Histological predictors of aggressive recurrence of hepatocellular carcinoma after liver resection.

BACKGROUND AND AIMS: Assessment of recurrence risk after liver resection (LR) is critical in hepatocellular carcinoma (HCC), particularly with the advent of effective adjuvant therapy. The aim of the study was to analyze the clinical and pathological factors associated with recurrence, aggressive recurrence, and survival after LR. METHOD: Retrospective study in which all single HCC (BCLC-0/A) patients treated with LR between February 2000 and November 2020 were included. The main clinical variables were recorded. Histological features were blindly evaluated by two independent pathologists. Aggressive recurrence was defined as those that exceeded the Milan criteria at 1st recurrence. RESULTS: A total of 218 patients were included (30% BCLC 0 and 70% BCLC A), median (IQR) tumor size of 28 (19-42mm). The prevalence of microvascular invasion and/or satellitosis (mVI/S) was 39%, with a kappa-index between both pathologists of 0.8. After a median follow-up of 49 (23-85) months, 61/218 (28%) patients died, 32/218 (15%) underwent LT, 127 (58%) developed HCC recurrence. The prevalence of aggressive recurrence was 35% (44/127 Milan-out, with 20 cases at advanced stage), and the 5-year survival was 81%. The presence of mVI/S was the only independent predictor of recurrence [HR:1.83 (1.28-2.61), p<0.001], aggressive recurrence [HR:3.31(1.74-6.29), p<0.001] and mortality [HR:2.23(1.27- 3.91), p:0.005]. The presence of MTM was significantly associated with a higher prevalence of mVI/S, Edmonson Steiner grade III-IV, AFP values and vessels that encapsulate tumor clusters, but MTM was not significantly associated with recurrence, aggressive recurrence, or OS. CONCLUSION: The presence of mVI/S was the only independent risk factor for aggressive recurrence and mortality. This has important implications for early-stage patient management, especially in the setting of adjuvant immunotherapy or ab initio LT.

Incidence of Liver and Non-liver Cancers After Hepatitis C Virus Eradication: A Population-Based Cohort Study.

BACKGROUND AND OBJECTIVES: Direct-acting antivirals (DAAs) offer a high rate of hepatitis C virus (HCV) eradication. However, concerns on the risk of cancer after HCV eradication remain. Our study aimed at quantifying the incidence of cancer in patients treated with anti-HCV therapies in Catalonia (Spain) and their matched controls. METHODS: This was a population-based study using real-world data from the public healthcare system of Catalonia between 2012 and 2016. Propensity score matching was performed in patients with HCV infection treated with interferon-based therapy (IFN), sequential IFN and DAA (IFN+DAA), and DAA only (DAA) with concurrent controls. We estimated the annual incidence of overall cancer, hepatocellular carcinoma, and non-liver cancer of HCV-treated patients and their corresponding rate ratios. RESULTS: The study included 11,656 HCV-treated patients and 49,545 controls. We found statistically significant increases in the rate of overall cancer for IFN+DAA-treated (rate ratio [RR] 1.77, 95% confidence interval [CI] 1.27-2.46) and DAA-treated patients (RR 1.90, 95% CI 1.66-2.19) and in the rate of HCC for IFN-treated (RR 1.50, 95% CI 1.02-2.22), IFN+DAA-treated (RR 3.89, 95% CI 2.26-6.69), and DAA-treated patients (RR 6.45, 95% CI 4.90-8.49) compared with their corresponding controls. Moreover, DAA-treated patients with cirrhosis showed an increased rate of overall cancer versus those without cirrhosis (RR 1.92, 95% CI 1.51-2.44). CONCLUSIONS: Results showed that overall cancer and hepatocellular carcinoma incidence in Catalonia was significantly higher among HCV-treated patients compared with matched non-HCV-infected controls, and risks were higher in patients with cirrhosis. An increased awareness of the potential occurrence of uncommon malignant events and monitoring after HCV eradication therapy may benefit patients.

