This consensus document is intended to serve 3 functions. First, it standardizes the criteria for diagnosis of chronic graft-versus-host disease (GVHD). Second, it proposes a new clinical scoring system (0-3) that describes the extent and severity of chronic GVHD for each organ or site at any given time, taking functional impact into account. Third, it proposes new guidelines for global assessment of chronic GVHD severity that are based on the number of organs or sites involved and the degree of involvement in affected organs (mild, moderate, or severe). Diagnosis of chronic GVHD requires the presence of at least 1 diagnostic clinical sign of chronic GVHD (e.g., poikiloderma or esophageal web) or the presence of at least 1 distinctive manifestation (e.g., keratoconjunctivitis sicca) confirmed by pertinent biopsy or other relevant tests (e.g., Schirmer test) in the same or another organ. Furthermore, other possible diagnoses for clinical symptoms must be excluded. No time limit is set for the diagnosis of chronic GVHD. The Working Group recognized 2 main categories of GVHD, each with 2 subcategories. The acute GVHD category is defined in the absence of diagnostic or distinctive features of chronic GVHD and includes (1) classic acute GVHD occurring within 100 days after transplantation and (2) persistent, recurrent, or late acute GVHD (features of acute GVHD occurring beyond 100 days, often during withdrawal of immune suppression). The broad category of chronic GVHD includes (1) classic chronic GVHD (without features or characteristics of acute GVHD) and (2) an overlap syndrome in which diagnostic or distinctive features of chronic GVHD and acute GVHD appear together. It is currently recommended that systemic therapy be considered for patients who meet criteria for chronic GVHD of moderate to severe global severity.

The 2005 National Institutes of Health (NIH) Consensus Conference proposed new criteria for diagnosing and scoring the severity of chronic GVHD. The 2014 NIH consensus maintains the framework of the prior consensus with further refinement based on new evidence. Revisions have been made to address areas of controversy or confusion, such as the overlap chronic GVHD subcategory and the distinction between active disease and past tissue damage. Diagnostic criteria for involvement of mouth, eyes, genitalia, and lungs have been revised. Categories of chronic GVHD should be defined in ways that indicate prognosis, guide treatment, and define eligibility for clinical trials. Revisions have been made to focus attention on the causes of organ-specific abnormalities. Attribution of organ-specific abnormalities to chronic GVHD has been addressed. This paradigm shift provides greater specificity, more accurately measures the global burden of disease attributed to GVHD, and will facilitate biomarker association studies.

Background Dysfunction of regulatory T (Treg) cells has been detected in diverse inflammatory disorders, including chronic graft-versus-host disease (GVHD). Interleukin-2 is critical for Treg cell growth, survival, and activity. We hypothesized that low-dose interleukin-2 could preferentially enhance Treg cells in vivo and suppress clinical manifestations of chronic GVHD. Methods In this observational cohort study, patients with chronic GVHD that was refractory to glucocorticoid therapy received daily low-dose subcutaneous interleukin-2 (0.3×106, 1×106, or 3×106 IU per square meter of body-surface area) for 8 weeks. The end points were safety and clinical and immunologic response. After a 4-week hiatus, patients with a response could receive interleukin-2 for an extended period. Results A total of 29 patients were enrolled. None had progression of chronic GVHD or relapse of a hematologic cancer. The maximum tolerated dose of interleukin-2 was 1×106 IU per square meter. The highest dose level induced unacceptable constitutional symptoms. Of the 23 patients who could be evaluated for response, 12 had major responses involving multiple sites. The numbers of CD4+ Treg cells were preferentially increased in all patients, with a peak median value, at 4 weeks, that was more than eight times the baseline value (P<0.001), without affecting CD4+ conventional T (Tcon) cells. The Treg:Tcon ratio increased to a median of more than five times the baseline value (P<0.001). The Treg cell count and Treg:Tcon ratio remained elevated at 8 weeks (P<0.001 for both comparisons with baseline values), then declined when the patients were not receiving interleukin-2. The increased numbers of Treg cells expressed the transcription factor forkhead box P3 (FOXP3) and could inhibit autologous Tcon cells. Immunologic and clinical responses were sustained in patients who received interleukin-2 for an extended period, permitting the glucocorticoid dose to be tapered by a mean of 60% (range, 25 to 100). Conclusions Daily low-dose interleukin-2 was safely administered in patients with active chronic GVHD that was refractory to glucocorticoid therapy. Administration was associated with preferential, sustained Treg cell expansion in vivo and amelioration of the manifestations of chronic GVHD in a substantial proportion of patients. (Funded by a Dana–Farber Dunkin' Donuts Rising Star award and others; ClinicalTrials.gov number, NCT00529035.)

B cells may be implicated in the pathophysiology of chronic graft-versus-host disease (GVHD), as evidenced by antibody production against sex-mismatched, Y chromosome-encoded minor HLA antigens in association with chronic GVHD. We therefore designed a phase 1/2 study of anti-B-cell therapy with rituximab in steroid-refractory chronic GVHD. Twentyone patients were treated with 38 cycles of rituximab. Rituximab was tolerated well, and toxicity was limited to infectious events. The clinical response rate was 70%, including 2 patients with complete responses. Responses were limited to patients with cutaneous and musculoskeletal manifestations of chronic GVHD and were durable through 1 year after therapy. The median dose of prednisone among treated subjects fell from 40 mg/day to 10 mg/day, 1 year after rituximab therapy (P < .001). A chronic GVHD symptom score improved in the majority of treated patients. Antibody titers against Y chromosome-encoded minor HLA antigens fell and remained low, whereas titers against infectious antigens (EBV, tetanus) remained stable or rose during the treatment period. We conclude that specific anti-B-cell therapy with rituximab may be beneficial for patients with steroidrefractory chronic GVHD. This trial was registered at www.clinicaltrials.gov as #NCT00136396. (Blood. 2006;108:756-762)