An evaluation of factors predicting long-term response to thalidomide in 234 patients with relapsed or resistant multiple myeloma

The aim of this study was to assess the prognostic value of pretreatment clinical and laboratory parameters in refractory or relapsed multiple myeloma (MM) patients who have a long-term response to thalidomide (THAL), lasting at least 18 months. The study was carried out on 234 patients who received THAL for relapsed/refractory myeloma. Out of the 234 patients, 129 patients (55.1%) responded to THAL with a mean response duration of 11.9 months (ranging from 1 to 48) and an overall survival rate of 20.3 months (ranging 1–55 months). In 64 patients (27.4% of the whole group), the response to THAL lasted ⩾18 months with a mean response lasting 24 months. Statistical analysis of the group of nonresponders and patients with long-term response to THAL showed a significantly higher serum albumin level (P=0.0003) and haemoglobin level (P=0.05), as well as a lower β2 microglobulin (β2M) (P=0.022), LDH (P=0.045) serum level in patients with long-term response. In this study, the LDH and serum albumin level were predictors for response to THAL therapy. The β2M serum level was not a predictor for response to THAL. The albumin serum level was the best parameter distinguishing the group of patients with long-term response to THAL from the entire responding group (P=0.02).

Thalidomide treatment of resistant or relapsed multiple myeloma patients

BACKGROUND AND OBJECTIVES

Thalidomide is currently used as a very promising drug in patients with recurrent multiple myeloma or those refractory to chemotherapy. Literature data show prolonged survival in patients with advanced multiple myeloma treated with thalidomide but the optimal time and dose of thalidomide treatment remain to be established.

DESIGN AND METHODS

We have treated 53 refractory or relapsed myeloma patients with thalidomide (Grunenthal, Aachen). The patients received thalidomide orally as monotherapy at a starting dose of 200 mg daily, with a dose increase of 100 mg every week to a maximum well-tolerated dose of 400 mg. All the patients qualified for the therapy underwent clinical and laboratory assessments every 4 weeks. Laboratory tests included complete blood count, electrophoresis, immunoglobulin level, lactate dehydrogenase (LDH), C-reactive protein, b2 microglobulin concentration, liver and renal function tests and there was also a monthly neurological examination. Bone marrow aspiration was performed every 3 months during the 12-month treatment.

RESULTS

Among 53 evaluable patients, a clinical response was observed in 27 (51%): there was a major response in 7 patients, a partial response in 12 and a minor response in 8.

INTERPRETATION AND CONCLUSIONS

In responding patients the earliest response was observed after 4 weeks of treatment and the latest after 12 weeks of treatment. Our results, obtained during a long observation period, show that thalidomide is an effective drug, with an acceptable degree of toxicity, in patients with refractory multiple myeloma.