July 2022: Crizotinib (Xalkori, Pfizer Inc.) was granted approval by the Food and Drug Administration (FDA) for the treatment of adult and paediatric patients 1 year of age and older who were diagnosed with unresectable, recurrent, or refractory inflammatory anaplastic lymphoma kinase (ALK)-positive myofibroblastic tumours that were positive for ALK (IMT).
Both the safety and efficacy of crizotinib were evaluated in two separate multicenter, single-arm, open-label trials. These trials included both paediatric and adult patients with unresectable, recurrent, or refractory ALK-positive IMT. The paediatric patients participated in trial ADVL0912 (NCT00939770), while the adult patients participated in trial A8081013 (NCT01121588).
The objective response rate was the primary indicator of efficacy that was measured in these trials (ORR). An objective response was found in 12 out of the 14 paediatric patients (which corresponds to an 86% success rate with a 95% confidence interval ranging from 57% to 98%) when the patients were evaluated by an independent review committee. Five out of the seven adult patients exhibited objective signs of improvement.
The symptoms of vomiting, nausea, diarrhoea, abdominal pain, rash, vision disorder, upper respiratory tract infection, cough, pyrexia, musculoskeletal pain, fatigue, edoema, and constipation were the most common adverse reactions (35 percent) in paediatric patients. In adult patients, vision disorders, nausea, and edoema were the adverse reactions that occurred more frequently than thirty-five percent of the time.
Crizotinib should be administered orally twice daily at a dose of 250 milligrammes (mg) in adult patients until the disease worsens or unacceptable toxicity is reached. Orally administering 280 mg/m2 twice daily is the paediatric dose that is recommended until disease progression or unacceptable toxicity occurs.
