Humanigen Announces Two Abstracts Accepted at the 2019 Annual Meeting of the Society for Neuro-Oncology, including Oral Presentation on its Next Generation EphA3-CAR-T

November 12, 2019

  • EphA3 is a novel CAR-T tumor target expressed in tumor neovasculature and stroma

  • Phase I study of ifabotuzumab (anti-EphA3 antibody) resulted in rapid, specific and reproducible targeting of the tumor microenvironment (TME) and tumor vasculature in patients with glioblastoma multiforme (GBM)

  • EphA3-CAR-T, built on the ifabotuzumab backbone, demonstrated specific and potent anti-tumor activity against patient GBM cell lines

Burlingame, CA, November 12, 2019 – Humanigen, Inc., (HGEN) (“Humanigen”), a clinical stage biopharmaceutical company focused on the development of next generation chimeric antigen receptor T cell (CAR-T) and other cell therapies, today announced that two abstracts supporting development of its next generation EphA3-CAR-T program, built on the backbone of ifabotuzumab, the company’s proprietary Humaneered® anti-EphA3 monoclonal antibody, have been accepted for presentation at the 2019 annual meeting of the Society for Neuro-Oncology (SNO) being held November 20-24, 2019 in Phoenix, AZ.

While CAR-T therapy has revolutionized the treatment landscape for hematological malignancies, its efficacy remains limited in solid tumors. The majority of CAR-T therapies targeting solid tumors have focused on cell surface receptors expressed on tumor cells.  However, given the heterogeneity of surface receptor expression on solid tumors and the difficulty of navigating the immunosuppressive stromal microenvironment, strategies to target tumor neovasculature and tumor stromal cells are emerging. Targeting non-transformed, tumor neovasculature and tumor stroma cells may overcome antigen loss and may modulate the suppressive TME.  EphA3, an oncofetal antigen, is selectively expressed in tumor neovasculature and tumor stromal cells in brain cancers and other solid tumors making it a novel target for CAR-T development.

 

The phase I clinical study, led by Prof. Hui Gan and Prof. Andrew Scott from the Olivia Newton-John Cancer Research Institute in Melbourne, Australia, was funded by the Cure Brain Cancer Foundation. The study used radiolabeled ifabotuzumab followed by sequential positron emission tomography (PET) imaging to determine biodistribution, frequency of in situ EphA3 expression and quantitative tumor uptake of ifabotuzumab.  The preliminary results include data from eight patients who have been enrolled to date.  PET/computed tomography (CT) imaging showed that ifabotuzumab is effectively delivered across the blood-tumor barrier and accumulates specifically at the tumor site in all patients treated to date with no observed normal tissue uptake.  Magnetic resonance imaging (MRI) scans showed predominant T2/FLAIR changes, consistent with the treatment effect of ifabotuzumab on tumor vasculature. Treatment emergent adverse events were readily managed with increased premedications after the first occurrence. The abstract is available online at: https://academic.oup.com/neuro-oncology/article-abstract/21/Supplement_6/vi6/5619490?redirectedFrom=fulltext

 

Professors Gan and Scott stated “Our results show that ifabotuzumab is safe and very effective at targeting the tumour. We are also excited that there are early indications that ifabotuzumab may help to control disease growth in some patients.”

 

Using a single chain variable region fragment of ifabotuzumab, a second generation CD28 co-stimulated CAR construct was developed.  Using primary patient derived GBM cell lines, the EphA3 CAR-T demonstrated specific and potent anti-tumor activity.  Data from in vivo and combinatorial CAR-T experiments will be reported during the oral presentation scheduled on Friday, November 22, 2019 at 4:40pm. The abstract is available online at: https://academic.oup.com/neuro-oncology/article-abstract/21/Supplement_6/vi88/5619352?redirectedFrom=fulltext

 

“These results indicate for the first time that targeting EphA3 with CAR-T cells is feasible, efficacious, and represents a novel therapeutic strategy for solid tumors” stated Dr. Cameron Durrant, CEO of Humanigen.  “Our EphA3-CAR-T program as another pillar in our developing cell therapy pipeline.  While we continue to develop our GM-CSF neutralization platform with Kite, we are also busy building next generation CAR-T therapies with our combinatorial GM-CSF gene-editing platform and our other CAR-T programs focused on novel tumor targets”, Dr. Durrant continued.  

About Humanigen, Inc. 

 

Humanigen, Inc. is developing its portfolio of next-generation cell and gene therapies for the treatment of cancers via its novel, cutting-edge GM-CSF neutralization and gene-knockout platforms.  There is a direct correlation between the efficacy of CAR-T therapy and the incidence of life-threatening toxicities (referred to as the efficacy/toxicity linkage).  We believe that our GM-CSF neutralization and gene-editing platform technologies have the potential to reduce the inflammatory cascade associated with serious and potentially life-threatening CAR-T therapy-related side effects while preserving and potentially improving the efficacy of the CAR-T therapy itself, thereby breaking the efficacy/toxicity linkage.  The company’s immediate focus is combining FDA-approved and development stage CAR-T therapies with lenzilumab, the company’s proprietary Humaneered® anti-human-GM-CSF immunotherapy, which is its lead product candidate.  A clinical collaboration with Kite, a Gilead Company, was recently announced to evaluate the sequential use of lenzilumab with Yescarta®, axicabtagene ciloleucel, in a multicenter clinical trial in adults with relapsed or refractory large B-cell lymphoma.  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).  The company has established several partnerships with leading institutions to advance its innovative cell and gene therapy pipeline.  For more information, visit www.humanigen.com

About the Olivia Newton-John Cancer Research Institute

 

The Olivia Newton-John Cancer Research Institute is a leader in the development of experimental and breakthrough cancer treatments. We investigate and develop treatments for cancers of the breast, lung, skin, prostate, liver, gastrointestinal tract and brain. Our researchers and clinicians are running more than 120 clinical trials, giving patients access to potential new treatments including immunotherapies and personalized medicine. 

 

Located in Heidelberg, Victoria, Australia, the Institute is integrated within the ONJ Centre, with research laboratories only metres away from where patients are cared for and receive treatment. This inspires and enables the rapid translation of scientific discovery into clinical trial of new, better, cancer treatments.

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 future development of lenzilumab 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 Black Horse Capital and its affiliates owning more than 50% of our outstanding common stock, including their ability to control the company; our lack of profitability and need for additional capital to operate our business as a going concern; 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.

CONTACT:​

Investors:

Al Palombo – 650-243-3181

ir@humanigen.com

Media:

Chris Bowe – 646-662-7628

cbowe@humanigen.com

Source: Humanigen, Inc.

Released November 12, 2019

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