Direct-acting antivirals (DAAs) are effective drugs for eradicating hepatitis C virus (HCV). However, concerns about the risk of cancer after HCV eradication remain. Therefore, this study aimed to compare the incidence of cancer between patients treated with anti-HCV therapies in Catalonia (Spain) and properly matched, non-HCV-infected individuals (controls).This study was based on real-world data from the public healthcare system of Catalonia, specifically from patients with HCV infection treated with interferon-based therapy (IFN), sequential IFN and DAA (IFN+DAA), or DAA only (DAA). We calculated the incidence and rate ratios of overall cancer and hepatocellular carcinoma of HCV-treated patients.We observed that the rate of overall cancer increased in patients receiving DAA or IFN+DAA, whereas the rate of hepatocellular carcinoma increased in all groups of HCV-treated patients. Of note, DAA-treated patients with cirrhosis showed an increased rate of overall cancer versus those without cirrhosis. Thus, a close monitoring for detection of cancer in patients after HCV eradication seems reasonable, especially in those with cirrhosis.

MRI Using Gadoxetic Acid in the Work-Up of Liver Nodules Not Conclusively Benign in Budd-Chiari Syndrome: A Prospective Long-Term Follow-Up.

Introduction: The incidence of hepatocellular carcinoma (HCC) in Budd-Chiari syndrome (BCS) is unknown and there is no validated diagnostic work-up to define the liver nodules with arterial phase hyperenhancement (APHE), suggesting malignancy. This prospective study evaluates HCC incidence in a Western cohort of patients with BCS and assesses the performance of MRI with hepatobiliary contrast (HB-MRI) for nodule characterization. Methods: Patients with BCS followed in our hospital were prospectively evaluated by MRI with extracellular contrast (EC-MRI). Nodules with APHE categorized as non-conclusively benign by 2 radiologists were studied by HB-MRI and reviewed by 2 radiologists blinded to the EC-MRI results. A new EC-MRI 1 year later and clinical, analytical, and sonographic follow-up every 6 months for a median of 10 years was performed. Results: A total of 55 non-conclusively benign nodules with APHE were detected at EC-MRI in 41 patients. While 32 of them were suggestive of HCC by EC-MRI, all the 55 nodules showed increased uptake of hepatobiliary contrast. An unequivocal central scar was seen in 12/55 nodules at HB-MRI regardless of it was not detected on the EC-MRI. None of the nodules was hypointense in the hepatobiliary phase (HBP). HCC was not detected during a median of 10 years of follow-up. Conclusions: Detection of nodules with APHE is frequent in patients with BCS, but HCC is rare in Western patients with BCS. While EC-MRI may detect nodules suggesting malignancy, the identification of contrast uptake in the HBP at HB-MRI may help categorize them as benign.

Metallothionein-3 is a multifunctional driver that modulates the development of sorafenib-resistant phenotype in hepatocellular carcinoma cells.

BACKGROUND & AIMS: Metallothionein-3 (hMT3) is a structurally unique member of the metallothioneins family of low-mass cysteine-rich proteins. hMT3 has poorly characterized functions, and its importance for hepatocellular carcinoma (HCC) cells has not yet been elucidated. Therefore, we investigated the molecular mechanisms driven by hMT3 with a special emphasis on susceptibility to sorafenib. METHODS: Intrinsically sorafenib-resistant (BCLC-3) and sensitive (Huh7) cells with or without up-regulated hMT3 were examined using cDNA microarray and methods aimed at mitochondrial flux, oxidative status, cell death, and cell cycle. In addition, in ovo/ex ovo chick chorioallantoic membrane (CAM) assays were conducted to determine a role of hMT3 in resistance to sorafenib and associated cancer hallmarks, such as angiogenesis and metastastic spread. Molecular aspects of hMT3-mediated induction of sorafenib-resistant phenotype were delineated using mass-spectrometry-based proteomics. RESULTS: The phenotype of sensitive HCC cells can be remodeled into sorafenib-resistant one via up-regulation of hMT3. hMT3 has a profound effect on mitochondrial respiration, glycolysis, and redox homeostasis. Proteomic analyses revealed a number of hMT3-affected biological pathways, including exocytosis, glycolysis, apoptosis, angiogenesis, and cellular stress, which drive resistance to sorafenib. CONCLUSIONS: hMT3 acts as a multifunctional driver capable of inducing sorafenib-resistant phenotype of HCC cells. Our data suggest that hMT3 and related pathways could serve as possible druggable targets to improve therapeutic outcomes in patients with sorafenib-resistant HCC.

