Lenzilumab Data Presented in Oral Presentation at the American Society of Hematology (ASH)

  • Lenzilumab (an anti-GM-CSF antibody) in combination with CAR-T cell therapy prevents cytokine release syndrome and neuroinflammation while improving durable control of leukemic disease
  • Exponential increase in T cell proliferation, enhanced anti-tumor activity, and improved overall survival observed with GM-CSF blockade
  • Lenzilumab is a potential next generation strategy to improve the efficacy and safety of CAR-T cellular immunotherapy
  • Company sponsored, multi-center phase I/II clinical trials of lenzilumab in combination with CART19 therapies to be initiated

BURLINGAME, Calif., Dec. 04, 2018 (GLOBE NEWSWIRE) — Humanigen, Inc., (OTCQB: HGEN) (“Humanigen”), a biopharmaceutical company focused on the development of its proprietary Humaneered® monoclonal antibodies to improve the safety and efficacy of chimeric antigen receptor T cell (CAR-T) therapy, announced that final results from the xenograft study of lenzilumab, a first-in-class anti-GM-CSF monoclonal antibody, were presented in the oral plenary session at the 2018 Annual Meeting of the American Society of Hematology, on Monday, December 3rd, 2018 by Rosalie Sterner from Mayo Clinic. The principal investigator for the study was Saad Kenderian, M.B., Ch.B., Mayo Clinic hematologist.   The abstract entitled “GM-CSF Blockade during Chimeric Antigen Receptor T Cell Therapy Reduces Cytokine Release Syndrome and Neurotoxicity and May Enhance Their Effector Functions” was published as a first edition paper by ‘blood’® in the November 21, 2018 edition and is available online at http://www.bloodjournal.org/content/early/2018/11/21/blood-2018-10-881722.  The full abstract with corresponding figures is available for review at: https://ash.confex.com/ash/2018/webprogram/Paper111766.html.

The study was designed to closely replicate the findings in clinical trials and utilized human acute lymphoblastic leukemia (ALL), human CD19 targeted CAR-T (CART19), and human peripheral blood mononuclear cells (PBMCs) and conducted in mice. Within 4-6 days after treatment with CART19, animals began to develop a syndrome characterized by motor weakness, hunched bodies, and progressive weight loss in a model which recapitulates symptoms consistent with cytokine release syndrome (CRS) and neuro-inflammation (NI).

The administration of lenzilumab in combination with CART19 therapy resulted in a significant improvement in leukemic disease control sustained over time for at least 35 days post CART19 administration as compared to CART19 plus isotype control. Dr. Kenderian commented, “We observed an exponential increase in CART19 cell proliferation, enhanced anti-tumor activity, and improved overall survival with GM-CSF blockade. This suggests that GM-CSF neutralization may play a role in reducing relapses and increasing durable complete responses after CART19 cell therapy.”

In addition to improving durable leukemic control, lenzilumab in combination with CART19 therapy, prevented the physical symptoms CRS and resulted in a 75% reduction in NI by quantitative MRI.  Neutralization of GM-CSF with lenzilumab also resulted in a statistically significant reduction in ten other cytokines and chemokines thought to be important in the development of CRS and NI.  These results suggest that GM-CSF is an important regulatory switch that initiates this cascade and plays a central role in the downstream activity of several cytokines and chemokines that are instrumental in the development of CRS and NI. 

Although CART19 therapies are associated with high response rates, 50% of responders are expected to relapse within the first year which is a key consideration in the cost-effectiveness of these therapies. Toxicities of CART19 therapy, including CRS and NI, are also associated with extended hospitalization and ICU admissions, creating an added pharmaco-economic burden that may lead to unfavorable reimbursement, which limits the utility of CAR-T cell therapy. 

Company sponsored, multi-center phase I/II clinical trials of lenzilumab in combination with CART19 therapies are expected to be initiated in the coming months.

In Related News…

The company also announced that Humanigen Chairman and Chief Executive Officer, Cameron Durrant, MD, MBA will be presenting at the 11th annual LD Micro Main Event on Wednesday, December 5, 2018 at 4:00 PM PST.

“With yesterday’s presentation of our lenzilumab study at ASH and the publication of the full study manuscript in the November 21, 2018 first edition of ‘blood®’ as well as our abstract being a recipient of an ASH ‘Outstanding Abstract Achievement Award’, we are delighted to be returning to the LD Micro Main Event Conference to present our investor update,” commented Dr. Durrant. “Lenzilumab’s potential to optimize CAR-T cancer treatment is an exciting proposition for patients, physicians, payers and investors and we are eager to share our study data which demonstrates improved durable leukemic control in addition to prevention of cytokine release syndrome and neuro-inflammation associated with CAR-T, as well as updating attendees on key corporate information,” concluded Durrant.

The LD Micro Main Event will take place December 4th, 5th, and 6th, in Los Angeles at the Luxe Sunset Bel Air Hotel, will feature 250 companies, and will be attended by over 1,200 individuals.

About Humanigen, Inc. 

Humanigen, Inc. is developing its portfolio of Humaneered® monoclonal antibodies to address cutting-edge CAR-T optimization and oncology treatments advancing safer, better, and more effective cancer therapies.  Derived from the company’s Humaneered® platform, lenzilumab and ifabotuzumab are monoclonal antibodies with first-in-class mechanisms. Lenzilumab, which neutralizes circulating GM-CSF, is in development as a potential biologic to make CAR-T therapy safer and more effective, as well as a potential treatment for rare hematologic cancers such as CMML and JMML. Ifabotuzumab, which targets the Eph type-A receptor 3 (EphA3), is being explored as a potential treatment for glioblastoma multiforme (GBM) and other deadly cancers, as a monoclonal antibody, as part of an antibody-drug conjugate, as a backbone for a novel CAR-T construct and a bispecific antibody platform.  For more information, visit www.humanigen.com

About LD Micro
LD Micro was founded in 2006 with the sole purpose of being an independent resource in the microcap space. What started out as a newsletter highlighting unique companies has transformed into several influential events annually (Invitational, Summit, and Main Event).

In 2015, LDM launched the first pure microcap index (the LDMi) to exclusively provide intraday information on the entire sector. LD will continue to provide valuable tools for the benefit of everyone in the small and micro-cap universe. For those interested in attending, please contact David Scher at david@ldmicro.com or visit www.ldmicro.com for more information.

Forward-Looking Statements

This release contains forward-looking statements that are intended to be subject to protection afforded by the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. 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 therapy reach its full potential, including in respect of the anticipated nature and timing of our contemplated Phase I/II clinical trials. 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.

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Al Palombo