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]

Summary of IDEAYA Biosciences (IDYA) 2025 Conference Call Company Overview - IDEAYA Biosciences is celebrating its 10-year anniversary in 2025, positioning itself for a transformational year with its lead program, drovosertib, targeting metastatic melanoma [4][5][6] Key Developments and Pipeline Updates - **Drovosertib**: - Anticipated readout for the frontline metastatic melanoma study in HLA A2 negative patients by year-end 2025 [4] - Phase two study to report median overall survival data for over 40 patients, including both HLA A2 negative and positive [5] - Additional data readouts planned for neoadjuvant uveal melanoma studies in mid and late 2025 [6] - **Clinical Trials**: - Enrollment for the randomized PFS readout has exceeded the required number, with over 300 patients enrolled [12] - Historical PFS data suggests a target of over 5.5 months for accelerated approval, with previous studies showing approximately 7 months [14][15] - The objective for overall survival (OS) is ideally 6 months or greater, with historical OS in the range of 12-13 months [16][17] - **Commercialization Strategy**: - Focus on HLA A2 negative population for initial accelerated approval, with plans to include HLA A2 positive data in NDA submission [20][21] - Estimated annual incidence of metastatic uveal melanoma is approximately 45,000 patients [23] Neoadjuvant Setting - FDA granted breakthrough therapy designation for the neoadjuvant setting, indicating strong potential for the treatment [28] - Eye preservation rate currently exceeds 50%, significantly above the target of 10% [29] - Upcoming data will include simulated visual prediction and actual vision outcomes from neoadjuvant treatment [30][31] Pipeline Expansion - IDEAYA is working on multiple clinical programs, with a goal of having nine clinical programs by year-end [8] - DLL3 ADC in Phase one shows a response rate of over 70%, with plans for further studies in small cell lung cancer [47][48] - PRMT5 inhibitor and Werner helicase inhibitor are also in development, with IND submissions expected soon [56][57] Market Insights - Uveal melanoma primarily affects Caucasian populations, with a need for approved therapies in both metastatic and premetastatic settings [36][37] - The company is focused on understanding the epidemiology and total prevalence of uveal melanoma to better target its therapies [36][37] Conclusion - IDEAYA Biosciences is poised for significant developments in 2025, with multiple data readouts and a strong focus on commercialization strategies for its lead assets in precision oncology [58][59]

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) 5000 Shoreline Court, Suite 300 South San Francisco, California 94080 (Address of principal executive offices) (Zip Code) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES AND EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 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: 0 ...

Exhibit 99.1 IDEAYA Biosciences, Inc. Reports First Quarter 2025 Financial Results and Provides Business Update SOUTH SAN FRANCISCO, Calif., May 6, 2025 -- IDEAYA Biosciences, Inc. (Nasdaq: IDYA), a precision medicine oncology company committed to the discovery and development of targeted therapeutics, provided a business update and announced financial results for the first quarter that ended March 31, 2025. "We have provided an updated cash runway guidance into 2029, and this past quarter we made significa ...

Core Insights - IDEAYA Biosciences, Inc. provided a business update and announced financial results for Q1 2025, highlighting significant progress in its clinical programs and financial position [1][2]. Financial Overview - As of March 31, 2025, IDEAYA had approximately $1.05 billion in cash, cash equivalents, and marketable securities, down from $1.08 billion at the end of 2024, primarily due to operational cash usage [4][16]. - The company projects that its current cash balance will fund operations into 2029 based on its updated operating plan [17]. - The net loss for Q1 2025 was $72.2 million, a decrease from a net loss of $130.3 million in Q4 2024 [22]. Clinical Development Highlights - The darovasertib program received U.S. FDA breakthrough therapy designation, with over 300 patients enrolled in the registrational trial for HLA-A2-negative metastatic uveal melanoma (MUM) [2][4]. - The company is targeting a median progression-free survival (PFS) readout by the end of 2025 to enable a potential accelerated approval filing [4][5]. - IDEAYA is advancing multiple clinical programs, including IDE849 for lung cancer, IDE275 for MSI-high colorectal and endometrial cancer, and IDE397 for MTAP-deletion lung and urothelial cancer [2][4]. Research and Development Updates - The Phase 3 trial for darovasertib as neoadjuvant therapy for primary uveal melanoma is expected to enroll approximately 520 patients, with a focus on eye preservation and visual acuity outcomes [5][6]. - IDEAYA plans to present clinical data updates at medical conferences throughout 2025, including results from darovasertib and other pipeline candidates [4][5]. - The company has initiated a Phase 1 study for IDE849 in small cell lung cancer (SCLC) and is collaborating with Gilead to evaluate IDE397 in combination with Trodelvy® [12][19]. Corporate Developments - IDEAYA appointed Joshua Bleharski as Chief Financial Officer and Shanthakumar Tyavanagimatt as Senior Vice President of Technical Operations, enhancing its leadership team [21]. - The company formed a collaboration with ATTMOS to develop a computational platform for small molecule discovery, aiming to unlock oncology targets [21].

"IDE849 is a potential first-in-class DLL3 TOP1 ADC, a target antigen that has demonstrated preliminary monotherapy clinical validation in SCLC. In addition, IDE849 aligns with our strategy to develop rational combination therapies, particularly with our potential first-in-class Phase 1 PARG inhibitor IDE161, where we have generated preclinical combination data with TOP1-based ADCs that demonstrates combination synergy and enhanced durability," said Dr. Darrin M. Beaupre, M.D., Ph.D., Chief Medical Officer, ...