Novel Bispecific Antibody Targeting Biological Pathway Implicated in Multiple Solid Tumor Indications

SEATTLE, WA, USA and LUND, Sweden I August 17, 2017 I Aptevo Therapeutics Inc. (Nasdaq:APVO), a biotechnology company focused on developing novel immuno-oncology and hematology therapeutics, and Alligator Bioscience (Nasdaq Stockholm:ATORX), a biotechnology company developing antibody-based pharmaceuticals for tumor-directed immunotherapy, announced today that the companies have initiated CMC activities for the manufacturing of clinical material in preparation for a future investigational new drug (IND) submission for the bispecific immuno-oncology antibody ALG.APV-527.

ALG.APV-527 was the subject of a collaboration agreement announced by the companies in July 2017. It targets the co-stimulatory receptor 4-1BB and an undisclosed tumor antigen that directs the immune activation to the tumor area. 4-1BB is known to enhance the immune response to cancer through activation of tumor-specific T cells and is believed to be a promising target for new immunotherapeutic approaches. The bispecific antibody candidate could potentially have utility in the treatment of a broad spectrum of cancers over-expressing the tumor antigen, including breast, cervical, non-small-cell-lung, prostate, renal, gastric, colorectal and bladder cancers.

“With CMC and IND enabling activities underway, our partnership with Aptevo is moving ahead rapidly,” said Per Norlén, Chief Executive Officer of Alligator Bioscience. “Having worked collaboratively to design and engineer ALG.APV-527, we are pleased to now announce its advancement into preclinical development. This bispecific antibody brings tumor directed immunotherapy to the next level. By making the immune activation dependent on binding to a tumor antigen we have created a candidate drug with potential for improved efficacy and fewer side effects.”

“The timely progress we are making underscores our respective companies’ expertise in bispecific antibody engineering and we are very excited to begin the next phase of development of ALG.APV-527 and further demonstrate the elegance of our ADAPTIR technology platform,” said Marvin L. White, President and Chief Executive Officer of Aptevo.  “The robust and flexible nature of our ADAPTIR platform permits the development of bispecific antibodies with different mechanisms of immune system engagement.  Because ADAPTIR bispecifics are based on an IgG backbone, they have excellent stability and manufacturing characteristics, with traditional monoclonal antibody-like manufacturing properties – a key differentiator from other bispecific constructs.  As an emerging class of new therapeutics, bispecific antibodies may offer important technological advancements over traditional monoclonal antibodies, including the potential for more precise targeted therapy through enhanced functionality, potency and efficacy.  We look forward to advancing ALG.APV-527 towards IND submission and to further validating the utility of our ADAPTIR protein therapeutic platform.”

About Aptevo Therapeutics Inc.

Aptevo Therapeutics Inc. is a clinical-stage biotechnology company focused on novel oncology and hematology therapeutics to meaningfully improve patients’ lives.  The Company has four commercial products – IXINITY®, WinRho® SDF, HepaGam B® and VARIZIG® and a versatile core technology – the ADAPTIR™ modular protein technology platform capable of generating highly-differentiated, bispecific antibodies with unique mechanisms of action.  Aptevo’s primary focus is immuno-oncology, with two ADAPTIR candidates currently in clinical development and a broad portfolio of bispecific immunotherapies in preclinical development.  For more information, please visit

About Alligator Bioscience

Alligator Bioscience is a clinical-stage biotechnology company developing tumor-directed immuno-oncology antibody drugs. Alligator’s growing pipeline includes lead clinical and pre-clinical product candidates (ADC-1013, ATOR-1015, ATOR-1017, and ALG.APV-527) and novel research candidates. ADC-1013 is licensed to Janssen Biotech, Inc., part of J&J, for development and commercialization. Alligator’s shares are listed on Nasdaq Stockholm (ATORX). The Company is headquartered in Lund, Sweden, and has approximately 45 employees. For more information, please visit

SOURCE: Aptevo Therapeutics