Outcomes with autologous stem cell transplant vs. non-transplant therapy in patients 70 years and older with multiple myeloma

The Effect of Age on High-Dose Therapy with Autologous Stem Cell Support in Multiple Myeloma: A Single-Center Experience

Background: This retrospective one-center study demonstrates the complications related to high-dose therapy with autologous stem cell support (HDT) and the survival of multiple myeloma (MM) patients according to age groups. Methods: We categorized the patients into two groups: those who were ≤65 years old (group 1) (N = 115) and those who were >65 years old (group 2) (N = 26). The mean duration of follow-up was 48 (1-125) months. Results: In group 2 patients, the use of a reduced dosage of melphalan (12 [46%] versus 30 [26%]) was more frequent in comparison to group 1 (p = 0.046). There was a statistically significant difference between the two groups regarding the neutrophil engraftment days (p = 0.001) and the median progression-free survival (PFS) (p = 0.02). The PFS was 44 months for group 1 and 30 months for group 2. There was no statistically significant difference between the groups in relation to the median duration of hospitalization, presence of bacteremia, intravenous antibiotic administration, and overall survival (OS). Conclusions: The study's results indicate that HDT is a reliable method of treatment for older patients with MM, provided that they obtain a suitable conditioning regimen and, furthermore, these patients achieved a comparable OS rate to that of younger patients.

Cellular therapies in older adults with hematological malignancies: A case-based, state-of-the-art review

Cellular therapies, including autologous stem cell transplant (ASCT), allogeneic hematopoietic cell transplantation (alloHCT), and chimeric antigen receptor- (CAR-) T cell therapies are essential treatment modalities for many hematological malignancies. Although their use in older adults has substantially increased within the past decades, cellular therapies represent intensive treatment approaches that exclude a large percentage of older adults due to comorbidities and frailty. Under- and overtreatment in older adults with hematologic malignancy is a challenge and many treatment decisions are influenced by chronologic age. The advent of efficient and well-tolerated newer treatment approaches for multiple myeloma has challenged the role of ASCT. In the modern era, there are no randomized clinical trials of transplant versus non-transplant strategies for patients ≥65 years. Nonetheless, ASCT is feasible for selected older patients and does not result in long-term compromise in quality of life. AlloHCT is the only curative approach for acute myeloid leukemia of intermediate and unfavourable risk but carries a significant risk for non-relapse mortality depending on comorbidities, general fitness, and transplant-specific characteristics, such as intensity of conditioning and donor choice. However, alloHCT is feasible in appropriately-selected older adults. Early referral for evaluation is strongly encouraged as this is the most obvious barrier. CAR-T cell therapies have shown unprecedented clinical efficacy and durability in relapsed and refractory diffuse large B cell lymphoma. Its use is well tolerated in older adults, although evidence comes from limited case numbers. Whether patients who are deemed unfit for ASCT qualify for CAR-T cell therapy remains elusive, but the tolerability and efficacy of CAR-T cell therapy appears promising, especially for older patients. The evidence from randomized trials is strong in favor of using a comprehensive geriatric assessment (CGA) to reduce treatment-related toxicities and guide treatment intensity in the care for solid tumors; its use for evaluation of cellular therapies is less evidence-based. However, CGA can provide useful information on patients' fitness, resilient mechanisms, and reveal potential optimization strategies for compensating for vulnerabilities. In this narrative review, we will discuss key questions on cellular therapies in older adults based on illustrative patient cases.

Treatment benefit of upfront autologous stem cell transplantation for newly diagnosed multiple myeloma: a systematic review and meta-analysis

BACKGROUND

Upfront high-dose therapy (HDT) followed by autologous stem cell transplantation (ASCT) remains a profitable strategy for newly diagnosed multiple myeloma (MM) patients in the context of novel agents. However, current knowledge demonstrates a discrepancy between progression-free survival (PFS) and overall survival (OS) benefit with HDT/ASCT.

METHODS

We conducted a systematic review and meta-analysis that included both randomized controlled trials (RCTs) and observational studies evaluating the benefit of upfront HDT/ASCT published during 2012 to 2023. Further sensitivity analysis and meta-regression were also performed.

RESULTS

Among the 22 enrolled studies, 7 RCTs and 9 observational studies had a low or moderate risk of bias, while the remaining 6 observational studies had a serious risk of bias. HDT/ASCT revealed advantages in complete response (CR) with an odds ratio (OR) of 1.24 and 95% confidence interval (CI) 1.02 ~ 1.51, PFS with a hazard ratio (HR) of 0.53 (95% CI 0.46 ~ 0.62), and OS with an HR of 0.58 (95% CI 0.50 ~ 0.69). Sensitivity analysis excluding the studies with serious risk of bias and trim-and-fill imputation fundamentally confirmed these findings. Older age, increased percentage of patients with International Staging System (ISS) stage III or high-risk genetic features, decreased proteasome inhibitor (PI) or combined PI/ immunomodulatory drugs (IMiD) utilization, and decreased follow-up duration or percentage of males were significantly related to a greater survival advantage with HDT/ASCT.

