AML (acute myeloid leukemia) patients with relapsed refractory diseases or in poor physical conditions have very limited choices of appropriate treatment regimens, and most alternative options are costly. Here, we reported that an affordable regimen with combined recombinant human interferon-α-1b (IFN-α1b), thalidomide, and recombinant interleukin-2 (IL-2) (the ITI regimen) achieved varying degrees of therapeutic effects in AML patients of various disease status and vulnerabilities. ITI regimen was administrated as follow: a subcutaneous injection of IFN-α1b 60 μg qod, IL-2 1 million unit qod, and 200mg thalidomide tablet orally taken every night before sleep.

Group A Sixty-eight patients who were with relapsed or refractory AML were enrolled, sixty finished at least one course, a response rate (CR+CRi) of 16.7% (10/60) was observed, and, and 7 (11.7%) patients achieved partial remission.(Table 1)

Group B Eighteen patients with morphologically complete remission and consistently positive MRD were enrolled, each patients underwent ITI regimen for 2 months at least. According to the criteria of the WHO risk stratification, 7 were with a favorable risk, 8 were with a intermediate risk, and 3 were with a high risk. Patients with FLT3-ITD mutations were treated with oral sorafenib during early induction and consolidation treatment. These 18 patients received conventional dosage of ITI regimen. Seven patients had a negative MRD after 1 or 2 months. The MRD levels of 3 patients significantly decreased after one or two months. Five patients suffered a Morphological relapse. Another 3 patients failed to the conventional dosage of ITI regimen with an increased MRD rate, but it decreased after we made a modification of IFN-α1b and IL-2 administration daily. The response rate of the 18 patients in Group B was 72.2%, where MRD < 0.01% was defined as the negative threshold. (Table 2)

Group C Eighty-eight patients with MRD-negative AML after consolidation were enrolled. Among the 88 patients with initial CR, 11 (12.5%) relapsed during the maintenance period (Figure 1). All these 11 patients relapsed within 2 years, with a median recurrence period of 20 months, of which 2, 4, and 5 patients, respectively, were with favorable, intermediate, and high risk. The indicated that this regimen effectively reduced the relapse rate.(Table 3)

Disclosures

No relevant conflicts of interest to declare.

Author notes

*

Asterisk with author names denotes non-ASH members.