Citations

Abstract Aims Mitral valve prolapse (MVP) is a common valvular heart disease with a prevalence of >2% in the general adult population. Despite this high incidence, there is a limited understanding of the molecular mechanism of this disease, and no medical therapy is available for this disease. We aimed to elucidate the genetic basis of MVP in order to better understand this complex disorder. Methods and results We performed a meta-analysis of six genome-wide association studies that included 4884 cases and 434 649 controls. We identified 14 loci associated with MVP in our primary analysis and 2 additional loci associated with a subset of the samples that additionally underwent mitral valve surgery. Integration of epigenetic, transcriptional, and proteomic data identified candidate MVP genes including LMCD1, SPTBN1, LTBP2, TGFB2, NMB, and ALPK3. We created a polygenic risk score (PRS) for MVP and showed an improved MVP risk prediction beyond age, sex, and clinical risk factors. Conclusion We identified 14 genetic loci that are associated with MVP. Multiple analyses identified candidate genes including two transforming growth factor-β signalling molecules and spectrin β. We present the first PRS for MVP that could eventually aid risk stratification of patients for MVP screening in a clinical setting. These findings advance our understanding of this common valvular heart disease and may reveal novel therapeutic targets for intervention.

Abstract The goal of therapy for patients with essential thrombocythemia (ET) and polycythemia vera (PV) is to reduce thrombotic events by normalizing blood counts. Hydroxyurea (HU) and interferon-α (IFN-α) are the most frequently used cytoreductive options for patients with ET and PV at high risk for vascular complications. Myeloproliferative Disorders Research Consortium 112 was an investigator-initiated, phase 3 trial comparing HU to pegylated IFN-α (PEG) in treatment-naïve, high-risk patients with ET/PV. The primary endpoint was complete response (CR) rate at 12 months. A total of 168 patients were treated for a median of 81.0 weeks. CR for HU was 37% and 35% for PEG (P = .80) at 12 months. At 24 to 36 months, CR was 20% to 17% for HU and 29% to 33% for PEG. PEG led to a greater reduction in JAK2V617F at 24 months, but histopathologic responses were more frequent with HU. Thrombotic events and disease progression were infrequent in both arms, whereas grade 3/4 adverse events were more frequent with PEG (46% vs 28%). At 12 months of treatment, there was no significant difference in CR rates between HU and PEG. This study indicates that PEG and HU are both effective treatments for PV and ET. With longer treatment, PEG was more effective in normalizing blood counts and reducing driver mutation burden, whereas HU produced more histopathologic responses. Despite these differences, both agents did not differ in limiting thrombotic events and disease progression in high-risk patients with ET/PV. This trial was registered at www.clinicaltrials.gov as #NCT01259856.

Background High-impact pathogenic variants in more than a thousand genes are involved in Mendelian forms of neurodevelopmental disorders (NDD). Methods This study describes the molecular and clinical characterisation of 28 probands with NDD harbouring heterozygous AGO1 coding variants, occurring de novo for all those whose transmission could have been verified (26/28). Results A total of 15 unique variants leading to amino acid changes or deletions were identified: 12 missense variants, two in-frame deletions of one codon, and one canonical splice variant leading to a deletion of two amino acid residues. Recurrently identified variants were present in several unrelated individuals: p.(Phe180del), p.(Leu190Pro), p.(Leu190Arg), p.(Gly199Ser), p.(Val254Ile) and p.(Glu376del). AGO1 encodes the Argonaute 1 protein, which functions in gene-silencing pathways mediated by small non-coding RNAs. Three-dimensional protein structure predictions suggest that these variants might alter the flexibility of the AGO1 linker domains, which likely would impair its function in mRNA processing. Affected individuals present with intellectual disability of varying severity, as well as speech and motor delay, autistic behaviour and additional behavioural manifestations. Conclusion Our study establishes that de novo coding variants in AGO1 are involved in a novel monogenic form of NDD, highly similar to the recently reported AGO2 -related NDD.

