Purpose: Modified gemcitabine and S-1 (GS) is an active regimen for patients with advanced biliary tract cancer (ABTC) in our previous study. Herein, we report the results of a single-arm phase II of nivolumab plus modified GS (NGS) as first-line treatment in ABTC. Patients and Methods: Patients received nivolumab 240 mg and 800 mg/m2 gemcitabine on day 1 plus daily 80/100/120 mg of S-1 (based on body surface area) on days 1 to 10, in a 2-week cycle. The primary endpoint was the objective response rate (ORR). The correlation between therapeutic efficacy and genetic alterations with signatures identified by targeted next-generation sequencing panels was explored. Results: Between December 2019 and December 2020, 48 eligible patients were enrolled. After a median of 17.6 months of follow-up, the ORR was 45.9% [95% confidence interval (CI), 31.4%–60.8%]. The median progression-free survival (PFS) and overall survival (OS) was 9.1 (95% CI, 5.8–9.6) and 19.2 (95% CI, 11.6–not reached) months, respectively. All grade 3/4 treatment-related adverse events (AE) were less than 10%, except fatigue (14.6%) and skin rash (10.4%). Eighteen patients (35.4%) experienced immune-related AEs without treatment-related death. High tumor mutational burden (TMB-H; top 20%; ≥7.1 mut/Mb) only predicted prolonged median PFS but not OS. Up to 28.9% of patients who harbored loss-of-function mutations in chromatin remodeling genes demonstrated significantly longer median PFS and OS than those without alterations. Conclusions: NGS is a safe and promising regimen in ABTC. Impaired functions of chromatin remodeling genes may be a potential surrogate biomarker with predictive value in this study.

Oxaliplatin is effective against colorectal cancer (CRC), but resistance hampers treatment. We found upregulated Dickkopf-1 (DKK1, a secreted protein) in oxaliplatin-resistant (OR) CRC cell lines and DKK1 levels increased by more than 2-fold in approximately 50% of oxaliplatin-resistant CRC tumors. DKK1 activates AKT via cytoskeleton-associated protein 4 (CKAP4, a DKK1 receptor), modulating oxaliplatin responses in vitro and in vivo. The leucine zipper (LZ) domain of CKAP4 and cysteine-rich domain 1 (CRD1) of secreted DKK1 are crucial for their interaction and AKT signaling. By utilizing the LZ protein, we disrupted DKK1 signaling, enhancing oxaliplatin sensitivity in OR CRC cells and xenograft tumors. This suggests that DKK1 as a chemoresistant factor in CRC via AKT activation. Targeting DKK1 with the LZ protein offers a promising therapeutic strategy for oxaliplatin-resistant CRC with high DKK1 levels. This study sheds light on oxaliplatin resistance mechanisms and proposes an innovative intervention for managing this challenge.

International guidelines recommend ivosidenib followed by modified FOLFOX (mFOLFOX) for advanced intrahepatic cholangiocarcinoma (ICC) with isocitrate dehydrogenase 1 (IDH1) mutations. Taiwan National Health Insurance covers only fluorouracil/leucovorin (5-FU/LV) chemotherapy for this ICC group, and there has been no prior economic evaluation of ivosidenib. Therefore, we aimed to assess ivosidenib’s cost-effectiveness in previously treated, advanced ICC-presenting IDH1 mutations compared with mFOLFOX or 5-FU/LV. A 3-state partitioned survival model was employed to assess ivosidenib’s cost-effectiveness over a 10-year horizon with a 3% discount rate, setting the willingness-to-pay threshold at 3 times the 2022 GDP per capita. Efficacy data for Ivosidenib, mFOLFOX, and 5-FU/LV were sourced from the ClarIDHy, ABC06, and NIFTY trials, respectively. Ivosidenib’s cost was assumed to be NT$10,402/500 mg. Primary outcomes included incremental cost-effectiveness ratios (ICERs) and net monetary benefit. Deterministic sensitivity analyses (DSA) and probabilistic sensitivity analyses (PSA) were employed to evaluate uncertainty and explore price reduction scenarios. Ivosidenib exhibited ICERs of NT$6,268,528 and NT$5,670,555 compared with mFOLFOX and 5-FU/LV, respectively, both exceeding the established threshold. PSA revealed that ivosidenib was unlikely to be cost-effective, except when it was reduced to NT$4,161 and NT$5,201/500 mg when compared with mFOLFOX and 5-FU/LV, respectively. DSA underscored the significant influence of ivosidenib’s cost and utility values on estimate uncertainty. At NT$10,402/500 mg, ivosidenib was not cost-effective for IDH1-mutant ICC patients compared with mFOLFOX or 5-FU/LV, indicating that a 50–60% price reduction is necessary for ivosidenib to be cost-effective in this patient group.

