RCUS

EX-99.1

2 a2026q18kexhibit991.htm

EX-99.1

Document

Exhibit 99.1

Arcus Biosciences Reports First-Quarter 2026 Financial Results and Provides a Pipeline Update

May 5, 2026

•Arcus outlines development strategy to establish casdatifan as a backbone therapy across each line of treatment for clear cell renal cell carcinoma (ccRCC), including the potential to become the first HIF-2a inhibitor-based tyrosine kinase inhibitor (TKI)-free regimen in the first-line (1L) setting

•Phase 3 PEAK-1 study is enrolling in immunotherapy (IO)-experienced patients with ccRCC, with enrollment completion and the initiation of a 1L Phase 3 study, both expected by year-end 2026

•Arcus selected its first inflammation program clinical candidate AB102, an MRGPRX2 antagonist, which is expected to enter the clinic in the third quarter of 2026; its preclinical profile will be presented in an oral presentation at the Society for Investigative Dermatology Annual Meeting in May

•With $876 million in cash, cash equivalents and marketable securities at quarter-end, Arcus is well positioned to advance casdatifan aggressively, with cash runway until at least the second half of 2028

HAYWARD, Calif. – (BUSINESS WIRE) – Arcus Biosciences, Inc. (NYSE:RCUS), a clinical-stage, global biopharmaceutical company focused on developing differentiated molecules and combination therapies for people with cancer and inflammatory and autoimmune diseases, today reported financial results for the first quarter ended March 31, 2026 and provided a pipeline update on its clinical-stage investigational molecules and discovery programs.

"Arcus is entering a new era, with a clear path for casdatifan to be both first and best in the first-line setting, and a portfolio of wholly owned molecules for inflammation and immunology that provide a new strategic optionality as they move into and through development," said Terry Rosen, Ph.D., chief executive officer of Arcus. "Our highest priority is to establish casdatifan as a foundational standard of care in kidney cancer so that patients have the opportunity to benefit from casdatifan-based regimens across lines of treatment.”

Arcus is focused on completing enrollment for PEAK-1 and initiating a Phase 3 study in the 1L setting, where casdatifan has the potential to become the first HIF-2a inhibitor-based, TKI-free option, by year-end 2026.

Casdatifan (HIF-2a inhibitor)

Casdatifan Development Program:

Arcus’s development strategy is designed to generate evidence to secure casdatifan as a backbone therapy in ccRCC so that every patient has the opportunity to benefit from casdatifan across each line of therapy over the course of their care. The company is aggressively executing on a holistic strategy to embed casdatifan into the treatment paradigm, including in combination with the most commonly used regimen in the 1L setting, anti-PD-1 plus anti-CTLA-4. Arcus is now enrolling a cohort in the Phase 1/1b ARC-20 study to generate the dataset that will support the initiation of the corresponding Phase 3 study at year-end 2026. Arcus’s choice of combination partners has been designed to complement this casdatifan-IO regimen, which has the opportunity to be the first and only such HIF-2a inhibitor-based TKI-sparing 1L therapy, with consecutive treatments with casdatifan-containing regimens in first-, second-, and third-line-plus settings. In this context, Arcus will also begin to evaluate casdatifan plus TKI-containing regimens in 1L and late-line settings, the latter in both HIF-2a inhibitor-experienced and HIF-2a inhibitor-naive patients.

•IO-experienced ccRCC: Enrollment in PEAK-1, the global Phase 3 study evaluating casdatifan plus cabozantinib versus cabozantinib in IO-experienced metastatic ccRCC, is accelerating, and Arcus is on track to complete enrollment by year-end 2026.

•1L ccRCC: Arcus has been focused on the evaluation of casdatifan-based TKI-free regimens, which have demonstrated a consistently low rate of primary progression across all cohorts and settings evaluated to date.

