Puretech Ownership
Product Candidate
Initial Indication(s)
Stage of Development
11.8% Equity
VOR33
Acute myeloid leukemia
Preclinical
Engineered hematopoietic stem cells that unleash the potential of targeted therapies

Founded by PureTech, Vor is developing cell therapies with broad potential for treating cancer. Vor’s key differentiation is a focus on technologies that can selectively target cancer cells without impacting normal cells. Engineered cells, such as chimeric antigen receptor (CAR) T cells, are now FDA-approved drugs for treating hematologic malignancies. However, these and similar technologies target both cancer and normal cells, causing substantial toxicities and limiting their potential. Vor is taking a fundamentally novel approach for targeting cancer selectively by developing engineered hematopoietic stem cells (HSCs). Vor’s engineered HSCs generate healthy, functional cells that are protected from depletion by cancer-targeted therapies.

Our platform is broad, and can be used to enhance the therapeutic window of several CAR-modified cells (such as CAR T-cells, CAR NK cells, and others), as well as other therapies such as antibody-drug conjugates or conventional antibodies. When combined with targeted therapies, this technology could enable transformative outcomes in patients with otherwise grim prognoses.

  • Program Discovery Process by the PureTech Team
    • PureTech was interested in approaches to treat hematological malignancies that currently have poor response rates or poor adverse event profiles despite recent advances in cell therapies and targeted therapies. PureTech engaged leading hematological cancer specialists and became aware of work from the laboratory of Vor scientific board chair, Siddhartha Mukherjee, MD, PhD, assistant professor of medicine at Columbia University and Pulitzer Prize-winning author of The Emperor of All Maladies: A Biography of Cancer and The Gene. Dr. Mukherjee pioneered the idea of genetically engineering stem cells to eliminate a particular target such that healthy stem cells and progeny cells would be spared from targeted cancer therapy. PureTech worked with Dr. Mukherjee on this intellectual property, which it exclusively in-licensed from Columbia in April 2016, and on advancing this concept through critical proof-of-concept (POC) experiments. PureTech has filed additional intellectual property (both in-licensed from Columbia and owned by Vor), assembling an excellent research team and completing a round of fundraising.
    • In July 2019, Bill Lundberg, MD, was appointed to Vor’s board of directors. Dr. Lundberg is the former chief scientific officer of CRISPR Therapeutics. In August 2019, Robert Ang, MBBS, MBA, was appointed president and chief executive officer of Vor. Dr. Ang is the former chief business officer of Neon Therapeutics.
  • Patient Need & Market Potential
    • The prognosis for relapsed and refractory blood-borne malignancies is very poor and can be measured in a few months, depending on patient-specific risk factors. For example, for acute myeloid leukemia (AML) which affects approximately 60,000 patients at any one time in the United States, only about 30 percent of patients with active disease following a bone marrow transplant survive past 12 months.
    • Targeted therapies, such as CAR-T cells and bispecific antibodies, antibody-drug conjugates and conventional mAbs, have shown excellent  outcomes, particularly in patients with certain hematologic malignancies expressing B-cell markers. However, these targeted therapies frequently target both cancer and normal cells, causing substantial toxicities and limiting their potential. There is a need for new strategies that can enable selectively targeting cancer cells without impacting a patient’s normal cells.
  • Innovative Approach to Solving the Problem
    • Vor’s differentiated approach is designed to enable broad targeting of lineage antigens, which are attractive targets but face serious limitations, since they are expressed on both healthy cells and cancerous cells.
    • Vor’s eHSCs do not display a particular antigen, therefore making these antigens tumor-specific and potentially safer to target while protecting the healthy blood cells from depletion. This enables maximal targeted therapy doses to be administered without fear of on-target toxicity. Vor’s approach may also enable new targeted therapies to be developed that otherwise would be too toxic to consider developing.
    • Vor’s technology is enabled via gene editing of hematopoietic stem cells, generating eHSCs which can be transplanted into patients as part of standard transplant procedures. Transplants can be performed prior to the targeted therapy or the targeted therapy can be used prior to the hematopoietic stem cell transplantation. By using Vor’s approach the population of potential target antigens could potentially be expanded beyond tumor-specific antigens such as neoantigens or B-cell antigens, for example CD19, to antigens which are present in broad ranges of hematological malignancies.
    • Vor’s platform can potentially be used to improve the safety profile of targeted therapies, such as antibody drug conjugates, bispecific antibodies, chimeric antigen receptor T (CAR-T) cells and others, expanding their reach beyond B-cell malignancies to other myeloid leukemia, such as AML, as well as enhancing the effectiveness of similar therapies. When combined with targeted therapies, this technology could potentially enable transformative outcomes in patients with otherwise grim prognoses.
    • Vor’s lead product candidate, VOR33, is a novel hematopoietic stem cells (HSC) therapy in development for AML consisting of donor-derived HSCs that are engineered to lack the cell surface protein CD33. When removed from the cell surface, VOR33 engineered hematopoietic stem cells (eHSCs) lack cell surface expression of CD33, do not appear to have any measurable changes to their biological function and have been shown to be highly resistant to attack from CD33-targeted therapies. When infused into a patient, these eHSCs are designed to mature and differentiate into a full spectrum of healthy immune and blood cells that would be unaffected by the cancer treatment. This approach has the potential to minimize targeted therapy toxicities and maximize the potency of anti-CD33 therapies for treating AML.
  • Milestones Achieved
    • In May 2019, preclinical research was published in the scientific journal Proceedings of the National Academy of Sciences supporting Vor’s novel approach to treating cancer via eHSCs.
    • Vor has achieved ex vivo POC for its technology and received validation of its technology in engineered humanized mouse models.
    • In the January 2020 post-period, Vor held a pre-IND meeting with the FDA to gather important feedback to assemble the data package necessary for a potential IND filing.

Vor’s platform can potentially be used to improve the safety profile of targeted therapies, such as antibody drug conjugates, bispecific antibodies and chimeric antigen receptor T (CAR-T) cells and others, expanding their reach beyond B-cell malignancies to other myeloid leukemia, such as AML, as well as enhancing the effectiveness of similar therapies. When combined with targeted therapies, this technology could potentially enable transformative outcomes in patients with otherwise grim prognoses.


Vor's eHSC technology