Ideaya Biosciences Shares Surge on Dual Uveal Melanoma Breakthroughs
Ideaya Biosciences (Nasdaq: IDYA) made headlines on October 20, 2025, as two separate clinical data releases converged to paint a compelling picture of progress in the fight against uveal melanoma—a rare but aggressive eye cancer. The company’s stock closed at $29.26 on October 16, 2025, following a 52‑week high of $32.67 and a low of $13.45 earlier that year, underscoring heightened investor interest amid the recent findings.
1. Neoadjuvant Success at ESMO 2025
During a proffered oral presentation at the European Society for Medical Oncology (ESMO) 2025 conference, Ideaya disclosed Phase 2 data for darovasertib in the neoadjuvant setting of primary uveal melanoma. Key results include:
| Metric | Value | Interpretation |
|---|---|---|
| Tumor shrinkage | 83 % (78/94) | Indicates widespread efficacy of darovasertib before definitive surgery or radiotherapy |
| ≥20 % shrinkage | 54 % (51/94) | A substantial proportion achieved clinically meaningful responses |
| Enucleation‑preserving rate | 57 % (24/42) overall, rising to 95 % (19/20) among those with ≥20 % shrinkage | Suggests the drug may spare patients from eye‑removing surgery |
| Plaque brachytherapy (PB) eligibility | 70 % (26/37) saw reduced radiation doses | Lower predicted risk of vision loss at 3 years |
| Visual acuity improvement | ≈55 % (29/53) of EN‑eligible and ≈61 % (23/38) of PB‑eligible patients | Mean gains of 17 and 10 letters, respectively |
The data also reaffirmed darovasertib’s U.S. FDA Breakthrough Therapy Designation for neoadjuvant primary uveal melanoma in enucleation‑eligible patients, bolstering its regulatory standing.
2. First‑Line Combination Yields Survival Advantage
In a separate announcement at the Society for Melanoma Research (SMR) 2025 Congress, Ideaya reported Phase 1/2 trial results for a combination of darovasertib with Pfizer’s crizotinib in first‑line metastatic uveal melanoma (mUM). The OptimUM‑01 study produced:
- Median Overall Survival (OS): 21.1 months
vs. historical mOS ≈12 months in meta‑analyses - Median Progression‑Free Survival (PFS): 7.0 months
- Overall Response Rate (ORR) by RECIST 1.1: 34 %
- Median Duration of Response (mDOR): 9 months
- Disease Control Rate (DCR): 90 %
These figures suggest that the darovasertib–crizotinib pairing may substantially extend survival for patients who have traditionally faced a bleak prognosis.
3. Market Reaction and Analyst Sentiment
The day after the presentation of the Phase 2 data, Citizens JMP issued a bullish note on Ideaya, reflecting confidence in the company’s pipeline and clinical trajectory. Meanwhile, Investing.com highlighted the promising survival data from the metastatic study, noting that Ideaya’s market cap stands at $2.56 billion and its price‑to‑earnings ratio remains negative (‑7.44), indicative of the company’s continued investment‑heavy stage.
The confluence of these results has reinforced Ideaya’s position as a leading precision‑medicine oncology firm focused on small‑molecule therapeutics for cancer, specifically targeting biology pathways relevant to uveal melanoma. As the company moves toward potential regulatory submissions and further clinical milestones, stakeholders are watching closely for how these breakthroughs will translate into commercial success and shareholder value.
This article draws exclusively from publicly available press releases and financial reporting dated October 20, 2025, and associated market commentary.
