Magenta Therapeutics said today it has doubled its money with a $50 million Series B round led by GV, formerly Google Ventures. The Cambridge, MA-based startup spun out of Harvard University last year with nearly $50 million in launch money to develop improved bone marrow transplants.
Magenta has also licensed a drug from Novartis that it says could help boost the number of healthy stem cells that are delivered into a patient’s body, a key procedure in a transplant.
Used to treat people with cancer and other blood-borne diseases, a bone marrow transplant starts with a procedure to kill a patient’s diseased blood stem cells, which live in the bone marrow. The diseased cells are then replaced with healthy stem cells, usually from a donor. Though growing safer, it’s still a risky process, especially for elderly or frail patients. Deaths related to the treatment have dropped below 20 percent in recent years, but Magenta’s founders as well as researchers at Stanford University are among the groups working to improve the complicated steps.
Magenta is developing three types of drugs, each for a different procedure in the transplant process. It will test them as separate products but try to market them as a suite to transplant clinics, according to management.
The drug Magenta licensed from Novartis is applied to cells from donated umbilical cord blood, which have different properties than cells from blood donated by adults. The drug, which recently completed an early stage study, is meant to stimulate the blood cells to replicate faster outside the body, providing a bigger population to put back into the patient. The more cells, the better the chance that the new healthy cells will “engraft,” or survive in the patient’s bone marrow.
Magenta also aims to develop an alternative to chemotherapy or radiation, which a patient receives before a transplant to kill his or her diseased stem cells; and a treatment to coax an adult donor’s stem cells out of the bone marrow and into the bloodstream, where the cells are easier to harvest for the transplant.
Other investors in the new round are previous backers Third Rock Ventures, Atlas Venture, Partners Innovation Fund, and Access Industries, and new investors including Casdin Capital and BeTheMatch BioTherapies, which is affiliated with the nonprofit international bone marrow registry NMDP/Be The Match.
Magenta said it would work with BeTheMatch BioTherapies on research and development.