skip to page content

Homology Medicines Presents Data Demonstrating Highly Efficient, On-Target In Vivo Gene Editing Capabilities of its Novel Human-Derived Adeno-Associated Virus Vectors

BEDFORD, Mass., May 15, 2017 – Homology Medicines, Inc., a genetic medicines company translating proprietary gene editing and gene therapy technologies into novel treatments for patients, announced today the presentation of preclinical data demonstrating that its nuclease-free gene editing platform can induce highly efficient and on-target gene insertion in vivo through homologous recombination.

Homology’s AMEnDR™ (AAV-Mediated Editing by Direct Homologous Recombination) technology represents a new therapeutic approach to cure genetic diseases. Homology’s scientists also presented preclinical biodistribution data showing that the Company’s novel adeno-associated virus (AAV) vectors can cross the blood brain barrier as well as data showing that the incidence of pre-existing neutralizing antibodies in humans is low compared to most other AAVs.

“Our gene editing data demonstrate that our novel, human-derived AAV vectors can insert genes precisely and efficiently in vivo through the process of homologous recombination without the need for a nuclease,” said Arthur Tzianabos, Ph.D., Chief Executive Officer of Homology Medicines. “Our editing data, along with our vectors’ superior tropism for multiple tissues and the low level of neutralizing antibodies in humans, demonstrate the therapeutic potential of our technology platform to cure genetic diseases.”

In an oral and a poster presentation at the American Society of Gene & Cell Therapy (ASGCT) Annual Meeting May 10-13, 2017, Homology’s scientists presented preclinical gene editing data with its AAV vectors derived from human hematopoietic stem cells (AAVHSCs). The data demonstrated that Homology’s AMEnDR technology is:

  • Driven by homologous recombination, the natural biological mechanism used by cells to ensure highly precise DNA repair. AAVHSC editing was observed in all cells tested except for those deficient in BRCA2, which is an essential mediator of homologous recombination.
  • Precise and on-target. Sanger and next-generation sequencing showed AAVHSCs induce seamless editing, with no evidence of inverted terminal repeats or indel mutations and with off-target reads comparable to background control levels.
  • Efficient at editing in vivo. AAVHSCs demonstrated efficient in vivo editing levels following a single intravenous injection.

In two additional presentations, Homology demonstrated that its AAVHSCs:

  • Cross the blood brain barrier in non-human primates and effectively transduce the central and peripheral nervous systems.
  • Exhibit low levels of pre-existing neutralizing antibodies based on a sample of 100 human sera.

To view the abstracts, visit

About Homology Medicines, Inc.
Homology Medicines is a genetic medicines company translating proprietary gene editing and gene therapy technologies into novel treatments for patients with rare diseases. The combination of a new multidimensional technology platform and a management team that has successfully developed and commercialized rare disease therapies uniquely positions the Company to move beyond the current limitations of gene therapy and gene editing approaches to improve patient care. Homology has built foundational intellectual property on gene editing and gene therapy using vectors derived from naturally occurring human adeno-associated viruses (AAVs). The Company’s technology is precise, on-target and highly efficient for in vivo editing of genetic mutations. The unique team and technology create a significant opportunity for Homology to rapidly advance a diverse pipeline of new medicines that address and potentially cure the underlying cause of genetic diseases. For more information, please visit

Theresa McNeely
SVP, Corporate Communications & Patient Advocacy

Cara Mayfield Director
Corporate Communications
781-301-7277, ext. 141