-positive malignancies who received prior treatment. The study assessed the safety and efficacy of cinrebafusp alfa across various dose levels. Patients were assigned to different cohorts, and antitumor responses were evaluated. The study aimed to determine the MTD and to observe any clinical activity at different dose levels.

RESULTS

Of 40 evaluable patients in the "active dose" efficacy cohorts, five showed an antitumor response, resulting in an overall response rate of 12.5% and a disease-control rate of 52.5%. Clinical activity was observed at the 8 and 18 mg/kg dose levels, with confirmed objective response rates of 28.6% and 25.0%, respectively. Cinrebafusp alfa was safe and tolerable, with grade ≤2 infusion-related reactions being the most frequent treatment-related adverse event. MTD was not reached during the study.

CONCLUSIONS

Cinrebafusp alfa demonstrates promising activity in patients with HER2-positive malignancies who have progressed on prior HER2-targeting regimens. Its acceptable safety profile suggests it could be a treatment option for patients not responding to existing HER2-directed therapies. See related commentary by Eguren-Santamaría et al., p. 231.

Utilizing Patient-Derived Xenografts to Model Precision Oncology for Biliary Tract Cancer

PURPOSE

Biliary tract cancers, which are rare and aggressive malignancies, are rich in clinically actionable molecular alterations. A major challenge in the field is the paucity of clinically relevant biliary tract cancer models that recapitulate the diverse molecular profiles of these tumors. The purpose of this study was to curate a collection of patient-derived xenograft (PDX) models that reflect the spectrum of genomic alterations present in biliary tract cancers to create a resource for modeling precision oncology.

EXPERIMENTAL DESIGN

PDXs were derived from biliary tract cancer samples collected from surgical resections or metastatic biopsies. Alterations present in the PDXs were identified by whole-exome sequencing and RNA sequencing. PDXs were treated with approved and investigational agents. Efficacy was assessed by change in tumor volume from baseline. Event-free survival was defined as the time to tumor doubling from baseline. Responses were categorized at day 21: >30% decrease in tumor volume = partial response, >20% increase in tumor volume = progressive disease, and any non-partial response/progressive disease was considered stable disease.

RESULTS

Genomic sequencing demonstrated key actionable alterations across this cohort, including alterations in FGFR2, isocitrate dehydrogenase I, ERRB2, PIK3CA, PTEN, and KRAS. RNA sequencing demonstrated fusions and expression of antibody-drug conjugate targets, including TROP2, HER2, and Nectin4. Therapeutic matching revealed objective responses to approved and investigational agents that have been shown to have antitumor activity clinically.

CONCLUSIONS

In this study, we developed a catalog of biliary tract cancer PDXs that underwent comprehensive molecular profiling and therapeutic modeling. To date, this is one of the largest collections of biliary tract cancer PDX models and will facilitate the development of personalized treatments for patients with these aggressive malignancies.

Digestive cancers: mechanisms, therapeutics and management

Cancers of the digestive system are major contributors to global cancer-associated morbidity and mortality, accounting for 35% of annual cases of cancer deaths. The etiologies, molecular features, and therapeutic management of these cancer entities are highly heterogeneous and complex. Over the last decade, genomic and functional studies have provided unprecedented insights into the biology of digestive cancers, identifying genetic drivers of tumor progression and key interaction points of tumor cells with the immune system. This knowledge is continuously translated into novel treatment concepts and targets, which are dynamically reshaping the therapeutic landscape of these tumors. In this review, we provide a concise overview of the etiology and molecular pathology of the six most common cancers of the digestive system, including esophageal, gastric, biliary tract, pancreatic, hepatocellular, and colorectal cancers. We comprehensively describe the current stage-dependent pharmacological management of these malignancies, including chemo-, targeted, and immunotherapy. For each cancer entity, we provide an overview of recent therapeutic advancements and research progress. Finally, we describe how novel insights into tumor heterogeneity and immune evasion deepen our understanding of therapy resistance and provide an outlook on innovative therapeutic strategies that will shape the future management of digestive cancers, including CAR-T cell therapy, novel antibody-drug conjugates and targeted therapies.

Molecular Profiling of Biliary Tract Cancers in African American and Caucasian Patients

PURPOSE

Biliary tract cancers (BTCs) include intrahepatic cholangiocarcinoma (ICC), extrahepatic cholangiocarcinoma (ECC), and gallbladder cancers. BTCs have a number of genomic alterations, including isocitrate dehydrogenase 1 (IDH1) mutations, fibroblast growth factor receptor 2 (FGFR2) rearrangements, and ERBB2 amplifications. Therapies targeting these alterations have shown clinical benefit in patients with BTCs in the United States. However, molecular differences between races in BTCs are largely unknown. In particular, the genomic profiles of African American (AA) patients with BTCs have been infrequently reported. We sought to identify key genomic differences between AA and Caucasian patients with BTCs in the United States in the Foundation Medicine and American Association for Cancer Research (AACR) GENIE databases.

