Translation of Clinical Research into Practice: An Impact Assessment of the Results from the Blood and Marrow Transplant Clinical Trials Network Protocol 0201 on Unrelated Graft Source Utilization

Applying Implementation Science in the Field of Transplant and Cellular Therapy

Implementation science (IS) is a systematic way to approach the broader adoption of evidence-based practices and has as its goal to understand and address the gap between research and practice, ensuring that research findings are effectively translated into practice and policy to improve health outcomes and service. We describe the various facets of IS and their relevance to the field of hematopoietic cell transplantation and cellular therapy (HCT/CT) with an emphasis on health equity, community engagement, and systems approach. We also review the similarities and differences among clinical research, quality improvement, and IS. Additionally, we describe how the Center for International Blood and Marrow Transplant Research applies IS across various phases: dissemination, analyzing current practices, and developing implementation intervention strategies. This includes designing studies and evaluations, scaling up operations, and ensuring sustainability. Lastly, we discuss further applications of IS in HCT/CT including the application to prospective research studies, collaboration across the field, and standardization and adoption of best practices. The application of IS in HCT/CT is pivotal to bringing research benefits directly to all patients. Through partnership, open-mindedness, and a commitment to evidence-based practice, we can collectively ensure the greatest impact of research on improving patient outcomes following HCT/CT.

How do we improve the translation of new evidence into the practice of hematopoietic cell transplantation and cellular therapy?

The field of hematopoietic cell transplantation and cell therapy (HCT/CT) is advancing rapidly to bring an ever-expanding collection of potentially curative therapies to patients with malignant and non-malignant diseases. The impact of these therapies depends on our ability to implement them as new evidence becomes available to advance the quality of care. There is often a long delay between evidence development and adoption of therapies based on that evidence into clinical practice. In this review, we describe the potential factors based on an implementation framework that could act as facilitators or barriers to adoption of therapies in the context of HCT/CT. We highlight two examples, the first to showcase the efforts to improve the efficiency of adoption of new findings and accelerate improvement in care of HCT/CT patients and the second to discuss the challenges in real world implementation of chimeric antigen receptor T cell therapy. We conclude by reviewing strategies to improve translation of evidence and ways to measure their success.

Are We Making PROGRESS in Preventing Graft-versus-Host Disease and Improving Clinical Outcomes? Impact of BMT CTN 1301 Study Results on Clinical Practice

The need for prospective randomized clinical trials investigating novel graft-versus-host disease (GVHD) prevention strategies that include other clinical outcomes impacted by GVHD has been highlighted as a priority for the field of hematopoietic cell transplantation. A recently completed study through the Blood and Marrow Transplant Clinical Trials Network (BMT CTN 1301) comparing CD34+ selection and post-transplantation cyclophosphamide with tacrolimus/methotrexate (Tac/MTX) for GVHD prevention demonstrated no significant differences in the primary endpoint of chronic GVHD relapse-free survival among the 3 approaches. The trial did not demonstrate a superior approach compared with Tac/MTX; however, it did highlight several challenges in determining the best and most relevant approaches to clinical trial design, particularly in the context of current and ongoing changes in real-world practices. Here we review the results of BMT CTN 1301 and their implications for clinical practice and future clinical trial design.

The effectiveness of champions in implementing innovations in health care: a systematic review

BACKGROUND

Champions have been documented in the literature as an important strategy for implementation, yet their effectiveness has not been well synthesized in the health care literature. The aim of this systematic review was to determine whether champions, tested in isolation from other implementation strategies, are effective at improving innovation use or outcomes in health care.

METHODS

The JBI systematic review method guided this study. A peer-reviewed search strategy was applied to eight electronic databases to identify relevant articles. We included all published articles and unpublished theses and dissertations that used a quantitative study design to evaluate the effectiveness of champions in implementing innovations within health care settings. Two researchers independently completed study selection, data extraction, and quality appraisal. We used content analysis and vote counting to synthesize our data.

RESULTS

After screening 7566 records titles and abstracts and 2090 full text articles, we included 35 studies in our review. Most of the studies (71.4%) operationalized the champion strategy by the presence or absence of a champion. In a subset of seven studies, five studies found associations between exposure to champions and increased use of best practices, programs, or technological innovations at an organizational level. In other subsets, the evidence pertaining to use of champions and innovation use by patients or providers, or at improving outcomes was either mixed or scarce.

CONCLUSIONS

We identified a small body of literature reporting an association between use of champions and increased instrumental use of innovations by organizations. However, more research is needed to determine causal relationship between champions and innovation use and outcomes. Even though there are no reported adverse effects in using champions, opportunity costs may be associated with their use. Until more evidence becomes available about the effectiveness of champions at increasing innovation use and outcomes, the decision to deploy champions should consider the needs and resources of the organization and include an evaluation plan. To further our understanding of champions' effectiveness, future studies should (1) use experimental study designs in conjunction with process evaluations, (2) describe champions and their activities and (3) rigorously evaluate the effectiveness of champions' activities.

