Safety and efficacy of bortezomib in high-risk and elderly patients with relapsed multiple myeloma

Adverse prognostic factors in multiple myeloma include advanced age, number of prior therapies, and higher International Staging System (ISS) disease stage. In the international, randomised, phase-3 Assessment of Proteasome Inhibition for Extending Remissions (APEX) study, bortezomib demonstrated significantly longer time to progression (TTP), higher response rates and improved survival compared with high-dose dexamethasone in patients with relapsed multiple myeloma following one to three prior therapies. In this APEX subgroup analysis, efficacy of bortezomib and dexamethasone was compared in elderly (age > or =65 years) and high-risk (>1 prior line of therapy; ISS stage II/III; refractory to prior therapy) patients. Bortezomib demonstrated substantial clinical activity in these patients. Response rate (34-40% vs. 13-19%), including complete response rate (5-8% vs. 0-1%), was significantly higher with bortezomib versus dexamethasone in all four subgroups. Similarly, median TTP was significantly longer with bortezomib versus dexamethasone, and 1-year survival probability was significantly higher in all subgroups. As in the total APEX population, rates of grade 3/4 adverse events were higher in bortezomib- versus dexamethasone-treated patients aged > or =65 years and with >1 prior line, while rates of serious adverse events were similar; toxicities generally proved manageable. Bortezomib should be considered an appropriate treatment for elderly and high-risk patients with relapsed multiple myeloma.     

Lenalidomide plus dexamethasone is more effective than dexamethasone alone in patients with relapsed or refractory multiple myeloma regardless of prior thalidomide exposure

This analysis assessed the efficacy and safety of lenalidomide + dexamethasone in patients with relapsed or refractory multiple myeloma (MM) previously treated with thalidomide. Of 704 patients, 39% were thalidomide exposed. Thalidomide-exposed patients had more prior lines of therapy and longer duration of myeloma than thalidomide-naive patients. Lenalidomide + dexamethasone led to higher overall response rate (ORR), longer time to progression (TTP), and progression-free survival (PFS) versus placebo + dexamethasone despite prior thalidomide exposure. Among lenalidomide + dexamethasone-treated patients, ORR was higher in thalidomide-naive versus thalidomide-exposed patients (P = .04), with longer median TTP (P = .04) and PFS (P = .02). Likewise for dexamethasone alone-treated patients (P = .03 for ORR, P = .03 for TTP, P = .06 for PFS). Prior thalidomide did not affect survival in lenalidomide + dexamethasone-treated patients (36.1 vs 33.3 months, P > .05). Thalidomide-naive and thalidomide-exposed patients had similar toxicities. Lenalidomide + dexamethasone resulted in higher rates of venous thromboembolism, myelosuppression, and infections versus placebo + dexamethasone, independent of prior thalidomide exposure. Lenalido-mide + dexamethasone was superior to placebo + dexamethasone, independent of prior thalidomide exposure. Although prior thalidomide may have contributed to inferior TTP and PFS compared with thalidomide-naive patients, these parameters remained superior compared with placebo + dexamethasone; similar benefits compared with placebo + dexamethasone were not evident for thalidomide-exposed patients in terms of overall survival. Studies were registered at http://www.clinicaltrials.gov under NCT00056160 and NCT00424047.     

Characterisation of haematological profiles and low risk of thromboembolic events with bortezomib in patients with relapsed multiple myeloma

Haematological toxicities and thromboembolic (TE) events are common complications of myeloma therapy. TE risk may be elevated with combination regimens, notably thalidomide/lenalidomide plus high-dose dexamethasone; concomitant erythropoietin appears to further increase the risk with lenalidomide-dexamethasone. We characterised thrombocytopenia and neutropenia in the phase 3 APEX (Assessment of Proteasome Inhibition for Extending Remissions) study of bortezomib versus high-dose dexamethasone in relapsed myeloma, and calculated the incidences of deep-vein thrombosis (DVT)/pulmonary embolism (PE) with: bortezomib or dexamethasone +/- erythropoietin in APEX; bortezomib +/- dexamethasone +/- erythropoietin in two phase 2 studies of relapsed/refractory myeloma. Bortezomib-associated thrombocytopenia and neutropenia were transient, predictable and manageable; mean platelet and neutrophil counts followed a cyclical pattern, and improved over the treatment course. Grade 3/4 thrombocytopenia incidence was higher with bortezomib versus dexamethasone (26%/4% vs. 5%/1%), but significant bleeding events were comparable (4% vs. 5%). DVT/PE incidence was low (< or =3.1%) in all analyses; addition of dexamethasone/erythropoietin did not affect TE risk. In APEX, TE risk appeared lower with bortezomib versus dexamethasone. Bortezomib caused transient and cyclical thrombocytopenia and was not associated with elevated TE risk, alone or with dexamethasone +/- erythropoietin. Preliminary data suggest bortezomib may reduce the thrombogenic potential of combination regimens via inhibition of platelet function or other mechanism-specific effects on coagulation.     

