FDA Approval Summary: Lisocabtagene Maraleucel for Second-Line Treatment of Large B-Cell Lymphoma.

In June 2022, the FDA extended the indication for lisocabtagene maraleucel (liso-cel) to include adults with large B-cell lymphoma (LBCL) who have refractory disease or relapse within 12 months of first-line chemoimmunotherapy (CIT), as well as transplant-ineligible adults with refractory disease or relapse after first-line CIT. Two clinical trials evaluating a single infusion of liso-cel preceded by lymphodepleting chemotherapy supported the second-line indications. TRANSFORM is a randomized, phase 3, open-label trial comparing liso-cel with standard second-line therapy, including planned autologous hematopoietic stem cell transplantation (HSCT), in 184 transplant-eligible patients. On interim analysis, event-free survival (EFS) by independent review committee (IRC) assessment was statistically significantly improved for the liso-cel arm, with a stratified hazard ratio of 0.34 [95% confidence interval (CI), 0.22-0.51; P < 0.0001]; the estimated median EFS was 10.1 months in the liso-cel arm versus 2.3 months in the control arm. PILOT is a single-arm phase 2 trial of second-line liso-cel in patients who were transplant-ineligible due to age or comorbidities but had adequate organ function for chimeric antigen receptor (CAR) T-cell therapy. Among 61 patients who received liso-cel (median age, 74 years), the IRC-assessed complete response rate was 54% (95% CI, 41-67). Among patients achieving complete response, the estimated 1-year rate of continued response was 68% (95% CI, 45-83). Of the 268 patients combined who received liso-cel as second-line therapy for LBCL, cytokine release syndrome occurred in 45% (Grade 3, 1.3%) and CAR T-cell-associated neurologic toxicities occurred in 27% (Grade 3, 7%), warranting a continued risk evaluation and mitigation strategy.

FDA Approval Summary: Pirtobrutinib for Relapsed or Refractory Mantle Cell Lymphoma.

In January 2023, the FDA granted accelerated approval to pirtobrutinib for the treatment of adult patients with relapsed or refractory mantle cell lymphoma (MCL) after at least two lines of systemic therapy, including a Bruton tyrosine kinase (BTK) inhibitor. Approval was based on BRUIN, a single-arm study of pirtobrutinib monotherapy in patients with B-cell malignancies. Efficacy was based on independent review committee-assessed overall response rate (ORR) supported by durability of response in 120 patients with relapsed or refractory MCL who had received a prior BTK inhibitor and received the approved pirtobrutinib dosage of 200 mg once daily. The ORR was 50% [95% confidence interval (CI), 41-59], and the complete response rate was 13% (95% CI, 7-20), with an estimated median duration of response of 8.3 months. The most common nonhematologic adverse reactions were fatigue, musculoskeletal pain, diarrhea, edema, dyspnea, pneumonia, and bruising. Warnings and Precautions in labeling include infection, hemorrhage, cytopenias, atrial arrhythmias, and second primary malignancies. Postmarketing studies were required to evaluate longer-term safety of pirtobrutinib and to verify the clinical benefit of pirtobrutinib. This article summarizes key aspects of the regulatory review, including the indication statement, efficacy and safety considerations, and postmarketing requirements.

FDA Approval Summary: Axicabtagene Ciloleucel for Second-Line Treatment of Large B-Cell Lymphoma.

In April 2022, the FDA approved axicabtagene ciloleucel (axi-cel) for adults with large B-cell lymphoma (LBCL) that is refractory to first-line chemoimmunotherapy or that relapses within 12 months of first-line chemoimmunotherapy. Approval was based on ZUMA-7, a randomized (1:1), open-label trial in 359 patients with primary refractory LBCL (74%) or early relapse who were transplant candidates. The study compared a single course of axi-cel to standard therapy, consisting of chemoimmunotherapy followed by high-dose therapy and autologous hematopoietic stem cell transplantation (HSCT) in responding patients. Overall, 94% of the experimental arm received chimeric antigen receptor (CAR) T-cell product, and 35% of the control arm received on-protocol HSCT. The primary endpoint was event-free survival, which was significantly longer in the axi-cel arm with an HR of 0.40 (95% confidence interval, 0.31-0.51; P value < 0.0001) and estimated median of 8.3 months, versus 2.0 months with standard therapy. Among 168 recipients of axi-cel, cytokine release syndrome occurred in 92% (Grade ≥ 3, 7%), neurologic toxicity in 74% (Grade ≥ 3, 25%), prolonged cytopenias in 33%, and fatal adverse reactions in 1.8%. This is the first FDA approval of a CAR T-cell therapy for LBCL in the second-line setting and reflects a potential paradigm shift.