CONCLUSIONS

Upfront ASCT remains a beneficial treatment for newly diagnosed MM patients in the period of novel agents. Its advantage is especially acute in high-risk MM populations, such as elderly individuals, males, those with ISS stage III or high-risk genetic features, but is attenuated with PI or combined PI/IMiD utilization, contributing to divergent survival outcomes.

Melflufen for the treatment of multiple myeloma

INTRODUCTION

Melphalan flufenamide (melflufen) is a first-in-class peptide-drug conjugate that takes advantage of increased aminopeptidase activity inside tumor cells to rapidly release alkylating agents therein. Melflufen in combination with dexamethasone has been evaluated in multiple clinical trials in patients with relapsed/refractory multiple myeloma (MM).

AREAS COVERED

This profile covers the unique mechanism of action of melflufen, the preclinical results supporting its activity in cellular models of resistance to chemotherapy, its activity in animal models of MM, and the clinical pharmacokinetics of melflufen. Findings from clinical trials evaluating melflufen, including the pivotal phase II HORIZON study and the phase III OCEAN study, are discussed.

EXPERT OPINION

Although MM treatment has improved, patients with disease refractory to multiple standard-of-care drug classes face a dismal prognosis. Melflufen demonstrated efficacy and tolerability in select populations, with an initial approval in the United States in patients with ≥ four previous lines of therapy and triple-class-refractory MM. Results from the phase III OCEAN study - currently under discussion with regulatory agencies in the United States and Europe - are more complex and have been put into context herein. Lastly, melflufen provides a proof-of-concept for the utility of the peptide-drug conjugate platform in relapsed/refractory MM.

Autologous stem cell transplantation in multiple myeloma patients over 70 years: A GIMEMA Lazio Working Group experience in a retrospective case-control study

High-dose chemotherapy followed by autologous stem cell transplantation (auto-SCT) is the standard treatment for young patient ≤65 years with multiple myeloma (MM). The role of auto-SCT in elderly patients older than 70 years remains controversial in the era of novel agents and especially since the recent introduction of monoclonal antibodies (AbMo). In this study, we evaluated 12 patients with MM over 70 years old undergoing auto-SCT (elderly graft cohort) in seven centers of GIMEMA Working Group Lazio. We compared the baseline characteristics, treatment and outcome with 97 MM elderly patients who did not receive auto-SCT (nontransplant patients) from the same registry who were ≥ 70 years old, but did not undergo auto-SCT. The median progression free survival (PFS) for graft versus no-graft cohort was 56.4 versus 26.1 months, respectively. There was a trend for better PFS among graft compared to nontransplant patient (p = .1). On the other hand, the median overall survival for transplant versus nontransplant cohort was 107.6 versus 49.5 months (p = .02). Despite the small number of patients aged ≥70 years and ≤74 years, it seems that auto-SCT is well tolerated, safe and effective. Therefore, we propose that it should be considered an important treatment option in the era of new drugs in elderly fit patients with MM.

[Efficacy and safety of autologous hematopoietic stem cell transplantation in elderly multiple myeloma patients: a single center retrospective study]

Objective: To evaluate the efficacy and safety of autologous hematopoietic stem cell transplantation (auto-HSCT) in elderly patients (≥65 years old) with multiple myeloma (MM) . Methods: From June 1, 2006 to July 31, 2020, 22 MM patients (≥65 years old) who were diagnosed in the First Affiliated Hospital, Sun Yat-sen University and received novel drug induction followed by auto-HSCT were analyzed retrospectively. These patients were evaluated for important organ functions before transplantation, and the International Myeloma Working Group frail score was used in 2016 to screen out transplant-eligible patients. Results: The median (interquartile range, IQR) age at the time of transplantation of the 22 patients was 66.75 (IQR 4.50) years. A total of 20 patients received stem cell mobilization. The median number of mononuclear cells collected was 4.53×10(8)/kg, that of CD34(+) cells was 3.37×10(6)/kg, and the median number of apheresis procedures performed was 2. After stem cell transfusion, the median time of neutrophil implantation was 11 days, that of platelet implantation was 13 days, and the treatment-related mortality was 0 at 100 days after transplantation. The median follow-up was 48.7 months. The median time to progression time was not reached, and the median overall survival time was 111.8 months. Conclusion: Auto-HSCT is a safe and effective treatment for selected elderly patients of 65 years or older with MM.