Usefulness Of Low-Dose Thalidomide For Japanese Patients With Refractory And Relapsed Multiple Myeloma

18543 Background: Thalidomide is not licensed in Japan, and many patients with multiple myeloma (MM) are therefore taking thalidomide that is imported from other countries. In this study, the effectiveness and side effects of thalidomide in patients with MM who took the drug from 2003 to November 2006 were retrospectively analyzed. Methods: Forty-one patients with refractory and relapsed MM were treated with thalidomide. The median age of the patients was 67.6 years (range,48 to 90 years) Most patients (88%) were treated at a dose of 100 mg/day, but the dose was later modified due to toxities, responses and monetary matters. Thalidomide was administered alone (n=21) and in combination with other drugs (n=20) such as dexamethasone. Results: Seventeen patients (41%) responded to thalidomide (nine patients (22%) showed a reduction in myeloma protein of over 50% and eight patients (19%)showed a reduction of 25–50%.). Kaplan-Meier estimates of overall survival were 68.6% at 1 year and 38.4% at 2 years.The 2-year overall survival rate was higher in ten patients who underwent autologous stem cell transplantation(P<0.001). Low-dose thalidomide was tolerated well but thalidomide treatment had to be discontinued in two patients because of life-threatening interstitial pneumonitis (Onozawa et al. JCO 2005,23). Conclusions: Low-dose thalidomide is useful for treatment of advanced myeloma and can improve prognosis. However, thalidomide, even when administered at a low dose, can caese life-threatening toxicities, and attention must therefore be given to safe use of the drug. No significant financial relationships to disclose.