Navigating the landscape of liver cancer management: Study designs in clinical trials and clinical practice.

Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer death worldwide and its prognosis is highly heterogeneous, being related not only to tumour burden but also to the severity of underlying chronic liver disease. Moreover, advances in systemic therapies for HCC have increased the complexity of patient management. Randomised-controlled trials represent the gold standard for evidence generation across all areas of medicine and especially in the oncology field, as they allow for unbiased estimates of treatment effect without confounders. Observational studies have many problems that could reduce their internal and external validity. However, large prospective (well-conducted) observational real-world studies can detect rare adverse events or monitor the occurrence of long-term adverse events. How best to harness real world data, which refers to data generated from the routine care of patients, and real-world 'evidence', which is the evidence generated from real-world data, represents an open challenge. In this review article, we aim to provide an overview of the benefits and limitations of different study designs, particularly focusing on randomised-controlled trials and observational studies, to address important and not fully resolved questions in HCC research.

Risk of Treatment Failure and Death after Ablation in Hepatocellular Carcinoma Patients-A Multiparametric Prediction.

BACKGROUND: Ablation is a first-line treatment for Barcelona Clinic Liver Cancer (BCLC)-0/A hepatocellular carcinoma (HCC). However, there are scarce data about patients' outcomes after recurrence. The present study evaluates the impact of patient and tumor characteristics at baseline and at recurrence on the Clinical Decision-Making process. METHODS: We evaluated BCLC-0/A patients treated with percutaneous ablation from January 2010 to November 2018. Clinical and radiological data such as age, tumor location at ablation, pattern of recurrence/progression, and comorbidities during follow-up were registered. Tumor location was divided into 'suboptimal' vs. 'optimal' locations for ablation. The Clinical Decision-Making was based on tumor burden, liver dysfunction, or comorbidities. The statistical analysis included the time-to-recurrence/progression, censoring at time of death, date of last follow-up or liver transplantation, and time-to-event was estimated by the Kaplan-Meier method and Cox regression models to evaluate the risk of an event of death and change of treatment strategy. RESULTS: A total of 225 patients [39.1% BCLC-0 and 60.9% BCLC-A] were included, 190 had unifocal HCC and 82.6% were ≤3 cm. The complete response rate and median overall survival were 96% and 60.7 months. The HCC nodules number (Hazard Ratio-HR 3.1), Child-Pugh (HR 2.4), and Albumin-Bilirubin score (HR 3.2) were associated with increased risk of death during follow-up. HCC in 'suboptimal location' presented a shorter time to recurrence. When comorbidities prevented further loco-regional or systemic treatment, the risk of death was significantly increased (HR 2.0, p = 0.0369) in comparison to those who received treatment. CONCLUSIONS: These results expose the impact of non-liver comorbidities when considering treatment for recurrence after ablation in the real-world setting and in research trials. Ultimately, we identified an orphan population for which effective interventions are needed.

Breakthroughs in Hepatocellular Carcinoma Therapies.