Minimal Residual Disease Data in Hematologic Malignancy Drug Applications and Labeling: An FDA Perspective.

Minimal residual disease (MRD) is increasingly used as a prognostic biomarker, a measure of clinical efficacy, and a guide for treatment decisions in various hematologic malignancies. We sought to characterize MRD data in registrational trials in hematologic malignancies submitted to the U.S. Food and Drug Administration (FDA) with the ultimate goal of expanding the utility of MRD data in future drug applications. We descriptively analyzed MRD data collected in registrational trials, including the type of MRD endpoint, assay, disease compartment(s) assessed, and the acceptance of MRD data in the U.S. prescribing information (USPI). Of 196 drug applications submitted between January 2014 and February 2021, 55 (28%) included MRD data. Of the 55 applications, MRD data was proposed by the Applicant for inclusion in the USPI in 41 (75%) applications but was included in only 24 (59%). Despite an increasing number of applications that proposed to include MRD data in the USPI, the acceptance rate decreased over time. Although MRD data have the potential to expedite drug development, our analysis identified challenges and specific areas for improvement, including assay validation, standardization of collection methods to optimize performance, and considerations in trial design and statistical methodology.

FDA approval summary: Crizotinib for pediatric and young adult patients with relapsed or refractory systemic anaplastic large cell lymphoma.

In January 2021, the U.S. Food and Drug Administration (FDA) approved crizotinib for pediatric patients 1 year and older and young adults with relapsed or refractory systemic anaplastic large cell lymphoma (sALCL). This is the first approval for pediatric sALCL. Approval was based on a single-arm trial of crizotinib monotherapy that included 26 patients, aged 1-20 years, with previously treated sALCL. Efficacy was based on centrally assessed objective response rate (88%) and duration of response. Herein, we highlight unique aspects of the regulatory review, including extension of the indication to young adults, postmarketing safety, and dose optimization strategies.

FDA Approval Summary: Axicabtagene Ciloleucel for Relapsed or Refractory Follicular Lymphoma.

In March 2021, the U.S. Food and Drug Administration granted accelerated approval to axicabtagene ciloleucel, a CD19-directed chimeric antigen receptor T-cell therapy, for the treatment of adult patients with relapsed or refractory follicular lymphoma (r/r FL) after at least 2 lines of systemic therapy. Approval was based on ZUMA-5, a single-arm, open-label, multicenter trial that evaluated a single infusion of axicabtagene ciloleucel, preceded by lymphodepleting chemotherapy with cyclophosphamide and fludarabine, in this population. Efficacy was based on objective response rate (ORR) and duration of response (DOR) as determined by an independent review committee. Among 81 patients in the primary efficacy analysis, having a median of 3 (range 2-9) prior lines of systemic therapy, the ORR was 91% (95% confidence interval [CI]: 83-96) with a complete remission (CR) rate of 60% and a median time-to-response of 1 month. The median DOR was not reached, and the 1-year rate of continued remission was 76% (95% CI: 64-85). For all leukapheresed patients with FL in this trial (n = 123), the ORR was 89% (95% CI: 83-94) with a CR rate of 62%. Among 146 patients with indolent lymphoma evaluated for safety, cytokine release syndrome occurred in 84% (Grade ≥3, 8%) and neurological toxicities occurred in 77% (Grade ≥3, 21%), leading to implementation of a risk evaluation and mitigation strategy. Serious adverse reactions occurred in 48%. Post-marketing studies will further evaluate clinical benefit in patients with r/r FL and long-term safety.

