Goyal L, DiToro D, Facchinetti F, Martin E E, Peng P, Baiev I, Iyer R, Maurer J, Reyes S, Zhang K, Majeed U, Berchuck J E, Chen C T, Walmsley C, Pinto C, Vasseur D, Gordan J D, Mody K, Borad M, Karasic T, Damjanov N, Danysh B P, Wehrenberg-Klee E, Kambadakone A R, Saha S K, Hoffman I D, Nelson K J, Iyer S, Qiang X, Sun C, Wang H, Li L, Javle M, Lin B, Harris W, Zhu A X, Cleary J M, Flaherty K T, Harris T, Shroff R T, Leshchiner I, Parida L, Kelley R K, Fan J, Stone J R, Uboha N V, Hirai H, Sootome H, Wu F, Bensen D C, Hollebecque A, Friboulet L, Lennerz J K, Getz G, Juric D
Department of Medicine, Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, USA; Department of Medicine, Stanford Cancer Center, Stanford University School of Medicine, Palo Alto, USA.
Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, USA.
Ann Oncol. 2025 Apr;36(4):426-443. doi: 10.1016/j.annonc.2024.12.011. Epub 2024 Dec 18.
Fibroblast growth factor receptor (FGFR) inhibitors have significantly improved outcomes for patients with FGFR-altered cholangiocarcinoma, leading to their regulatory approval in multiple countries. As with many targeted therapies, however, acquired resistance limits their efficacy. A comprehensive, multimodal approach is crucial to characterizing resistance patterns to FGFR inhibitors.
This study integrated data from six investigative strategies: cell-free DNA, tissue biopsy, rapid autopsy, statistical genomics, in vitro and in vivo studies, and pharmacology. We characterized the diversity, clonality, frequency, and mechanisms of acquired resistance to FGFR inhibitors in patients with FGFR-altered cholangiocarcinoma. Clinical samples were analyzed longitudinally as part of routine care across 10 institutions.
Among 138 patients evaluated, 77 met eligibility, yielding a total of 486 clinical samples. Patients with clinical benefit exhibited a significantly higher rate of FGFR2 kinase domain mutations compared with those without clinical benefit (65% versus 10%, P < 0.0001). We identified 26 distinct FGFR2 kinase domain mutations, with 63% of patients harboring multiple. While IC50 assessments indicated strong potency of pan-FGFR inhibitors against common resistance mutations, pharmacokinetic studies revealed that low clinically achievable drug concentrations may underly polyclonal resistance. Molecular brake and gatekeeper mutations predominated, with 94% of patients with FGFR2 mutations exhibiting one or both, whereas mutations at the cysteine residue targeted by covalent inhibitors were rare. Statistical genomics and functional studies demonstrated that mutation frequencies were driven by their combined effects on drug binding and kinase activity rather than intrinsic mutational processes.
Our multimodal analysis led to a model characterizing the biology of acquired resistance, informing the rational design of next-generation FGFR inhibitors. FGFR inhibitors should be small, high-affinity, and selective for specific FGFR family members. Tinengotinib, a novel small molecule inhibitor with these characteristics, exhibited preclinical and clinical activity against key resistance mutations. This integrated approach offers a blueprint for advancing drug resistance research across cancer types.
成纤维细胞生长因子受体（FGFR）抑制剂显著改善了FGFR改变的胆管癌患者的治疗效果，已在多个国家获得监管批准。然而，与许多靶向治疗一样，获得性耐药限制了它们的疗效。采用全面的多模式方法对于明确FGFR抑制剂的耐药模式至关重要。
本研究整合了六种研究策略的数据：游离DNA、组织活检、快速尸检、统计基因组学、体外和体内研究以及药理学。我们明确了FGFR改变的胆管癌患者对FGFR抑制剂获得性耐药的多样性、克隆性、频率及机制。作为10个机构常规护理的一部分，对临床样本进行了纵向分析。
在评估的138例患者中，77例符合条件，共获得486份临床样本。与无临床获益的患者相比，有临床获益的患者FGFR2激酶结构域突变率显著更高（65%对10%，P<0.0001）。我们鉴定出26种不同的FGFR2激酶结构域突变，63%的患者携带多种突变。虽然IC50评估表明泛FGFR抑制剂对常见耐药突变具有强效，但药代动力学研究显示，临床可达到的低药物浓度可能是多克隆耐药的基础。分子制动和守门人突变占主导，94%的FGFR2突变患者表现出其中一种或两种突变，而共价抑制剂靶向的半胱氨酸残基突变很少见。统计基因组学和功能研究表明，突变频率是由它们对药物结合和激酶活性的综合影响驱动的，而不是由内在突变过程驱动的。
我们的多模式分析得出了一个描述获得性耐药生物学特性的模型，为下一代FGFR抑制剂的合理设计提供了依据。FGFR抑制剂应体积小、亲和力高且对特定FGFR家族成员具有选择性。替奈替尼是一种具有这些特性的新型小分子抑制剂，对关键耐药突变表现出临床前和临床活性。这种综合方法为推进各类癌症的耐药性研究提供了蓝图。