▪Most notably, casdatifan plus zimberelimab (anti-PD-1) showed a primary progression rate of 7% (2 of 30 patients), comparing quite favorably to published rates observed with anti-PD-1 monotherapy or ipilimumab (anti-CTLA-4) plus nivolumab (anti-PD-1) in the 1L setting. This ARC-20 cohort is fully enrolled.

▪A cohort evaluating casdatifan plus zimberelimab and ipilimumab in ARC-20 is currently enrolling with the purpose of supporting Arcus’s first Phase 3 study in the 1L setting.

Planned Data Readouts:

Arcus expects to have multiple data readouts for casdatifan in 2026:

•More mature overall response rate data and initial progression-free survival data for approximately 45 patients treated in the ARC-20 cohort evaluating casdatifan plus cabozantinib in the IO-experienced setting will be presented at an investor event or at a medical conference. All patients will have had at least 12 months of follow-up.

•Initial data from the

rcus-20260225false000172452100017245212026-02-252026-02-25

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 25, 2026

Arcus Biosciences, Inc. (Exact name of Registrant as Specified in Its Charter)

Delaware001-3841947-3898435 (State or Other Jurisdiction of Incorporation) (Commission File Number)(IRS Employer Identification No.)

3928 Point Eden Way Hayward, California 94545 (Address of Principal Executive Offices)(Zip Code)

Registrant’s Telephone Number, Including Area Code: (510) 694-6200 (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

oWritten communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

oSoliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

oPre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

oPre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered

Common Stock, Par Value $0.0001 Per ShareRCUSThe New York Stock Exchange

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter). Emerging growth company o If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

Item 2.02 Results of Operations and Financial Condition. On February 25, 2026, Arcus Biosciences, Inc. issued a press release announcing its financial results for the three months and full year ended December 31, 2025. The full text of the press release is furnished as Exhibit 99.1 hereto and is incorporated herein by reference. The information in this Item 2.02 of this Form 8-K (including Exhibit 99.1) is intended to be furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended or the Exchange Act, except as expressly set forth by specific reference in such filing.

Item 9.01 Financial Statements and Exhibits. (d)Exhibits.

Exhibit No.Description 99.1Press release dated February 25, 2026

104Cover Page Interactive Data File (embedded within the Inline XBRL Document)

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

ARCUS BIOSCIENCES, INC.

Date: February 25, 2026 By:/s/ Terry Rosen, Ph. D. Terry Rosen, Ph.D. Chief Executive Officer

rcus-20251028false000172452100017245212025-10-282025-10-28

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 28, 2025

Arcus Biosciences, Inc. (Exact name of Registrant as Specified in Its Charter)

Delaware001-3841947-3898435 (State or Other Jurisdiction of Incorporation) (Commission File Number)(IRS Employer Identification No.)

3928 Point Eden Way Hayward, California 94545 (Address of Principal Executive Offices)(Zip Code)

Registrant’s Telephone Number, Including Area Code: (510) 694-6200 (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

oWritten communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

oSoliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

oPre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

oPre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered

Common Stock, Par Value $0.0001 Per ShareRCUSThe New York Stock Exchange

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter). Emerging growth company o If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

Item 2.02 Results of Operations and Financial Condition. On October 28, 2025, Arcus Biosciences, Inc. issued a press release announcing its financial results for the nine months ended September 30, 2025. The full text of the press release is furnished as Exhibit 99.1 hereto and is incorporated herein by reference. The information in this Item 2.02 of this Form 8-K (including Exhibit 99.1) is intended to be furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended or the Exchange Act, except as expressly set forth by specific reference in such filing.

Item 9.01 Financial Statements and Exhibits. (d)Exhibits.

Exhibit No.Description 99.1Press release dated October 28, 2025

104Cover Page Interactive Data File (embedded within the Inline XBRL Document)

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

ARCUS BIOSCIENCES, INC.

Date: October 28, 2025 By:/s/ Terry Rosen, Ph. D. Terry Rosen, Ph.D. Chief Executive Officer (Principal Executive Officer)