Thalidomide is an agent with antiangiogenic (angiogenesis - the growth of new blood vessels) and immunomodulatory properties. This new generation of myeloma-fighting drugs interferes with one or more reactions of the cancerous cell and its environs. Thus, the drug inhibits the growth and survival of myeloma cells.
The efficacy of Thalidomide was proven in relapsed and refractory forms of myeloma, especially in combination with dexamethasone. At least five randomised clinical trials are investigating Thalidomide-based induction and maintenance therapy in newly diagnosed patients. The final efficacy assessment is going to be established in5 to 7 years, at the soonest.
However, frequent side effects of the Thalidomide observed in many patients represent an obstacle to a broad use of the drug. According to the foreign investigation centres, Thalidomide is a drug with wide spectrum of side effects that result in discontinuance of the treatment in 30% patients or in a necessary reduction of the dose. The most common side effects include disturbances in consciousness, drowsiness, fatigue, skin changes, obstipation and severe sensomotoric polyneuropathy observed in 30% patients. The most commonly seen hematologic toxicity includes leucopenia. More rarely, patients suffered from trmboembolic disorders (5 - 30%) but in most centres, prophylaxis practice is routinely used. As the Thalidomide sensory neurotoxicity was found to be cumulative dose dependent, the key assignement of the physician is to determine the optimal dosage of the drug.
