Faculty Bibliography

In the phase 3 CEPHEUS study, daratumumab plus bortezomib/lenalidomide/dexamethasone (D‑VRd) increased overall MRD-negativity rates versus VRd in transplant-ineligible/transplant-deferred patients with NDMM. We present an expanded MRD analysis of CEPHEUS. Patients who were transplant-ineligible, or deferred transplant as initial therapy, were randomized 1:1 to receive D-VRd or VRd. Overall MRD negativity (NGS) was defined as the proportion of patients achieving ≥CR and MRD-negative status assessed at 10-5 (primary endpoint) and 10-6 thresholds. A total of 395 patients were randomized (D-VRd, n=197; VRd, n=198). With 58.7-months median follow-up, overall MRD-negativity rates were significantly higher with D-VRd versus VRd (10-5, 60.9% vs 39.4%; OR, 2.37; 95% CI, 1.58-3.55; 10-6, 46.2% vs 27.3%; OR, 2.24; 95% CI, 1.48-3.40; P<0.0001 and P=0.0001, respectively). Sustained MRD negativity (≥12 months) was also significantly higher with D-VRd versus VRd (10-5: 49.2% vs 27.3%; 10-6: 34.0% vs 16.2%; each P<0.0001), with similar benefits at ≥24 and ≥36 months. MRD-negativity rates were higher at all pre-specified timepoints, and cumulatively, with D-VRd versus VRd (10-5 and 10-6). Among patients who achieved MRD negativity, PFS trended in favor of D-VRd versus VRd (10-5, HR, 0.61; 95% CI, 0.35-1.06; P=0.0755; 10-6, 0.66; 95% CI, 0.31-1.41; P=0.2811). Responses with D-VRd are deeper and more durable versus VRd, increasing overall, sustained, and landmark MRD-negativity rates, translating into improved overall PFS for patients treated with D-VRd versus VRd (intent-to-treat), with the potential to improve PFS even among patients who achieve MRD negativity. D-VRd is therefore a new standard-of-care treatment for transplant-ineligible/transplant-deferred NDMM. Registered at www.clinicaltrials.gov: NCT03652064.

We carried out a single-cell (sc) multiomic analysis on a series of MYD88 mutated Waldenström macroglobulinemia (WM) cases and identified two distinct subtypes of disease, memory B-cell-like (MBC-like) and plasma cell-like (PC-like), based on their expression of key lineage defining genes. Biologically, the subtypes are characterized by their variable capacity to differentiate fully towards a plasma cell (PC) and exhibit unique transcriptomic, chromatin accessibility, and genomic profiles. The MBC-like subtype is unable to differentiate beyond the memory B-cell (MBC) stage, upregulates key MBC genes, and is characterized by upregulated BCR and AKT/mTOR signaling. In contrast, the PC-like subtype can partially differentiate towards a PC, upregulates key PC genes, has enhanced NF-kB signaling, and has an upregulated unfolded protein response. Pseudotime trajectory analysis of combined scRNA-sequencing and scATAC-sequencing supports the variable differentiation capacity of each subtype and implicate key transcription factors SPI1, SPIB, BCL11A, and XBP1 in these features. The existence and generalizability of the two disease subtypes were validated further using hierarchical clustering of bulk RNA-seq data from a secondary set of cases. The biological significance of the subtypes was further established using whole genome sequencing, where it was shown that CXCR4, NIK, and ARID1A mutations occur predominantly in the MBC-like subtype and 6q deletions in the PC-like subtype. We conclude that the variable differentiation blockade seen in WM manifests itself clinically as two disease subtypes with distinct epigenetic, mutational, transcriptional, and clinical features with potential implications for WM treatment strategies.

Frontline daratumumab-based triplet and quadruplet standard-of-care regimens have demonstrated improved survival outcomes in newly diagnosed multiple myeloma (NDMM). For patients with transplant-ineligible NDMM, triplet therapy with either daratumumab plus lenalidomide and dexamethasone (D-Rd) or bortezomib, lenalidomide and dexamethasone (VRd) is the current standard of care. This phase 3 trial evaluated subcutaneous daratumumab plus VRd (D-VRd) in patients with transplant-ineligible NDMM or for whom transplant was not planned as the initial therapy (transplant deferred). Some 395 patients with transplant-ineligible or transplant-deferred NDMM were randomly assigned to eight cycles of D-VRd or VRd followed by D-Rd or Rd until progression. The primary endpoint was overall minimal residual disease (MRD)-negativity rate at 10^-

Autologous stem cell transplantation (ASCT) is a standard of care treatment for patients with multiple myeloma (MM). However, only 20% to 30% of patients with MM for whom the procedure is indicated undergo ASCT. Barriers to ASCT may be informational, financial, logistic, or cultural and may affect patients and treating oncologists. Available and accessible accurate ASCT-related information is essential to overcome these barriers. Such resources can be created by blood and marrow transplantation societies and patient advocacy groups, ideally in collaboration with MM specialists at transplant centers. An umbrella office at the society level is also recommended to connect oncologists, advocacy groups, and transplantation specialists; provide informational resources to patients; and conduct research into region- and population-specific barriers to ASCT.