HLA informs risk predictions after haploidentical stem cell transplantation with posttransplantation cyclophosphamide.

Hematopoietic cell transplantation from HLA-haploidentical related donors is increasingly used to treat hematologic cancers; however, characteristics of the optimal haploidentical donor have not been established. We studied the role of donor HLA mismatching in graft-versus-host disease (GVHD), disease recurrence, and survival after haploidentical donor transplantation with posttransplantation cyclophosphamide (PTCy) for 1434 acute leukemia or myelodysplastic syndrome patients reported to the Center for International Blood and Marrow Transplant Research. The impact of mismatching in the graft-versus-host vector for HLA-A, -B, -C, -DRB1, and -DQB1 alleles, the HLA-B leader, and HLA-DPB1 T-cell epitope (TCE) were studied using multivariable regression methods. Outcome was associated with HLA (mis)matches at individual loci rather than the total number of HLA mismatches. HLA-DRB1 mismatches were associated with lower risk of disease recurrence. HLA-DRB1 mismatching with HLA-DQB1 matching correlated with improved disease-free survival. HLA-B leader matching and HLA-DPB1 TCE-nonpermissive mismatching were each associated with improved overall survival. HLA-C matching lowered chronic GVHD risk, and the level of HLA-C expression correlated with transplant-related mortality. Matching status at the HLA-B leader and HLA-DRB1, -DQB1, and -DPB1 predicted disease-free survival, as did patient and donor cytomegalovirus serostatus, patient age, and comorbidity index. A web-based tool was developed to facilitate selection of the best haploidentical-related donor by calculating disease-free survival based on these characteristics. In conclusion, HLA factors influence the success of haploidentical transplantation with PTCy. HLA-DRB1 and -DPB1 mismatching and HLA-C, -B leader, and -DQB1 matching are favorable. Consideration of HLA factors may help to optimize the selection of haploidentical related donors.

Guidelines for Reporting Trial Protocols and Completed Trials Modified Due to the COVID-19 Pandemic and Other Extenuating Circumstances: The CONSERVE 2021 Statement.

Importance: Extenuating circumstances can trigger unplanned changes to randomized trials and introduce methodological, ethical, feasibility, and analytical challenges that can potentially compromise the validity of findings. Numerous randomized trials have required changes in response to the COVID-19 pandemic, but guidance for reporting such modifications is incomplete. Objective: As a joint extension for the CONSORT and SPIRIT reporting guidelines, CONSERVE (CONSORT and SPIRIT Extension for RCTs Revised in Extenuating Circumstances) aims to improve reporting of trial protocols and completed trials that undergo important modifications in response to extenuating circumstances. Evidence: A panel of 37 international trial investigators, patient representatives, methodologists and statisticians, ethicists, funders, regulators, and journal editors convened to develop the guideline. The panel developed CONSERVE following an accelerated, iterative process between June 2020 and February 2021 involving (1) a rapid literature review of multiple databases (OVID Medline, OVID EMBASE, and EBSCO CINAHL) and gray literature sources from 2003 to March 2021; (2) consensus-based panelist meetings using a modified Delphi process and surveys; and (3) a global survey of trial stakeholders. Findings: The rapid review yielded 41 673 citations, of which 38 titles were relevant, including emerging guidance from regulatory and funding agencies for managing the effects of the COVID-19 pandemic on trials. However, no generalizable guidance for all circumstances in which trials and trial protocols might face unanticipated modifications were identified. The CONSERVE panel used these findings to develop a consensus reporting guidelines following 4 rounds of meetings and surveys. Responses were received from 198 professionals from 34 countries, of whom 90% (n = 178) indicated that they understood the concept definitions and 85.4% (n = 169) indicated that they understood and could use the implementation tool. Feedback from survey respondents was used to finalize the guideline and confirm that the guideline's core concepts were applicable and had utility for the trial community. CONSERVE incorporates an implementation tool and checklists tailored to trial reports and trial protocols for which extenuating circumstances have resulted in important modifications to the intended study procedures. The checklists include 4 sections capturing extenuating circumstances, important modifications, responsible parties, and interim data analyses. Conclusions and Relevance: CONSERVE offers an extension to CONSORT and SPIRIT that could improve the transparency, quality, and completeness of reporting important modifications to trials in extenuating circumstances such as COVID-19.