Lenalidomide in relapsed refractory myeloma patients: impact of previous response to bortezomib and thalidomide on treatment efficacy. Results of a medical need program in Belgium

The prognosis of multiple myeloma patients has significantly improved since the introduction of the novel agents thalidomide, bortezomib and lenalidomide. We report the data of a medical need programme with lenalidomide plus dexamethasone, conducted in Belgium between August 2007 and March 2008, and including 98 relapsed refractory multiple myeloma patients. In addition to chemotherapy and steroids, all patients had received prior treatment with bortezomib, and 84% of them had been exposed to thalidomide. In 52 patients response data could be retrieved by post-hoc analysis. A partial remission or better was achieved in 52% (49% partial and 3% complete response) of patients, despite a median of 5 previous anti-myeloma treatment lines. Responses were rapid while the majority of patients received lenalidomide with once weekly (also called low-dose) dexamethasone. Treatment with lenalidomide plus dexamethasone did prolong overall survival by nearly half a year in this population with end-stage myeloma. Overall response and quality of response were independent of previous response to thalidomide and bortezomib, although the time to progression tended to be shorter in thalidomide- and bortezomib-refractory patients. It can be concluded that lenalidomide plus dexamethasone is an effective and safe treatment regimen in highly refractory multiple myeloma patients, and that these responses are irrespective of previous exposure or sensitivity to thalidomide and bortezomib.     

Efficacy of bortezomib in systemic AL amyloidosis with relapsed/refractory clonal disease

We report preliminary observations on the efficacy of bortezomib in 20 patients with AL amyloidosis whose clonal disease was active despite treatment with a median of 3 lines of prior chemotherapy, including a thalidomide combination in all cases. Patients received a median of 3 (range 1-6) cycles of bortezomib and 9 (45%) patients received concurrent dexamethasone. Three (15%) patients achieved complete hematologic responses, and a further 13 (65%) achieved partial responses. Fifteen (75%) patients experienced some degree of toxicity, which in 8 (40%) cases resulted in discontinuation of bortezomib. Bortezomib shows promise in the treatment of systemic AL amyloidosis.     

Reversibility of renal failure in newly diagnosed multiple myeloma patients treated with high dose dexamethasone-containing regimens and the impact of novel agents

The impact of high dose dexamethasone containing regimens with or without the novel agents thalidomide and bortezomib on the reversal of renal failure (RF) was evaluated in 41 consecutive newly diagnosed patients with multiple myeloma (MM) treated in a single institution. RF was reversed in 73% of all patients within a median of 1.9 months. In patients treated with dexamethasone and novel agents (thalidomide and/or bortezomib) the reversibility rate was 80% within a median of 0.8 months. Severe RF and significant Bence Jones proteinuria were associated with a lower probability of RF reversal. Patients who responded to treatment achieved RF reversal more often than in those who did not (85% versus 56%, p=0.046). In conclusion, RF is reversible in the majority of newly diagnosed MM patients treated with high-dose dexamethasone containing regimens. The addition of novel agents induces a more rapid RF reversal.     

