Core Insights - IDEAYA Biosciences, Inc. is hosting an in-person R&D Day on September 8, 2025, in New York to celebrate its 10-Year Anniversary and discuss its progress and future growth strategy [1][2]. Company Overview - IDEAYA is a precision medicine oncology company focused on discovering and developing targeted therapeutics for cancer, integrating small-molecule drug discovery, structural biology, and bioinformatics [6]. R&D Day Agenda - The R&D Day will feature presentations on new clinical data for darovasertib in neoadjuvant uveal melanoma, IDE849 (DLL3 TOP1 ADC), and IDE397 (MAT2A) [2][8]. - Dr. Arun D. Singh from the Cleveland Clinic will present data from the Phase 2 trial of darovasertib and discuss the Phase 3 OptimUM-10 trial [4]. - The agenda includes discussions on various drug candidates, including initial Phase 1 clinical data for IDE397/Trodelvy combination in MTAP-deletion urothelial cancer and the application of AI/ML in discovery capabilities [8].

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES AND EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2025 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES AND EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38915 IDEAYA Biosciences, Inc. (Exact name of registrant as specified in its charter) FORM 10-Q (Mark One) 5000 Shoreline Court, Suite 300 So ...

Exhibit 99.1 IDEAYA Biosciences, Inc. Reports Second Quarter 2025 Financial Results and Provides Business Update SOUTH SAN FRANCISCO, Calif., August 5, 2025 /PRNewswire/ -- IDEAYA Biosciences, Inc. (Nasdaq: IDYA), an oncology company committed to advancing the discovery, development, and commercialization of transformative precision medicines to address unmet medical needs in cancer, provided a business update and announced financial results for the second quarter ended June 30, 2025. Darovasertib • Metasta ...

Core Insights - IDEAYA Biosciences announced that results from a global Phase 2 study of neoadjuvant darovasertib in primary uveal melanoma will be presented at the 2025 ESMO meeting in Berlin [1][2] - The presentation will focus on the effects of darovasertib across plaque brachytherapy and enucleation cohorts, highlighting its potential impact on disease management [2][3] - The company has initiated a randomized Phase 3 neoadjuvant registrational trial (OptimUM-10) for darovasertib in primary uveal melanoma [6] Company Overview - IDEAYA Biosciences is a precision medicine oncology company focused on developing transformative therapies for cancer [3] - The company integrates drug discovery, structural biology, and bioinformatics to create targeted therapies for specific patient populations [3] - IDEAYA has a robust pipeline that includes therapies based on synthetic lethality and antibody-drug conjugates [3] Clinical Study Details - The upcoming presentation will include data from over 90 patients in both plaque brachytherapy and enucleation-eligible cohorts [6] - Darovasertib has received U.S. FDA Breakthrough Therapy Designation for neoadjuvant use in uveal melanoma patients requiring enucleation [6]

Core Insights - IDEAYA Biosciences, Inc. will host an in-person and virtual R&D Day on September 8, 2025, to present clinical data updates and discuss growth drivers and upcoming milestones [1][2] - The event will feature members of IDEAYA's senior leadership team and key opinion leaders [3] - IDEAYA is celebrating its ten-year anniversary and aims to highlight its strategic vision and emerging clinical pipeline [2] Company Overview - IDEAYA is a precision medicine oncology company focused on discovering, developing, and commercializing transformative therapies for cancer [4] - The company integrates small molecule drug discovery, structural biology, and bioinformatics to develop potentially first-in-class targeted therapies [4] - IDEAYA has a robust pipeline that includes targeted therapies focused on synthetic lethality and antibody-drug conjugates (ADCs) [4]

