Imatinib Compared with Interferon and Low-Dose Cytarabine for Newly Diagnosed Chronic-Phase Chronic Myeloid Leukemia
- Study type
- Clinical trial
- Study name
- IRIS
- Phase
- Phase 3
- Design
- Randomised trial controlled with an active comparator, with crossover to the other group allowed in case of treatment failure or intolerance
- Sample size
- 1106 patients
- Source
- N Engl J Med · 2003
In plain words
In this large study, the drug imatinib (which acts in a targeted way on the abnormal protein that drives chronic myeloid leukaemia) was compared with an older treatment, interferon plus low-dose cytarabine. In most patients, imatinib reduced or cleared the cells carrying the abnormal Philadelphia chromosome, less often led to the disease moving on to more advanced stages, and was better tolerated.
Key results
Treatment arms and regimens
Imatinib 400 mg orally daily (553 patients).
Interferon alfa 5 million IU/m² subcutaneously daily + cytarabine 20 mg/m² subcutaneously daily for 10 days each month (553 patients). Crossover was allowed for lack of response (no complete haematological response by 6 months or no major cytogenetic response by 12 months), progression, loss of response or intolerance.
Source of the regimen details: Full text of the IRIS ten-year follow-up report (NEJM 2017) in PMC (PMC5901965), Methods section
Doses are given for the information of specialists, as in this study’s protocol, and are not a prescription. Every drug must be prescribed by the treating physician for the individual patient.
Study population
Patients with newly diagnosed Philadelphia chromosome-positive CML in chronic phase.
Endpoints
Haematological and cytogenetic responses, toxic effects and rates of disease progression were assessed. According to the abstract, the main results included major cytogenetic response, complete cytogenetic response and freedom from progression to accelerated phase or blast crisis at 18 months.
Safety and side effects
According to the abstract, imatinib was better tolerated than the combination therapy. Specific rates of grade ≥3 adverse events are not stated in the abstract.
Clinical significance and place in guidelines
This study showed that imatinib is superior to interferon alfa plus low-dose cytarabine as first-line treatment for newly diagnosed chronic-phase CML in terms of response, tolerability and prevention of disease progression. Its current status in clinical guidelines and drug approvals should be checked separately.
Limitations
The abstract reports only a median follow-up of 19 months, so long-term survival data and the durability of response are not available in this abstract. Crossover of patients to the other group was also allowed. Dose details and exact adverse event rates are not given in the abstract.
This summary was prepared by the editorial team from the published paper; the original paper is the final reference. Read the original abstract on PubMed.