REGISTRATION

Open Science Framework ( https://osf.io/ba3d2 ). Registered on November 15, 2020.

A New Standard in Graft-versus-Host Disease Prophylaxis? An Introduction to Blood and Marrow Transplant Clinical Trials Network 1703

Effective immunosuppressive regimens to prevent the development of graft-versus-host disease (GVHD) are essential to the success of allogeneic hematopoietic cell transplantation (HCT). After revolutionizing haploidentical transplantation, post-transplantation cyclophosphamide (PTCy) is now being evaluated for HCT performed from related and unrelated donors. In this setting, 2 recent randomized studies have demonstrated lower rates of GVHD and superior GVHD-free, relapse-free survival with PTCy compared with conventional GVHD prophylaxis. The Blood and Marrow Transplant Clinical Trials Network (BMT CTN) is currently conducting a large, randomized phase III, multicenter trial (BMT CTN 1703) comparing PTCy/tacrolimus/mycophenolate mofetil to tacrolimus/methotrexate as GVHD prophylaxis regimens in reduced-intensity allogeneic HCT. Here we review the ongoing study, highlight its importance to the field, and explore the possible implications of its results on clinical practice.

Influence of HLA 1-3-locus mismatch and antithymocyte globulin administration in unrelated bone marrow transplantation

For patients without an HLA-matched donor, an HLA-mismatched unrelated donor (MMUD) has been considered as an alternative donor in allogeneic hematopoietic cell transplantation (allo-HCT). We conducted a nationwide retrospective study to compare the transplant outcomes among 1-, 2-, and 3-locus (allele/antigen) mismatched unrelated donors (1MMUD n = 2044, 2MMUD n = 492, and 3MMUD n = 73) in allo-HCT and to assess the impact of antithymocyte globulin (ATG) in allo-HCT from 1-3MMUD. 2MMUD and 3MMUD were independent significant adverse factors for grade III-IV acute graft-versus-host disease (GVHD) (hazard ratio [HR] 1.72, p < 0.001 and HR 2.48, p < 0.001), non-relapse mortality (NRM) (HR 1.47, p < 0.001 and HR 2.00, p < 0.001), and overall survival (OS) (HR 1.21, p = 0.0066 and HR 1.60, p = 0.0015). Conversely, the use of ATG was an independent favorable factor for grade III-IV acute GVHD (HR 0.43, p < 0.001), NRM (HR 0.51, p < 0.001), and OS (HR 0.74, p = 0.0012). On the other hand, HLA compatibility and the use of ATG were not associated with a risk of relapse. An interaction test between the number of HLA mismatches and the use of ATG revealed that the effect of ATG on NRM and OS in the 2MMUD group was significantly less than that in the 1MMUD group (HR 1.53, p = 0.036 and HR 2.34, p = 0.0046). This study indicated that the number of HLA mismatches and the use of ATG were significantly associated with not only GVHD, but also NRM and OS. Whereas the use of ATG could improve transplant outcomes in allo-HCT from 1MMUD, its effectiveness with 2MMUD and 3MMUD was limited.

Factors Associated With Successful Discontinuation of Immune Suppression After Allogeneic Hematopoietic Cell Transplantation

Importance

Immune suppression discontinuation is routinely attempted after allogeneic hematopoietic cell transplantation (HCT) and under current practices may lead to graft-vs-host disease (GVHD)-associated morbidity and death. However, the likelihood and predictive factors associated with successful immune suppression discontinuation after HCT are poorly understood.

Objectives

To examine factors associated with successful immune suppression discontinuation and risk for immune suppression discontinuation failure under conventional HCT approaches and develop a practical tool to estimate successful immune suppression discontinuation likelihood at the clinical point of care.

Design, Setting, and Participants

Using long-term follow-up data from 2 national Blood and Marrow Transplant Clinical Trial Network studies (N = 827), a multistate model was developed to investigate the probability and variables associated with immune suppression discontinuation success. The study began in July 2015, and analyses were completed in August 2019.

Main Outcomes and Measures

Immune suppression discontinuation and immune suppression discontinuation failure.

Results

Of the 827 patients included in the analysis, 456 were men (55.1%). Median age at transplant was 44 (range, <1-67) years. With median follow-up of 72 (range, 11-124) months, 20.0% of the patients were alive and not receiving immune suppression at 5 years. Older recipient age (adjusted odds ratio [aOR] of >50 vs <30 years, 0.27, 99% CI, 0.14-0.50; P < .001), mismatched unrelated donor (aOR, mismatched unrelated vs matched related, 0.37; 99% CI, 0.14-0.97; P = .008), peripheral blood graft (aOR of peripheral blood graft vs bone marrow, 0.46; 99% CI, 0.26-0.82; P < .001), and advanced stage disease (aOR of advanced vs early disease, 0.45; 99% CI, 0.23-0.86, P = 0.002), were significantly associated with decreased odds of immune suppression discontinuation. Failed attempts at immune suppression discontinuation (127 patients [37.1% of total immune suppression discontinuation events]) resulting in GVHD were significantly associated with use of peripheral blood stem cells (HR, 2.62; 99% CI, 1.30-5.29; P < .001), prior GVHD, and earlier immune suppression discontinuation attempts. Earlier immune suppression discontinuation was not associated with protection from cancer relapse after HCT (adjusted hazard ratio for discontinuation vs not, 1.95; 99% CI, 0.88-4.31; P = .03).Dynamic prediction models were developed to provide future immune suppression discontinuation probability according to individual patient characteristics.

