HLA-haploidentical vs matched unrelated donor transplants with posttransplant cyclophosphamide-based prophylaxis.

Posttransplant cyclophosphamide (PTCy) graft-versus-host disease (GVHD) prophylaxis has enabled haploidentical (Haplo) transplantation to be performed with results similar to those after matched unrelated donor (MUD) transplantation with traditional prophylaxis. The relative value of transplantation with MUD vs Haplo donors when both groups receive PTCy/calcineurin inhibitor/mycophenolate GVHD prophylaxis is not known. We compared outcomes after 2036 Haplo and 284 MUD transplantations with PTCy GVHD prophylaxis for acute leukemia or myelodysplastic syndrome in adults from 2011 through 2018. Cox regression models were built to compare outcomes between donor types. Recipients of myeloablative and reduced-intensity regimens were analyzed separately. Among recipients of reduced-intensity regimens, 2-year graft failure (3% vs 11%), acute grades 2 to 4 GVHD (hazards ratio [HR], 0.70; P = .022), acute grades 3 and 4 GVHD (HR, 0.41; P = .016), and nonrelapse mortality (HR, 0.43; P = .0008) were lower after MUD than with Haplo donor transplantation. Consequently, disease-free (HR, 0.74; P = .008; 55% vs 41%) and overall (HR, 0.65; P = .001; 67% vs 54%) survival were higher with MUD than with Haplo transplants. Among recipients of myeloablative regimens, day-100 platelet recovery (95% vs 88%) was higher and grades 3 and 4 acute (HR, 0.39; P = .07) and chronic GVHD (HR, 0.66; P = .05) were lower after MUD than with Haplo donor transplantation. There were no differences in graft failure, relapse, nonrelapse mortality, and disease-free and overall survival between donor types with myeloablative conditioning regimens. These data extend and confirm the importance of donor-recipient HLA matching for allogeneic transplantation. A MUD is the preferred donor, especially for transplantations with reduced-intensity conditioning regimens.

Intermittent zoledronic Acid prevents bone loss in adults after allogeneic hematopoietic cell transplantation.

Bone mineral density (BMD) loss is common in survivors of allogeneic hematopoietic cell transplantation (alloHCT). We performed a multicenter, phase II, randomized open-label trial of intravenous zoledronic acid (ZA) to prevent BMD loss in adult recipients of alloHCT with osteopenia before HCT. The treatment group received ZA 4 mg intravenously within 28 days pre-HCT and at 3 and 6 months after HCT. Both treatment and control groups received calcium carbonate and vitamin D supplements. Of 61 patients, 32 were randomized to the ZA cohort and 29 to the control cohorts. More patients in the ZA group had an HCT comorbidity index high-risk score of ≥3 (50% versus 21%, P < .01). Baseline BMD, T-scores, serum osteocalcin, bone alkaline phosphatase, and urine N-telopeptide (UNTX) levels were similar in both cohorts. Thirty patients were evaluable for outcomes (11 from the treatment and 19 from the control group). At 12 months, subjects in the treatment group had an improvement in BMD at the femoral neck (mean change, .018 for ZA group versus -.054 for controls; P = .04) and a significant decline in levels of UNTX (-56 for ZA group versus -9 for control; P = .04) compared with baseline. ZA was well tolerated and not associated with any cases of osteonecrosis of jaw or renal impairment. Lower survival observed in the ZA cohort was likely related to baseline imbalance in HCT-CI scores. Intermittent ZA is effective in preserving long-term bone health in adult alloHCT recipients at risk for osteoporosis.