Daily IL-2 for Steroid-Refractory Chronic Graft-versus-Host-Disease

Participants were evaluated according to the cGVHD NIH Consensus criteria at baseline, 6 weeks, and 12 weeks on study. Per cGVHD NIH Consensus criteria, cGVHD involved organ systems are given a grade 0-3 and an overall cGVHD score, from 0-10, is given. Complete Response is defined as resolution of all reversible manifestations in each organ or site of cGVHD. A partial response is defined as an improvement in measure at least one organ or site, or decrease in global ratings by at least a 2-point change on the 10-point scale, without progression measured at any other organ or site. Non-responders have no change in cGVHD meeting criteria for either partial response or disease progression. Progressive disease is defined as an increase in organ or site scales (1-point change on a 3-point scale) or 2- to 3-point increase on the global cGVHD ratings. Clinical worsening of cGVHD is not synonymous with progressive cGVHD per NIH criteria.

Time frame: Baseline, 6 weeks, and 12 weeks

Population: 33 of 35 patients were evaluable for response criteria. To be evaluable, patients had to receive at least 6 weeks of daily IL-2 and had their disease re-assessed.

Blood samples were collected throughout the patient's 12 weeks of IL-2 treatment and after the 4 week hiatus. The CD4+CD25+FOXP3+ regulatory T cells (Treg) counts were measured.

Time frame: 16 weeks of study follow-up

Blood samples were collected throughout the patient's 12 weeks of IL-2 treatment and after the 4 week hiatus. The ratio between CD4+CD25+FOXP3+ regulatory T cells (Treg) and CD4 conventional T cell (Tcon) counts were measured.

Time frame: 16 weeks of study follow-up

Overall survival (OS) and progression-free survival (PFS) were calculated using the Kaplan-Meier method. OS was defined as from the study entry to death from any cause. Patients who were alive or lost to follow-up were censored at the time last seen alive. PFS was defined from the study entry to disease relapse or progression or death from any cause, whichever occurred first.

Time frame: 2 years from start of IL-2

Participants had their steroid dose assessed at weeks 6, 12,16, and every 8 weeks while on extended duration IL-2 therapy.

Time frame: End of treatment after 16 weeks or most recent follow-up date for patients on extended

Population: Participant's steroid taper was measured using their steroid dose at the start of therapy and their dose at the end of 16 weeks. For participants who continued on extended duration therapy, their final steroid dose was determined at the time of stopping treatment or, if still ongoing, the last clinic visit at the time of data analysis.

Participants were evaluated at clinical visits for toxicities related to IL-2 throughout their 12-week treatment course

Time frame: 12 weeks

Population: Grade 2 or higher, related to IL-2, adverse events (AE) were recorded for participants during their 12-week IL-2 treatment course. AE's were evaluated based on the CTCAE version 4.0.