A check-in study with cancer patients who had blood or marrow transplants three years ago showed that they’re doing better than similar patients have done in the past. The group of 80 patients have something in common besides being trial participants. They didn’t have a matched 8/8 donor available when they needed a transplant. Because of this, they received blood or marrow transplant using mismatched unrelated donors (MMUD) with HLA matches from 7/8 down to as low as 4/8 using a new strategy to minimize the risk of using MMUD. This strategy uses post-transplant cyclophosphamide (PTCy) to reduce the higher risk of graft versus host disease (GVHD) associated with MMUD.
The original study looked at outcomes one year after transplant. This update looked at the patients’ overall survival rate at three years after transplant — ranging from 63% (patients with 4/8-6/8 HLA matched donors) to 71% (patients with 7/8 matched donors). These results exceeded researcher’s expectations for using mismatched unrelated donors.
Patients in the study were divided into two groups. The first group had myeloablative (intensive) conditioning. The second group had reduced intensity conditioning before transplant. Patients in the second group had better overall survival at 70% compared to 62% in the first group. The first group had higher rates of the cancer coming back (relapse). Researchers think this may be due to the patients in this group having higher risk disease in the first place.
Patients who received myeloablative conditioning had a rate of nonrelapse mortality (death due to complications other than the cancer coming back) of 10% and a rate of severe chronic GVHD of 12.5%. This can be compared to the reduced intensity conditioning group, which had a rate of non-relapse mortality of 15% and severe chronic GVHD rate of 5%
What does all this mean?
The data from the updated study provides even more evidence that patients who have MMUD blood or marrow transplant with a PTCy-based GVHD prevention strategy have very good outcomes at three years after transplant. Especially patients who have reduced intensity conditioning. This is important because it signifies that using mismatched donors can result in promising outcomes for patients. In other words, the transplant community has reassurance that patients who don’t have an 8/8 match can be safely transplanted. We’re one step closer to equal outcomes for all.
Learn more by reviewing a comprehensive analysis and description of the study.