Phase II Studies of TRISENOX in Multiple Myeloma and Myelodysplastic Syndrome Yield Promising Results
Wednesday May 19, 7:02 am ET
Data From Two Studies Recently Published in International Scientific Journals
SEATTLE, May 19 /PRNewswire-FirstCall/ -- A study by A. Raza, M.D. of Rush Medical Center, published in Leukemia Research, concluded that the combination of TRISENOX® (arsenic trioxide) injection and thalidomide in patients with myelodysplastic syndrome (MDS) produced multi-lineage hematologic responses in 25 percent of patients studied. A separate study by M. Hussein, M.D. of the Cleveland Clinic Foundation, published in the British Journal of Haematology, showed that TRISENOX as a mono-therapy resulted in a clinical benefit to patients with relapsed or refractory multiple myeloma with objective responses in 33 percent of patients studied. Cell Therapeutics, Inc. (CTI) (Nasdaq: CTIC; Nuovo Mercato) markets TRISENOX in the U.S. and Europe.
In the MDS study, 28 patients with a confirmed diagnosis of MDS were treated with the combination of TRISENOX and thalidomide. Seven patients responded including one complete hematologic and cytogenetic response. Two trilineage responses were seen in patients with inv(3), a chromosomal abnormality associated with overexpression of a gene called EVI1 that is associated with poor outcome in both MDS and acute myelogenous leukemia. Three of the five patients who had high pre-therapy EVI1 levels showed unexpectedly good responses. Responses were noted in both low- and high-risk MDS, but were particularly striking for the high-risk patients. The combination was generally well tolerated, fluid retention and myelosuppression being the major toxicities observed. All side effects were reversible once the drugs were discontinued.
"Results of this combination study appear to be different than the experience with thalidomide alone as the responses from the combination regimen are more commonly multi-lineage and more high-risk patients appear to be responding," stated Raza. "This study has been followed by an ongoing single-agent study of TRISENOX and thalidomide to determine if TRISENOX is as effective as a single-agent."
In the Hussein multiple myeloma study, 24 multiple myeloma patients, 16 of whom were refractory to previous regimens, were treated with single-agent TRISENOX. Responses, defined as reductions of 25 percent or more in serum M-protein levels, occurred in eight of 24 patients (33 percent). An additional six patients (25 percent) achieved stable disease. The median time to response was 67 days, with a median duration of response lasting 130 days. Therapy was generally well tolerated, with mostly mild to moderate adverse events. Neutropenia was the most commonly reported side effect, however it was not associated with neutropenic fever. Notably, renal function improved during treatment in the two patients with myeloma kidneys.
"The clinical efficacy and favorable toxicity profile of TRISENOX demonstrated in this study argue for the further evaluation of the drug in relapsed or refractory multiple myeloma using new dosing strategies and combining TRISENOX with ascorbic acid as well as with traditional therapeutic agents, such as melphalan and dexamethasone, or with non-traditional agents, such as bortezomid and thalidomide," stated Hussein. |
