Crizotinib improves progression-free survival in advanced ALK-positive lung cancer patients

This phase III trial investigated the benefits of crizotinib (Xalkori) as treatment for ALK-positive lung cancer patients. Patient outcome with crizotinib treatment was compared to that of treatment with standard chemotherapy.

Non-small-cell lung cancer (NSCLC) cells may contain different genetic mutations that cause these cells to divide and spread rapidly, promoting tumor formation. A mutation in the anaplastic lymphoma kinase (ALK) gene is responsible for about 5% of non-small cell lung cancers (NSCLC). These cancers are referred to as ALK-positive NSCLC. Crizotinib is an oral drug that targets and blocks an enzyme produced by these ALK-positive cells. Crizotinib has shown promising results in early phase trials, achieving response to treatment (measured by reduction in tumor size) in up to 70% of ALK-positive NSCLC patients. However, how crizotinib treatment compares to standard chemotherapy is still unknown.

This trial included patients with advanced or metastatic, ALK-positive, NSCLC, that has progressed despite previous chemotherapy treatments. 347 patients were randomly assigned to receive treatment with crizotinib (taken orally) or standard chemotherapy (received intravenously).

Response to treatment and progression-free survival (PFS; the amount of time until the cancer worsens or progresses after treatment) were compared between the two treatment groups. 65% of patients treated with crizotinib showed some response to treatment compared to only 20% of patients who responded to treatment with standard chemotherapy. The average PFS was 7.7 months in the crizotinib treatment group compared to only 3.0 months in the chemotherapy group. However, no significant benefit on overall survival was seen with crizotinib treatment. Crizontinib was also associated with greater reductions in the symptoms of lung cancer and a greater improvement in quality of life (as reported by patients) compared to chemotherapy.

This trial concluded that crizotinib was more beneficial than standard chemotherapy in treating patients with advanced, ALK-positive, non-small-cell lung cancer. Crizotinib not only showed superior response rates compared to chemotherapy, but also improved progression free survival significantly.

It is not yet clear whether the significant tumor responses achieved with crizotinib translate into an improved overall survival.

This study was supported by Pfizer, the manufacturer of crizotinib (Xalkori).

Consult with your physician regarding the benefits and risks of crizotinib in the treatment of ALK-positive lung cancer.