Efficacy of single-agent bortezomib vs. single-agent thalidomide in patients with relapsed or refractory multiple myeloma: a systematic comparison

OBJECTIVE: To conduct a systematic review of the efficacy of single-agent bortezomib vs. single-agent thalidomide in patients with relapsed/refractory multiple. METHODS: Publications in English from 1966 to June 2005 (MEDLINE, EMBASE, Cochrane library), publication reference lists, Janssen-Cilag data-on-file and abstracts from recent multiple myeloma conferences were reviewed. Prospective studies containing at least a single arm of either treatment group with n> or =30 were included. Studies adding dexamethasone for non-responders were excluded. Statistical pooling was performed for response rate and overallsurvival. RESULTS: One bortezomib study (n = 333, NEJM 2005, 352; 2487-98) and 15 thalidomide (n = 1007) studies met these criteria and were included. Patient baseline characteristics including age, gender, IgG : IgA, disease duration and beta-2 microglobulin were well matched except that 48% of bortezomib patients had received prior thalidomide. Response rate, defined as serum M-protein reduction > or =50%, was 53% for patients receiving bortezomib vs. 32% for thalidomide (P < 0.001, n = 10 studies). Response rate determined by European Group for Blood and Marrow Transplantation (EBMT) criteria was 41% for patients receiving bortezomib vs. 22% for thalidomide (P < 0.001, n = 4 studies). CONCLUSION: Bortezomib was associated with a significantly higher response rate and complete remission rate using both M-protein and EBMT criteria.     

Management of myeloma-associated renal dysfunction in the era of novel therapies

Multiple myeloma (MM) is a plasma cell neoplasm often associated with renal impairment (RI), with myeloma cast nephropathy recognized as the most common cause. While RI is present in over 50% of MM patients at some point in their disease course, it is associated with higher tumor burden, more aggressive disease, diminished quality of life, development of complications and increased mortality. The introduction of novel therapies, including bortezomib, lenalidomide and thalidomide, has revolutionized the management of MM. They are now considered first-line therapies in induction, maintenance and salvage therapy for MM. In addition to their anti-MM effect, they can improve outcome in patients with RI, especially when combined, and bortezomib with dexamethasone may have a renal protective effect. This review focuses on the use of these agents in patients with MM and RI, and evaluates their efficacy, safety, need for dose adjustment and impact on RI.     

Effective combination therapy of bortezomib and dexamethasone for two patients with refractory multiple myeloma

We describe 2 cases of conventional therapy-resistant multiple myeloma (MM) that responded to bortezomib and dexamethasone therapy. Case 1: A 62-year-old woman with MM (IgG, kappa-type, stage IIIA) resistant to DMVM-IFN (dexamethasone, ranimustine, vincristine, melphalan, interferon-a), VAD (vincristine, doxorubicin, dexamethasone), high-dose melphalan with autologous peripheral blood stem cell transplantation (PBSCT) and thalidomide, received 2 courses of bortezomib treatment. In the first course, bortezomib alone was administered and then in the second course bortezomib was given in combination with dexamethasone. The patient's serum IgG level decreased from 8040 to 1020 mg/dl and the level of plasma cells in bone marrow was 1.2% after the treatments. Adverse reactions including rash, anemia, and thrombocytopenia occurred in the first course; however, they were milder in the second course combined with dexamethasone. Case 2: A 43-year-old man with MM (IgD, gamma-type, stage IIA) resistant to conventional and high-dose chemotherapy with PBSCT as well as thalidomide therapy, received treatment with bortezomib alone and then in combination with dexamethasone. His serum IgD level decreased from 2140 to 623 mg/dl. He suffered adverse reactions such as fatigue, anemia, and thrombocytopenia in the first course, which were relieved in the second course. These results indicate that the combination of bortezomib and dexamethasone is effective in the treatment of refractory MM and that dexamethasone can reduce the adverse reactions of bortezomib.     

Superiority of bortezomib, thalidomide, and dexamethasone (VTD) as induction pretransplantation therapy in multiple myeloma: a randomized phase 3 PETHEMA/GEM study

