Final Data Analysis for Omacetaxine in Chronic, Accelerated Phase Chronic Myeloid Leukemia

the Cancer Therapy Advisor take:

Patients with chronic phase or accelerated phase chronic myeloid leukemia that is resistant and/or intolerant to two or more tyrosine kinase inhibitors can currently receive omacetaxine, a protein synthesis inhibitor.

The final analysis of omacetaxine, which included 24 months of follow-up, revealed additional safety and efficacy information to demonstrate the benefit of long-term omacetaxine administration in patients with chronic phase or accelerated phase chronic myeloid leukemia who received more than 3 cycles of treatment (1.25 mg/m2 twice daily for 14 days every 28 days followed by 7 days every 28 days).

The data showed that 18% of patients with chronic phase chronic myeloid leukemia achieved a major cytogenetic response that lasted a median of 12.5 months. The responses lasted for 12 months or more in three of 14 responders, and the rate of overall survival was a media of 40.3 months (95% CI, 23.8 months to NR). In patients with accelerated phase chronic myeloid leukemia, 14% of patients had a major hematologic response for a median of 4.7 months (95% CI, 3.6 months to NR).

In patients with accelerated phase chronic myeloid leukemia a major cytogenetic response was not seen and there was a median overall survival of 14.3 months (95% CI, 6.7, 18.7 months). There were 50 patients with chronic phase chronic myeloid leukemia who received more than 3 cycles of treatment and 14 patients with accelerated phase chronic myeloid leukemia who received more than 3 cycles of treatment. The median overall survival in these groups were 49.3 months (95% CI, 23.8 months to not reached) and 24.6 months (95% CI, 12, 37.2 months), respectively.

The most prominent side effects were grade 3 or higher hematologic toxicities (79% and 73% for chronic phase chronic myeloid leukemia and accelerated phase chronic myeloid leukemia, respectively). Ten percent of patients with chronic phase disease discontinued treatment because of toxicity and 5% of accelerated phase patients discontinued treatment because of toxicity.