Ultra-Low Dose Interleukin-2 for Refractory Chronic Graft Versus Host Disease

Three dose levels were evaluated to determine the maximally tolerated dose (MTD): Dose level A: 0.3 x 10\^6 IU/m\^2/day Dose level B: 1.0 x 10\^6 IU/m\^2/day Dose level C: 3.0 x 10\^6 IU/m\^2/day Once the MTD (dose level B) was established, an additional 10 participants were enrolled at this dose.

Time frame: Participants were assessed for toxicities at mandatory study follow-up visits during the 8 week course of study therapy and four weeks post therapy

Population: One participant terminated therapy early and was not evaluable for this outcome measure.

Changes in the above immune cell populations (CD3+T, CD4+T (including CD4+Treg and CD4+Tcon), CD8+T, NK, NKT and B cell counts were measured at study appointments during the 8-week IL-2 treatment and four weeks post study therapy. All study participants (n=28) with a sample available were reported in the data table. Immune outcome data cannot be meaningfully rendered in the template provided, owing to complexity. The tables below only represent a general overview of the data. Please refer to figure 2 in our published report (Koreth et al, NEJM 2011).

Time frame: Immunological samples taken at study appointments during the 12 week protocol schedule

Population: Participants were evaluated for regulatory T cell (Treg) expansion and other immune-cell changes while on low-dose IL-2 therapy. Participants had blood samples drawn at study appointments during the 12 week protocol schedule. Please note that for NK and NKT cell counts, only 18 participants samples were analyzed.

Feasibility: the number of participants who tolerated at least 6 weeks of therapy, and were thus evaluable for response. Efficacy: chronic GVHD response per NIH consensus criteria in evaluable patients. A complete response was defined as resolution of all reversible chronic GVHD-associated manifestations, a partial response as an improvement of 50% or more on the organ-specific chronic GVHD scale without progression at other organs or sites, progressive disease as an increase of 25% or more on the organ specific chronic GVHD scale, and stable disease as an improvement of less than 50% or increase of less than 25%. Please refer to the Supplementary Appendix in our published report (Koreth et al, NEJM 2011) for further details.

Time frame: Participants were assessed for toxicities at mandatory study follow-up visits during the 8 week course of study therapy and four weeks post therapy. cGVHD was assessed at Weeks 8 and 12

Population: Participants were evaluable for response and considered meeting the feasibility endpoint if they completed at least 6 weeks of treatment. Participants who had a partial response or complete response in cGVHD to treatment were considered to meet the efficacy endpoint.

Changes in the ratio of the CD4+ regulatory T cell (Treg) and CD4+ conventional T cell (Tcon) counts were measured at study appointments during the 8-week IL-2 treatment and four weeks post study therapy. All study participants (n=28) with a sample available were reported in the data table. Immune outcome data cannot be meaningfully rendered in the template provided, owing to complexity. The tables below only represent a general overview of the data. Please refer to figure 2 in our published report (Koreth et al, NEJM 2011).

Time frame: Immunological samples taken at study appointments during the 12 week protocol schedule

Population: Participants were evaluated for changes to the ratio of regulatory T cell (Treg) and conventional T cell (Tcon) counts while on IL-2 therapy. Participants had blood samples drawn at study appointments during the 12 week protocol schedule to analyze the immunological effects of low-dose IL-2 therapy.