CytRx announced results from its ENABLE Phase 2 trial that demonstrated bafetinib, the company’s Bcr-Abl, Lyn and Fyn kinase inhibitor, was clinically active in a group of patients with relapsed B-cell chronic lymphocytic leukemia (B-CLL) who have failed several other treatments for their cancer.
Based on the indication of clinical activity and the low incidence of adverse events, additional patients enrolled in the ENABLE Phase 2 clinical trial will receive bafetinib as a single agent at a higher dose.
The ENABLE Phase 2 clinical trial, which is expected to enroll a total of 30 patients, is being performed at M.D. Anderson Cancer Center, City of Hope Medical Center and Cancer Care Centers. Patients self-administer bafetinib twice daily every day and continue treatment as long as their cancer is controlled and no intolerable side effects occur. The trial’s objectives are to assess preliminary efficacy of administration of bafetinib in B-CLL patients and evaluate its safety in this patient population.
“Due to the low incidence of adverse events, we are now able to increase the dose of bafetinib administered to newly enrolled patients, thus increasing the potential for greater efficacy,” says CytRx president and chief executive officer, Steven A. Kriegsman.
Of the 16 patients enrolled in the clinical trial, 11 patients were evaluable for tumor response (patients who have received both baseline and follow-up tumor assessments). At the time of evaluation, the median duration of treatment for all patients was two months, and five of these 11 patients had received three to five months of bafetinib therapy; five patients either did not receive baseline or follow-up assessments. The median number of prior therapies for the full group is three, with a range between one and five prior therapies, and nine of 12 patients demonstrated unfavorable cytogenetics.
All 11 evaluable patients demonstrated elevation in their lymphocyte counts during the first two months of treatment, similar to other kinase inhibitors being tested in B-CLL patients. Six demonstrated shrinkage in their lymph nodes and/or spleen, two patients had stable disease and three patients had progressive disease at their initial assessments. Lymph node softening also was noted in these patients.
“These results are very encouraging,” says Daniel Levitt, MD, PhD, chief medical officer at CytRx. “Lyn kinase, a primary target of bafetinib, is important to the activation and growth of B cells. It is upstream from both PI3kinase delta and Bruton’s tyrosine kinase in B-CLL and may regulate the activity of these other kinases in B cell malignancies.”
Release Date: June 13, 2011
Source: CytRx Corporation
Filed Under: Drug Discovery