Several breakthroughs in hepatocellular carcinoma (HCC) therapy across tumor stages provide hope to improve its dismal prognosis. Although surgical and local ablative therapies have few significant changes in technique, an improved understanding of tumor biology has facilitated increase numbers of patients who are now eligible to undergo curative-intent procedures. Most notably, acceptable post-transplant outcomes can be achieved in well selected patients whose tumors are downstaged into Milan Criteria. Adjuvant therapy in patients at high risk of recurrence also significantly improves recurrence-free survival after resection or ablation. For patients with liver-localized disease who are not eligible for curative-intent procedures, transarterial chemoembolization (TACE) was historically the treatment modality of choice, regardless of tumor burden; however, there is now increased recognition of patients who are "TACE unsuitable" and may be better treated with systemic therapy. The greatest evolution in HCC treatment options has occurred with systemic therapy, where several new agents are now available in the first- and second-line setting, including immune checkpoint inhibitor combinations. Objective responses are observed in approximately 30% of patients and median survival is approaching 2 years. The availability of immune checkpoint inhibitors has renewed interest in combination therapies for earlier tumor stages, with several phase III trials ongoing. Considering increasing complexities of HCC care, requiring decisions between therapies delivered by different providers, multidisciplinary care is critical and is associated with improved clinical outcomes. In this review, we detail major breakthroughs in HCC therapy, how these breakthroughs can be applied in clinical practice, and remaining areas in need of further research.

Transarterial Chemoembolization with Anthracyclines-Loaded Polyethylene Glycol Drug Eluting Microspheres for the Treatment of Hepatocellular Carcinoma: A Pooled Multicentric Analysis of Survival in 580 Patients.

PURPOSE: To evaluate survival, efficacy and safety of transarterial chemoembolization (TACE) in the treatment of patients with hepatocellular carcinoma (HCC), through a pooled analysis of patients with BCLC 0, A and B HCC stages, treated with polyethylene glycol drug eluting microspheres (PEG-DEM) TACE. MATERIALS AND METHODS: Patients from 3 retrospective and 2 prospective registries were included. Overall survival (OS), progression-free survival (PFS), tumour response and safety were evaluated. Multivariate Cox regression analysis was performed to evaluate predictors of OS. RESULTS: A total of 580 patients (72.1% males, mean age 66.9 ± 10.3 years) were included. 43.5% had BCLC A, and 41.0% BCLC B disease stage, and 85.8% were Child-Pugh class A. Complete and partial response (mRECIST or RECIST1.1) were achieved in 60.14% and 27.11% of patients, with overall response and disease control rates of 87.30% and 94.60%, respectively. Median OS was 50.8 months for the total population, and 61.2 and 38.1 months for BCLC 0 + A and BCLC B patients, respectively. Median PFS for the total population, BCLC 0 + A and BCLC B groups was 15.6, 21.6 and 12.7 months, respectively. CONCLUSIONS: This multicentric pooled analysis confirmed efficacy and safety of PEG-DEM TACE, with a median OS of 50.8 months.

Outcome of patients with HCC and liver dysfunction under immunotherapy: a systematic review and meta-analysis.

BACKGROUND AND AIMS: Immunotherapy-based regimes have changed the management of HCC. However, evidence of efficacy in patients with impaired liver function is unknown. This systematic review and meta-analysis assesses survival of HCC patients and liver dysfunction treated with immunotherapy-based regimens. METHODS: Systematic review and meta-analysis of original articles or abstracts reporting survival of HCC patients treated with immunotherapy according to liver function between 2017 and 2022. Overal survival (OS) according to restricted mean survival time (RMST) and median OS, and hazard ratio (HR) of Child-Pugh B or B/C versus Child-Pugh A were assessed while considering the line of treatment. RESULTS: Of the 2218 articles considered, 15 articles recruiting 2311 patients were included. Of these, 639 (27.7%) were Child-Pugh B and 34 (1.5%) C. RMST was 8.36 (95% CI, 6.15-10.57; I2 =93%) months, estimated from 8 studies. The HR was reported in 8 studies for survival between Child-Pugh B versus Child-Pugh A and metanalysis disclosed a 1.65 HR (95% CI,1.45-1.84; I2 =0% heterogeneity; p = 0.45). Treatment line data were available for 47% of the patients and 3 studies included patients treated with atezolizumab-bevacizumab in the first line. CONCLUSIONS: The high heterogeneity across studies reflects the incapacity of the current evidence to support the indication of immunotherapy in HCC patients with relevant liver dysfunction. It is mandatory to report complementary information to Child-Pugh classification such as prior liver decompensation, use of concomitant medication to control ascites, or signs of clinically significant portal hypertension to allow better patient stratification in future studies.

