CAR-T treatments and other immunotherapies have changed the treatment of some blood cancers, but they can target healthy cells as well as cancer cells, causing nasty side effects. Vor Biopharma is working on an engineered stem cell solution, and it’s raised $110 million to move its lead program into the clinic.
The Cambridge, Massachusetts-based company is developing the treatment, VOR33, for patients with acute myeloid leukemia (AML) whose disease has worsened despite undergoing chemotherapy or a stem cell transplant.
“That’s the setting in which a lot of targeted agents are used. The trouble is, a great number of the targeted agents tend to fail—not because they are not efficacious, but because the drug is too toxic for the patient’s bone marrow,” Vor CEO Robert Ang told Fierce Biotech.
The drugs home in on healthy cells as well as cancerous ones because they express the same proteins. This leads to myelosuppression, which means the bone marrow doesn’t make enough white blood cells, platelets or red blood cells for the patient to survive, Ang said.
Vor’s treatment is made from hematopoietic, or blood-forming, stem cells from healthy donors. The company uses gene editing to get rid of cancer drug targets in those cells that are “biologically redundant,” which means deleting them doesn’t cause any harm. That target is CD33, in the case of VOR33.
“We’re trying to make the marrow treatment resistant such that the only cells that are expressing CD33 should be cancer cells,” Ang said. “We should be able to target them much more specifically, while minimizing the collateral damage that typically happens with these drugs.”
Vor believes its treatments could boost the reach of targeted therapies by improving their efficacy and increasing the amount of time patients can undergo those treatments.
And that’s not all. In addition to protecting these transplants and the blood cells they produce from targeted drugs, Vor thinks its approach could change the way we think about bone marrow transplant.
“To some degree, transplants have been relatively decentralized and less controlled … A lot of hospitals develop their own unique practices as to what they think works and how to handle cells and process them,” Ang said. “Our product will be regulated by the FDA, so we will be able to provide controls and the proper manufacturing steps to ensure we’re making the best quality product for patients.”
The series B will push VOR33 into clinical trials in the first half of 2021, a target the company’s on track to meet despite the COVID-19 pandemic. And Vor plans to expand its portfolio beyond CD33, starting with an “umbrella of targets” in the myeloid space, namely in acute myeloid leukemia, myelodysplastic syndromes and related diseases.
“But we are also looking beyond that to other cancers where there are similar potentially biologically redundant targets we could pursue,” said Ang, who took the company’s helm in August 2019.
Since then, Vor has grown from a staff of six to 50, and it’s about to move into new digs in west Cambridge as it moves VOR33 toward the clinic. It’s got the backing of RA Capital Management, Fidelity, 5AM Ventures, Johnson & Johnson Innovation, Osage University Partners, PureTech Health, the Pagliuca Family Office and Alexandria Venture Investments to do it all.