Abstract Background: Splenomegaly is a marker of disease progression in MF; larger spleen size (SS) is correlated with poorer survival and debilitating MF symptoms. In a retrospective real-world study of 408 patients (pts) with MF treated with ruxolitinib (RUX), pts with SS ≥ 10 cm below the left costal margin (LCM) were significantly less likely to attain a spleen response than pts with SS < 10 cm (Palandri 2017); this finding has not been reported in clinical trials of RUX. FEDR is a JAK2-selective inhibitor approved in the US, EU, Canada, and elsewhere as first-line (1L) MF treatment (Tx) and in pts previously treated with RUX. FEDR was evaluated as 1L MF Tx in the phase 3, placebo (PBO)-controlled JAKARTA trial, and in the phase 2, single-arm JAKARTA2 trial in pts previously treated with RUX. Pts allocated to FEDR 400 mg/day (d) in these trials reported substantial reductions from baseline (BL) in spleen volume and MF symptom severity after 6 FEDR Tx cycles. It is important to determine whether spleen volume and symptom improvements during FEDR Tx are influenced by degree of pre-Tx splenomegaly. Objective: Investigate the clinical efficacy of FEDR 400 mg/d in pts in JAKARTA & JAKARTA2 with large spleens at BL. Methods: The JAKARTA trial assessed FEDR 400 mg/d, FEDR 500 mg/d, and placebo in pts with JAK-inhibitor-naïve MF, and the JAKARTA2 trial evaluated FEDR 400 mg/d (starting dose) in pts resistant/intolerant to prior RUX. Both studies enrolled pts with intermediate- or high-risk MF, SS > 5 cm from LCM by palpation, platelets ≥ 50 ×10 9/L, and ECOG PS ≤ 2. These analyses include pts in each trial allocated to receive FEDR 400 mg/d in continuous 28d Tx cycles. Too few pts had BL SS < 10 cm by palpation in JAKARTA (n = 21) and JAKARTA2 (n = 12) for meaningful comparison vs SS ≥ 10 cm. Thus, in these post hoc analyses we divided pts according to the median SS (mSS) at BL in each study , and assessed changes from BL in spleen volume and MFSAF total symptom score (TSS) at the end of cycle 6 (EOC6). Spleen volume was assessed by MRI/CT scan; MFSAF TSS was the sum of 6 MF symptom scores: night sweats, early satiety, pruritus, pain under ribs-left side, abdominal discomfort, and bone/muscle pain. Pts must have had spleen volume and/or TSS data at BL and EOC6. R esults: In JAKARTA, 96 pts were randomized to FEDR 400 mg/d; mSS at BL for all pts was 16 cm (range 5-40). Median (range) BL spleen volume was 1771 (316-3396) mL in the < mSS cohort and 3329 (983-6430) mL in the ≥ mSS cohort; median TSS was 13.0 and 17.6, respectively. Spleen volume data were available at BL and EOC6 for 37 (82%) and 38 (75%) pts in the < mSS and ≥ mSS cohorts, respectively. Median spleen volume reduction (SVR) at EOC6 was -38% [95%CI -43%, -31%] in the < mSS group and -40% [-40%, -28%] in the ≥ mSS group (Figure). Changes in MF symptom scores at EOC6 were similar in the < mSS (n = 37) and ≥ mSS (n = 34) cohorts, with median TSS reductions of -49% and -51%, respectively. For individual symptoms, median reductions in abdominal discomfort, bone/muscle pain, and early satiety were similar between BL SS cohorts, whereas changes were greater in the < mSS group for pruritus and pain under ribs-left side, and greater in the ≥ mSS group for night sweats. In JAKARTA2, 97 pts received FEDR 400 mg/d (starting dose); BL mSS for all pts was 18 cm (range 5-36). Median (range) BL spleen volumes were 1937 (737-4305) and 4002 (1821-7815) mL for pts with < mSS and ≥ mSS, respectively; and BL TSS was 17.2 (0.7-48.0) and 23.6 (1.0-44.0). Spleen volume and MFSAF TSS data were available at BL and EOC6 for 41 and 29 pts, respectively, in the < mSS cohort, and for 41 and 22 pts in the ≥ mSS group. At EOC6, median SVR from BL was -35% [95%CI -40%, -29%] for pts with < mSS at BL and -30% [-37%, -17%] for pts with ≥ mSS (Figure). Median TSS changes were -36% and -49% in the < mSS and ≥ mSS cohorts, respectively; pts with ≥ mSS at BL had similar or greater reductions from BL in 5/6 MFSAF symptoms (all except pruritus) vs those with < mSS. Conclusions: These analyses demonstrate that extent of splenomegaly at BL in JAKARTA and JAKARTA2 did not influence the likelihood of achieving improvements in spleen volume or MF symptom severity for pts receiving FEDR 400 mg/d as 1L MF Tx or as post-RUX salvage Tx. For pts who completed 6 FEDR Tx cycles, reductions in spleen volume and TSS at EOC6 in the ≥ mSS cohorts