Nivolumab Plus Cabozantinib With or Without Ipilimumab for Advanced Hepatocellular Carcinoma: Results From Cohort 6 of the CheckMate 040 Trial.

PURPOSE: To investigate the safety and efficacy of nivolumab plus cabozantinib with or without ipilimumab in patients with advanced hepatocellular carcinoma. METHODS: In cohort 6 of the multicohort, open-label, phase I/II CheckMate 040 study, patients who were treatment-naive, sorafenib-intolerant, or had progressed on sorafenib were randomly assigned 1:1 to nivolumab 240 mg once every 2 weeks plus cabozantinib 40 mg once daily (doublet arm); or nivolumab 3 mg/kg every 2 weeks plus cabozantinib 40 mg once daily with ipilimumab 1 mg/kg once every 6 weeks (triplet arm). Primary objectives were safety and tolerability, objective response rate, and duration of response by investigator assessment per RECIST v1.1. Secondary objectives included progression-free survival (by blinded independent central review) and overall survival. RESULTS: Seventy-one patients were randomly assigned: 36 to the doublet arm and 35 to the triplet arm. After 32.0-month median follow-up, objective response rate (95% CI) was 17% (6 to 33) and 29% (15 to 46) in the doublet and triplet arms, respectively. Median (95% CI) duration of response was 8.3 (6.9 to not estimable) months in the doublet arm and not reached (0.0 to not estimable) in the triplet arm. Median progression-free survival was 5.1 and 4.3 months, and median overall survival was 20.2 and 22.1 months for the doublet and triplet arms, respectively. Grade 3-4 treatment-related adverse events occurred in 50% and 74% of patients and treatment-related adverse events leading to discontinuation were reported for 11% and 23% in the doublet and triplet arms, respectively. There were no treatment-related deaths in either arm. CONCLUSION: Nivolumab plus cabozantinib with or without ipilimumab showed encouraging preliminary antitumor activity and had consistent safety profiles with those established for the individual drugs in patients with advanced hepatocellular carcinoma.

What to do about hepatocellular carcinoma: Recommendations for health authorities from the International Liver Cancer Association.

Hepatocellular carcinoma (HCC) is a major public health problem worldwide for which the incidence and mortality are similar, pointing to the lack of effective treatment options. Knowing the different issues involved in the management of HCC, from risk factors to screening and management, is essential to improve the prognosis and quality of life of affected individuals. This document summarises the current state of knowledge and the unmet needs for all the different stakeholders in the care of liver cancer, meaning patients, relatives, physicians, regulatory agencies and health authorities so that optimal care can be delivered to patients. The document was commissioned by the International Liver Cancer Association and was reviewed by senior members, including two ex-presidents of the Association. This document lays out the recommended approaches to the societal management of HCC based on the economic status of a given region.

Polymorphism AGT2 (rs4762) is involved in the development of dermatologic events: Proof-of-concept in hepatocellular carcinoma patients treated with sorafenib.