METHODS

BTC patients from AA and Caucasian patients from the Foundation Medicine and AACR GENIE databases were retrospectively reviewed. BTCs were divided into ICC, ECC, and GBCs in the Foundation Medicine database. BTCs were divided into cholangiocarcinomas and GBCs in the AACR GENIE database.

RESULTS

The mean age of AA patients with BTCs was lower compared with Caucasians. TP53 and FGFR2 alterations were significantly more frequent in AA patients compared with Caucasian patients with BTCs. IDH1 mutations in Caucasian patients with BTCs were double that of AA patients.

CONCLUSION

The results of this study suggest that significant genomic differences exist between races and warrant further investigation.

ESMO Clinical Practice Guideline interim update on the management of biliary tract cancer

•This ESMO Clinical Practice Guideline update addresses new developments in the management of biliary tract cancer. •Recommendations are given for first-line treatment with immune checkpoint inhibitors. •Key recommendations are also provided for second-line treatment with targeted therapies. •The update also covers the latest developments in molecular testing and intra-arterial therapies. •A management algorithm for early-stage, locally advanced and advanced/metastatic disease is provided.

Systemic approaches in biliary tract cancers: a review in the era of multidirectional precision medicine

INTRODUCTION

Despite a rising incidence, biliary tract cancers (BTCs) are still considered a rare tumor entity. The disease's subtle clinical presentation and lack of effective early detection strategies often lead to a diagnosis at an advanced or unresectable stage, where curative options are limited.

AREAS COVERED

This review provides an overview of current systemic therapies and emerging novel approaches for BTC. For decades, the combination of gemcitabine with cisplatin (GemCis) has been the standard of care for palliative treatment. However, since 2020, the diagnostic and therapeutic landscape for BTC has evolved considerably, not only in the first-line setting but also beyond, driven by the development of clinical trials exploring immunotherapy and molecularly targeted agents. Due to the high frequency of targetable genetic alterations in BTC patients, there is a growing emphasis on obtaining tissue or liquid biopsy samples to identify markers like microsatellite instability and other actionable oncogenic driver genes.

EXPERT OPINION

Early initiation of systemic therapies in combination with multimodal approaches is essential for maximizing survival outcomes in patients with BTC.

Optimizing outcomes and personalizing care with targeted agents in advanced cholangiocarcinoma

Traditional chemotherapy and immunotherapy-based systemic treatments for locally advanced or metastatic cholangiocarcinoma have been associated with poor clinical outcomes driven partly by molecular heterogeneity promoting early treatment resistance and a higher toxicity profile associated with these regimens. Few patients are eligible for upfront surgical resection and clinical studies have been traditionally difficult to conduct due to the orphan nature of this disease. However, increasing use of genomic profiling in clinical practice have led to active investigations of aberrant albeit promising mechanistic therapeutic targets such as IDH-1, FGFRs, BRAFV600E, HER-2 and NTRK. This review article aims to highlight the complex genomic landscape of this difficult-to-treat disease, followed by a discussion of evidence-based biological mechanisms that can be actioned using targeted agents. We explore the clinical rationale behind a targeted therapeutic strategy, the role of liquid biopsies in guiding clinical decisions and future treatment pathways for cholangiocarcinoma management. We also discuss the challenges and opportunities originating from recent clinical trials evaluating targeted treatments and our own institutional experience at UCLH that have aimed to address some of these biological complexities and have translated into improved patient outcomes via effective molecularly driven patient selection strategies. We also provide perspectives on emerging novel, next generation targeted inhibitors overcoming treatment resistance to previous targeted agents with demonstrated clinical value in a challenging patient population.

Chinese expert consensus on the clinical application of molecular diagnostics in hepatobiliary cancers (2024 edition)

Hepatocellular carcinoma (HCC) and biliary tract cancer (BTC) are significant health challenges in China because of their high prevalence and mortality rates. Advances in molecular diagnostics have opened new avenues for personalized treatment strategies. This consensus provides a comprehensive update on the clinical applications of molecular diagnostics in HCC and BTC and addresses the urgent need for personalized treatment strategies tailored to the Chinese population, emphasizing the importance of molecular markers in guiding targeted therapies and immunotherapies. By employing the Delphi method and the Grading of Recommendations Assessment, Development, and Evaluation system, the expert panel formulated evidence-based recommendations for the use of molecular diagnostics in the clinical management of HCC and BTC. Key molecular markers, such as isocitrate dehydrogenase (IDH) 1 and 2, fibroblast growth factor receptor 2 (FGFR2), BRAF V600E, human epidermal growth factor receptor 2 (HER2), rearranged during transfection (RET), and neurotrophic tyrosine receptor kinase (NTRK), are highlighted for their roles in optimizing treatment regimens. The consensus also explores the significance of emerging biomarkers, such as tumor mutation burden and microsatellite instability, in predicting responses to immune checkpoint inhibitors. The recommendations aim to enhance precision medicine approaches, improve patient outcomes, and foster the integration of molecular diagnostics into routine clinical practice.