in both studies were similar to those in the < mSS cohorts, even though BL spleen volumes and TSS were higher in the ≥ mSS groups. Figure 1 Figure 1. Disclosures Kiladjian: Incyte Corporation: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Taiho Oncology, Inc.: Research Funding; PharmaEssentia: Other: Personal fees; AOP Orphan: Membership on an entity's Board of Directors or advisory committees; AbbVie: Membership on an entity's Board of Directors or advisory committees. Passamonti: BMS: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; AbbVie: Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Vannucchi: BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees; Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Membership on an entity's Board of Directors or advisory committees. Talpaz: Imago: Consultancy; Celgene: Consultancy; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Constellation: Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Other: Grant/research support . Cervantes: Bristol Myers Squibb: Consultancy, Honoraria. Harrison: Roche: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Constellation Pharmaceuticals: Research Funding; Shire: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead Sciences: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; CTI BioPharma: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Keros: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Incyte Corporation: Speakers Bureau; Sierra Oncology: Honoraria; Promedior: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AOP Orphan Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Galacteo: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Geron: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Abbvie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Mesa: AOP: Consultancy; La Jolla Pharma: Consultancy; Sierra Oncology: Consultancy, Research Funding; Incyte Corporation: Consultancy, Research Funding; Genentech: Research Funding; Samus: Research Funding; CTI: Research Funding; Celgene: Research Funding; Abbvie: Research Funding; Constellation Pharmaceuticals: Consultancy, Research Funding; Novartis: Consultancy; Gilead: Research Funding; CTI: Research Funding; Pharma: Consultancy; Promedior: Research Funding. Mascarenhas: Geron: Consultancy; Merus: Research Funding; Geron: Consultancy, Research Funding; Merck: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Constellation: Consultancy, Membership on an entity's Board of Directors or advisory committees; AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; PharmaEssentia: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Prelude: Consultancy; Galecto: Consultancy; Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Incyte: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; CTI Biopharm: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Forbius: Research Funding; Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees; Promedior: Consultancy, Membership on an entity's Board of Directors or advisory committees; Genentech/Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees; Sierra Oncology: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene/BMS: Consultancy, Membership on an entity's Board of Directors or advisory committees; Kartos: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Verstovsek: Promedior: Research Funding; CTI BioPharma: Research Funding; Blueprint Medicines Corp: Research Funding; Protagonist Therapeutics: Research Funding; Genentech: Research Funding; Ital Pharma: Research Funding; Incyte Corporation: Consultancy, Research Funding; Gilead: Research Funding; NS Pharma: Research Funding; PharmaEssentia: Research Funding; Celgene: Consultancy, Research Funding; Roche: Research Funding; AstraZeneca: Research Funding; Novartis: Consultancy, Research Funding; Sierra Oncology: Consultancy, Research Funding; Constellation: Consultancy; Pragmatist: Consultancy. Devos: Alexion, AstraZeneca Rare Disease Inc.: Consultancy; Incyte: Consultancy; AbbVie: Consultancy; Bristol Myers Squibb - Celegene: Consultancy; Novartis: Consultancy. Rose: Bristol Myers Squibb: Current Employment, Current equity holder in publicly-traded company, Current holder of individual stocks in a privately-held company, Current holder of stock options in a privately-held company. Zhang: Bristol Myers Squibb: Current Employment. Sy: Bristol Myers Squibb: Current Employment.