Core Insights - IDEAYA Biosciences and Jiangsu Hengrui Pharmaceuticals announced an oral presentation on IDE849 (SHR-4849) at the IASLC 2025 World Conference on Lung Cancer, focusing on its efficacy and safety in small-cell lung cancer (SCLC) patients [1][3] - IDE849 is a potential first-in-class DLL3-targeting Topoisomerase-1 (TOP1) payload antibody drug conjugate (ADC), addressing significant unmet medical needs in various solid tumors [1][3] Group 1: Presentation Details - The oral presentation will take place on September 7, 2025, from 4:45-6:00 PM (CET) and will cover a Phase 1 study of SHR-4849 (IDE849) in relapsed SCLC [4] - A poster presentation will also be held on September 8, 2025, discussing the combination mechanism and pre-clinical synergy data between TOP1-payload based ADCs and IDE161, a proprietary PARG inhibitor [2][5] Group 2: Clinical Development - The Phase 1 trial for IDE849 is ongoing in China, with data from over 70 SCLC patients expected to be presented, including results from dose escalation and multiple expansion doses [6] - The U.S. Phase 1 trial of IDE849 in SCLC patients was initiated in the third quarter of 2025 [6] Group 3: Company Strategy - IDEAYA aims to evaluate rational combinations of therapies to improve clinical outcomes for cancer patients, including the use of IDE849 as a monotherapy and in combination with immunotherapy and IDE161 [2][3] - The company has a robust pipeline focused on synthetic lethality and ADCs, including bispecifics, to address unmet medical needs in cancer [7]

Group 1 - IDEAYA Biosciences, Inc. is participating in the 2025 BTIG Virtual Biotechnology Conference on July 29, 2025, at 4:40 PM ET, featuring a fireside chat with CEO Yujiro S. Hata [1] - The conference will be accessible via a live audio webcast on the IDEAYA website, with a replay available for 30 days post-event [1] Group 2 - IDEAYA is focused on precision medicine in oncology, aiming to discover, develop, and commercialize transformative therapies for unmet medical needs in cancer [2] - The company integrates small molecule drug discovery, structural biology, and bioinformatics to develop targeted therapies, including synthetic lethality and antibody-drug conjugates (ADCs) [2] - IDEAYA has established a robust pipeline of targeted therapies aimed at improving clinical outcomes for cancer patients [2]

Summary of IDEA Biosciences Conference Call Company Overview - **Company**: IDEA Biosciences - **Focus**: Development of innovative therapies for cancer treatment, with six clinical programs currently and a target of nine by year-end [2][1]. Key Value Drivers - **Lead Program**: Derobicertib, targeting metastatic human melanoma, currently in a registrational trial [2][1]. - **Enrollment Status**: Completed enrollment for the trial, with over 320 patients enrolled, exceeding the target of 250 [12][13]. - **Primary Endpoint**: Median progression-free survival (PFS) is crucial for potential accelerated approval, with historical PFS around 2-3 months and a target of over 5.5 months for the current study [3][8]. Clinical Data and Updates - **PFS Results**: Previous studies showed a PFS of approximately 7 months, with a specific setting achieving nearly 11 months [10][11]. - **Overall Survival (OS)**: Anticipated update on OS data from the phase two study, with historical OS in treatment-naive settings around 12-13 months [17][18]. - **Market Opportunity**: Targeting the HLA A2 negative population, with an estimated annual incidence of 4,000 to 5,000 patients in the US and Europe [20][19]. Commercial Strategy - **Commercial Organization**: Building a commercial team with key hires, including a Chief Commercial Officer and heads of various departments [24][25]. - **Regulatory Strategy**: Fast track designation from the FDA for expedited review, with ongoing discussions regarding NDA submission [14][16]. Pipeline and Future Developments - **Additional Programs**: Focus on MTAP deletion space and DLL3, with several data catalysts expected [5][6][51]. - **Combination Therapies**: Emphasis on rational combinations, particularly with PRMT5 inhibitors in lung cancer [70][71]. - **IND Filings**: Targeting multiple INDs, with a goal of one IND per year, and a record of four INDs planned for the current year [86][87]. Financial Position - **Cash Reserves**: Reported over $1 billion in cash, providing a strong financial position for ongoing and future clinical activities [88][87]. Conclusion - IDEA Biosciences is positioned for significant growth with multiple clinical programs, a robust commercial strategy, and a strong financial foundation, aiming to address unmet needs in cancer treatment through innovative therapies and strategic partnerships.

