TYK Medicines, Inc. (Stock Code: 2410) presented early-phase clinical study findings for three cyclin-dependent kinase (CDK) inhibitor candidates—TYK-00540 (CDK2/4i), TY-2699a (CDK7i), and TY-302 (CDK4/6i)—at the European Society for Medical Oncology (ESMO) Congress 2025 in Berlin.

TYK-00540 (CDK2/4i) was evaluated in a Phase I dose-escalation study (NCT06950086). In 24 enrolled patients, 45.8% experienced Grade 3 or higher treatment-related adverse events, and 2 patients reported serious adverse events at Grade 3 or higher. Among 13 evaluable HR+/HER2- breast cancer cases, 2 achieved partial responses and 5 had stable disease, resulting in an ORR of 15.4% and a DCR of 53.8%. A 30 mg BID regimen was designated as the recommended dose. Further combination with fulvestrant continues, alongside promising preliminary outcomes in platinum-resistant ovarian cancer.

TY-2699a (CDK7i), a selective non-covalent inhibitor, was tested in a Phase I study (NCT05866692) using five dose-escalation cohorts. Twenty patients with advanced solid tumors participated, and three displayed stable disease. Continuous twice-daily administration allowed for relatively high dose levels, showcasing manageable safety and preliminary anti-tumor activity.

TY-302 (CDK4/6i) was examined in combination with toremifene in a Phase Ia/Ib study (NCT04433494). In 31 HR+/HER2- metastatic breast cancer patients receiving TY-302 (100 mg) plus toremifene, the overall response rate was 19.4%, the disease control rate was 77.4%, and median progression-free survival was 8.2 months.

There is no assurance of successful development, marketing, or commercialization of TYK-00540, TY-2699a, or TY-302. Shareholders and potential investors are advised to exercise caution when dealing in the shares of TYK Medicines, Inc.