Chronic graft-versus-host disease (GVHD) remains a common and potentially life-threatening complication of allogeneic hematopoietic stem cell transplantation (HCT). The 2-year cumulative incidence of chronic GVHD requiring systemic treatment is ∼30% to 40% by National Institutes of Health criteria. The risk of chronic GVHD is higher and the duration of treatment is longer after HCT with mobilized blood cells than with marrow cells. Clinical manifestations can impair activities of daily living and often linger for years. Hematology and oncology specialists who refer patients to centers for HCT are often subsequently involved in the management of chronic GVHD when patients return to their care after HCT. Treatment of these patients can be optimized under shared care arrangements that enable referring physicians to manage long-term administration of immunosuppressive medications and supportive care with guidance from transplant center experts. Keys to successful collaborative management include early recognition in making the diagnosis of chronic GVHD, comprehensive evaluation at the onset and periodically during the course of the disease, prompt institution of systemic and topical treatment, appropriate monitoring of the response, calibration of treatment intensity over time in order to avoid overtreatment or undertreatment, and the use of supportive care to prevent complications and disability.

Key Points: Before GVHD treatment, informative plasma biomarkers included TIM3, IL6, sTNFR1 (for grade 3-4 GVHD), and ST2 and sTNFR1 (for NRM at 1 year). In a day 14 landmark analysis, plasma TIM3 was predictive of grade 3-4 GVHD.

Key Points: Variable mismatching for minor histocompatibility antigens correlates with the risk of severe GVHD after HCT with sibling donors. HLA-mismatching likely explains most of the increased risk of GVHD after HCT with unrelated donors.

Treatment of chronic graft-versus-host disease is intended to produce a sustainable benefit by reducing symptom burden, controlling objective manifestations of disease activity, preventing damage and impairment, and improving overall survival without causing disproportionate harms related to the treatment itself. Successful management can control the disease until systemic treatment is no longer needed. The complexity of the disease, the extended duration of follow-up needed to observe disease resolution and withdrawal of immunosuppressive treatment, and the lack of fully developed shorter term endpoints impede progress in the field. Identification and characterization of primary endpoints demonstrating clinical benefit without requiring years of follow-up is urgently needed, with the understanding that clinical benefit encompasses not only the self-evident benefit of the primary endpoint but also any other associated benefits. This report discusses regulatory considerations, eligibility criteria, the value of controlled trial designs, the merits of proposed primary endpoints, and key considerations elaborated from experience and progress during the past decade. The report concludes by mapping an overall approach that could support and lead to maximally informative clinical trials, especially those that seek to demonstrate clinical benefit along a pathway to regulatory review and approval.

PURPOSE: Graft-versus-host disease (GVHD) causes morbidity and mortality following allogeneic hematopoietic cell transplantation. Naive T cells (T_N) cause severe GVHD in murine models. We evaluated chronic GVHD (cGVHD) and other outcomes in three phase II clinical trials of T_N-depletion of peripheral blood stem-cell (PBSC) grafts. METHODS: One hundred thirty-eight patients with acute leukemia received T_N-depleted PBSC from HLA-matched related or unrelated donors following conditioning with high- or intermediate-dose total-body irradiation and chemotherapy. GVHD prophylaxis was with tacrolimus, with or without methotrexate or mycophenolate mofetil. Subjects received CD34-selected PBSC and a defined dose of memory T cells depleted of T_N. Median follow-up was 4 years. The primary outcome of the analysis of cumulative data from the three trials was cGVHD. RESULTS: cGVHD was very infrequent and mild (3-year cumulative incidence total, 7% [95% CI, 2 to 11]; moderate, 1% [95% CI, 0 to 2]; severe, 0%). Grade III and IV acute GVHD (aGVHD) occurred in 4% (95% CI, 1 to 8) and 0%, respectively. The cumulative incidence of grade II aGVHD, which was mostly stage 1 upper gastrointestinal GVHD, was 71% (95% CI, 64 to 79). Recipients of matched related donor and matched unrelated donor grafts had similar rates of grade III aGVHD (5% [95% CI, 0 to 9] and 4% [95% CI, 0 to 9]) and cGVHD (7% [95% CI, 2 to 13] and 6% [95% CI, 0 to 12]). Overall survival, cGVHD-free, relapse-free survival, relapse, and nonrelapse mortality were, respectively, 77% (95% CI, 71 to 85), 68% (95% CI, 61 to 76), 23% (95% CI, 16 to 30), and 8% (95% CI, 3 to 13) at 3 years. CONCLUSION: Depletion of T_N from PBSC allografts results in very low incidences of severe acute and any cGVHD, without apparent excess risks of relapse or nonrelapse mortality, distinguishing this novel graft engineering strategy from other hematopoietic cell transplantation approaches.

Key Points: Failure-free survival is a potentially useful, efficient, and robust basis for interpreting results of initial treatment of chronic GVHD.