Low-Dose Thalidomide for Multiple Myeloma: Interim Analysis of a Compassionate Use Program

Chemotherapy-induced peripheral neurotoxicity: a critical analysis

With a 3-fold increase in the number of cancer survivors noted since the 1970s, there are now over 28 million cancer survivors worldwide. Accordingly, there is a heightened awareness of long-term toxicities and the impact on quality of life following treatment in cancer survivors. This review will address the increasing importance and challenge of chemotherapy-induced neurotoxicity, with a focus on neuropathy associated with the treatment of breast cancer, colorectal cancer, testicular cancer, and hematological cancers. An overview of the diagnosis, symptomatology, and pathophysiology of chemotherapy-induced peripheral neuropathy will be provided, with a critical analysis of assessment strategies, neuroprotective approaches, and potential treatments. The review will concentrate on neuropathy associated with taxanes, platinum compounds, vinca alkaloids, thalidomide, and bortezomib, providing clinical information specific to these chemotherapies.

A combination of melphalan, prednisone, and 50 mg thalidomide treatment in non-transplant-candidate patients with newly diagnosed multiple myeloma

BACKGROUND/AIMS

The clinical efficacy and safety of a three-drug combination of melphalan, prednisone, and thalidomide were assessed in patients with multiple myeloma who were not candidates for high-dose therapy as a first-line treatment. Because the side effects of thalidomide at a dose of ≥ 100 mg daily can be a barrier to effective treatment for these patients, we evaluated the efficacy and safety of a reduced dose of thalidomide, 50 mg, for non-transplant candidates.

METHODS

Twenty-one patients were treated in 4-week cycles, receiving 4 mg/m(2) melphalan and 40 mg/m(2) prednisone on days 1-7 and 50 mg thalidomide daily. The primary efficacy outcome was the overall response rate. Aspirin (100 mg daily) was also provided as prophylactic treatment for thromboembolism.

RESULTS

The overall response rate was 57.1%; a complete response was seen in 23.8% of patients, a partial response in 33.3%, and stable disease in 9.5%. After a median follow-up time of 16.1 months, the median time to progression was 11.4 months (95% confidence interval, 2.1 to 20.6); the median overall survival was not reached. Grades 3 and 4 adverse events included infection (10%), peripheral neuropathy (5%), diarrhea (5%), thrombosis (10%), and loss of consciousness (10%). Two patients discontinued treatment due to loss of consciousness and neuropathy.

CONCLUSIONS

Low-dose thalidomide (50 mg) plus melphalan and prednisone is an effective combination drug therapy option for newly diagnosed myeloma patients who are ineligible for high-dose chemotherapy.

Complete Remission and Early Relapse of Refractory Plasma Cell Leukemia after Bortezomib Induction and Consolidation by HLA-Mismatched Unrelated Allogeneic Stem Cell Transplantation

BACKGROUND

Chromosomal deletion of q13 (del q13) and plasma cell leukemia predict both a worse prognosis in myeloma. Experiences with bortezomib in plasma cell leukemia prior to allogeneic stem cell transplantation (SCT) have not yet been reported.

CASE REPORT

A 66- year-old male patient was admitted for IgA myeloma(IIIA) with del q13. The myeloma progressed to plasma cell leukemia. Bortezomib was given, free light chain (FLC) excretion decreased, and myeloma cells disappeared from blood and decreased in marrow. An unrelated, mismatched allogeneic SCT was performed. The patient was discharged after engraftment with full chimerism without signs of GvHD. FLC excretion increased, and immunosuppression was discontinued. From day +84 on, bortezomib was infused again and FLC excretion decreased rapidly. Relapse was confirmed in marrow, and bortezomib was continued. Donor lymphocyte infusions (DLI) had no effect, and a further cycle of bortezomib and thalidomide had only minor effects. On day +209, the patient died from myeloma.

CONCLUSION

This case gives evidence for an excellent initial response of plasma cell leukemia to bortezomib, however, early relapse after SCT clearly indicates limitations of both bortezomib therapy and allogeneic SCT in high-risk myeloma. Future developments are mandatory and could include combination of bortezomib with other cytostatics and early DLI in the absence of GvHD. In addition, there is need to clarify if graft-versus-myeloma effect is diminished by bortezomib therapy after allogeneic SCT.