BACKGROUND: Dermatologic adverse events (DAEs) are associated with a better outcome in patients with hepatocellular carcinoma (HCC) irrespective of the therapeutic agent received. The exact mechanisms associated with the development of DAEs are unknown although several studies point to direct toxicity of tyrosine kinase inhibitors (TKIs) to the skin or an immune-mediated reaction triggered by the oncologic treatment. As is the case in other conditions, individual genetic variants may partially explain a higher risk of DAEs. AIM: To evaluate the contribution of several gene variants to the risk of developing DAEs in HCC patients treated with TKIs. METHODS: We first analyzed 27 single-nucleotide polymorphisms (SNPs) from 12 genes selected as potential predictors of adverse event (AE) development in HCC patients treated with sorafenib [Barcelona Clinic Liver Cancer 1 (BCLC1) cohort]. Three additional cohorts were analyzed for AGT1 (rs699) and AGT2 (rs4762) polymorphisms-initially identified as predictors of DAEs: BCLC2 (n = 79), Northern Italy (n = 221) and Naples (n = 69) cohorts, respectively. The relation between SNPs and DAEs and death were assessed by univariate and multivariate Cox regression models, and presented with hazard ratios and their 95% confidence intervals (95%CI). RESULTS: The BCLC1 cohort showed that patients with arterial hypertension (AHT) (HR = 1.61; P value = 0.007) and/or AGT SNPs had an increased risk of DAEs. Thereafter, AGT2 (rs4762) AA genotype was found to be linked to a statistically significant increased probability of DAEs (HR = 5.97; P value = 0.0201, AA vs GG) in the Northern Italy cohort by multivariate analysis adjusted for BCLC stage, ECOG-PS, diabetes and AHT. The value of this genetic marker was externally validated in the cohort combining the BCLC1, BCLC2 and Naples cohorts [HR = 3.12 (95%CI: 1.2-8.14), P value = 0.0199, AGT2 (rs4762) AA vs AG genotype and HR = 2.73 (95%CI: 1.18-6.32) P value = 0.0188, AGT2 (rs4762) AA vs GG genotype]. None of the other gene variants tested were found to be associated with the risk of DAE development. CONCLUSION: DAE development in HCC patients receiving TKIs could be explained by the AGT2 (rs4762) gene variant. If validated in other anti-oncogenic treatments, it might be considered a good prognosis marker.

miR-200c-3p, miR-222-5p, and miR-512-3p Constitute a Biomarker Signature of Sorafenib Effectiveness in Advanced Hepatocellular Carcinoma.

BACKGROUND: Sorafenib constitutes a suitable treatment alternative for patients with advanced hepatocellular carcinoma (HCC) in whom atezolizumab + bevacizumab therapy is contraindicated. The aim of the study was the identification of a miRNA signature in liquid biopsy related to sorafenib response. METHODS: miRNAs were profiled in hepatoblastoma HepG2 cells and tested in animal models, extracellular vesicles (EVs), and plasma from HCC patients. RESULTS: Sorafenib altered the expression of 11 miRNAs in HepG2 cells. miR-200c-3p and miR-27a-3p exerted an anti-tumoral activity by decreasing cell migration and invasion, whereas miR-122-5p, miR-148b-3p, miR-194-5p, miR-222-5p, and miR-512-3p exerted pro-tumoral properties by increasing cell proliferation, migration, or invasion, or decreasing apoptosis. Sorafenib induced a change in EVs population with an increased number of larger EVs, and promoted an accumulation of miR-27a-3p, miR-122-5p, miR-148b-3p, miR-193b-3p, miR-194-5p, miR-200c-3p, and miR-375 into exosomes. In HCC patients, circulating miR-200c-3p baseline levels were associated with increased survival, whereas high levels of miR-222-5p and miR-512-3p after 1 month of sorafenib treatment were related to poor prognosis. The RNA sequencing revealed that miR-200c-3p was related to the regulation of cell growth and death, whereas miR-222-5p and miR-512-3p were related to metabolic control. CONCLUSIONS: The study showed that Sorafenib regulates a specific miRNA signature in which miR-200c-3p, miR-222-5p, and miR-512-3p bear prognostic value and contribute to treatment response.

Portal hypertension may influence the registration of hypointensity of small hepatocellular carcinoma in the hepatobiliary phase in gadoxetic acid MR.

