Outcomes of therapeutic plasma exchange for the treatment of patients with multiple myeloma cast nephropathy.

Current treatment guidelines of myeloma cast nephropathy (MCN) recommend the institution of plasma cell-directed therapy and consideration of therapeutic plasma exchange (TPE), with the goal of rapid reduction of the serum free light chain (sFLC). However, the role of TPE continues to remain a subject of debate. The goal of this retrospective bi-institutional study was to evaluate the clinical outcomes of TPE in combination with systemic therapy. Eighty patients were included in this analysis, of whom 72.5% had ≥50% drop in their initial involved sFLC. At 3 months from TPE initiation, the overall hematologic response rate (ORR) was 67.5% with a very good partial response or better (≥VGPR) rate of 40%. At 6 months, ORR was 57.5%, with ≥VGPR rate of 49%. The renal response rate at 3 and 6 months was 47.5% and 43.75%, respectively; the overall renal response rate was 48.75%. On multivariable analysis, every one unit increase in baseline creatinine (odds ratio [OR] 0.76, p = 0.006), and achievement of ≥VGPR (OR 21.7 p < 0.0001) were significantly associated with renal response. Also, a ≥50% drop in sFLC was favorably associated with renal response (OR 3.39, p = 0.09). With a median follow-up of 36.4 months, the median overall survival (OS) was 11 months. On multivariable analysis, achievement of renal response (hazard ratio [HR] 0.3, p < 0.0001) and newly diagnosed disease (NDMM; HR 0.43, p = 0.0055) were associated with improved OS. Among NDMM patients, those treated with daratumumab-based regimens had a trend for better OS (p = 0.15), compared to other regimens, but the difference was not significant. At the end of follow-up, an estimated 40.4% of patients who were on dialysis were able to become dialysis independent. In conclusion, our study highlights the poor survival of patients with MCN. Achievement of early renal response is crucial for prolonged OS, with daratumumab-based therapies showing promise.

Efficacy and safety of daratumumab, pomalidomide, and dexamethasone versus daratumumab, carfilzomib, and dexamethasone in daratumumab-naïve relapsed multiple myeloma.

OBJECTIVES AND METHODS: We conducted a multicenter retrospective study to analyze the safety and efficacy of DPd versus DKd in daratumumab naïve RRMM patients treated in real-world practice. RESULTS: A total of 187 patients with RRMM were included in the analysis; 128 patients received DPd, and 59 patients received DKd. A vast majority (80%) of patients had lenalidomide refractory disease and nearly 50% had bortezomib refractory disease. The overall response and complete response rates were 76% and 34% in the DPd group versus 80% and 51% in the DKd group, respectively. With a median follow up of 36 months for the entire patient population, median PFS and OS in the DPd versus DKd groups were 12, 12, 37, and 35 months, respectively. The most common grade 3+ adverse events in the DPd versus DKd groups were neutropenia (32% vs. 7%), anemia (14% vs. 10%), thrombocytopenia (13% vs. 15%), and cardiovascular events (4% vs. 15%), respectively. Both DPd and DKd appeared to be a safe and effective treatment options for RRMM. CONCLUSIONS: While there were more cytopenias associated with DPd and more cardiovascular side effects with DKd, there were no significant differences in the survival outcomes with these two regimens.

Outcomes of venetoclax-based therapy in patients with t(11;14) light chain amyloidosis after failure of daratumumab-based therapy.

BACKGROUND: Daratumumab's incorporation in the upfront treatment of light chain (AL) amyloidosis has led to daratumumab (dara) refractoriness early in disease course. Patients who experience relapse or have suboptimal response to dara-based-therapy, have limited options. OBJECTIVE: This study aimed to evaluate the outcomes of venetoclax-based therapy in t(11;14) positive AL patients who previously failed dara. METHODS: Thirty-one patients with AL were included in this bi-institutional retrospective analysis. RESULTS: Dara failure was due to inadequate response in 20 (65%) patients, haematologic relapse in 7 (22%), and both haematologic plus organ relapse in 4 (13%). Overall haematologic response rate to venetoclax-based therapy was 97%, with ≥ VGPR being 91%. Of the 19 evaluable patients with cardiac involvement, 14 (74%) achieved organ response. Of the 13 evaluable patients with renal involvement, 6 (46%) achieved organ response. With a median follow-up of 22 months, median time-to-next-treatment (TTNT) and overall survival (OS) were not reached. The 12- and 24-month TTNT rates were 74% and 56%, respectively. At data-cut-off, four patients had died, all from AL-related organ complications. The 12- and 24-month OS rates were 89% and 85%, respectively. Grade ≥3 adverse events occurred in 26% of patients, with 6% due to infections. CONCLUSION: These findings are encouraging for the use of venetoclax as salvage therapy post-dara failure.

Association of Thrombocytopenia With Disease Burden, High-Risk Cytogenetics, and Survival in Newly Diagnosed Multiple Myeloma Patients Treated With Novel Therapies.

