Bergamo, Francesca

Abstract Purpose: Microsatellite instability (MSI) is currently the only predictive biomarker of efficacy of immune checkpoint inhibitors (ICI) in metastatic colorectal cancers (mCRC). However, 10% to 40% of patients with MSI mCRC will experience a primary resistance to ICI. Experimental Design: In two cohorts of patients with MSI mCRC treated with ICI (exploratory, N = 103; validation, N = 35), 3′ RNA sequencing was performed from primary tumors. Previously described single-cell transcriptomic signatures of tumor microenvironment (TME) were analyzed. Results: In the exploratory cohort, the unsupervised clustering allowed the identification of three clusters of tumors with distinct transcriptional profiles: cluster A (“stromalHIGH-proliferationLOW”), cluster B (“stromalHIGH-proliferationMED”), and cluster C (“stromalLOW-proliferationHIGH”), with an enrichment of patients progressing at first disease assessment under ICI in cluster A (30% vs. 12% in cluster B and 8.1% in cluster C; P = 0.074). Progression-free survival (PFS) was also significantly shorter in patients belonging to cluster A, compared with clusters B or C (P < 0.001) with 2-year PFS rates of 33.5%, 80.5%, and 78.3%, respectively. In multivariate analysis, PFS was still significantly longer in patients belonging to cluster B [HR, 0.19; 95% confidence interval (CI), 0.08–0.45; P < 0.001] and cluster C (HR, 0.25; 95% CI, 0.10–0.59; P = 0.02), compared with patients belonging to cluster A. The association of this clustering with PFS under ICI was confirmed in the validation cohort. PFS related to non–ICI-based regimens was not significantly different according to cluster. Conclusions: This unsupervised transcriptomic classification identified three groups of MSI mCRCs with different compositions of TME cells and proliferative capacities of TME/tumor cells. The “stromalHIGH-proliferationLOW” cluster is associated with a poorer prognosis with ICI treatment.

427 Background: Derazantinib, a potent anti- FGFR1-3 oral kinase inhibitor, has shown clinically meaningful anti-tumor activity (21%), durable responses (median, 6.4 months), and progression-free survival (median, 8.0 months) in patients (pts) with FGFR2 fusion (FGFR2F)-positive intrahepatic cholangiocarcinoma (iCCA), and with a manageable toxicity profile. Herein, we report an interim analysis of the clinical efficacy data of derazantinib for pts with iCCA harboring FGFR2 mutations or amplifications (FGFR2M/A), a potential therapeutic option currently not addressed by FGFR inhibitors. Methods: Study FIDES-01 enrolls in a dedicated cohort pts with FGFR2M/A+ advanced iCCA who received previous chemotherapy. Pts receive 300 mg derazantinib daily until disease progression, death or intolerance. The primary endpoint is the proportion of pts alive and free of disease progression at 3 months (PFS3; RECIST 1.1, central imaging review) using a Simon’s two-stage sample-size minimizing statistical design. The interim analysis population comprises 23 pts dosed (intention to treat) who had at least one post-baseline tumor assessment (or clinical progression, or died) by June 3, 2021, using investigator assessments based on RECIST 1.1. Results: To date, 28 pts have been enrolled and dosed. FGFR2M/A observed in these pts included missense point mutations (78%), other short variants (11%) and amplifications (11%). Transition from stage 1 to stage 2 of the study was achieved earlier than planned after 8 (67%) of 12 pts were assessed as PFS3 based on central imaging review. In 23 pts included in this interim analysis for efficacy, the best overall response (investigator assessment) was confirmed partial response in two (8.7%) and stable disease in additional 15 pts (65.2%), resulting in a disease control rate of 73.9% (95% CI, 51.6–89.8). Using Kaplan-Meier analyses, the median PFS was 7.3 months (95%CI, 3.5–16.7) and the probability of being progression-free at 3 months and at 6 months were 76.3% (95%CI, 51.9–89.4) and 50.3% (95%CI, 21.7–73.4), respectively. Clinically meaningful anti-tumor efficacy was observed across all types of genetic aberrations. The safety profile of derazantinib in FGFR2M/A+ iCCA pts was consistent with that previously reported for FGFR2F+ iCCA pts. Conclusions: This interim data in study FIDES-01 suggest that derazantinib treatment provides clinical benefit to pts with advanced iCCA harboring FGFR2M/A who progressed after at least one line of standard chemotherapy. To our knowledge, this is the first report of clinically meaningful anti-tumor efficacy in a prospectively planned cohort of iCCA pts harboring FGFR2M/A. The study is ongoing to accrue 43 patients, assessing derazantinib as a therapeutic option for FGFR2M/A+ iCCA pts after disease progression on first-line treatment. Clinical trial information: NCT03230318.

AbstractBackgroundPhysical activity may increase the risk of cardiotoxicity (myocardial ischemia, major arrhythmias) of 5-Fluorouracil, but this risk has never been investigated for its prodrug capecitabine.Patients and MethodsOne hundred and ninety-two consecutive patients undergoing capecitabine chemotherapy from December 1, 2010 through July 31, 2016 were prospectively evaluated. The baseline evaluation included electrocardiography (ECG) and echocardiography (2DE); a follow-up evaluation, including ECG and exercise stress testing (2DE in case of ECG abnormalities), was done after ≥10 days of treatment. Cardiotoxicity was suspected from ischemic ECG changes, new kinetic abnormalities at 2DE, Lown classification ≥2 ventricular arrhythmia, symptomatic arrhythmias, or positive stress test, and confirmed by a negative stress test after capecitabine washout.ResultsCardiotoxicity was diagnosed in 32 patients (16.7%): six at rest and 26 during exercise. All 32 patients had ECG abnormalities: ST-segment changes (24 patients), negative T-waves (2) and/or arrhythmias: ventricular arrhythmias (14 cases), supraventricular tachycardia (2), complete heart block (1). Eight patients had typical symptoms, 6 had atypical symptoms, 1 had syncope, 17 (53%) were asymptomatic. Cardiotoxicity was more common in patients with atypical symptoms during daily life (OR = 15.7) and in those on a therapeutic schedule of 5 days/week (OR = 9.44).ConclusionCapecitabine cardiotoxicity is frequent, and often elicited by physical effort. Oncologists, cardiologists, and general practitioners should be aware of this risk. Active cardiotoxicity surveillance with ECG (and echocardiogram and/or stress testing in suspected cases) during therapy is recommended.Clinical Trials registration numberCRO-2010-17.