Summary of IDEAYA Biosciences (IDYA) Conference Call Company Overview - IDEAYA Biosciences is a leading precision medicine oncology company founded about a decade ago with six clinical programs and a target of nine by the end of the year [4][5] Key Clinical Programs - **Durovacertib**: Currently in a pivotal registration enabling trial targeting frontline approval in HLA A2 negative metastatic melanoma, with a potential readout for accelerated approval by year-end based on median progression-free survival (PFS) [5][7] - **Clinical Data**: Historical median PFS in metastatic uveal melanoma is 2-3 months; IDEAYA reported a median PFS of approximately 7 months at ESMO 2023, aiming for a PFS of over 5.5 months in their study [7][21] - **Enrollment**: Target enrollment for the PFS study was 250 patients, but over 320 patients have been enrolled, with expectations to complete full enrollment by year-end [9][10] Upcoming Data and Regulatory Plans - **OS Readout**: The overall survival (OS) readout is expected to occur concurrently with the PFS readout, with preliminary data anticipated by mid-2026 [14][15] - **NDA Filing**: Fast track designation in the metastatic setting and breakthrough therapy designation in the neoadjuvant setting will facilitate NDA submission post-results [19][20] Market Opportunity - **HLA A2 Negative Population**: The company sees a significant commercial opportunity in the HLA A2 negative patient population, with approximately 70% of screened patients being HLA A2 negative [26][29] - **Chemtrac Comparison**: Chemtrac from Immunocor has shown strong growth with a run rate of $375 million, indicating a robust market potential for IDEAYA's products [26] Neoadjuvant Study - **Phase III Study Design**: The study includes two cohorts (enucleation and plaque therapy) with primary endpoints focused on eye preservation and vision tests, respectively [34][35] - **Enrollment Timeline**: Anticipated enrollment of 520 patients over five quarters, with the first readout expected within a year [38][40] DLL3 Topical ADC - **Differentiation**: IDEAYA's DLL3 ADC is expected to differentiate based on its tetrapeptide cleavable linker, which cleaves upon internalization, compared to competitors [49][50] - **Data Expectations**: A medical conference update is expected in the third quarter, with data on response rates and adverse event profiles [51][56] MAT2A Inhibitor and Combination Studies - **Combination with Trodelvy**: IDEAYA is optimistic about achieving a response rate above 40% in combination studies with Gilead's Trodelvy in urothelial carcinoma [65] - **PRMT5 Inhibitor**: The company plans to submit an IND for a combination therapy with its PRMT5 inhibitor, aiming for greater response rates compared to monotherapy [67][70] Financial Position - **Cash Reserves**: As of March, the company reported over $1 billion in cash, providing runway into 2029 and flexibility for continued investment in its pipeline [78][79] Upcoming Catalysts - **Data Readouts**: IDEAYA anticipates four data readouts for durovacertib and a substantial update on DLL3 in the third quarter, along with plans for an R&D day by year-end [82][83]

Group 1 - IDEAYA Biosciences, Inc. is participating in two upcoming investor relations events: the 2025 Jefferies Global Healthcare Conference on June 4th and the Goldman Sachs 46th Annual Global Healthcare Conference on June 9th [1] - The CEO, Yujiro S. Hata, will be featured in fireside chats at both conferences, hosted by equity research analysts from Jefferies and Goldman Sachs [1] - A live audio webcast of the events will be available on the IDEAYA website, with replays accessible for 30 days post-event [1] Group 2 - IDEAYA is focused on precision medicine in oncology, developing targeted therapeutics based on molecular diagnostics [2] - The company integrates capabilities in identifying and validating translational biomarkers with drug discovery to optimize patient selection for its therapies [2] - IDEAYA is particularly focused on synthetic lethality, an emerging class of precision medicine targets [2]