IDEAYA Biosciences, Inc. Reports Fourth Quarter and Full Year 2024 Financial Results

and Provides Business Update

South San Francisco, CA, February 13, 2025– IDEAYA Biosciences, Inc. (Nasdaq: IDYA), a precision medicine oncology company committed to the discovery and development of targeted therapeutics, announced financial results for the quarter and full year ended December 31, 2024, and provided a business update.

“We are excited to be targeting multiple clinical data readouts and program updates across our clinical pipeline in 2025, including the darovasertib neoadjuvant UM data update in the first half and median PFS readout in HLA-A2 negative 1L MUM by year-end, update on the Werner Helicase inhibitor program IDE275 at a major medical conference in the first half, clinical combination results from the IDE397 and Trodelvy combination in MTAP-deletion UC where the Gilead collaboration has expanded to evaluate both UC and NSCLC, among others. Next, we are excited to target a clinical data update for potential first-in-class DLL3 TOP1 ADC IDE849 in SCLC in 2025, including potentially at a medical conference, and we believe the clinical profile observed supports a potential monotherapy regulatory path in SCLC,” said Yujiro S. Hata, President and Chief Executive Officer, IDEAYA Biosciences.

“We had multiple positive clinical updates across our pipeline throughout the past year that were presented at major medical conferences, including compelling results such as tumor shrinkage and eye preservation for neoadjuvant darovasertib which was presented as an oral presentation at ASCO 2024, and evidence for monotherapy activity with IDE397 which delivered a high disease control rate and multiple confirmed RECIST 1.1 responses in MTAP-deletion lung and urothelial cancer, which was presented as a late breaker oral presentation at ENA 2024. Next, we believe we have generated important proof-of-concept preclinically and preliminary clinical data for the MAT2A and PRMT5 combination in the MTAP-deletion setting and are excited to advance IDEAYA’s wholly-owned IDE397 and IDE892 combination that we are targeting to have in the clinic in the second half of 2025,” commented Darrin Beaupre, M.D., Ph.D., Chief Medical Officer, IDEAYA Biosciences. “Additionally, in the last several quarters we made significant progress in enhancing our potential first-in-class clinical pipeline with the in-licensing of the Phase 1 DLL3 TOP1i ADC IDE849 and FDA clearance of the Phase 1 trial for the Werner Helicase inhibitor IDE275. We are also advancing three programs into IND-enabling studies: our PRMT5 inhibitor IDE892, the B7H3/PTK7 ADC IDE034 and a KAT6/7 inhibitor IDE251,” said Michael White, Ph.D., Chief Scientific Officer, IDEAYA Biosciences.

Recent Key Developments and Upcoming Milestones

Research and Clinical Development

Corporate Development

Financial Results

As of December 31, 2024, IDEAYA had cash, cash equivalents and marketable securities of approximately $1.1 billion, compared to $632.6 million as of December 31, 2023. The increase was primarily driven from $379.9 million in net proceeds from the sale of common stock shares through at-the-market financings during the year, $283.8 million from an underwritten public offering of common stock and pre-funded warrants to purchase common stock completed in July 2024, partially offset by net cash used in operations. IDEAYA believes that these funds will be sufficient to fund its planned operations into at least 2028.

Subsequent to the reporting period for the year ended December 31, 2024, the Company generated net proceeds of approximately $25.1 million from the sale of shares of its common stock through at-the-market (ATM) offerings in January 2025.

Collaboration revenue for the three months ended December 31, 2024 totaled $7.0 million compared to $3.9 million for the three months ended December 31, 2023. Collaboration revenue was recognized for a $7.0 million milestone payment from GSK that was earned for the IND clearance of IDE275 (GSK959) in October 2024.

Research and development (R&D) expenses for the three months ended December 31, 2024, totaled $140.2 million compared to $38.8 million for the three months ended December 31, 2023. The increase was primarily due to a $75.0 million upfront payment under the license agreement for IDE849 with Hengrui Pharma, higher clinical trial expenses to support the portfolio growth and personnel-related expenses.

