According to results recently presented at the 2005 annual meeting of the American Society of Clinical Oncology, treatment with the drug Velcade (bortezomib) may overcome the poor prognosis of multiple myeloma that is characterized by a genetic mutation.
Multiple myeloma is a cancer of the blood that affects the plasma cells. Plasma cells are an important part of the immune system and produce antibodies to help fight infection and disease. Multiple myeloma is characterized by an excess production of abnormal plasma cells, which can result in symptoms such as increased risk for bacterial infections or impaired immune responses. Other effects of myeloma may include damage to the kidneys, osteoporosis, anemia and an elevated blood calcium level. Although Multiple myeloma is not curable, it can be treated, thereby allowing patients to live longer, healthier lives. Treatment options for multiple myeloma include watchful waiting, chemotherapy, radiation, and in some cases, stem cell transplantation. Velcade is a newer type of chemotherapy known as proteasome inhibitor and works by disrupting cellular processes causing cell death.
In some cases of multiple myeloma, evaluation of the cells may reveal that a genetic abnormality may exist, which is considered to indicate a poor prognosis. However, previous research has demonstrated that patients treated with Velcade had similar response rates and survival rates despite the presence of the abnormal gene. Researchers were led to believe that Velcade may overcome the negative effects associated with the abnormal gene in multiple myeloma, and this study was conducted to confirm these findings.
Initially, researchers enrolled 669 patients with relapsed multiple myeloma in this recent multi-center study, known as the APEX trial. In this trial, patients were treated with either Velcade or the drug dexamethasone. Overall results indicated that when compared to the patients treated with dexamethasone, patients had an improvement in survival after receiving treatment with Velcade. Researchers then performed genetic analysis on 168 of these patients and 14% were found to have genetic abnormalities. Further analysis revealed that the patients with the genetic abnormalities who had initially been treated with dexamethasone had a significantly reduced survival when compared to the patients with intact genes that were treated with dexamethasone. However, patients with the genetic abnormality who were treated with Velcade did not have a significant difference in survival when compared to the patients with intact genes. Additionally, the response rate was similar between the two groups.
Researchers concluded that Velcade appears to overcome the negative prognosis associated with genetic abnormalities associated with multiple myeloma. Velcade may become an important treatment option for patients diagnosed with genetic abnormalities associated with multiple myeloma.
Reference: Jagannath S, Richardson P, Sonneveld P, et al. Bortezemid appears to overcome poor prognosis conferred by chromosome 13 deletion in phase 2 and 3 trials. Proceedings from the 2005 annual meeting of the annual American Society of Clinical Oncology. Abstract #6501.