Efficacy and Safety of Imatinib Mesylate in Advanced Gastrointestinal Stromal Tumors
- Study type
- Clinical trial
- Design
- Multicentre, open-label (unblinded) randomised trial
- Sample size
- 147 patients
- Source
- N Engl J Med · 2002
In plain words
Gastrointestinal stromal tumour (GIST) is a type of tumour that does not respond well to ordinary chemotherapy. In this study, people with advanced disease were given the oral drug imatinib, which blocks a protein (KIT) that is important for the growth of these tumours. In more than half of the patients the tumour shrank, and in about another quarter the disease stayed stable. Side effects were usually mild to moderate (such as swelling, diarrhoea and tiredness), but about 5% of patients had bleeding in the gut or inside the abdomen.
Key results
Treatment arms and regimens
Imatinib mesylate orally, 400 mg per day. Other dosing and schedule details in the full text.
Imatinib mesylate orally, 600 mg per day. Other dosing and schedule details in the full text.
Source of the regimen details: Abstract of the paper
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 advanced gastrointestinal stromal tumour (GIST). Based on the abstract's conclusion, the tumours were unresectable or metastatic. Other inclusion criteria are not given in the abstract and are in the full text.
Endpoints
Assessment of antitumour response, and of drug safety and tolerability. Pharmacokinetics were assessed in a subgroup of patients. The abstract does not divide endpoints into primary and secondary.
Safety and side effects
Treatment was well tolerated, although mild to moderate oedema, diarrhoea and fatigue were common. Gastrointestinal or intra-abdominal haemorrhage occurred in about 5% of patients. No significant difference in toxic effects was seen between the two doses. The rate of grade 3 or higher adverse events is not reported in the abstract.
Clinical significance and place in guidelines
This study showed that inhibiting the KIT pathway with imatinib can produce durable objective responses in more than half of patients with advanced unresectable or metastatic GIST. This finding matters for tumours resistant to conventional chemotherapy and established targeted therapy as a promising approach. The two doses of 400 and 600 mg per day did not differ significantly in response or toxicity. The current status of approvals and clinical guideline recommendations should be checked separately, as the abstract does not mention them.
Limitations
According to the abstract, the study was open-label and follow-up after onset of response was short (median 24 weeks), so the median duration of response had not yet been reached. In this report, the study was not designed or reported for a precise comparison of the two doses or of survival. 7 patients (4.8%) could not be evaluated for response for technical reasons.
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.