BACKGROUND: The aim of the study was to analyze the association between the liver uptake of Gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid (Gd-EOB-DTPA) in the hepatobiliary phase (HBP) in cirrhotic patients and the presence of clinically significant portal hypertension (CSPH), and how these features impact on hepatocellular carcinoma (HCC) detection in the HBP. PATIENTS AND METHODS: Post-hoc analysis of a prospective cohort of 62 cirrhotic patients with newly US-detected nodule between 1-2 cm (study group). Twenty healthy subjects were used as control group. Qualitative and quantitative analysis of the liver contrast uptake in the HBP assessed by Relative Liver-Enhancement (RLE), Liver-Spleen (LSCR), Liver-Muscle (LMCR), and Liver-Kidney Contrast-Ratio (LKCR), Contrast Enhancement Index (CEI), and Hepatic Uptake (HUI), and biliary excretion, were registered. CSPH was confirmed invasively (HVPG > 10 mmHg) or by indirect parameters. The appearance of HCC at the HBP was analyzed. RESULTS: Nineteen patients (30.6%) did not have CSPH. In 41 patients (66.1%) the final diagnosis was HCC. All indices were significantly higher in the control group, indicating a more intense HBP liver signal intensity compared to patients with cirrhosis, even if the comparison was restricted to patients with no CSPH. CSPH was associated to a lower rate of HCC hypointensity in the HBP (51.9% vs. 85.7% without CSPH, p = 0.004). CONCLUSIONS: Liver uptake of Gd-EOB-DTPA at the HBP is decreased in cirrhosis even if the liver function is minimally impaired and it falls down significantly in patients with CSPH compromising the recognition of hypointense lesions. This fact may represent a limitation for the detection of small HCC in patients with cirrhosis and CSPH.

A first-in-human phase 1/2 study of FGF401 and combination of FGF401 with spartalizumab in patients with hepatocellular carcinoma or biomarker-selected solid tumors.

BACKGROUND: Deregulation of FGF19-FGFR4 signaling is found in several cancers, including hepatocellular carcinoma (HCC), nominating it for therapeutic targeting. FGF401 is a potent, selective FGFR4 inhibitor with antitumor activity in preclinical models. This study was designed to determine the recommended phase 2 dose (RP2D), characterize PK/PD, and evaluate the safety and efficacy of FGF401 alone and combined with the anti-PD-1 antibody, spartalizumab. METHODS: Patients with HCC or other FGFR4/KLB expressing tumors were enrolled. Dose-escalation was guided by a Bayesian model. Phase 2 dose-expansion enrolled patients with HCC from Asian countries (group1), non-Asian countries (group2), and patients with other solid tumors expressing FGFR4 and KLB (group3). FGF401 and spartalizumab combination was evaluated in patients with HCC. RESULTS: Seventy-four patients were treated in the phase I with single-agent FGF401 at 50 to 150 mg. FGF401 displayed favorable PK characteristics and no food effect when dosed with low-fat meals. The RP2D was established as 120 mg qd. Six of 70 patients experienced grade 3 dose-limiting toxicities: increase in transaminases (n = 4) or blood bilirubin (n = 2). In phase 2, 30 patients in group 1, 36 in group 2, and 20 in group 3 received FGF401. In total, 8 patients experienced objective responses (1 CR, 7 PR; 4 each in phase I and phase II, respectively). Frequent adverse events (AEs) were diarrhea (73.8%), increased AST (47.5%), and ALT (43.8%). Increase in levels of C4, total bile acid, and circulating FGF19, confirmed effective FGFR4 inhibition. Twelve patients received FGF401 plus spartalizumab. RP2D was established as FGF401 120 mg qd and spartalizumab 300 mg Q3W; 2 patients reported PR. CONCLUSIONS: At biologically active doses, FGF401 alone or combined with spartalizumab was safe in patients with FGFR4/KLB-positive tumors including HCC. Preliminary clinical efficacy was observed. Further clinical evaluation of FGF401 using a refined biomarker strategy is warranted. TRIAL REGISTRATION: NCT02325739 .