Abstract Introduction: Thrombocytopenia, a hallmark of cytopenic myelofibrosis (MF), is associated with poor survival and quality of life impairment. Patients with MF and moderate or severe thrombocytopenia (platelet counts <100x10 9/L, <50x10 9/L) tend to have high symptom burden as measured by the Total Symptom Score (TSS), driven largely by physical functioning symptoms (Mesa R et al, ASH 2021 abstract in submission). Pacritinib, an investigational JAK2/IRAK1 inhibitor, was studied in patients with platelet counts ≤100x10 9/L in the PERSIST-2 trial. Unlike the pivotal studies upon which available JAK1/2 inhibitors were approved that relied on a modified TSS version that excluded 'tiredness' from the response analysis, PERSIST-2 included 'tiredness' as part of TSS and found response rates of 25% for pacritinib vs. 14% for best available therapy (BAT), P=0.08. Here, we retrospectively analyzed TSS on PERSIST-2 using the modified scoring system. In addition, we evaluated the impact of pacritinib and BAT, including ruxolitinib, on MF symptoms including 'tiredness' and 'inactivity'. Methods: All PERSIST-2 patients in the intention-to-treat population randomized at least 22 weeks prior to the end of the study were included. PERSIST-2 randomized patients 1:1:1 to pacritinib 200mg BID, pacritinib 400mg daily, or BAT (including ruxolitinib). The modified TSS score was calculated as the sum of individual symptom scores for early satiety, abdominal discomfort, rib pain, night sweats, itching, and bone pain ('tiredness' and 'inactivity' were not included), and response was defined as a ≥50% reduction in score from baseline to week 24. Symptoms were categorized as physical function-related (tiredness, inactivity), spleen-related (satiety, abdominal discomfort, rib pain), or cytokine-related (sweats, itching, bone pain). The Wilcoxon Rank Sum test was used to compare differences in scores. Results: The analysis included 74 patients randomized to pacritinib 200mg BID and 72 to BAT; an additional 75 were randomized to pacritinib 400mg QD (dose no longer in development). At baseline, 39% had moderate and 46% had severe thrombocytopenia. Ruxolitinib was selected as BAT in 45% of patients with moderate and 38% with severe thrombocytopenia. The co-primary endpoint for the study - TSS response rate in pooled pacritinib arms versus BAT - showed a significant difference using the modified TSS: 30% vs. 14%, P=0.008. Similarly, the modified TSS response rate was higher for patients treated with pacritinib 200mg BID compared to BAT (35% vs. 14%, P=0.004, Figure 1a). Among patients on the BAT arm, modified TSS response rates were modestly higher for patients who received ruxolitinib prior to week 24 (19% [n=6/32]) compared to those who did not (10% [n=4/40]), though both were lower than response rates with pacritinib. Patients on the pacritinib 200mg BID arm experienced greater percentage reductions in individual myelofibrosis symptoms between baseline and week 24 compared to BAT, both in patients with moderate and severe thrombocytopenia (Figure 1b, 1c). For physical function symptoms, severity was reduced more on pacritinib 200mg BID compared to BAT by week 24 (median reduction in tiredness: 30% vs. 13%, P=0.0261; inactivity: 22% vs. 7%, P=0.099). Among patients with severe thrombocytopenia, symptom improvement was minimal on BAT (Figure 1b). Conclusion: The symptom benefit of pacritinib in patients with moderate and severe thrombocytopenia is demonstrated in the PERSIST-2 study. A significant reduction in symptoms was observed in patients treated with pacritinib 200mg BID, the dose being studied in an ongoing Phase 3 trial (PACIFICA), compared to BAT. Furthermore, the modified TSS response rate of 35% in patients treated with pacritinib 200mg BID is comparable to that reported for approved JAK1/2 inhibitors in patients with higher platelet counts, suggesting the potential for pacritinib to address the unmet need of patients with cytopenic myelofibrosis. Figure 1 Figure 1. Disclosures Palmer: CTI BioPharma: Consultancy, Research Funding; Protagonist: Consultancy, Research Funding; Incyte: Research Funding; PharmaEssentia: Research Funding; Sierra Oncology: Consultancy, Research Funding. Mesa: Incyte Corporation: Consultancy, Research Funding; Samus: Research Funding; Sierra Oncology: Consultancy, Research Funding; CTI: Research Funding; Novartis: Consultancy; Celgene: Research Funding; Pharma: Consultancy; La Jolla Pharma: Consultancy; Constellation Pharmaceuticals: Consultancy, Research Funding; CTI: Research Funding; Abbvie: Research Funding; Gilead: Research Funding; Genentech: Research Funding; Promedior: Research Funding; AOP: Consultancy. Oh: Abbvie: Membership on an entity's Board of Directors or advisory committees; Blueprint Medicines: Membership on an entity's Board of Directors or advisory committees; Celgene Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Constellation: Membership on an entity's Board of Directors or advisory committees; CTI Biopharma: Membership on an entity's Board of Directors or advisory committees; Disc Medicine: Membership on an entity's Board of Directors or advisory committees; Geron: Membership on an entity's Board of Directors or advisory committees; Incyte: Membership on an entity's Board of Directors or advisory committees; Kartos Therapeutics: Membership on an entity's Board of Directors or advisory committees; PharamaEssentia: Membership on an entity's Board of Directors or advisory committees; Sierra Oncology: Membership on an entity's Board of Directors or advisory committees. Rampal: Sierra Oncology: Consultancy; Novartis: Consultancy; BMS/Celgene: Consultancy; Stemline: Consultancy, Research Funding; Jazz Pharmaceuticals: Consultancy; Constellation: Research Funding; Kartos: Consultancy; Disc Medicine: Consultancy; Blueprint: Consultancy; Pharmaessentia: Consultancy; Incyte: Consultancy, Research Funding; Memorial Sloan Kettering: Current Employment; Abbvie: Consultancy; CTI: Consultancy. Buckley: CTI Biopharm: Current Employment. Roman-Torres: CTI Biopharm: Current Employment. Verstovsek: Protagonist Therapeutics: Research Funding; Genentech: Research Funding; Gilead: Research Funding; Incyte Corporation: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; NS Pharma: Research Funding; AstraZeneca: Research Funding; Blueprint Medicines Corp: Research Funding; CTI BioPharma: Research Funding; Promedior: Research Funding; Ital Pharma: Research Funding; PharmaEssentia: Research Funding; Roche: Research Funding; Novartis: Consultancy, Research Funding; Sierra Oncology: Consultancy, Research Funding; Constellation: Consultancy; Pragmatist: Consultancy. Mascarenhas: Sierra Oncology: Consultancy, Membership on an entity's Board of Directors or advisory committees; Merck: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Merus: Research Funding; Geron: Consultancy; Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees; PharmaEssentia: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Forbius: Research Funding; Genentech/Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Geron: Consultancy, Research Funding; Constellation: Consultancy, Membership on an entity's Board of Directors or advisory committees; Promedior: Consultancy, Membership on an entity's Board of Directors or advisory committees; Kartos: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene/BMS: Consultancy, Membership on an entity's Board of Directors or advisory committees; Incyte: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Prelude: Consultancy; Galecto: Consultancy; CTI Biopharm: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Vannucchi: AbbVie: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees; Incyte Corporation: Honoraria, Membership on an entity's Board of Directors or advisory committees. Kiladjian: CTI BioPharma: Membership on an entity's Board of Directors or advisory committees, Research Funding; AP Orphan: Membership on an entity's Board of Directors or advisory committees; Incyte: Membership on an entity's Board of Directors or advisory committees; AbbVie: Membership on an entity's Board of Directors or advisory committees; Celgene/BMS: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; PharmaEssentia: Membership on an entity's Board of Directors or advisory committees. Harrison: Galacteo: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Promedior: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Constellation Pharmaceuticals: Research Funding; Incyte Corporation: Speakers Bureau; Roche: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Keros: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Shire: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Abbvie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AOP Orphan Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sierra Oncology: Honoraria; Gilead Sciences: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Geron: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; CTI BioPharma: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Bose: Novartis: Honoraria; NS Pharma: Research Funding; Pfizer: Research Funding; Constellation Pharmaceuticals: Research Funding; Blueprint Medicines: Honoraria, Research Funding; Kartos Therapeutics: Honoraria, Research Funding; Incyte Corporation: Honoraria, Research Funding; Promedior: Research Funding; CTI BioPharma: Honoraria, Research Funding; Sierra Oncology: Honoraria; Astellas: Research Funding; BMS: Honoraria, Research Funding; Celgene Corporation: Honoraria, Research Funding. Craig: CTI BioPharma: Current Employment. Gerds: PharmaEssentia Corporation: Consultancy; CTI BioPharma: Research Funding; Sierra Oncology: Consultancy; AbbVie: Consultancy; Celgene/Bristol Myers Squibb: Consultancy; Constellation: Consultancy; Novartis: Consultancy.

