Jedrzejcak, Wieslaw

7517 Background: Thalidomide plus dexamethasone (Thal/Dex) yields superior response rates versus dexamethasone (Dex) but its impact as primary therapy for multiple myeloma (MM) is unknown. Methods: Patients (pts) with previously untreated, symptomatic MM were eligible and were randomized in this double-blind trial to Thal/Dex (Arm A) or placebo plus Dex (Arm B). Pts in Arm A received Thal 50 mg PO daily, escalated to 100 mg on day 15, and to 200 mg from day 1 of cycle 2; Dex 40 mg PO was given on days 1–4, 9–12, and 17–20. Pts in Arm B received placebo instead of Thal, and Dex as in Arm A. Cycles were 28 days long, repeated until progression or undue toxicity. The primary endpoint was time to progression (TTP) defined using EBMT criteria. All analyses were intent to treat. Planned sample size was 218 eligible pts in each arm. Full information for one-sided log rank test with significance level of 0.025 (allowing for 1interim analysis) to have 80% power to detect a 40% improvement in TTP (16.8 mo in Arm A vs. 12 mo in Arm B) would be achieved when 282 pts have progressed. A pre-planned interim analysis of the primary endpoint and safety was performed by an independent Data Monitoring Committee (DMC). P value < 0.0015 at this interim analysis would indicate that Arm A is superior to Arm B based on an alpha-spending function of the O’Brien-Fleming type. The DMC recommended release of results. Results: 470 pts were enrolled: 235 randomized to Thal/Dex and 235 to placebo/Dex. Median follow-up was 25 months. Median age was 65 yrs. TTP was significantly superior with Thal/Dex vs placebo/Dex, median TTP 17.4 months (95% CI: 8.1 months-NE) vs 6.4 months (95% CI: 5.6–7.4 months), respectively, P < 0.000065, crossing the upper boundary for superiority. DVT was higher with Thal/Dex vs placebo/Dex, 15.4% vs 4.3%, respectively. Median survival was not reached in either arm. Conclusions: Thal/Dex is significantly superior to Dex alone as first-line therapy for multiple myeloma. [Table: see text] [Table: see text]

Abstract Purpose: Updated results, including response rate data, from a randomized, double-blind, placebo-controlled study comparing thalidomide plus dexamethasone versus dexamethasone alone as primary therapy for newly diagnosed multiple myeloma (MM). Methods: Patients (pts) with previously untreated, symptomatic MM were eligible. Pts were randomized to Thal/Dex (Arm A) or placebo plus Dex (Arm B). Pts in Arm A received Thal 50 mg PO daily, escalated to 100 mg on day 15, and to 200 mg from day 1 of cycle 2; Dex 40 mg PO was given on days 1–4, 9–12, and 17–20. Pts in Arm B received placebo instead of Thal, and Dex as in Arm A. Each cycles was 28 days long. Treatment was continued until progression or undue toxicity. The primary endpoint was time to progression (TTP) defined using EBMT criteria. All analyses were conducted on an intent to treat basis. An independent data monitoring committee recommended release of results. Results: 470 pts were enrolled: 235 were randomized to Thal/Dex and 235 to placebo/Dex. Median follow up is 18 months. Median age was 65 yrs. The response rate (CR+PR) was significantly higher with Thal/Dex compared to placebo/Dex, 59% vs 42%, respectively, P<0.001. Eighty-two percent of patients have gone off-study. TTP was significantly superior with Thal/Dex vs placebo/Dex, median TTP not reached with Thal/Dex versus 8.1 months (95% CI: 6.5–12.8 months) with placebo/Dex, P<0.001. Major grade 3–4 events are summarized in the Table below. Deep vein thrombosis (DVT) was higher with Thal/Dex vs placebo/Dex, 15.4% vs 4.3%, respectively. Conclusions: Thal/Dex yields superior response rates and TTP compared to Dex alone when used as first-line therapy for multiple myeloma. Major Grade 3–4 adverse events Adverse Event Thal/Dex (n=234) Placebo/Dex (n=232) Venous thromboembolism (Grade >=3) 17.9% 4.3% Cerebral ischemia (Grade >=3) 3.0% 1.3% Myocardial ischemia (Grade >=3) 3.8% 2.2% Neuropathy (Grade >=3) 3.0% 0% Any toxicity (Grade >=4) 30.3% 22.8%