The Spanish Myeloma Group conducted a trial to compare bortezomib/thalidomide/dexamethasone (VTD) versus thalidomide/dexamethasone (TD) versus vincristine, BCNU, melphalan, cyclophosphamide, prednisone/vincristine, BCNU, doxorubicin, dexamethasone/bortezomib (VBMCP/VBAD/B) in patients aged 65 years or younger with multiple myeloma. The primary endpoint was complete response (CR) rate postinduction and post-autologous stem cell transplantation (ASCT). Three hundred eighty-six patients were allocated to VTD (130), TD (127), or VBMCP/VBAD/B (129). The CR rate was significantly higher with VTD than with TD (35% vs 14%, P = .001) or with VBMCP/VBAD/B (35% vs 21%, P = .01). The median progression-free survival (PFS) was significantly longer with VTD (56.2 vs 28.2 vs 35.5 months, P = .01). In an intention-to-treat analysis, the post-ASCT CR rate was higher with VTD than with TD (46% vs 24%, P = .004) or with VBMCP/VBAD/B (46% vs 38%, P = .1). Patients with high-risk cytogenetics had a shorter PFS and overall survival in the overall series and in all treatment groups. In conclusion, VTD resulted in a higher pre- and posttransplantation CR rate and in a significantly longer PFS although it was not able to overcome the poor prognosis of high-risk cytogenetics. Our results support the use of VTD as a highly effective induction regimen prior to ASCT. The study was registered with http://www.clinicaltrials.gov (NCT00461747) and Eudra CT (no. 2005-001110-41).     

A prospective,international phase 2 study of bortezomib retreatment in patients with relapsed multiple myeloma

Multiple myeloma (MM) typically follows a relapsing course with many patients requiring multiple therapies. This single‐arm phase 2 study prospectively evaluated the efficacy and safety of bortezomib retreatment in MM patients who had relapsed after achieving at least a partial response (≥PR) to prior bortezomib‐based therapy. Patients aged ≥18 years, with measurable, secretory MM, who relapsed ≥6 months after prior bortezomib treatment were eligible. Patients received up to eight cycles of bortezomib (±dexamethasone). The primary endpoint was best confirmed response at retreatment; secondary endpoints included duration of response (DOR), time to progression (TTP), and safety. Adverse events (AEs) were graded by National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0. A total of 130 patients (median of two prior lines of therapy) were enrolled and received retreatment. At retreatment, 28% and 72% of patients received bortezomib and bortezomib‐dexamethasone, respectively. Overall response rate was 40%. In patients who achieved ≥PR, median DOR and TTP were 6·5 and 8·4 months, respectively. Thrombocytopenia was the most common grade ≥3 AE (35%). Forty percent of patients experienced neuropathy events, which improved and resolved in a median of 1·5 and 8·9 months, respectively. In conclusion, bortezomib retreatment was effective and tolerable in relapsed MM patients, with no evidence of cumulative toxicities.     

Elotuzumab in combination with thalidomide and low‐dose dexamethasone: a phase 2 single‐arm safety study in patients with relapsed/refractory multiple myeloma

Elotuzumab is an immunostimulatory, humanized immunoglobulin G1 monoclonal antibody that selectively targets and kills signalling lymphocytic activation molecule family member 7–expressing myeloma cells. We evaluated the safety and tolerability of elotuzumab 10 mg/kg combined with thalidomide 50–200 mg and dexamethasone 40 mg (with/without cyclophosphamide 50 mg) in patients with relapsed/refractory multiple myeloma (RRMM). The primary endpoint was the proportion of grade ≥3 non‐haematological adverse events (AEs); other endpoints included the number of dose reductions/discontinuations and efficacy. Forty patients were treated, who had a median of three previous therapies, including bortezomib (98%) and lenalidomide (73%). Grade ≥3 non‐haematological AEs were reported in 63% of patients, most commonly asthenia (35%) and peripheral oedema (25%). Six (15%) patients had an infusion reaction. Twenty‐six (65%) patients had ≥1 dose reduction/discontinuation due to an AE, none related to elotuzumab. Overall response rate was 38%; median progression‐free survival was 3·9 months. Median overall survival was 16·3 months and the 1‐year survival rate was 63%. Minimal incremental toxicity was observed with addition of elotuzumab to thalidomide/dexamethasone with or without cyclophosphamide, and efficacy data suggest clinical benefit in a highly pre‐treated population. Elotuzumab combined with thalidomide may provide an additional treatment option for patients with RRMM.     

