PHILADELPHIAEarly reports of the efficacy of thalidomide(Drug information on thalidomide) (Thalomid) as initial therapy for multiple myeloma have been confirmed by researchers at The University of Texas M.D. Anderson Cancer Center, Donna Weber, MD, reported at a symposium sponsored by the University of Pennsylvania and the Multiple Myeloma Research Foundation.
As sole therapy, thalidomide brought about partial remissions in one third of patients with asymptomatic, previously untreated multiple myeloma at high risk of progression. A combined thalidomide/dexamethasone regimen resulted in responses in more than 70% of patients with symptomatic, previously untreated multiple myeloma, including some complete remissions. These M.D. Anderson results are virtually identical to those previously reported by researchers at the Mayo Clinic.
Remissions produced by either single-agent or combined regimens have been long lasting, and the regimens have the additional advantage of not interfering with subsequent stem cell collection, said Dr. Weber, assistant professor, Department of Lymphoma and Myeloma.
Although final conclusions must await completion of a randomized, controlled trial, combined thalidomide/dexamethasone appears to be among the most active regimens in previously untreated multiple myeloma, she said. Its efficacy approaches that of VAD (vincristine/Adriamycin/dexamethasone) chemotherapy regimens, whose delivery requires an indwelling catheter.
"I feel this oral regimen [thalidomide/dexamethasone] may well be the treatment of choice for previously untreated patients with symptomatic multiple myeloma," Dr. Weber said. A controlled trial of thalidomide/dexamethasone is currently being conducted by the Eastern Collaborative Oncology Group (ECOG).
Researchers studying thalidomide in untreated multiple myeloma have applied many lessons learned in previous studies in refractory disease. In these patients, research from multiple centers has shown fairly uniform response rates of about one third for thalidomide regimens and 40% to 50% for thalidomide/dexamethasone (with response defined as a 50% or greater reduction in serum monoclonal paraprotein, a disease marker).