Thalidomide Plus Dexamethasone Combination Therapy Shows Promising Results in Treating Multiple Myeloma

Strategic Insights -

The combination of thalidomide plus dexamethasone has been shown to produce a statistically significant improvement in response rates compared to dexamethasone alone in patients with multiple myeloma. According to the final clinical results of a Phase III study presented at the American Society of Hematology 46TH Annual Meeting, 63% of patients treated with thalidomide plus dexamethasone achieved a response, compared to 41% of patients treated with dexamethasone alone (p=0.002).

The study, led by Vincent Rajkumar, M.D., a Mayo Clinic hematologist and oncologist, and coordinated by the Eastern Cooperative Oncology Group (ECOG), enrolled 207 patients with previously untreated symptomatic multiple myeloma. The patients were randomized to receive either thalidomide plus dexamethasone or dexamethasone alone for four cycles, followed by stem cell collection in eligible patients.

The median patient age was 65 years, and the study was designed for both response and toxicity endpoints. The response data confirmed the findings of the interim analysis, with responses occurring in 63% of patients treated with thalidomide plus dexamethasone compared to 41% of patients treated with dexamethasone alone (p=0.002; one-sided Fisher's exact test). When the data were analyzed allowing for use of serum M protein levels alone in patients in whom a measurable urine M protein was unavailable at follow-up, 73% responded to the thalidomide/dexamethasone arm and 50% to the dexamethasone only arm.

Key Takeaways:

  • The combination of thalidomide plus dexamethasone showed a significantly higher response rate (63%) compared to dexamethasone alone (41%) in patients with multiple myeloma.
  • The median patient age was 65 years, and the study was designed for both response and toxicity endpoints.
  • The response data confirmed the findings of the interim analysis, with responses occurring in 63% of patients treated with thalidomide plus dexamethasone.
  • The study enrolled 207 patients with previously untreated symptomatic multiple myeloma.
  • The primary end point of the study was the best response within four months on an intent-to-treat basis.
  • The median time to response was rapid and similar in both arms, at 1.1 months.
  • The study found that thalidomide plus dexamethasone was associated with an increased risk of deep vein thrombosis (DVT) compared to dexamethasone alone.
  • Dr. Rajkumar stated that the study demonstrates a need to balance the higher response rate with thalidomide plus dexamethasone with the greater toxicity.

Statistics:

  • 63% of patients treated with thalidomide plus dexamethasone achieved a response, compared to 41% of patients treated with dexamethasone alone (p=0.002).
  • 73% of patients in the thalidomide/dexamethasone arm responded to treatment, compared to 50% in the dexamethasone only arm.
  • 1.1 months was the median time to response in both treatment arms.

Sources:

  • The clinical data were presented at the American Society of Hematology 46TH Annual Meeting in San Diego, CA from December 3-7, 2004.
  • The study was led by Vincent Rajkumar, M.D., a Mayo Clinic hematologist and oncologist, and coordinated by the Eastern Cooperative Oncology Group (ECOG).
  • The study was funded by Celgene Corporation.
  • The data were presented in a press release by Celgene Corporation on December 7, 2004.