generated to date show that intravenous administration of EIK1001 has been generally well-tolerated, activates readily measured systemic immune responses, and can be combined with current standard-of-care for the treatment of malignant disease.

A more complete characterization of these durable responses will be presented at the ESMO Congress 2026 in October.

EIK1003 & EIK1004

EIK1003 and EIK1004 are highly selective PARP1 inhibitors designed to inhibit PARP1 while sparing PARP2, thereby promoting tumor regression by targeting the DNA damage response of cancer cells. EIK1004 was specifically engineered to penetrate the central nervous system (CNS), potentially expanding the utility of selective PARP1 inhibition to tumors involving the brain and CNS. Eikon believes the selectivity of EIK1003 and EIK1004 may enable the development of near full-dose combination regimens with chemotherapy, antibody-drug conjugates, or radionuclides, in earlier lines of therapy than currently possible with non-selective PARP inhibitors, and will potentially allow for more sustained therapeutic dosing during maintenance treatment.

EIK1005

EIK1005 is a novel molecular entity, designed to inhibit the Werner (“WRN”) helicase, that emerged from original research conducted in Eikon’s laboratories. Eikon believes that EIK1005 has the potential to be an effective anti-tumor agent for microsatellite instability-high (MSI-high) tumors, by producing synthetic lethality in MSI-high cells that depend upon the WRN helicase salvage pathway to maintain genome integrity.

EIK1006

EIK1006 is another internally-derived clinical candidate and is being investigated as a potential next-generation androgen receptor (“AR”) antagonist with activity against multiple clinically important genetic variants of AR that emerge during treatment with conventional AR blockers. Preclinically, Eikon scientists have shown that EIK1006 binds to the ligand binding domain of AR and blocks its nuclear translocation, thereby inhibiting AR transcriptional activity and downstream signaling.

Key Upcoming Milestones

Second Quarter 2026 Corporate Highlights

Appointment of Ma. Fatima D. Francisco to Board of Directors

Eikon appointed Ma. Fatima (“Fama”) D. Francisco as an independent director to its Board of Directors, where Ms. Francisco will also serve on the Board’s Compensation Committee.

Ms. Francisco most recently served as Chief Executive Officer, Baby, Feminine and Family Care at The Procter & Gamble Company, where she led one of the company's largest global business units. During her more than 35-year career at Procter & Gamble, she has held numerous leadership positions across marketing, innovation, commercial operations, and general management. She also serves on the Board of Directors of HP Inc. and Nestlé S.A., and previously served on the Board of Directors of Organon & Co.

Second Quarter 2026 Financial Results

Cash Position: As of June 30, 2026, Eikon had cash, cash equivalents, and marketable securities of $531.2 million. Eikon expects its current cash, cash equivalents, and marketable securities to fund operations into the second half of 2027.

Research and Development (“R&D”) Expenses: R&D expenses were $75.5 million for the three months ended June 30, 2026, compared to $69.2 million for the three months ended June 30, 2025, an increase of $6.3 million, or 9%. Direct research and development expenses increased by $12.8 million as we advanced our clinical trial activity, and compensation costs increased by $1.7 million. These increases were partially offset by restructuring expenses and milestone payments in the prior year period and by lower occupancy costs.

General and Administrative (“G&A”) Expenses: G&A expenses were $17.9 million for the three months ended June 30, 2026, compared to $40.5 million for the three months ended June 30, 2025, a decrease of $22.5 million, or 56%. The decrease was primarily due to the impairment in the year-ago period of $10.7 million of property and equipment and $10.3 million of operating lease right-of-use assets relating to properties in Hayward, California that Eikon vacated in April 2025 when the Company moved into its current corporate headquarters in Millbrae, California.

Net Loss: Net loss attributable to common stockholders was $88.4 million for the second quarter of 2026, compared to $105.2 million for the prior-year period.

“Our strong balance sheet enables us to continue to support an increasingly mature pipeline, including ongoing registrational studies of EIK1001 in both advanced melanoma and non-small cell lung cancer,” said Freddie Bowie, Ph.D., Chief Financial

Officer. “Additional development programs to be reviewed at ESMO demonstrate our ability to execute global clinical trials across multiple indications. We remain focused on deploying capital toward opportunities that we believe have the potential to significantly enhance shareholder value over the next few years.”

About Eikon Therapeutics

Eikon is a late-stage clinical biopharmaceutical company dedicated to building a global, fully integrated organization developing innovative medicines to address serious unmet medical needs. Eikon’s initial focus is oncology, where it is advancing a pipeline of drug candidates that could eventually become lifesaving medicines. Eikon deploys its technology platform, including its proprietary single molecule tracking system, to develop internally derived novel therapies, while also leveraging the deep expertise of its management team to in-license promising assets. Eikon’s vision is to become a generational leader, by purposefully integrating traditional biology research with advanced engineering to develop better medicines faster. For more information, visit www.eikontx.com.

Forward-Looking/Safe Harbor Statements

This press release contains forward-looking statements within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. All statements in this press release that are not historical facts are hereby identified as forward-looking statements for this purpose. These statements may be identified by words such as “aims,” “anticipates,” “believes,” “could,” “estimates,” “expects,” “forecasts,” “goal,” “intends,” “may,” “plans,” “possible,” “potential,” “seeks,” “will” and variations of these words or similar expressions that are intended to identify forward-looking statements, although not all forward-looking statements contain these words. Forward-looking statements in this press release include, but are not limited to, statements regarding: the therapeutic potential of Eikon’s product candidates; the timing for anticipated data readouts; expected milestones and business objectives for 2026 and beyond, including Eikon’s anticipated presentations at the ESMO Congress 2026 and the anticipated cash runway into the second half of 2027; and other statements regarding Eikon’s future operations, financial performance, financial position, prospects, objectives, strategies and other future events.

These forward-looking statements are based upon management’s current expectations and assumptions, and are subject to a number of risks, uncertainties and other factors that could cause actual results and events to differ materially and adversely from those indicated by such forward-looking statements including, among others: Eikon’s limited operating history; its significant net losses incurred since inception and the likelihood of incurring additional losses for the foreseeable future; its need for substantial additional funding; the early stage of development of many of its product candidates and the possibility that its product candidates may fail in development; its dependence on the success of its current product candidates; its ability to leverage its technology platform to enable more informed drug research and development; legal and regulatory risks; intellectual property-related risks; and those risks, uncertainties and other factors discussed under the caption “Risk Factors” and elsewhere in Eikon’s Quarterly Report

on Form 10-Q for the quarter ended June 30, 2026, filed with the Securities and Exchange Commission (“SEC”) on August 13, 2026, and in other public filings with the SEC in the future.

As a result, you should not place undue reliance on any forward-looking statements. The forward-looking statements made in this press release speak only as of the date of this press release, and Eikon undertakes no obligation to update such forward-looking statements, whether as a result of new information, future developments or otherwise, except as required by law.

Contacts:

Investors

Alfred “Freddie” Bowie, Ph.D., CFO

ir@eikontx.com

Media

Colin Sanford

colin@bioscribe.com

Eikon Therapeutics, Inc.

Statements of Operations and Comprehensive Loss

(in thousands, except share and per share amounts)

(Unaudited)

Eikon Therapeutics, Inc.

Condensed Balance Sheet Data

(in thousands)

(Unaudited)