IDEAYA Biosciences Inc（IDYA）のニュースとイベントIDYAIDEAYA Biosciences Inc

Ideaya Biosciences Updates Clinical Results for IDE849, Median OS of 17.4 Months in Second-Line SCLC

Ideaya Biosciences (IDYA) announced updated clinical results that show anti-tumor activity and preliminary overall survival results for IDE849, its investigational antibody-drug conjugate, or ADC, directed against delta-like ligand 3, or DLL3, and carrying a topoisomerase I, or TOP1, inhibitor payload. Ideaya Biosciences' partner, Jiangsu Hengrui Pharmaceuticals, is presenting the results from its Phase 1 study in China in relapsed small cell lung cancer, or SCLC, and other neuroendocrine carcinomas, or NECs, at the European Society for Medical Oncology, or ESMO, Congress 2026. The findings show substantial anti-tumor activity together with more mature PFS results and encouraging preliminary overall survival, including median overall survival of 17.4 months in the second-line SCLC setting. At the August 21 data cutoff, 122 patients had enrolled, including 103 with SCLC and 19 with other NECs at IDE849 doses greater than or equal to1.8 mg/kg IV dosed once every 3-weeks, or Q3W. Median follow-up was 12.1 months. Among patients with SCLC, 78.6% had received prior immunotherapy, 49.5% had one prior line of therapy, and 50.5% were heavily pre-treated having received two or more prior lines of treatment. In second-line SCLC, median OS was 17.4 months, and median PFS was 6.9 months. Across previously treated SCLC patients receiving doses greater than or equal to1.8 mg/kg, median OS was 14.7 months and median PFS was 6.8 months. The survival analyses included 55 OS events and 86 PFS events. In patients with brain metastases, confirmed ORR was 65.4%, with disease control observed in all 26 patients. The longer follow-up provides a more mature assessment of progression free survival, or PFS, and the first assessment of preliminary OS reported from the study. The WCLC 2025 analysis had a median follow-up of 3.5 months and reported median PFS of 6.7 months in previously treated SCLC, with median PFS not yet reached in the second-line setting. The ESMO update includes a larger population and patients treated at doses greater than or equal to1.8 mg/kg Q3W. Among 19 patients with other NECs, ORR was 52.6%, confirmed ORR was 36.8% and disease control rate was 84.2%. Median PFS was 7.0 months and the nine-month OS rate was 82.4%, supporting further evaluation beyond SCLC. High DLL3 expression has been reported across multiple solid tumor subtypes of NECs that remain areas of high unmet medical need with few treatment options, including gastroenteropancreatic neuroendocrine carcinoma and large cell neuroendocrine carcinoma. The projected annual incidence of GEP-NEC and LC-NEC globally in the metastatic setting, is projected to be approximately 40,000 patients and 30,000 patients, respectively. In the major market countries of the US, EU5, and Japan, the GEP-NEC and LC-NEC metastatic annual incidence is projected to be approximately, 7,000 patients and 8,000 patients, respectively. There are multiple additional subtypes of NECs that have high DLL3 expression, including bladder and cervical, among others. At the expansion dose of 2.4 mg/kg, the most common treatment-related adverse events were neutrophil count decrease, white blood cell count decrease, and anemia. At the 2.4 mg/kg expansion dose, the Grade 3 or higher treatment-related adverse events, or TRAEs, occurred in 33.3% of patients and the serious TRAEs occurred in 15.2% of patients. The investigators reported a safety profile comparable to that observed previously and reported at the WCLC in 2025. Across all 122 patients and all dose levels, the most common Grade 3 or higher TRAEs were hematologic. Across the dose escalation, Grade 3 or higher TRAEs occurred in 59.8% of patients, and serious TRAEs occurred in 21.3%. TRAEs led to dose reductions in 18.9% and treatment discontinuation in 2.5% of patients. One treatment-related death due to pneumonia was reported, which is the same patient that was reported at WCLC 2025. Across the study, Grade 1 to 2 interstitial lung disease was observed in 6.6% of patients and Grade greater than or equal to 3 ILD in 0.8%. Ideaya 's separate ongoing Phase 1/2 global study of IDE849 in extensive-stage SCLC and NEC is enrolling patients in the Americas, Europe, and Asia. The company is evaluating several expansion doses to determine the recommended Phase 3 dose, including 2.4 mg/kg and 3.5 mg/kg IV Q3W. As of an October 1 data cut-off, a Grade greater than or equal to3 TRAE rate of 5% at 2.4 mg/kg and 22.2% at 3.5 mg/kg have been observed. The most common adverse events were hematologic, including neutropenia, white blood cell count decrease, and anemia, and the maximum tolerated dose was determined to be 4.2 mg/kg. Ideaya is targeting to provide a clinical efficacy and safety update from the global Phase 1/2 trial of IDE849 monotherapy by the end of 2026 or early in 2027, with a focus on post-Imdelltra ES-SCLC and relapsed NEC. Based on successful Type C meetings with the FDA, Ideaya is targeting to initiate two randomized global Phase 3 registrational trials with IDE849 in ES-SCLC and NEC. The company is also evaluating a potential trial design for a Phase 3 registrational trial in 1L SCLC, pending data from its Phase 1 combination cohorts with IDE161 and Astra Zeneca's (AZN) PD-L1 antibody, durvalumab.

