#United States #IDEAYA Biosciences #South San Francisco #uveal melanoma #darovasertib

IDEAYA Biosciences Presents Phase 2 Data for Darovasertib in Uveal Melanoma

On October 20, 2025, IDEAYA Biosciences, Inc. (NASDAQ IDYA), a company focused on precision medicine in oncology, made significant strides in the fight against primary uveal melanoma with the unveiling of positive results from their Phase 2 OptimUM-09 trial at the European Society of Medical Oncology (ESMO) congress in Berlin, Germany. The presentation was led by Dr. Marcus Butler, an esteemed Associate Professor at the Princess Margaret Cancer Center, University of Toronto.

This groundbreaking trial assessed the efficacy of Darovasertib as a neoadjuvant treatment for primary uveal melanoma—a condition with no currently approved systemic therapies available. This study aimed to address the pressing need for options that could reduce the probability of eye removal while potentially curbing the risk of metastatic disease.

Key Findings of the OptimUM-09 Trial

The data derived from a total of 95 patients diagnosed with primary uveal melanoma, revealing impressive outcomes:

• - Tumor Shrinkage: An astonishing 83% (78 out of 94) of the participants experienced ocular tumor reduction. Notably, 54% of these patients showed a shrinkage of 20% or more.
• - Eye Preservation Rates: Among patients recommended for enucleation (Cohort 1), the eye preservation rate was recorded at 57% (24 out of 42). Impressively, this figure surged to 95% for those achieving the aforementioned tumor reduction threshold.
• - Reduction in Radiation Dosage: For patients eligible for plaque brachytherapy (Cohort 2), approximately 70% (26 out of 37) exhibited a reduction in predicted radiation dose to critical eye structures.
• - Visual Acuity Improvements: Visual acuity scores notably improved during treatment, with 55% (29 out of 53) of those in Cohort 1 and 61% (23 out of 38) in Cohort 2 demonstrating increased scores from baseline, translating to meaningful gains in vision.

The Therapeutic Promise of Darovasertib

Darrin Beaupre, Chief Medical Officer at IDEAYA, expressed optimism regarding the trial results. He noted that the outcome demonstrates the potential of Darovasertib in achieving significant tumor shrinkage and eye preservation, thus potentially establishing it as the first systemic treatment for this condition.
According to Dr. Butler, the results of the OptimUM-09 trial could significantly alter the therapeutic landscape for patients requiring enucleation or plaque brachytherapy, offering them a viable path to preserve both their eyesight and eye structure by utilizing a single treatment approach.

Safety and Tolerability

The trial also examined the safety profile of Darovasertib, which was found to be generally well tolerated among participants. Adverse effects were minimal, primarily low-grade events such as diarrhea and fatigue, with only 16.8% (16 out of 95) experiencing severe treatment-related adverse events.

Looking Forward

IDEAYA is now gearing up for a Phase 3 trial named OptimUM-10 that will evaluate Darovasertib as a single-agent treatment in the neoadjuvant setting. The company is also keen on reporting median progression-free survival data from its registration-enabling Phase 2/3 trial (OptimUM-02) before the end of 2025. This data will be vital in potentially pursuing accelerated approval for Darovasertib in conjunction with crizotinib in the treatment of advanced uveal melanoma.

About IDEAYA Biosciences

IDEAYA is dedicated to leveraging cutting-edge research into therapeutic innovations for cancer treatment. Their focus on synthetic lethality, antibody-drug conjugates, and the integration of precision medicine principles aims to offer unique, targeted therapies that can dramatically alter the trajectory of cancer treatment. With a commitment to developing breakthrough solutions, IDEAYA aims to significantly improve outcomes for patients suffering from various cancer types.