Dingli, David

ABSTRACT Light chain multiple myeloma (LCMM) is a subtype of multiple myeloma (MM) characterized by the exclusive production of immunoglobulin light chains and accounts for 15%–20% of newly diagnosed MM. A comprehensive comparison of LCMM with MM producing intact immunoglobulin (non‐LCMM) remains limited. In this retrospective study, we described distinct clinical and cytogenetic features and assessed long‐term outcomes in 852 LCMM patients diagnosed between 01/01/2004 and 12/31/2022, compared with non‐LCMM controls matched for age, sex, and year of diagnosis. On univariable analysis, LCMM patients were more likely to present with elevated creatinine (> 2 mg/dL), beta‐2‐microglobulin ≥ 5.5 mg/L, elevated LDH, hypercalcemia, t(11;14), del(13q), and t(6;14). Conversely, IMS‐IMWG high‐risk disease, hyperdiploidy, t(4;14), and serum albumin < 3.5 g/dL were less common. On multivariable analysis, elevated creatinine (OR: 5.1, 95% CI: 1.2–27, p = 0.04), t(11;14) (OR: 2.6, 95% CI: 1.3–5.2, p = 0.006), and del(13q) (OR: 4.1, 95% CI: 2.1–8.2, p < 0.001) were independently associated with LCMM, while IMS‐IMWG high‐risk disease (OR: 0.3, 95% CI: 0.1–0.8, p = 0.02) and hyperdiploidy (OR: 0.3, 95% CI: 0.1–0.7, p = 0.002) were less frequent. Despite these differences, progression‐free survival with frontline treatment (HR: 0.97, 95% CI: 0.84–1.11, p = 0.63) and overall survival (HR: 0.99, 95% CI: 0.87–1.13, p = 0.94) were similar between LCMM and non‐LCMM patients. This study highlights the distinct clinical and cytogenetic features of LCMM, marked by higher rates of renal failure, t(11;14), and del(13q), lower prevalence of IMS‐IMWG high‐risk disease, and comparable survival outcomes.

Abstract This retrospective analysis examined 15 years of autologous stem cell transplantation (ASCT) for light chain (AL) amyloidosis at the Mayo Clinic (2010-2024). We aimed to assess ASCT utilization trends, factors influencing practice changes, and current indications amid newer therapies. Four hundred and forty-one ASCTs were divided into cohort 1 (2010-2019) and cohort 2 (2020-2024), revealing a significant ASCT reduction in cohort 2 (385 vs 56, average 71% annual decrease). Cohort 2 patients were older, more likely to have relapsed/refractory disease, and had higher baseline bone marrow plasma cell burden compared to cohort 1. Pre-ASCT induction was more frequent in cohort 2 (89.3% vs 56.4%), with daratumumab (Dara)–cyclophosphamide-bortezomib-dexamethasone (CyBorD) replacing CyBorD as the predominant induction regimen. Lymphoma-based regimens were also more common in cohort 2 (15.1% vs 5.3%, P = .02). Day-100 satisfactory hematological response improved in cohort 2 (91.1% vs 72.7%, P = .001), although hematological complete response rates did not significantly differ (50.9% vs 38.8%, P = .09). In summary, there is a decrease in the utilization of ASCT in AL amyloidosis. This procedure is primarily reserved for patients with suboptimal responses, relapsed/refractory disease, lymphoplasmacytic clones (predominantly immunoglobulin M amyloidosis), or high bone marrow plasma cell burden (myeloma phenotype). This study underscores a significant shift in ASCT practice, driven by novel therapies, emphasizing more personalized management in AL amyloidosis.

Disease response and progression assessment in multiple myeloma (MM) is based on various measurements of monoclonal protein (serum and urine protein electrophoresis, serum free light chain (FLC, and or quantitative immunoglobulins). Currently, the IMWG consensus response criteria require two sequential assessments of any one marker made at any time before confirmation of disease progression and the institution of any new therapy. However, this can be cumbersome in clinical trials. Herein, we hypothesized that if two markers meet the progression criteria simultaneously, a repeat of either will not be necessary for confirmation. We retrospectively studied all sequential patients with myeloma enrolled in clinical trials at Mayo Clinic. We identified 583 episodes of confirmed progression in our study. Among the 583 progression episodes, nearly 70% (sensitivity of the simultaneous criteria) met the two simultaneous variable criteria at the first testing, indicating progression. Conversely, among 413 patients who met progression criteria by two simultaneous values, 98% (specificity of the simultaneous criteria) of patients subsequently had confirmed progression by sequential values. In summary, for patients with two disease burden markers meeting the simultaneous progression criteria, sequential assessment either one for confirmation may not be necessary to determine disease progression.

ABSTRACT Background Paroxysmal nocturnal haemoglobinuria (PNH) is an ultra‐rare, acquired non‐malignant haematological disorder characterised by thrombosis risk, serious complications and debilitating symptoms in untreated patients. Objective This anchored indirect treatment comparison (ITC) evaluated efficacy data between proximal complement 3 inhibitor (C3i) pegcetacoplan and factor B inhibitor, iptacopan, in patients with PNH previously treated with complement 5 inhibitors (C5i; eculizumab, ravulizumab). Methods Respective pivotal studies provided patient‐level trial data for pegcetacoplan (16‐week PEGASUS [NCT03500549]) and published data for iptacopan (24‐week APPLY PNH [NCT04558918]). Differences in study design, duration and statistical methods between PEGASUS and APPLY PNH necessitated the comparative analyses to be conducted on secondary measures based on haemoglobin (Hb) levels, absolute reticulocyte count (ARC), lactate dehydrogenase (LDH) levels, and patient‐reported outcomes on the Functional Assessment of Chronic Illness Therapy–Fatigue (FACIT‐Fatigue) scale scores. The availability of a common reference C5i treatment group in both PEGASUS and APPLY PNH studies allowed anchored ITC (Bucher method). Simulated treatment comparison (STC) assessed the robustness of the main analysis. Results Overall, baseline characteristics of the populations in the PEGASUS and APPLY PNH studies were broadly comparable. Anchored ITC showed comparable outcomes (mean difference, [95% CI]) on change‐from‐baseline to end of study for pegcetacoplan versus C5i, and iptacopan versus C5i, respectively, across endpoints: Hb level ( − 0.49 g/dL [ − 1.78, 0.80]); ARC ( – 34.41 × 10 9 /L [ − 90.02, 21.21]); LDH level ( − 115.16 U/L [ − 244.40, 14.01]); FACIT‐Fatigue score (3.57 [ − 5.60, 12.73]). Finally, the STC produced results consistent with the main Bucher analyses across all clinical endpoints and patient‐reported fatigue, providing similar point estimates and confidence intervals. Conclusion This anchored ITC, based on data from pivotal trials, did not indicate significant differences in clinical or patient‐reported outcomes between pegcetacoplan and iptacopan in PNH treatment. The findings suggest that PNH treatment decisions should also consider individualised disease‐ and patient‐related factors. Trial Registration: ClinicalTrials.gov identifier: NCT03500549.