PURPOSE/OBJECTIVE:Chromosome 1 (chr1) copy number abnormalities (CNAs) and structural variants (SV) are frequent in newly diagnosed multiple myeloma (NDMM) and associate with a heterogeneous impact on outcome the drivers of which are largely unknown. EXPERIMENTAL DESIGN/METHODS:A multiomic approach comprising CRISPR, gene mapping of CNA and SV, methylation, expression, and mutational analysis was used to document the extent of chr1 molecular variants and their impact on pathway utilisation. RESULTS:We identified two distinct groups of gain(1q): focal gains associated with limited gene expression changes and a neutral prognosis, and whole-arm gains, which associate with substantial gene expression changes, complex genetics and an adverse prognosis. CRISPR identified a number of dependencies on chr1 but only limited variants associated with acquired CNAs. We identified seven regions of deletion, nine of gain, three of chromothripsis (CT) and two of templated-insertion (TI), which contain a number of potential drivers. An additional mechanism involving hypomethylation of genes at 1q may contribute to the aberrant gene expression of a number of genes. Expression changes associated with whole-arm gains were substantial and gene set enrichment analysis identified metabolic processes, apoptotic resistance, signaling via the MAPK pathway, and upregulation of transcription factors as being key drivers of the adverse prognosis associated with these variants. CONCLUSIONS:Multiple layers of genetic complexity impact the phenotype associated with CNAs on chr1 to generate its associated clinical phenotype. Whole-arm gains of 1q are the critically important prognostic group that deregulate multiple pathways, which may offer therapeutic vulnerabilities.

Numerous hemoglobin (Hb) gene mutations have been identified, leading to a spectrum of phenotypes ranging from asymptomatic carrier states to complicated hemolytic anemias. We report a rare case of asymptomatic hypoxemia in a father and his teenage daughter both of whom were found to be carriers of Hb gene variant Zara. Workup for alternative cardiovascular causes of hypoxemia was unremarkable. Further sequencing of the alpha globin locus showed both individuals to be heterozygous for the Hb Zara c.274C>A (p.Leu92Ile) variant of unknown significance in the alpha2-globin gene. This is the first documented association of this Hb variant with familial asymptomatic hypoxemia, highlighting the importance of evaluating for hemoglobinopathies in patients with reduced oxygen saturation.

Background: Tremendous therapeutic progress has been made over the past decade in the field of multiple myeloma (MM). Although the incidence of MM is twice as high for black compared to white individuals, mortality rates remain higher for black patients (Marinac, et al. Blood Ca J 2020). In addition, black Americans are significantly less likely to participate in clinical trials in general (Hong, et al. Am J Prev Med 2021), leading to disproportionate enrollment in studies of novel agents. Various factors may account for these disparities, including access to clinical trials, clinician bias, and hesitancy to enroll in clinical trials among different patient populations. Furthermore, underrepresentation of racial groups within clinical trials impacts the generalizability of important findings from these studies. Here we characterized the racial representation of MM clinical trials.
Method(s): Randomized clinical trials focused on MM interventions published between 2012-2022 were included. We screened 431 publications during this period and characterized racial demographics as available in the literature. A twosided Cochran-Armitage Trend Test was used to assess if there was a linear trend in the percentage of black participants in clinical trials over time.
Result(s): Among 431 studies published over the past 10 years, 76 collected over past 5 years that included racial demographic details were included. Among the 38,830 participants, 87.5% were white, 4.8% were black, and 7.7% were other (reported as either Asian, mixed, or other). There was a significant trend toward increased enrollment comparing over time between 2018 to 2021 (2.1 to 7.0%, p < 0.001 for trend), however black individual remained largely underrepresented in all these studies.
Conclusion(s): While the number of black participating in randomized controlled trials involving MM patients over the past five years is significantly increasing, these studies included a disproportionate number of white participants, despite the incidence of MM being higher for black patients. Efforts are underway in the field to enhance enrollment of underrepresented populations, including a recent randomized study that included 19% black MM patients (Richardson, et al. New Eng J Med 2022). Our study was limited due to many trials not reporting details about racial demographics until relatively recently. Further investigations required to examine the reasons underlying racial disparities in MM trial recruitment and enrollment