FDA Approval Summary: Selinexor for Relapsed or Refractory Diffuse Large B-Cell Lymphoma.

In June 2020, the U.S. Food and Drug Administration granted accelerated approval to selinexor for the treatment of adult patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL), not otherwise specified, including DLBCL arising from follicular lymphoma, after at least two lines of systemic therapy. Approval was based on SADAL, a multicenter trial of selinexor monotherapy in patients with DLBCL after two to five systemic regimens. Efficacy was based on independent review committee-assessed objective response rate (ORR) and duration of response using Lugano criteria. In 134 patients treated with the approved dosage (60 mg orally on days 1 and 3 of each week), the ORR was 29% (95% confidence interval, 22-38), with complete response in 13% and with 38% of responses lasting at least 6 months. Gastrointestinal toxicity developed in 80% of patients, hyponatremia in 61%, central neurological toxicity (such as dizziness and mental status changes) in 25%, and ocular toxicity in 18%. New or worsening grade 3 or 4 thrombocytopenia, lymphopenia, neutropenia, anemia, or hyponatremia developed in ≥15%. Adverse reactions led to selinexor dose interruption in 61% of patients, dose reduction in 49%, and permanent discontinuation in 17%, with thrombocytopenia being the leading cause of dose modifications. Postmarketing studies will evaluate reduced dosages of selinexor and further evaluate clinical benefit in patients with relapsed or refractory DLBCL. IMPLICATIONS FOR PRACTICE: Selinexor is a new potential option for adults with relapsed or refractory diffuse large B-cell lymphoma, not otherwise specified, in the third-line setting or beyond. Toxicities are typically manageable but can be difficult to tolerate and necessitate close monitoring and supportive care.

Allogeneic bone marrow transplantation with post-transplant cyclophosphamide for patients with HIV and haematological malignancies: a feasibility study.

BACKGROUND: Allogeneic blood or marrow transplantation (alloBMT) is a potentially life-saving treatment for individuals with HIV and haematological malignancies; challenges include identifying donors and maintaining antiretroviral therapy (ART). The objectives of our study were to investigate interventions to expand donor options and to prevent ART interruptions for patients with HIV in need of alloBMT. METHODS: This single-arm, interventional trial took place at the Johns Hopkins Sidney Kimmel Comprehensive Cancer Center (Baltimore, MD, USA). Individuals with HIV who were at least 18 years of age and referred for alloBMT for a standard clinical indication were eligible. The only exclusion criterion was a history of documented resistance to enfuvirtide. We used post-transplant cyclophosphamide as graft-versus-host disease (GVHD) prophylaxis to expand donor options and an optimised ART strategy of avoiding pharmacoenhancers and adding subcutaneous enfuvirtide during post-transplant cyclophosphamide and during oral medication intolerance. Our primary outcome was the proportion of participants who maintained ART through day 60 after alloBMT. We measured the HIV latent reservoir using a quantitative viral outgrowth assay. This study is registered on ClinicalTrials.gov, NCT01836068. FINDINGS: Between June 1, 2013, and August 27, 2015, nine patients who were referred for transplant provided consent. Two patients had relapsed malignancy before donor searches were initiated. Seven patients had suitable donors identified (two matched sibling, two matched unrelated, two haploidentical, and one single-antigen mismatched unrelated) and proceeded to alloBMT. All patients maintained ART through day 60 and required ART changes (median 1, range 1-3) in the first 90 days. One patient stopped ART and developed HIV rebound with grade 4 meningoencephalitis at day 146. Among six patients who underwent alloBMT and had longitudinal measurements available, the HIV latent reservoir was not detected post-alloBMT in four patients with more than 95% donor chimerism, consistent with a 2·06-2·54 log10 reduction in the HIV latent reservoir. In the two patients with less than 95% donor chimerism, the HIV latent reservoir remained stable. INTERPRETATION: By using post-transplant cyclophosphamide as GVHD prophylaxis, we successfully expanded alloBMT donor options for patients with HIV. Continuing ART with a regimen that includes enfuvirtide post-alloBMT was safe, but life-threatening viral rebound can occur with ART interruption. FUNDING: amfAR (the Foundation for AIDS Research), Johns Hopkins University Center for AIDS Research, and National Cancer Institute.