Background: In December 2022, the Taiwan National Health Insurance Administration (NHIA) announced the reimbursement of three dosages of pemigatinib 4.5 mg, 9 mg, and 13.5 mg for treating advanced intrahepatic cholangiocarcinoma (ICC) with fibroblast growth factor receptor 2 (FGFR2) fusions/rearrangements and set the reimbursement price for pemigatinib 4.5 mg at NT$6600. This study aims to analyze the cost-effectiveness of pemigatinib 13.5 mg as a second-line treatment compared to mFOLFOX and 5-FU chemotherapy for advanced ICC patients with FGFR2 fusions/rearrangements from the perspective of Taiwan’s NHIA. Methods: This study used a 3-state partitioned survival model to analyze the 5 year cost-effectiveness of pemigatinib as a second-line treatment for advanced ICC patients in whom first-line gemcitabine-based chemotherapy failed and to compare the results with those for the mFOLFOX and 5-FU chemotherapy regimens. Overall survival and progression-free survival were estimated from the FIGHT-202 trial (pemigatinib), ABC-06 trial (mFOLFOX), and NIFTY trial (5-FU). The price of pemigatinib 13.5 mg was set at the potentially highest listing price (NT$17,820). Other parameters of utility, disutility, and costs related to advanced ICC were obtained from the published literature. The willingness-to-pay threshold was three times the forecasted gross domestic product per capita in 2022 (NT$2,928,570). A 3% discount rate was applied to quality-adjusted life-years (QALYs) and costs. Several scenario analyses were performed, including a gradual price reduction for pemigatinib. Deterministic sensitivity analysis, probabilistic sensitivity analysis (PSA), and value of information were performed to assess uncertainty. Results: Pemigatinib was not cost-effective compared to mFOLFOX or 5-FU in the base-case analysis. When the price of pemigatinib was reduced by 50% or more, pemigatinib gained a positive net monetary benefit (mFOLFOX: NT$55,374; 5-FU: NT$92,437) and a 72% (mFOLFOX) and 77.1% (5-FU) probability of being cost-effective. Most of the uncertainty came from the medication cost of pemigatinib, health state utility, and the overall survival associated with pemigatinib. Conclusions: According to the NCCN guidelines, the daily use of pemigatinib 13.5 mg at the hypothesized NHIA price of NT$17,820/13.5 mg was not cost-effective compared to mFOLFOX or 5-FU. The price reduction scenario suggested a 50% price reduction, NT$8910 per 13.5 mg, for advanced ICC patients with FGFR2 fusions/rearrangements.

Background & Aims: Gemcitabine plus cisplatin (GC) remains the standard, frontline therapy for advanced biliary tract cancer (ABTC). The JCOG1113 study suggested that gemcitabine plus S‐1 (GS) had noninferior median overall survival and comparable incidence of significant neutropenia as compared to GC treatments. This study evaluates the efficacy and safety of a modified GS regimen.Methods: The eligible patients with chemonaive, measurable ABTC received 800 mg/m² of gemcitabine on day 1 and 80 mg/m²/day of S‐1 (80/100/120 mg for patients with body surface <1.25/ ≥1.25 and <1.5/ ≥1.5 m² respectively). The primary endpoint was the 12‐week disease control rate (12‐week DCR: objective response and stable disease ≥ 12 weeks). Per the p0 = 40% and p1 = 60% (α/β = 0.05/0.2) assumption, Simon's optimal two‐stage design indicated 12‐week DCR in ≥ 24 of 46 evaluable patients for significant activity. Tumour responses were assessed every 6 weeks.Results: Fifty‐one patients were enrolled and most of them had intrahepatic cholangiocarcinoma (64.7%), metastatic disease (84.3%) and disease‐related symptoms (82.4%). On intention‐to‐treat analysis, 11 (21.6%) patients showed partial response, whereas 21 (41.2%) showed stable disease ≥ 12 weeks. The progression‐free and overall survival were 5.4 months (95% confidence interval [CI]: 3.5‐7.0), and 12.7 months (95% CI: 6.1‐15.6) respectively. The study met its primary endpoint with a 12‐week DCR of 69.6% in 46 evaluable patients. Grade 3/4 treatment‐related adverse eventsoccurred in < 6% of patients of all individual items. The mean dose intensities of S‐1 and gemcitabine were 87.1% and 92.5% respectively.Conclusions: Modified GS showed moderate efficacy with a favourable safety profile in ABTC patients, thus mandating further assessment.ClinicalTrials.gov number: NCT02425137.