BACKGROUND: The effect of thrombocytopenia has not been studied in the era of novel treatments in multiple myeloma (MM). OBJECTIVE: To evaluate the clinical characteristics and outcomes in MM patients presenting with thrombocytopenia. MATERIALS: Newly diagnosed MM patients between 2008 and 2018 who received at least 2 novel agents at induction. Thrombocytopenia was defined as a platelet count of less than < 150,000/mm3. RESULTS: A total of 648 patients were identified. Thrombocytopenia was found in 120 patients (18.5%). Baseline disease characteristics associated with higher rates of thrombocytopenia at baseline included IgA myeloma, P < .01, ISS 3 versus 1 or 2, P < .01, R-ISS 3 versus 1 or 2, P < .01, renal failure (CrCl < 30 mL/min), P < .01, hypercalcemia (Ca > 11.5 mg/dL), P < .01, elevated LDH, P < .03, anemia (Hb < 10 g/dL), P < .01, higher serum monoclonal protein, P < .02, and > 60% plasma cells in the bone marrow, P < .01. Thrombocytopenia was more prevalent across patients with t(4;14) and t(14;16), but was not associated with an overall high-risk fluorescence in situ hybridization (FISH) classification. Median OS was significantly lower among patients with thrombocytopenia (64.4 vs. 145.0 months, P < .01). In multivariable Cox regression, thrombocytopenia was associated with mortality (HR = 2.45, 95% CI, 1.7-3.6) independently of age, sex, high-risk FISH, ISS stage, response at induction, percentage of plasma cells in the BM, and anemia. CONCLUSION: We found that thrombocytopenia was seen among one-fifth of MM patients and was more common in patients with (t[4; 14] and t[14; 16]). Thrombocytopenia had an independent association with worse survival.

Impact of Extraosseous Extramedullary Disease on Outcomes of Patients with Relapsed-Refractory Multiple Myeloma receiving Standard-of-Care Chimeric Antigen Receptor T-Cell Therapy.

The presence of extramedullary disease (EMD) has been associated with poor outcomes in patients with relapsed-refractory multiple myeloma (RRMM). Herein, we report the outcomes of RRMM patients who were treated with standard-of-care (SOC) chimeric antigen receptor (CAR) T-cell therapy and had active extraosseous EMD before the infusion. Data were retrospectively collected from patients at three US institutions with the intent to receive SOC CAR T. Responses were assessed per the International Myeloma Working Group criteria. A total of 152 patients proceeded with infusion, of whom 47 (31%) had EMD (EMD group) and 105 (69%) did not (non-EMD group). Baseline patient characteristics were comparable between the two groups. The EMD group had a higher incidence of high-grade CRS, steroid and anakinra use, and thrombocytopenia on day +30 compared to the non-EMD group. In addition, the EMD group had an inferior overall response rate (58% vs 96%, p < 0.00001), median progression-free survival (PFS) (5.1 vs 12.4 months; p < 0.0001), and overall survival (OS) (12.2 vs 27.5 months; p = 0.00058) compared to the non-EMD group. We further subdivided the non-EMD patients into those with paramedullary disease (PMD-only group, n = 26 [17%]) and those with neither EMD nor PMD (bone marrow-contained group or BM-only group, n = 79 [52%]). Patients with PMD-only had similar median PFS (11.2 vs 13.6 months, p = 0.3798) and OS (not reached [NR] vs 27.5 months, p = 0.6446) compared to patients with BM-only disease. However, patients with EMD exhibited inferior median PFS (5.1 vs 13.6 months, p < 0.0001) and OS (12.2 vs 27.5, p = 0.0008) compared to patients in the BM-only group. Treatment with SOC CAR T yielded meaningful clinical outcomes in real-world RRMM patients with extraosseous EMD, though responses and survival outcomes were suboptimal compared to patients without EMD. The presence of only EMD but not PMD was associated with significantly worse survival outcomes following the CAR T infusion.

Outcomes of patients with multiple myeloma refractory to standard dose vs low dose lenalidomide.

Refractoriness to lenalidomide is an important factor determining the choice of therapy at first relapse in multiple myeloma (MM). It remains debatable if resistance to lenalidomide varies among MM refractory to standard doses vs low dose maintenance doses. In this study, we assessed the outcomes with subsequent therapies in patients with MM refractory to standard dose vs low dose lenalidomide. We retrospectively reviewed all patients with MM at our institution who received first line therapy with lenalidomide containing regimens, and assessed progression free survival (PFS) and overall survival for these patients for second line therapy, and with lenalidomide retreatment. For second line therapy, we found no difference in the PFS between standard dose refractory and low dose refractory groups (median PFS 14 months vs 14 months, p = 0.95), while the PFS for both these groups was inferior to the not refractory group (median PFS 30 months, p < 0.001 for both pairs). Similar trends were seen among these groups on lenalidomide retreatment, and on multivariable analysis. These data suggest that refractoriness to lenalidomide is not dose dependent, and definition of lenalidomide refractoriness should not depend on the dose of lenalidomide to which the disease was considered refractory.