Neurologic toxicities of cancer therapies

Neurologic dysfunction is a well-recognized adverse effect of cancer therapeutics. The most common manifestations include peripheral neuropathy and encephalopathy. Often, symptoms resolve or improve upon removal of the offending agent; therefore, it is essential that clinicians recognize the symptoms and signs of injury. Occasionally, symptoms persist or develop after discontinuation of medication and may culminate in disability and diminished quality of life. As our understanding of neurotoxicity improves, medications with less potential for injury may be developed. In addition, potential antidotes to prevent or reverse injury may emerge. This review focuses on the clinical features, mechanisms, and possible therapeutics of the neurotoxicity of chemotherapy. In particular, oxaliplatin, thalidomide, methotrexate, ifosfamide, cytarabine, amifostine, acetyl-L-carnitine, methylene blue, cytokines, and neurotrophins are discussed.

Maintenance therapy for multiple myeloma with particular emphasis on thalidomide

Treatment standards are changing as a result of new findings in the therapy of multiple myeloma. So far, prednisone, dexamethasone and interferon-a have mainly been used as maintenance therapy after achieving remission or stable disease. At present, thalidomide is being considered as a new therapeutic option in several studies investigating maintenance therapy. As a result of the dose dependence of adverse effects such as neuropathy, constipation, sedation/vertigo and bradycardia, individual adjustment of the thalidomide dose is recommended. Only isolated cases of thrombosis occurred in the maintenance phase of therapy, and discontinuation of therapy is generally not necessary. While important study results on the efficacy of thalidomide following conventional chemotherapy are still awaited, it is the best documented drug so far for maintenance therapy following autologous stem cell transplantation. An upgrade of the response was seen in 22-73% of patients, as well as a significant prolongation of progression-free survival. For the first time, maintenance therapy with thalidomide showed a significant improvement in overall survival in a phase III study published recently. The tolerability of thalidomide could be further improved by including the option of intermittent administration of the drug.

Combined biodifferentiating and antiangiogenic oral metronomic therapy is feasible and effective in relapsed solid tumors in children: single-center pilot study

BACKGROUND

To outline an outpatient-based treatment for children with relapsed solid tumors, who already have been extensively pretreated, we defined a 4-drug protocol named COMBAT (combined oral maintenance biodifferentiating and antiangiogenic therapy). Using this protocol, we performed a pilot study to determine its feasibility in children with relapsed and/or high-risk pediatric solid tumors.

PATIENTS AND METHODS

22 children received the COMBAT protocol. Treatment consisted of daily celecoxib administration along with daily 13-cisretinoic acid (2 weeks on / 2 weeks off) and cycles of metronomic temozolomide (90 mg/m2 for 42 days) and low-dose etoposide (21 days). The treatment was scheduled for a period of 1 year.

RESULTS

9 of the 14 patients assessable for response demonstrated evidence of treatment benefit manifested as prolonged disease stabilization or response. The protocol medication was well tolerated with very good compliance. Only minimal side effects where observed which responded to dose modification or local therapy.

CONCLUSIONS

The COMBAT regimen is well tolerated by patients with intensive prior therapy including myeloablative regimens. Favorable responses observed in this cohort of patients support the further exploration of this and/or similar strategies in the treatment of pediatric solid tumors.

Immunomodulating drugs for chronic lymphocytic leukaemia

Chronic lymphocytic leukaemia (CLL) is a malignant haematological disorder that remains mostly incurable; more than 95% of patients have disease of B-cell origin. Advances with targeted agents such as monoclonal antibodies, antisense therapy, or both these techniques combined with traditional chemotherapy have improved the frequency of remission. The clinical course of CLL is marked by frequent relapse, and there are limited therapeutic options for patients with relapsed or refractory disease. The morphologically mature CLL clone regulates the microenvironment through modulation of the cytokine milieu that aids its growth and survival, and has a role in immune escape. Targeting of the tumour-cell microenvironment has not been investigated as a treatment option for CLL. Immunomodulating agents are a new class of drugs that change expression of various cytokines and that costimulate immune effector cells.

Thalidomide in multiple myeloma

Multiple myeloma is an incurable bone marrow cancer, the treatment of which is notoriously difficult. Only modest advances have been achieved using complex polychemotherapeutic regimens, transplant strategies and supportive therapy. In 1999, when new drugs for myeloma were urgently needed, thalidomide was introduced and opened up a completely new line of therapy for the disease. Although the mechanism of action is not yet completely understood, thalidomide has demonstrated efficacy in patients with refractory, relapsed myeloma, even in late-stage cases. This article reviews the current knowledge of thalidomide in myeloma treatment, focusing especially on the possible mechanisms of action, clinical results and adverse events of this drug.