Monoclonal antibodies: potential new therapeutic treatment against multiple myeloma

Despite recent treatments, such as bortezomib, thalidomide, and lenalidomide, therapy of multiple myeloma (MM) is limited, and MM remains an incurable disease associated with high mortality. The outcome of patients treated with cytotoxic therapy has not been satisfactory. Therefore, new therapies are needed for relapsed MM. A new anticancer strategy is the use of monoclonal antibodies (MoAbs) that represent the best available combination of tumor cytotoxicity, environmental signal privation, and immune system redirection. Clinical results in patients with relapsed/refractory MM suggest that MoAbs are likely to operate synergistically with traditional therapies (dexamethasone), immune modulators (thalidomide, lenalidomide), and other novel therapies (bortezomib); in addition, MoAbs have shown the ability to overcome resistance to these therapies. It remains to be defined how MoAb therapy can most fruitfully be incorporated into the current therapeutic paradigms that have achieved significant survival earnings in patients with MM. This will require careful consideration of the optimal sequence of treatments and their clinical position as either short‐term induction therapy, frontline therapy in patients ineligible for ASCT, or long‐term maintenance treatment.     

Current status of new drugs for the treatment of patients with multiple myeloma

Multiple myeloma, a malignant disorder of plasma cells, is the second most common haematological malignancy. Although treatable, multiple myeloma remains incurable in virtually all cases, with a median survival of 3-4 years. Fortunately for patients with this disease, traditional treatment paradigms have been challenged with the emergence of a number of new therapies entering clinical practice over the last 6 years. In this review, we focus on the use of thalidomide (Thalidomide Pharmion; Boulder, CO, USA), lenalidomide (Revlimid; Celgene Corporation, Summit, NJ, USA) and bortezomib (Velcade; Janssen Pharmaceutica N.V., Belgium) in the treatment of myeloma. We present the current clinical experience with respect to efficacy and toxicity of these promising new agents and how the incorporation of these drugs with traditional therapies may improve the outcome for patients with multiple myeloma.     

A Multicenter Retrospective Analysis of Adverse Events in Korean Patients Using Bortezomib for Multiple Myeloma

The proteasome inhibitor bortezomib has demonstrated clinical activity in patients with multiple myeloma (MM). Adverse events, including thrombocytopenia and peripheral neuropathy, have affected 30% to 60% of patients overall, and interrupted therapy in 10% to 20%. No prior toxicity data are available for Asian patients who have used bortezomib for MM. We used National Cancer Institute Common Terminology Criteria for Adverse Events, version 3.0, to review the clinical records of patients with an MM diagnosis from 25 centers in Korea. The included patients were treated with bortezomib alone or in combination with other agents, including thalidomide. Ninety-five MM patients were treated. The patients had a median age of 60 years (range, 42-77 years). The median number of previous treatments was 3 (range, 0-10), and 39% of the patients had been treated with 4 or more major classes of agents, including thalidomide (67%), and autologous stem cell transplantation (51%). Regimens included bortezomib only in 38 patients (40%), bortezomib plus dexamethasone in 34 patients (36%), and bortezomib plus a thalidomide-containing regimen in 23 patients (24%). The analysis of patient response to therapy revealed a complete response (CR) or a near-CR in 31 patients (33%) and a partial response in 30 patients (32%), for an objective response rate of 65% in 93 patients. The most common adverse events reported were thrombocytopenia (47%), sensory neuropathy (42%), anemia (31%), and leukopenia (31%). Thirteen patients (14%) stopped therapy because of adverse events (neuropathy, 8; infection, 4; diarrhea, 1). Neuropathy greater than grade 2 was more frequent in patients who received 4 or more prior therapy regimens (17/37) than in those who received 3 or fewer (14/58). In addition, therapy including thalidomide was significantly correlated with neuropathy of grades 1 to 3 (P = .001). We identified 6 therapy-related deaths (6%) within 20 days after the last dose of bortezomib. The causes of death were infection in 3 patients, disease progression in 2 patients, and suicide in 1 patient. The incidences of thrombocytopenia and neurotoxicity were similar; however, gastrointestinal toxicities were relatively low in Korean patients compared with those reported in Western studies. Significant neuropathy was associated with the number of prior regimens and combination with thalidomide. These findings provide useful information for clinicians and patients using bortezomib.     