Ideaya Biosciences Updates Darovasertib Clinical Data

Ideaya Biosciences announced updated clinical data from three ongoing studies evaluating darovasertib in metastatic and primary uveal melanoma, or UM, that will be presented at the European Society for Medical Oncology, or ESMO, Congress 2026, taking place on October 23-27 in Madrid, Spain. The updates will include Phase 2 expansion data from OptimUM-01 in HLA-A02:01-positive patients with metastatic uveal melanoma, or mUM, subgroup analyses from the registrational Phase 2/3 OptimUM-02 trial in first line, or 1L, HLA-A02:01-negative mUM and follow-up data from the Phase 2 OptimUM-09 trial evaluating neoadjuvant darovasertib in patients with primary UM. The combination demonstrated a profile across key measures of efficacy, including overall response rate, or ORR, disease control rate, or DCR, duration of response, or DOR, progression free survival, or PFS, and overall survival, or OS. Based on data from large meta-analyses published by Khoja and Rantala it has been shown that mUM has an especially poor prognosis, with a reported median PFS of 2.8 months and median OS of 12 months in the treatment-na ve setting. In the 2L setting, median PFS remains at 2-3 months but median OS drops to 8 months with a 1-year OS rate of 37%. As shown in the table above the data from OptimUM-01 compares favorably to these historical PFS and OS benchmarks, as well as to historical ORR which is typically 5%. Safety was manageable and generally consistent with previously reported results, with the most common treatment-related adverse events of diarrhea, nausea, peripheral edema, and vomiting. Related adverse events leading to treatment discontinuation occurred in 9 participants. Ideaya reported results from OptimUM-02 at the American Society of Clinical Oncology, or ASCO, demonstrating that 1L HLA A02:01 -negative mUM patients treated with the darovasertib combination had a median PFS of 6.9 months by blinded independent central review, or BICR, and 6.7 months by investigator assessment, compared to 3.1 months and 2.7 months in the investigator's choice of therapy, or ICT, control arm, respectively. The ESMO data builds on these results, showing consistent improvements in ORR and PFS compared to ICT across multiple clinically relevant subgroups, including baseline lactate dehydrogenase, or LDH, levels, ECOG performance status, largest target lesion size and choice of ICT used in the control arm. As expected, patients with higher tumor burden had a worse prognosis, however outcomes were still better with the darovasertib combination compared to ICT. OptimUM-09 is a Phase 2 trial evaluating single-agent darovasertib before local treatment in patients with primary uveal melanoma requiring enucleation, or surgical removal of the eye, or plaque brachytherapy. The primary endpoints for these cohorts are eye preservation rate and planned radiation dose reduction, respectively. The data in the ESMO abstract was from 116 patients treated with neoadjuvant darovasertib, including 66 patients in Cohort 1 and 50 patients in Cohort 2, as of a cutoff date of February 23, 2026, and is described below. However, the updated data to be presented at ESMO is from a total of 119 patients as of a cutoff date of June 15, 2026. Nonetheless, the data is largely consistent and continues to support the previously reported results from the trial, including at ESMO in 2025.

IDEAYA Biosciences Promotes Michael White to President, Research and Development

IDEAYA Biosciences announced the promotion of Dr. Michael White, from Chief Scientific Officer to President, Research and Development. White has served as CSO since 2021.