Efficacy and toxicity of the combination chemotherapy of thalidomide, alkylating agent, and steroid for relapsed/refractory myeloma patients: a report from the Korean Multiple Myeloma Working Party (KMMWP) retrospective study

What's Old is New: The Past, Present and Future Role of Thalidomide in the Modern-Day Management of Multiple Myeloma

Immunomodulatory drugs (IMiDs) have become an integral part of therapy for both newly diagnosed and relapsed/refractory multiple myeloma (RRMM). IMiDs bind to cereblon, leading to the degradation of proteins involved in B-cell survival and proliferation. Thalidomide, a first-generation IMiD, has little to no myelosuppressive potential, negligible renal clearance, and long-proven anti-myeloma activity. However, thalidomide's adverse effects (e.g., somnolence, constipation, and peripheral neuropathy) and the advent of more potent therapeutic options has led to the drug being less frequently used in many countries, including the US and Canada. Newer-generation IMiDs, such as lenalidomide and pomalidomide, are utilized far more frequently. In numerous previous trials, salvage therapy with thalidomide (50-200 mg/day) plus corticosteroids (with or without selected cytotoxic or targeted agents) has been shown to be effective and well-tolerated in the RRMM setting. Hence, thalidomide-based regimens remain important alternatives for heavily pretreated patients, especially for those who have no access to novel therapies and/or are not eligible for their use (due to renal failure, high-grade myelosuppression, or significant comorbidities). Ongoing and future trials may provide further insights into the current role of thalidomide, especially by comparing thalidomide-containing regimens with protocols based on newer-generation IMiDs and by investigating thalidomide's association with novel therapies (e.g., antibody-drug conjugates, bispecific antibodies, and chimeric antigen receptor T cells).

Treatment of relapsed and refractory multiple myeloma

The therapeutic strategy for relapsed and refractory multiple myeloma (RRMM) integrates a holistic approach regarding patient, disease, and drug-related factors. Patient-related factors include age, frailty status, and underlying comorbidities, especially cardiovascular and renal diseases and peripheral neuropathies that affect tolerability to multiple drug combinations or transplantations. Disease-related factors encompass these multiple patient-related factors, particularly the aggressiveness of the disease and cytogenetics. Regarding drug-related factors, the approval of novel proteasome inhibitors (such as carfilzomib and ixazomib), immunomodulatory agents (such as pomalidomide), monoclonal antibodies (such as daratumumab and elotuzumab), and new classes of drugs increasingly makes the choice treatment more complex and necessitates a comprehensive summary and an update of the efficacy and toxicities of each antimyeloma drug and its combinations. Further, careful monitoring of the side effects and supportive care throughout the course of treatment are important to achieve better outcomes for patients with RRMM.

Analysis of the Efficacy of Thalidomide Plus Dexamethasone-Based Regimens in Patients With Relapsed/Refractory Multiple Myeloma Who Received Prior Chemotherapy, Including Bortezomib and Lenalidomide: KMM-166 Study

BACKGROUND

For patients with multiple myeloma (MM) that relapsed after treatment with bortezomib- and lenalidomide-based regimens, there were no other treatment options in Korea until 2016. We aimed to determine the efficacy of thalidomide plus dexamethasone-based regimens in patients with relapsed/refractory MM (RRMM).

PATIENTS AND METHODS

We conducted a multicenter retrospective analysis in Korea for patients with RRMM treated with thalidomide-based regimens who previously received bortezomib and immunomodulatory agents (IMiDs), including thalidomide and lenalidomide.

RESULTS

In 47 patients with RRMM, the median age was 64 years and the median number of previous treatment lines, including bortezomib and IMiDs, was 3. Primary resistance to bortezomib and lenalidomide was observed in 12 (26%) and 8 (17%) patients, respectively. The most common regimen was a combination of thalidomide, cyclophosphamide, and dexamethasone. The overall response rate was 38%; 2 patients (4%) experienced a complete response, and 2 patients (4%) experienced a very good partial response. The overall response rate of patients previously exposed to thalidomide was 53%. The median progression-free survival was 5.9 months, and overall survival was 9.2 months. Patients with disease that responded to the thalidomide-based regimen had better progression-free survival compared to those who did not (median, 8.8 vs. 2.5 months; P = .008). The most common adverse events were anemia (51%) for hematologic toxicities and peripheral neuropathy (30%) for nonhematologic toxicities.

CONCLUSION

Thalidomide-based regimens are potential salvage treatment options for patients with RRMM, even those with disease with prior resistance to IMiDs.

Efficacy and toxicity of the combination chemotherapy of thalidomide, alkylating agent, and steroid for relapsed/refractory myeloma patients: a report from the Korean Multiple Myeloma Working Party (KMMWP) retrospective study

We analyzed the treatment responses, toxicities, and survival outcomes of patients with relapsed or refractory multiple myeloma who received daily thalidomide, cyclophosphamide, and dexamethasone (CTD) or daily thalidomide, melphalan, and prednisolone (MTP) at 17 medical centers in Korea. Three‐hundred and seventy‐six patients were enrolled. The combined chemotherapy of thalidomide, corticosteroid, and an alkylating agent (TAS) was second‐line chemotherapy in 142 (37.8%) patients, and third‐line chemotherapy in 135 (35.9%) patients. The response rate overall was 69.4%. Patients who were not treated with bortezomib and lenalidomide before TAS showed a higher response rate compared to those who were exposed to these agents. The estimated median progression‐free survival and overall survival times were 10.4 months and 28.0 months, respectively. The adverse events during TAS were generally tolerable, but 39 (10.4%) patients experienced severe infectious complications. There were no differences in terms of efficacy between CTD and MTP, but infectious complications were more common in CTD group. TAS is an effective treatment regimen which induces a high response rate in relapsed or refractory multiple myeloma patients. Due to the high incidence of grade 3 or 4 infection, proper management of infection is necessary during the TAS treatment, especially the CTD.