Rapid Clinical and Radiologic Responses With Larotrectinib Treatment in a Patient With TRK-Fusion-Positive Metastatic Lung Cancer

Discovery of novel phenyl triazole analogs as TRK/ALK dual inhibitors with prospective antitumor effects

The exploration of novel anaplastic lymphoma kinase (ALK) and tropomyosin receptor kinase (TRK) dual inhibitors tended to serve as targeted treatment of cancer. Herein, a series of phenyl triazole derivatives were designed and synthesized as ALK/TRK dual regulators based on structure-based drug design (SBDD) strategy and were evaluated for antiproliferative activity by MTT assay. Accordingly, all compounds showed surprising cytotoxicity with IC₅₀ values below 10 μM on KM12, H2228 and KARPAS299 cell lines. Among them, compound 13a bearing (2-(4-methylpiperazin-1-yl)phenyl)morpholinomethanone moiety was identified as the optimal hit in enzymatic screening with IC₅₀ values of 1.9 nM (TRKA), 7.2 nM (ALK) and 65.2 nM (ALK^L1196M), respectively. Furthermore, 13a could inhibit KM12 cell migration and colony formation in a dose dependent manner. Meanwhile, AO/EB staining indicated that the pro-apoptotic effect of 13a was comparable to that of Entrectinib at the dose of 200 nM. Ultimately, the binding model of 13a with TRKA and ALK well established its mode of action which accounted for the superior activities as a promising antitumor candidate.

NTRK Gene Fusions in Solid Tumors and TRK Inhibitors: A Systematic Review of Case Reports and Case Series

The approval of larotrectinib and entrectinib for cancer patients harboring an NTRK gene fusion has represented a milestone in the era of "histology-agnostic" drugs. Among the clinical trials that led to the approval of these two drugs, most of the enrolled patients were affected by soft tissue sarcomas, lung, and salivary gland cancer. However, as next-generation sequencing assays are increasingly available in the clinical setting, health care professionals may be able to detect NTRK gene fusions in patients affected by tumor types under or not represented in the clinical trials. To this aim, we systematically reviewed MEDLINE from its inception to 31 August 2022 for case reports and case series on patients with NTRK gene fusion-positive tumors treated with TRK inhibitors. A virtual cohort of 43 patients was created, excluding those enrolled in the above-mentioned clinical trials. Although our results align with those existing in the literature, various cases of central nervous system tumors were registered in our cohort, confirming the benefit of these agents in this subgroup of patients. Large, multi-institutional registries are needed to provide more information about the efficacy of TRK inhibitors in cancer patients affected by tumor types under or not represented in the clinical trials.