FDA Approval Summary: Mogamulizumab-kpkc for Mycosis Fungoides and Sézary Syndrome.

The FDA-approved mogamulizumab-kpkc, a CC chemokine receptor type 4 (CCR4)-directed mAb, in August 2018 for treatment of adult patients with relapsed or refractory mycosis fungoides or Sézary syndrome after at least one prior systemic therapy. Regular approval was based on a randomized, open-label trial that randomized 372 such patients, with a median of 3 prior systemic therapies, to either mogamulizumab-kpkc or vorinostat. Investigator-assessed progression-free survival (PFS) was statistically significantly longer in the mogamulizumab-kpkc arm, which had an estimated median PFS of 7.6 months [95% confidence interval (CI), 5.6-10.2] compared with 3.1 months (95% CI, 2.8-4.0) in the vorinostat arm (HR = 0.53; 95% CI, 0.41-0.69). The confirmed overall response rate was 28% and 5%, respectively (P < 0.001), based on global composite response criteria. Adverse reactions occurring in at least 20% of mogamulizumab-kpkc recipients included rash, infusion-related reactions, fatigue, diarrhea, musculoskeletal pain, and upper respiratory tract infection. Serious adverse reactions occurred in 36% of patients, most often from infection. The prescribing information includes warnings for dermatologic toxicity, infusion reactions, infections, autoimmune complications, and complications of allogeneic hematopoietic stem cell transplantation, including severe and steroid-refractory graft-versus-host disease.See related commentary by Larocca et al., p. 7272.

FDA Approval Summary: Brentuximab Vedotin in First-Line Treatment of Peripheral T-Cell Lymphoma.

In November 2018, the U.S. Food and Drug Administration (FDA) approved brentuximab vedotin (BV) for the treatment of adult patients with previously untreated systemic anaplastic large cell lymphoma or other CD30-expressing peripheral T-cell lymphomas (PTCL), including angioimmunoblastic T-cell lymphoma and PTCL not otherwise specified, in combination with cyclophosphamide, doxorubicin, and prednisone (CHP). Approval was based on ECHELON-2, a randomized, double-blind, actively controlled trial that compared BV+CHP with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) in 452 patients with newly diagnosed, CD30-expressing PTCL. Efficacy was based on independent review facility-assessed progression-free survival (PFS). The median PFS was 48.2 months with BV+CHP versus 20.8 months with CHOP, resulting in a hazard ratio (HR) of 0.71 (95% confidence interval [CI]: 0.54-0.93). The trial also demonstrated improvement in overall survival (HR 0.66; 95% CI: 0.46-0.95), complete response rate (68% vs. 56%), and overall response rate (83% vs. 72%) with BV+CHP. The most common adverse reactions (incidence ≥20%) observed ≥2% more with BV+CHP were nausea, diarrhea, fatigue or asthenia, mucositis, pyrexia, vomiting, and anemia. Peripheral neuropathy rates were similar (52% with BV+CHP, 55% with CHOP). Through the Real-Time Oncology Review pilot program, which allows FDA early access to key data, FDA granted this approval less than 2 weeks after official submission of the application. IMPLICATIONS FOR PRACTICE: This is the first U.S. Food and Drug Administration approval for treatment of patients with newly diagnosed peripheral T-cell lymphomas (PTCL). Improvement in progression-free and overall survival over cyclophosphamide, doxorubicin, vincristine, and prednisone chemotherapy, which has been the standard of care for decades, is unprecedented. The new regimen represents a major advance for the frontline treatment of patients with CD30-expressing PTCL.