Bortezomib combination therapy in multiple myeloma

Bortezomib was approved for the treatment of multiple myeloma (MM) in 2003. Since then several bortezomib-based combination therapies have emerged. Although some combinations have been preceded by preclinical investigations, most have followed the inevitable process in which active (or potentially active) drugs are combined with each other to create new treatment regimens. Regimens that have combined bortezomib with corticosteroids, alkylating agents, thalidomide, and/or lenalidomide have resulted in high response rates. Despite the higher and often deeper response rates and prolongation of progression-free survival with bortezomib-based multiagent regimens, an overall survival (OS) advantage has not been demonstrated with most combinations compared to the sequential approach of using anti-myeloma agents, particularly in patients less than 65 years of age with newly diagnosed myeloma. The unique properties of some of these regimens can be taken into account when choosing a particular regimen based on the clinical scenario. For example, the combination of bortezomib, thalidomide, and dexamethasone (VTD) has particular value in renal failure since none of the drugs need dose modification. Similarly, the combination chemotherapy regimen VDT-PACE (bortezomib, dexamethasone, thalidomide, cisplatin, doxorubicin, cyclophosphamide, and etoposide) is of particular value in patients presenting with aggressive disease such as extramedullary plasmacytomas or plasma cell leukemia. Ongoing clinical trials are testing combinations of bortezomib with several other classes of agents, including monoclonal antibodies, and inhibitors of deacetylases, heat shock proteins, phosphatidyl inositol 3-kinase/Akt/mammalian target of rapamycin pathway and farnesyl transferase.     

Extended follow-up of a phase 3 trial in relapsed multiple myeloma: final time-to-event results of the APEX trial

Initial analysis of the Assessment of Proteasome Inhibition for Extending Remissions (APEX) trial of relapsed multiple myeloma patients showed significantly longer time to progression, higher response rate, and improved survival with single-agent bortezomib versus high-dose dexamethasone. In this updated analysis (median follow-up: 22 months), survival was assessed in both arms, and efficacy updated for the bortezomib arm. Median survival was 29.8 months for bortezomib versus 23.7 months for dexamethasone, a 6-month benefit, despite substantial crossover from dexamethasone to bortezomib. Overall and complete response rates with bortezomib were 43% and 9%, respectively; among responding patients, 56% improved response with longer therapy beyond initial response, leading to continued improvement in overall quality of response. Higher response quality (100% M-protein reduction) was associated with longer response duration; response duration was not associated with time to response. These data confirm the activity of bortezomib and support extended treatment in relapsed multiple myeloma patients tolerating therapy.     

Thalidomide versus dexamethasone for the treatment of relapsed and/or refractory multiple myeloma: results from OPTIMUM, a randomized trial

Background

Thalidomide has potent antimyeloma activity, but no prospective, randomized controlled trial has evaluated thalidomide monotherapy in patients with relapsed/refractory multiple myeloma.

Design and Methods

We conducted an international, randomized, open-label, four-arm, phase III trial to compare three different doses of thalidomide (100, 200, or 400 mg/day) with standard dexamethasone in patients who had received one to three prior therapies. The primary end-point was time to progression.

Results

In the intent-to-treat population (N=499), the median time to progression was 6.1, 7.0, 7.6, and 9.1 months in patients treated with dexamethasone, and thalidomide 100, 200, and 400 mg/day, respectively; the difference between treatment groups was not statistically significant. In the per-protocol population (n=465), the median time to progression was 6.0, 7.0, 8.0, and 9.1 months, respectively. In patients who had received two or three prior therapies, thalidomide significantly prolonged the time to progression at all dose levels compared to the result achieved with dexamethasone. Response rates and median survival were similar in all treatment groups, but the median duration of response was significantly longer in all thalidomide groups than in the dexamethasone group. Adverse events reported in the thalidomide groups, such as fatigue, constipation and neuropathy, confirmed the known safety profile of thalidomide.

