Gilead Sciences and Arcus Biosciences Complete Closing of Their 10-Year Partnership to Co-Develop and Co-Commercialize Next-Generation Cancer Immunotherapies

Gilead Sciences, Inc. (Nasdaq: GILD) and Arcus Biosciences, Inc. (NYSE: RCUS), an oncology-focused biopharmaceutical company working to create best-in-class cancer therapeutics, announced today the closing of their option and co-development and co-commercialization partnership agreement signed on May 27, 2020.

The closing occurred following the expiration of the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976.

Under the terms of the agreements, the closing of this transaction triggered a payment of $175 million by Gilead to Arcus. In addition, Gilead made an equity investment in Arcus of approximately $200 million by purchasing shares at a price of $33.54 per share. As a result of this investment and Gilead's participation in Arcus's follow-on offering on May 28, 2020, Gilead now owns nearly 8.2 million shares of common stock of Arcus, representing approximately 13 percent of Arcus's outstanding shares.

About Arcus Biosciences

Arcus Biosciences is an oncology-focused biopharmaceutical company leveraging its deep cross-disciplinary expertise to discover highly differentiated therapies and to develop a broad portfolio of novel combinations addressing significant unmet needs. Arcus currently has four molecules in clinical development. AB928, the first and only dual A_2a/A_2b adenosine receptor antagonist in the clinic, is being evaluated in multiple Phase 1b/2 studies across different indications, including prostate, colorectal, non-small cell lung, pancreatic, triple-negative breast and renal cell cancers. AB680, the first small-molecule CD73 inhibitor in the clinic, is in Phase 1 development for first-line treatment of metastatic pancreatic cancer in combination with zimberelimab and gemcitabine/nab-paclitaxel. AB154, an anti-TIGIT monoclonal antibody and new potential immuno-oncology backbone therapy, is in a three-arm randomized Phase 2 study for first-line treatment of PD-L1-high metastatic non-small cell lung cancer evaluating zimberelimab monotherapy, AB154 with zimberelimab and AB154 plus AB928 with zimberelimab. Zimberelimab (AB122), Arcus's anti-PD-1 monoclonal antibody, is also being evaluated in a Phase 1b study as monotherapy for cancers with no approved anti-PD-1 treatment options, and in various combinations across the portfolio. For more information about Arcus Biosciences, please visit www.arcusbio.com.

About Gilead Sciences

Gilead Sciences, Inc. is a research-based biopharmaceutical company that discovers, develops and commercializes innovative medicines in areas of unmet medical need. The company strives to transform and simplify care for people with life-threatening illnesses around the world. Gilead has operations in more than 35 countries worldwide, with headquarters in Foster City, California. For more information on Gilead Sciences, please visit the company's website at www.gilead.com.

Gilead Forward-Looking Statements

This press release includes forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 that are subject to risks, uncertainties and other factors, including the ability of the parties to meet potential milestones in the estimated timelines or at all and the risk that the parties may not realize the expected benefits of this collaboration. All statements other than statements of historical fact are statements that could be deemed forward-looking statements. These risks, uncertainties and other factors could cause actual results to differ materially from those referred to in the forward-looking statements. The reader is cautioned not to rely on these forward-looking statements. These and other risks are described in detail in Gilead's Quarterly Report on Form 10-Q for the quarter ended March 31, 2020, as filed with the U.S. Securities and Exchange Commission. All forward-looking statements are based on information currently available to Gilead, and Gilead assumes no obligation to update any such forward-looking statements.