Conclusions and Relevance

Successful immune suppression discontinuation is uncommon in the setting of peripheral blood stem cell grafts. The data suggest earlier attempts at ISD conferred no long-term benefit, given frequent ISD failure, limited subsequent success after initial failed ISD attempt, and no evidence of relapse reduction. Using a risk model-based clinical application, physicians may be able to identify individual patients' probability of successful immune suppression discontinuation.

Personalizing rabbit anti-thymocyte globulin therapy for prevention of graft-versus-host disease after allogeneic hematopoietic cell transplantation: is there an optimal dose?

The efficacy of anti-thymocyte globulin (ATG) as prophylaxis for graft-versus-host disease (GVHD) has been investigated by many clinical studies over the past decade, including some randomized controlled trials. Intriguingly, although ATG is commonly used as prophylaxis for GVHD, there is still controversy about the optimal dose of ATG for prophylaxis of GVHD after allogeneic hematopoietic cell transplantation (allo-HCT). Indeed, the dose and formulation of ATG, as well as the degree of clinical benefit, has varied among studies, which makes it difficult to fully determine the clinical benefit of ATG. The aim of this review is to summarize the information regarding the optimal ATG dose of each formulation according to stem cell source, and to discuss how best to determine the personalized optimal dose of ATG in each allo-HCT recipient.

Short-term clinical outcomes after HLA 1-locus mismatched uPBSCT are similar to that after HLA-matched uPBSCT and uBMT

In Japan, use of unrelated peripheral blood stem cell transplantation (uPBSCT) from HLA-mismatched unrelated donors has recently been approved. We compared outcomes between HLA-matched and 1-locus mismatched uPBSCT, as well as the impact of HLA disparity in uPBSCT and in unrelated bone marrow transplantation (uBMT). In total, 5862 uBMT recipients and 234 uPBSCT recipients were included. In terms of HLA allele disparity, 185 uPBSCT patients (79.1%) had no HLA mismatch, and 49 (20.9%) had 1-locus mismatch; in comparison, 3585 uBMT patients (61.2%) had no HLA mismatch, and 2277 (38.8%) had 1-locus mismatch. The impact of 1-locus mismatch as compared with match in uPBSCT was not significantly higher than in uBMT [hazard ratio (HR) = 1.02 and 1.27 for grade III-IV acute graft-versus-host disease, HR = 0.98 and 1.14 for non-relapse mortality, and HR = 0.87 and 1.06 for overall survival, respectively]. In conclusion, the impact of single-locus mismatch on short-term outcomes was comparable in uPBSCT and uBMT. Larger studies with longer follow-up are needed to assess long-term outcomes.

The case for plerixafor to replace filgrastim as the optimal agent to mobilize peripheral blood donors for allogeneic hematopoietic cell transplantation

Granulocyte colony-stimulating factor (G-CSF)-stimulated peripheral blood progenitor cells (G-PBs) from either a related or unrelated donor continue to be the preferred donor source for most allogeneic hematopoietic cell transplantation (HCT). Recently, the American Society for Blood and Marrow Transplantation has recommended marrow instead of G-PBs as an unrelated graft source due to its lower rate of chronic graft-versus-host disease (cGVHD). However, the use of marrow is limited by both clinical considerations (slower rate of engraftment and increased donor morbidity) and logistical considerations (use of operating room resources and increased physician utilization), so this recommendation has not been widely adopted. An optimal donor source would include the rapid engraftment characteristic and the low donor morbidity associated with G-PBs and a rate of cGVHD similar to or lower than that of marrow. Recent data suggest that plerixafor mobilized PBs (P-PBs) have the rapid engraftment characteristics of G-PBs in allogeneic HCT with less cGVHD. The biologic mechanism of the lower rate of cGVHD appears to be through mobilization of regulator natural killer cells and plasmacytoid dendritic cell precursors that are associated with lower acute and chronic GVHD compared with G-PBs and rapid engraftment characterized by rapid myeloid-repopulating capacity. We suggest that, based on the experience of the two Phase II clinical trials and the unique biology of plerixafor-mobilized donor product, it should be evaluated in Phase III trials as an approach to replacing G-CSF mobilization for allogeneic HCT.