Conclusions

Although thalidomide was not superior to dexamethasone in this randomized trial, thalidomide monotherapy may be considered an effective salvage therapy option for patients with relapsed/refractory multiple myeloma, particularly those with a good prognosis and those who have received two or three prior therapies. The recommended starting dose of thalidomide monotherapy is 400 mg/day, which can be rapidly reduced for patients who do not tolerate this treatment. (Clinical trial registration number: {"type":"clinical-trial","attrs":{"text":"NCT00452569","term_id":"NCT00452569"}}NCT00452569)     

The potential benefits of participating in early-phase clinical trials in multiple myeloma: long-term remission in a patient with relapsed multiple myeloma treated with 90 cycles of lenalidomide and bortezomib

We present the case of a woman with relapsed multiple myeloma (MM) who received combination lenalidomide and bortezomib therapy for 90 cycles followed by continuous lenalidomide monotherapy and has completed over 100 cycles of treatment to date. The patient was diagnosed with advanced-stage, symptomatic MM in 2001. Following a partial response (PR) to dexamethasone in combination with pamidronate and thalidomide, the patient underwent protocol-directed non-myeloablative allogeneic bone marrow transplantation from her matched sibling donor the following year. In 2004, the patient relapsed and was enrolled in a phase I, dose-escalation trial of lenalidomide plus bortezomib for relapsed and refractory MM. After eight cycles of study treatment, the patient achieved a minimal response. The patient received a total of 90 cycles of treatment with lenalidomide 5 mg given for 14 d every 21 d, and 1 mg/m(2) of bortezomib initially given on days 1, 4, 8, and 11 for the first 20 cycles, and then weekly thereafter on days 1 and 8. Bortezomib was discontinued after 90 cycles, and the patient continued to receive lenalidomide monotherapy. As of cycle 100, the patient achieved a PR. Currently, she is clinically stable with response sustained for over 7 yrs. Therapy has been well tolerated with no significant long-term toxicity; no dose reductions of lenalidomide and bortezomib were required. The excellent tolerability of this steroid-free approach and the durable response seen underscore the potential benefits of participating in early-phase clinical trials evaluating novel therapies and new drug combinations. This case further supports that combination treatment with lenalidomide and bortezomib is an effective therapy in the management of patients with relapsed and refractory MM.     

Practical management of adverse events in multiple myeloma: Can therapy be attenuated in older patients?

The current standard of care for elderly patients with newly diagnosed multiple myeloma is melphalan and prednisone (MP) in combination with either bortezomib (VMP) or thalidomide (MPT), with lenalidomide plus dexamethasone increasingly being employed. The addition of bortezomib or thalidomide to the established MP regimen significantly improves outcomes and prolongs survival in elderly and transplant-ineligible patients. However, these benefits are accompanied by increases in treatment-related adverse events (AEs), which may be particularly pronounced in older individuals. Patients receiving bortezomib as part of a VMP regimen commonly experience transient and cyclical thrombocytopenia and neutropenia, along with gastrointestinal AEs. Fortunately, these AEs can be managed with appropriate supportive care and, when necessary, adjustments in dose. Peripheral neuropathy (PN) is the most important side effect of bortezomib, and although it is reversible in a high proportion of patients, it affects their quality of life. Furthermore, PN can require temporary or permanent withholding of bortezomib, which will reduce treatment efficacy. PN is also a common adverse effect of thalidomide; thromboembolic events are also a key concern, requiring thromboprophylaxis in patients receiving thalidomide in combination. For lenalidomide in combination with dexamethasone, the most clinically important adverse effects are hematologic toxicity (particularly neutropenia) and thromboembolic events. Recent phase III studies in newly diagnosed elderly patients are providing further insight into the most appropriate treatment regimens to maximize outcomes and minimize toxicity in individual patients. Of note, once-weekly bortezomib dosing (in combination with MP±T) was shown to reduce the incidence of peripheral neuropathy and gastrointestinal events compared with twice-weekly dosing, while maintaining efficacy. Elderly patients may be less able to withstand the AEs associated with newer treatment regimens and combinations of multiple drugs, and may experience greater declines in quality of life and, subsequently, reduced treatment adherence. It is therefore critical that these patients are closely monitored and any emergent AEs promptly and appropriately managed. For very elderly, frail patients, tailored therapy, reduced intensity regimens, and adverse event management are necessary to encourage treatment adherence and reduce discontinuation. This article will provide practical guidance on the management of bortezomib-, thalidomide-, and lenalidomide-associated AEs, to maximize treatment feasibility and active drug delivered, and thus help minimize toxicity and maximize outcomes.