Use of bone-modifying agents and clinical outcomes in older adults with multiple myeloma

The effect of immunomodulatory drugs on bone metabolism of patients with multiple myeloma

INTRODUCTION

Immunomodulatory drugs (IMiDs) are widely used in the management of newly diagnosed and relapsed/refractory multiple myeloma patients. These agents show their potential effect on myeloma bone disease (MBD), including inhibition of osteoclasts activity and effects on osteoblasts differentiation. It is unclear whether these effects are direct, which may have an impact on bone formation markers when combined with proteasome inhibitors.

AREAS COVERED

This review summarizes the available evidence on the role of IMiDs in microenvironment regulation and their potential effects on bone metabolism. The literature search methodology consisted of searching PubMed for basic and clinical trials using medical subject terms. Included articles were screened and evaluated by the coauthors of this review.

EXPERT OPINION

As a therapeutic option, IMiDs directly affect preosteoblast/osteoclast differentiation. The combination of proteasome inhibitors may counteract the short-term up-regulation of osteogenic activity markers, and therefore intravenous zoledronic acid is recommended, however, obtaining a more significant myeloma response will have a long-term positive impact on myeloma bone disease.

Multiple-Drugs-Related Osteonecrosis of the Jaw in a Patient Affected by Multiple Myeloma: A Case Report

A 60-year-old woman suffering from multiple myeloma (MM) was treated with zoledronic acid (bisphosphonate), dexamethasone (corticosteroid), bortezomib (a chemotherapeutic agent), and lenalidomide (thalidomide analog) for about a year and with lenalidomide alone as maintenance therapy for almost two years and developed stage three medication-related osteonecrosis of the jaws (MRONJ) in the upper left dental arch approximately two weeks after tooth extraction, which was treated with a medical nonoperative conservative approach until reversion to stage one. The present case report describing the development of multi-drug-related osteonecrosis of the jaws during the pharmacologic MM maintenance phase draws attention to the complex multidisciplinary and multistage management of MM subjects and also that during disease remission, crucially involving oral healthcare providers for MRONJ prevention and pharmacovigilance. To prevent similar cases, cancer patient management should ensure proper dental care not only before starting but also throughout therapy duration and ensure continuous interdisciplinary consensus between oncologists and dentists. Moreover, also considering the independent negative and potentially synergistic effect on bone metabolism and mucosal healing processes of employed medicaments, additionally combined with the cumulative one of previous intravenous bisphosphonates, further studies should highlight the polypharmacy effect and hopefully aid in patient-specific MRONJ risk assessment in cancer patients.

Outcomes of lenalidomide- or bortezomib-based regimens in older patients with plasma cell myeloma

The "triplet" regimen of lenalidomide, bortezomib, and dexamethasone (RVD) showed survival advantage over lenalidomide-dexamethasone (RD) in clinical trials, but older patients with myeloma often receive doublet regimens (RD or bortezomib-dexamethasone, VD), or VD plus cyclophosphamide (VCD). We compared these first-line regimens using real-world data from Medicare beneficiaries receiving therapy between 2007 and 2015. In each comparative analysis, we balanced confounding characteristics using a propensity score. Outcomes included overall (OS) and event-free survival (EFS, reporting hazard ratios [HR] with 95% confidence intervals [CI]), adverse events, and costs. We identified 6076 patients with median age 76 and median OS of 2.6 years. In the comparison of RVD vs RD/VD doublets, RVD showed significantly better OS (HR = 0.83; 95% CI, 0.72-0.95) and EFS (HR = 0.68; 95% CI, 0.61-0.76). So, RVD was associated with more frequent hospitalizations, anemia, and neuropathy, but no increase in thromboembolism or secondary cancers. Costs were higher with RVD. In the comparison of RD vs VD, RD demonstrated better EFS (HR = 0.74; 95% CI, 0.68-0.81) and marginally better OS (HR = 0.91; 95% CI, 0.83-0.99). And, RD resulted in significantly more thromboembolic events, less neuropathy, and no significant difference in hospitalizations, transfusions, or secondary cancers. In the comparison of VCD vs VD, we observed no significant difference in any outcome. Superior survival favors RVD over doublet regimens, but even in 2015 RVD was applied for only about 25% of Medicare beneficiaries with myeloma. For patients not eligible for RVD due to toxicity, VCD offers no survival benefit over VD. Lenalidomide-dexamethasone may be the preferred line doublet considering its advantage over VD.

Use of bone-modifying agents and clinical outcomes in older adults with multiple myeloma

Background

Guidelines recommend bone‐modifying agents (BMAs) for all patients initiating treatment for myeloma. We examined adherence to this recommendation, and BMA effectiveness in the era of bortezomib/lenalidomide‐based therapy among Medicare beneficiaries.

Methods

From the linked Surveillance, Epidemiology, and End Results‐Medicare registry, we selected beneficiaries receiving anti‐myeloma chemotherapy in 2007‐2013. We matched BMA recipients (within 90 days of first chemotherapy) to nonrecipients using a propensity score, balancing patient‐, disease‐, and therapy‐related confounders. Cumulative incidence of skeletal‐related events (SREs) and overall survival (OS) was compared in proportional hazard models accounting for competing risks and immortal‐time bias.

Results

Among 4611 patients with median age of 76 years, 51% received BMA. Bone‐modifying agents use remained steady over time (P = .87) and was significantly less frequent for patients who were older, with comorbidities, without prior SRE, and those treated without bortezomib or lenalidomide. In a propensity score‐matched cohort, BMA recipients experienced a lower incidence of SRE (11.0% vs 14.6% at 3 years; subhazard ratio, 0.73; 95% CI, 0.60‐0.89) and better OS (53.3% vs 47.8% at 3 years; hazard ratio, 0.86; 95% CI, 0.77‐0.95). The results were consistent in the subgroup (76%) treated with bortezomib and/or immunomodulatory drugs (IMiDs). The incidence of osteonecrosis of the jaw (ONJ) was 3.2% at 3 years.

Conclusions

In this observational study, the observed benefits of early BMA administration among patients treated with contemporary anti‐myeloma regimens were similar to historical clinical trials. Frequent omission of BMA highlights a remediable deficiency in the quality of supportive care, and suggests that timely administration may be a useful indicator of quality care in myeloma.