First Patient Infused in Joint Humanigen/Kite, A Gilead Company Clinical Study

• ZUMA-19 study being conducted as part of a clinical collaboration in the U.S.
• Study evaluating the potential effects of lenzilumab (anti-human-GM-CSF monoclonal antibody) prior to Yescarta® (axicabtagene ciloleucel) in adults with relapsed or refractory large B-cell lymphoma

BURLINGAME, Calif.--(BUSINESS WIRE)--Humanigen, Inc., (HGEN) (“Humanigen”), a clinical stage biopharmaceutical company focused on preventing and treating cytokine release syndrome (CRS) with lenzilumab, the company’s proprietary Humaneered^® anti-human granulocyte macrophage-colony stimulating factor (GM-CSF) monoclonal antibody, announced that the first patient has been infused in the ZUMA-19 study, which is being conducted in collaboration with Kite, A Gilead Company. Details of the ZUMA-19 study can be found at www.clinicaltrials.gov/ct2/show/NCT04314843.

“We are excited to see this clinical collaboration move forward as we seek to understand the potential benefit of lenzilumab being administered with CAR T therapy in patients with relapsed or refractory large B-cell lymphoma,” said Cameron Durrant, MD, chief executive officer of Humanigen.

About Humanigen, Inc.

Humanigen, Inc. is developing its portfolio of clinical and pre-clinical therapies for the treatment of cancers and infectious diseases via its novel, cutting-edge GM-CSF neutralization and gene-knockout platforms. We believe that our GM-CSF neutralization and gene-editing platform technologies have the potential to reduce the inflammatory cascade associated with coronavirus infection. The company’s immediate focus is to prevent or minimize the cytokine release syndrome that precedes severe lung dysfunction and ARDS in serious cases of SARS-CoV-2 infection. The company is also focused on creating next-generation combinatory gene-edited CAR-T therapies using strategies to improve efficacy while employing GM-CSF gene knockout technologies to control toxicity. In addition, the company is developing its own portfolio of proprietary first-in-class EphA3-CAR-T for various solid cancers and EMR1-CAR-T for various eosinophilic disorders. The company is also exploring the effectiveness of its GM-CSF neutralization technologies (either through the use of lenzilumab as a neutralizing antibody or through GM-CSF gene knockout) in combination with other CAR-T, bispecific or natural killer (NK) T cell engaging immunotherapy treatments to break the efficacy/toxicity linkage, including to prevent and/or treat graft-versus-host disease (GvHD) in patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT). Additionally, Humanigen and Kite, a Gilead Company, are evaluating lenzilumab in combination with Yescarta® (axicabtagene ciloleucel) in patients with relapsed or refractory large B-cell lymphoma in a clinical collaboration. For more information, visit www.humanigen.com

Forward-Looking Statements

This release contains forward-looking statements. Forward-looking statements reflect management's current knowledge, assumptions, judgment and expectations regarding future performance or events. Although management believes that the expectations reflected in such statements are reasonable, they give no assurance that such expectations will prove to be correct and you should be aware that actual events or results may differ materially from those contained in the forward-looking statements. Words such as "will," "expect," "intend," "plan," "potential," "possible," "goals," "accelerate," "continue," and similar expressions identify forward-looking statements, including, without limitation, statements regarding our expectations for CAR-T to reach its full potential, the Phase III study and the potential future development of lenzilumab in COVID-19 or to be approved by FDA for such use or to deliver benefit in preventing GvHD. Forward-looking statements are subject to a number of risks and uncertainties including, but not limited to our lack of profitability and operate our business as a going concern; our dependence on partners to further the development of our product candidates; the uncertainties inherent in the development and launch of any new pharmaceutical product; the outcome of pending or future litigation; and the various risks and uncertainties described in the "Risk Factors" sections and elsewhere in the Company's periodic and other filings with the Securities and Exchange Commission.

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