General and administrative (G&A) expenses for the three months ended December 31, 2024 totaled $11.0 million compared to $7.1 million for the three months ended December 31, 2023. The increase was primarily due to higher personnel-related expenses, higher consulting and legal fees.

The net loss for the three months ended December 31, 2024, was $130.3 million compared to the net loss of $34.0 million for the three months ended December 31, 2023. Total stock compensation expense for the three months ended December 31, 2024, was $9.5 million compared to $4.8 million for the same period in 2023.

The net loss for the year ended December 31, 2024 was $274.5 million compared to $113.0 million for the same period in 2023. Total stock compensation expense for the year ended December 31, 2024, was $34.7 million compared to $18.5 million for the same period in 2023.

About IDEAYA Biosciences

IDEAYA is a precision medicine oncology company committed to the discovery and development of targeted therapeutics for patient populations selected using molecular diagnostics. IDEAYA's approach integrates capabilities in identifying and validating translational biomarkers with drug discovery to select patient populations most likely to benefit from its targeted therapies. IDEAYA is applying its research and drug discovery capabilities to synthetic lethality – which represents an emerging class of precision medicine targets.

IDEAYA's updated corporate presentation is available on its website, at its Investor Relations page: https://ir.ideayabio.com/.

Forward-Looking Statements

This press release contains forward-looking statements, including, but not limited to, statements related to (i) the timing and content of clinical program updates, regulatory updates and clinical trial data readouts; (ii) the potential therapeutic benefits of IDEAYA therapeutics; (iii) the translation of preliminary clinical trial results into future clinical trial results and/or regulatory approval; (iv) timing of development and regulatory milestones; (v) the timing and potential of registration-enabling trial and readouts for darovasertib in 1L HLA-A2 negative MUM; (vi) the timing of the initiation of Phase 3 trial for darovasertib; (vii) the timing and potential for accelerated FDA approval of darovasertib in MUM; (viii) the timing of expansion in IDE397 and Trodelvy combination trial in MTAP-deletion UC and indication in NSCLC; (ix) the timing of combination trial of IDE397 and IDE892 in patients with MTAP-deletion NSCLC; (x) the potential of a Phase 2 expansion monotherapy dose for IDE161; (xi) the timing of initiating IDE161 and DLL3 TOP1i ADC combination trial; (xii) the timing of IDE161 expansion with KEYTRUDA and combinations with TOP1i ADCs in solid tumors; (xiii) timing of INDs for IDE892, IDE034, IDE251, and IDE849; (xiv) timing of data presentation for IDE275 at medical conference; and (xv) the extent to which IDEAYA’s existing cash, cash equivalents, and marketable securities will fund its planned operations. Such forward-looking statements involve substantial risks and uncertainties that could cause IDEAYA's preclinical and clinical development programs, future results, performance or achievements to differ significantly from those expressed or implied by the forward-looking statements. Such risks and uncertainties include, among others, the uncertainties inherent in the drug development process, including IDEAYA's programs' early stage of development, the process of designing and conducting preclinical and clinical trials, the regulatory approval processes, the timing of regulatory filings, the challenges associated with manufacturing drug products, IDEAYA's ability to successfully establish, protect and defend its intellectual property, and other matters that could affect the sufficiency of existing cash to fund operations. IDEAYA undertakes no obligation to update or revise any forward-looking statements. For a further description of the risks and uncertainties that could cause actual results to differ from those expressed in these forward-looking statements, as well as risks relating to the business of IDEAYA in general, see IDEAYA's Annual Report on Form 10-K dated February 20, 2024 and any current and periodic reports filed with the U.S. Securities and Exchange Commission.

Investor and Media Contact

IDEAYA Biosciences Andres Ruiz Briseno SVP, Head of Finance and Investor Relations investor@ideayabio.com (in thousands, except share and per share amounts)

IDEAYA Biosciences, Inc.

Condensed Statements of Operations and Comprehensive Loss

IDEAYA Biosciences, Inc.

Condensed Balance Sheet Data

(in thousands)