Strategies to boost antibody selectivity in oncology

Antibodies in oncology are being equipped with toxic cargoes and effector functions that can kill cells at very low concentrations. A key challenge is that most targets on cancer cells are also present on at least some healthy cells. Shared targets can result in off-tumor binding and compromise the safety and potential of therapeutic candidates. In this review, we survey strategies that can help direct biologics to cancer sites more selectively. These strategies are becoming increasingly feasible thanks to advances in molecular design and engineering. The objective is to create therapeutics that exploit changes in cancer and leverage the human body infrastructure, enabling therapeutics that discriminate not just self from non-self but diseased from healthy tissue.

The emerging HER2 landscape in colorectal cancer: the key to unveil the future treatment algorithm?

Colorectal cancer (CRC) represents a global health threat, standing as the second leading cause of cancer-related death worldwide. Targeted therapies brought new hope for the metastatic stage, which historically bore a very poor prognosis. Human epidermal growth receptor 2 (HER2) overexpression concerns about 5 % of the metastatic CRC (mCRC) patients, including both gene amplifications and point mutations. Albeit its controversial prognostic role, preclinical and clinical data indicate HER2 as a negative predictive biomarker of response to anti-EGFR therapies. Tissue and plasma-based NGS testing, could permit a precise identification of this resistance mechanism both at baseline and during treatment, thus guiding decision-making. Furthermore, promising results come from completed and ongoing randomized trials, testing HER2 as an actionable target. In this review, we discuss the available evidence on HER2 targeting in advanced CRC, analyzing its possible future role in the treatment algorithm.

[Molecular profiling in biliary tract cancers: A national practice survey of French platforms]

INTRODUCTION

Molecular profiling has become essential in the management of patients with biliary tract cancer (BTC). The aim of this study was to evaluate the practices of French genetics platforms in the management of BTCs.

METHODS

A survey was developed by a multidisciplinary group and distributed to each of the 28 French genetics platforms over a one-month period.

RESULTS

Twenty-one platforms answered the survey (75%). A majority (62%) had performed more than 50 analyses for BTCs over the last two years, with an average turnaround time for results evaluated between 11 and 15 days for 62% of them. Three quarters (76%) of the platforms performed both DNA and RNA analysis, while a quarter (24%) performed RNA analysis only. A commercial panel was used by 50% of platforms for DNA analysis, and 80% for RNA. Panels included between 10 and 50 genes for 76% of platforms. All responding platforms systematically tested for IDH1 mutations, FGFR2 fusions and BRAF mutations. A majority systematically tested for HER2 amplification, MSI status and TP53 mutation (88%, 81% and 69% respectively).

DISCUSSION

This national survey of French genetics platforms shows good performance and compliance with recommendations for molecular analysis. However, many medical, financial and organizational obstacles remain upstream of these platforms.

Targeting HER2 in solid tumors: Unveiling the structure and novel epitopes

Human epidermal growth factor receptor-2 (HER2) is overexpressed in various solid tumor types, acting as an established therapeutic target. Over the last three decades, the fast-paced development of diverse HER2-targeted agents, notably marked by the introduction of the antibody-drug conjugate (ADC), yielding substantial improvements in survival rates. However, resistance to anti-HER2 treatments continues to pose formidable challenges. The complex structure and dynamic dimerization properties of HER2 create significant hurdles in the development of novel targeted therapeutics. In this review, we synthesize the latest insights into the structural intricacies of HER2 and present an unprecedented overview of the epitope characteristics of HER2-targeted antibodies and their derivatives. Furthermore, we delve into the correlation between anti-HER2 antibody binding epitopes and their respective functions, with a particular focus on their efficacy against resistant tumors. In addition, we highlight the potential of emerging anti-HER2 agents that target specific sites or non-overlapping epitopes, poised to transform the therapeutic landscape for HER2-positive tumors in the foreseeable future.

Clinical Progresses and Challenges of Bispecific Antibodies for the Treatment of Solid Tumors

In recent years, bispecific antibodies (BsAbs) have emerged as a promising therapeutic strategy against tumors. BsAbs can recruit and activate immune cells, block multiple signaling pathways, and deliver therapeutic payloads directly to tumor sites. This review provides a comprehensive overview of the recent advances in the development and clinical application of BsAbs for the treatment of solid tumors. We discuss the different formats, the unique mechanisms of action, and the clinical outcomes of the most advanced BsAbs in solid tumor therapy. Several studies have also analyzed the clinical progress of bispecific antibodies. However, this review distinguishes itself by exploring the challenges associated with bispecific antibodies and proposing potential solutions. As the field progresses, BsAbs hold promise to redefine cancer treatment paradigms and offer new hope to patients with solid tumors.