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9 slides generated from the cancer page, with a quiz from the open benchmark and speaker notes that cite the sources. Arrow keys move between slides; Print gives one slide per page.
Chronic-phase chronic myeloid leukaemia is the disease that imatinib turned from fatal into manageable: a daily pill blocks the BCR::ABL1 protein that drives it. Blood tests track the leukaemia gene to a millionth, newer pills such as asciminib (ASC4FIRST) reach deeper responses faster, and patients with years of undetectable disease can try stopping.
The Philadelphia chromosome, t(9;22), fuses BCR to ABL1 and produces a constitutively active tyrosine kinase; in chronic phase the marrow overproduces mature granulocytes with fewer than 10 percent blasts (WHO) and the disease is symptomless in half of patients, found on a routine blood count. Response is measured by quantitative PCR for BCR::ABL1 on the International Scale, with ELN milestones of 10 percent or less at three months, 1 percent or less at six months and 0.1 percent or less (major molecular response) at twelve months; failure to reach them prompts kinase domain mutation testing and a switch of drug.
IRIS (2003) randomised 1,106 newly diagnosed patients to imatinib or interferon plus cytarabine: complete cytogenetic response at 18 months in 76 percent versus 14 percent, and at ten years 83 percent of imatinib patients were alive, most without progression. Second-generation inhibitors dasatinib (DASISION), nilotinib (ENESTnd) and bosutinib (BFORE) produce faster and deeper responses without a survival advantage, at the cost of pleural effusions, vascular events and liver toxicity respectively. Asciminib, which binds the myristoyl pocket rather than the ATP site, beat investigator-selected inhibitors in ASC4FIRST (2024): major molecular response at 48 weeks in 67.7 percent against 49.0 percent, and 69.3 percent against 40.2 percent for imatinib, with fewer side effects, earning accelerated approval for newly diagnosed disease in October 2024.
| Setting | Approach | Guideline |
|---|---|---|
| Newly diagnosed chronic phase | Imatinib 400 mg daily, a second-generation inhibitor (dasatinib, nilotinib, bosutinib) chosen by comorbidity and treatment goal, or asciminib (ASC4FIRST); PCR at 3, 6 and 12 months against ELN milestones. | not mapped |
| Resistance or intolerance | Switch inhibitor guided by kinase domain mutation testing; ponatinib or asciminib for T315I; radotinib or olverembatinib where approved; allogeneic transplant after failure of two or more inhibitors. | not mapped |
| Sustained deep molecular response | Attempt treatment-free remission after at least three to five years of therapy and two years of MR4 or better, with monthly PCR for six months; restart on loss of major molecular response. | not mapped |