FDA Approval Summary: Axicabtagene Ciloleucel for Relapsed or Refractory Large B-cell Lymphoma.

In October 2017, the FDA granted regular approval to axicabtagene ciloleucel, a CD19-directed chimeric antigen receptor (CAR) T-cell therapy, for treatment of adult patients with relapsed or refractory large B-cell lymphoma after two or more lines of systemic therapy. Efficacy was based on complete remission (CR) rate and duration of response (DOR) in 101 adult patients with relapsed or refractory large B-cell lymphoma (median 3 prior systemic regimens) treated on a single-arm trial. Patients received a single infusion of axicabtagene ciloleucel, preceded by lymphodepleting chemotherapy with cyclophosphamide and fludarabine. The objective response rate per independent review committee was 72% [95% confidence interval (CI), 62-81], with a CR rate of 51% (95% CI, 41-62). With a median follow-up of 7.9 months, the median DOR was not reached in patients achieving CR (95% CI, 8.1 months; not estimable, NE), whereas patients with partial remission had an estimated median DOR of 2.1 months (95% CI, 1.3-5.3). Among 108 patients evaluated for safety, serious adverse reactions occurred in 52%. Cytokine release syndrome and neurologic toxicities occurred in 94% and 87% of patients, respectively, leading to implementation of a risk evaluation and mitigation strategy.

FDA Approval Summary: Midostaurin for the Treatment of Advanced Systemic Mastocytosis.

In April 2017, the U.S. Food and Drug Administration granted regular approval to midostaurin for the treatment of adult patients with aggressive systemic mastocytosis (ASM), systemic mastocytosis with associated hematological neoplasm (SM-AHN), or mast cell leukemia (MCL). Approval was based on results from CPKC412D2201, a single-arm trial of midostaurin (100 mg orally twice daily) in previously treated or untreated patients. For the patients with ASM and SM-AHN, efficacy was established on the basis of confirmed complete remission (CR) plus incomplete remission (ICR) by modified Valent criteria with six cycles of midostaurin. There were no CRs reported; ICR was achieved by 6 of 16 patients (38%; 95% confidence interval [CI]: 15%-65%) with ASM and by 9 of 57 patients (16%; 95% CI: 7%-28%) with SM-AHN. Within the follow-up period, the median duration of response was not reached for the patients with ASM (range, 12.1+ to 36.8+ months) or with SM-AHN (range, 6.6+ to 52.1+ months). For the patients with MCL, efficacy was established on the basis of confirmed CR using modified 2013 International Working Group-Myeloproliferative Neoplasms Research and Treatment-European Competence Network on Mastocytosis criteria. Of 21 patients with MCL, 1 (5%) achieved a CR. Of 142 patients with SM evaluated for safety, 56% had dose modifications for toxicity, and 21% discontinued treatment due to a toxicity. Over 50% reported nausea, vomiting, or diarrhea, and ≥30% reported edema, musculoskeletal pain, fatigue, abdominal pain, or upper respiratory tract infection. New or worsening grade ≥3 lymphopenia, anemia, thrombocytopenia, or neutropenia developed in ≥20%. Although midostaurin is an active drug for treatment of advanced SM, it is not clear that the optimal dose has been identified. IMPLICATIONS FOR PRACTICE: Midostaurin is the only U.S. Food and Drug Administration-approved therapy for patients with systemic mastocytosis with associated hematological neoplasm and mast cell leukemia and is the only therapy approved for patients with aggressive systemic mastocytosis regardless of KIT D816V mutation status. Based on response rate and duration, midostaurin has meaningful clinical activity in these rare, life-threatening diseases.

Pilot trial of K562/GM-CSF whole-cell vaccination in MDS patients.

Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal hematopoietic stem cell malignancies. Currently, approved drugs are given with non-curative intent as the only known cure is allogeneic bone marrow transplantation, which relies on the donor's immune system driving an allogeneic effect. Previous efforts to harness the endogenous immune system have been less successful. We present the results of a pilot study of K562/GM-CSF (GVAX) whole-cell vaccination in MDS patients. The primary objective of safety was met as there were no serious adverse events. One patient had a decrease in transfusion requirements and another demonstrated hematologic improvement suggesting a signal for clinical activity. In vitro correlative studies indicated biological effects on immune cells following vaccination. Although only a pilot study, results are encouraging that an immunotherapeutic approach with a whole-cell vaccine may be feasible in MDS patients.

Haploidentical Bone Marrow Transplantation with Post-Transplant Cyclophosphamide Using Non-First-Degree Related Donors.

Outcomes of nonmyeloablative (NMA) haploidentical (haplo) blood or marrow transplant (BMT) with post-transplantation cyclophosphamide (PTCy) using non-first-degree relatives are unknown. We evaluated 33 consecutive adult patients (median age, 56 years) with hematologic malignancies who underwent NMA haplo T cell-replete BMT with PTCy at Johns Hopkins using second- or third-degree related donors. Donors consisted of 10 nieces (30%), 9 nephews (27%), 7 first cousins (21%), 5 grandchildren (15%), and 2 uncles (6%). Thirty-one patients (94%) reached full donor chimerism by day 60. The estimated cumulative incidence (CuI) of grades II to IV acute graft-versus-host disease (aGVHD) at day 180 was 24% (90% confidence interval [CI], 9% to 38%). Only 1 patient experienced grades III to IV aGVHD. At 1 year the CuI of chronic GVHD was 10% (90% CI, 0% to 21%). The CuI of nonrelapse mortality at 1 year was 5% (90% CI, 0% to 14%). At 1 year the probability of relapse was 31% (90% CI, 12% to 49%), progression-free survival 64% (90% CI, 48% to 86%), and overall survival 95% (90% CI, 87% to 100%). The 1-year probability of GVHD-free, relapse-free survival was 57% (90% CI, 41% to 79%). NMA haplo BMT with PTCy from non-first-degree relatives is an acceptably safe and effective alternative donor platform, with results similar to those seen with first-degree relatives.

Shortened-Duration Tacrolimus after Nonmyeloablative, HLA-Haploidentical Bone Marrow Transplantation.

With post-transplantation cyclophosphamide (PTCy) as graft-versus-host disease (GVHD) prophylaxis, nonmyeloablative HLA-haploidentical (NMA haplo) and HLA-matched blood or marrow transplantation (BMT) have comparable outcomes. Early discontinuation of immunosuppression may reduce the risk of relapse and improve immune reconstitution, but may increase the risk of GVHD. We conducted a prospective trial of NMA haplo BMT for patients with hematologic malignancies (median age, 61 years), evaluating the safety of early discontinuation of tacrolimus. All patients received T cell-replete bone marrow followed by high-dose PTCy, mycophenolate mofetil, and tacrolimus. Tacrolimus was prespecified to stop without taper at day +90, +60, or +120, contingent on having ≥5% donor T cells, no relapse, and no grade II-IV acute or significant chronic GVHD. Safety stopping rules were based on ≥5% graft failure, ≥10% nonrelapse mortality (NRM), or a ≥20% combined incidence of severe acute and chronic GVHD from the tacrolimus stop date through day +180. Of the 47 patients in the day +90 arm, 23 (49%) stopped tacrolimus as planned. Of the 55 patients in the day +60 arm, 38 (69%) stopped as planned. Safety stopping criteria were not met. In both arms, at day +180, the probability of grade II-IV acute GVHD was <40%, that of grade III-IV acute GVHD was <8%, and that of NRM was <5%. The 1-year probabilities of chronic GVHD and NRM were <15% and <10%, respectively, in both arms. The 1-year GVHD-free relapse-free survival was higher in the day 60 arm. Thus, stopping tacrolimus as early as day +60 is feasible and carries acceptable risks after NMA haplo BMT with PTCy. This approach may facilitate post-transplantation strategies for relapse reduction.