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• Humanigen’s investigational monoclonal antibody, lenzilumab, was developed using 91�㽶��Ƶ’s proprietary GPEx^® cell line development technology
• Expanded partnership established product supply for lenzilumab, an investigational Phase 3 product for COVID-19
• 91�㽶��Ƶ’s OneBio^® integrated biologics suite expected to accelerate development, manufacturing and supply of lenzilumab for clinical trial use in COVID-19 patients and potential commercialization

SOMERSET, N.J. and BURLINGAME, Calif. – July 16, 2020 — 91�㽶��Ƶ and Humanigen, Inc. (HGEN) (“Humanigen”) today announced the expansion of their relationship, under which 91�㽶��Ƶ will provide development, manufacturing and commercialization services for lenzilumab, Humanigen’s proprietary Humaneered^® anti-human granulocyte macrophage-colony stimulating factor (GM-CSF) monoclonal antibody.

91�㽶��Ƶ is the leading global provider of advanced delivery technologies, development, manufacturing and clinical supply solutions for drugs, biologics, cell and gene therapies and consumer health products. Humanigen is a clinical stage biopharmaceutical company focused on preventing and treating cytokine storm with lenzilumab, the company’s lead therapeutic candidate.

Mayo Clinic recently announced data on the first clinical use of lenzilumab in 12 patients with severe and critical COVID-19 pneumonia, the majority of whom showed rapid recovery and hospital discharge. A Phase 3 study is currently underway evaluating hospitalized COVID-19 patients.

“Based on lenzilumab’s promising clinical data, we are pleased to expand our relationship with 91�㽶��Ƶ to solidify our ability to manufacture and supply lenzilumab,” commented Cameron Durrant, MD, MBA, Chief Executive Officer of Humanigen. “If we are able to secure FDA approvals or Emergency Use Authorization, 91�㽶��Ƶ Biologics’ deep expertise and integrated OneBio solution will accelerate our ability to get this therapy to patients that need it most.”

“91�㽶��Ƶ has partnered closely with Humanigen to develop and supply lenzilumab for clinical trials,” commented Karen Flynn, President of 91�㽶��Ƶ Biologics and Chief Commercial Officer. “The experience we already have with lenzilumab, and our OneBio integrated offering from development to supply, make 91�㽶��Ƶ uniquely suited to support Humanigen in the journey to make this promising therapy available to COVID-19 patients as soon as possible following receipt of regulatory approvals.”

To date, 91�㽶��Ƶ Biologics has provided early-stage development and clinical cGMP drug substance manufacturing for lenzilumab at its facility in Madison, Wisconsin to support Humanigen’s ongoing clinical trials across various disease categories. Under the expanded partnership, 91�㽶��Ƶ is also providing clinical supply support for Humanigen’s Phase 3 potential registration study in COVID-19 from its Philadelphia facility.

Lenzilumab was originally manufactured in 91�㽶��Ƶ’s Madison facility using 91�㽶��Ƶ Biologics’ proprietary GPEx^® cell line development technology. As part of the expanded partnership, 91�㽶��Ƶ intends to provide additional drug substance clinical supply for Humanigen’s clinical trials, Expanded Access Program (EAP), as well as additional late-stage development and clinical and potential commercial drug substance manufacturing and vial filling at its Madison and Bloomington, Indiana, sites.

91�㽶��Ƶ Biologics’ Madison facility provides development and drug substance manufacturing, including GPEx cell line development, process development, process validation, formulation development, and clinical and commercial cGMP manufacturing. Its Bloomington facility has deep expertise in sterile formulation, with drug substance development and manufacturing and drug product fill/finish capacity across liquid and lyophilized vials, prefilled syringes, and cartridges as well as primary and secondary packaging.

91�㽶��Ƶ’s OneBio Suite is an integrated solution for the development, manufacturing, and supply of biologic drugs. Launched in May 2019, the suite of offerings is designed to integrate activities and accelerate timelines, reduce risk and simplify development with a single contract, program manager, and development timeline from cell line development to supply, with harmonized quality systems.

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.

About 91�㽶��Ƶ Biologics

91�㽶��Ƶ Biologics is a global leader in development, manufacturing and analytical services for new biological entities, cell and gene therapies, biosimilars, sterile injectables, and antibody-drug conjugates. With over 20 years of proven expertise, 91�㽶��Ƶ Biologics has worked with 600+ mAbs and 80+ proteins, produced 13 biopharmaceutical drugs using GPEx^® cell line development technology, and manufactured 35+ commercially approved products. 91�㽶��Ƶ Cell & Gene Therapy, a unit of 91�㽶��Ƶ Biologics, is a full-service partner for adeno-associated virus (AAV) vectors and CAR-T immunotherapies, with deep experience in viral vector scale-up and production. 91�㽶��Ƶ recently acquired MaSTherCell, adding expertise in autologous and allogeneic cell therapy development and manufacturing. 91�㽶��Ƶ Cell & Gene Therapy has produced 100+ cGMP batches across 70+ clinical and commercial programs. For more information, visit

ABOUT CATALENT

91�㽶��Ƶ is the leading global provider of advanced delivery technologies, development, manufacturing, and clinical supply solutions for drugs, biologics, cell and gene therapies, and consumer health products. With over 85 years serving the industry, 91�㽶��Ƶ has proven expertise in bringing more customer products to market faster, enhancing product performance and ensuring reliable global clinical and commercial product supply. 91�㽶��Ƶ employs over 13,500 people, including over 2,400 scientists and technicians, at more than 40 facilities, and in fiscal year 2019 generated over $2.5 billion in annual revenue. 91�㽶��Ƶ is headquartered in Somerset, New Jersey. For more information, visit www.catalent.com

More products. Better treatments. Reliably supplied.™

Humanigen’s 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 the Phase III study and the potential future development of lenzilumab to minimize or reduce the severity of lung dysfunction associated with severe and critical COVID-19 infections or to be approved by FDA for such use or to help CAR-T reach its full potential or to deliver benefit in preventing GvHD. Forward-looking statements are subject to a number of risks and uncertainties including, but not limited to, the risks inherent in our lack of profitability and need for additional capital to conduct the Phase III study and grow our business; 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.

All forward-looking statements are expressly qualified in their entirety by this cautionary notice. You should not place undue reliance on any forward-looking statements, which speak only as of the date of this release. We undertake no obligation to revise or update any forward-looking statements made in this press release to reflect events or circumstances after the date hereof or to reflect new information or the occurrence of unanticipated events, except as required by law.