Abstract Introduction: Multiple myeloma (MM) is a chronic hematologic malignancy with a high symptom burden that can have a substantial negative impact on patients' (pts) health-related quality of life (HRQoL). The introduction of novel triplet regimens for newly diagnosed MM (NDMM) has extended progression-free survival (PFS) and overall survival (OS); however, adverse events and demanding administration and monitoring schedules have a further negative effect on HRQoL, especially among pts who are transplant ineligible (TIE) due to older age and/or frailty. Optimizing initial treatment is particularly important in older pts, many of whom receive only 1 line of therapy. The phase 3 MAIA trial compared daratumumab, lenalidomide, and dexamethasone (D-Rd) vs lenalidomide and dexamethasone (Rd) in TIE pts with NDMM. At a median follow-up of 28 months, D-Rd significantly prolonged PFS and was associated with faster and sustained clinically meaningful improvements in patient-reported outcomes (PROs) vs Rd. Results of an updated analysis with longer follow-up recently confirmed a significant benefit in OS with D-Rd vs Rd as well as a continued significant PFS benefit and higher rates of complete response or better and very good partial response or better. Here we present an update of the HRQoL analysis with additional follow-up. Methods: MAIA (NCT02252172) is a randomized, open-label, active controlled, multicenter, phase 3 study of TIE pts with NDMM who were randomly assigned 1:1 to receive D-Rd or Rd until disease progression (PD) or unacceptable toxicity. PROs were recorded using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30-item (EORTC QLQ-C30) and the EQ-5D-5L visual analog scale. EORTC QLQ-C30 has 30 items comprising 5 functional scales (physical, role, emotional, cognitive, and social functioning), 1 global health status (GHS) scale, 3 symptom scales (fatigue, nausea and vomiting, and pain) and 6 single items (dyspnea, insomnia, appetite loss, constipation, diarrhea, and financial difficulties). Questionnaires were completed at baseline, on day 1 of cycles 3, 6, 9, and 12 for year 1, and every 6 months thereafter until PD. Analyses were conducted on all pts with a baseline and ≥1 post-baseline PRO assessment. Pts were censored at PD or discontinuation of study treatment. Thresholds for meaningful improvement and worsening were defined a priori based on published literature (≥10-point change). Treatment effect was analyzed using a mixed-effects model for repeated measurements including baseline value, visit, treatment, visit by treatment interaction, and randomization stratification factors as fixed effects and individual subject as random effect. Results: At a median follow-up of 56.2 months, discontinuation rates were lower with D-Rd than Rd (56.8% vs 80.8%). For GHS, physical functioning, fatigue, pain, and dyspnea, PROs that are particularly relevant to pts with MM, a numerically greater proportion of pts achieved a meaningful improvement with D-Rd vs Rd (Table 1). Differences were significant for physical functioning, fatigue, and dyspnea. The proportion of pts achieving a meaningful worsening on therapy was similar in both treatment groups (Table 1). The median time to improvement was numerically shorter with D-Rd vs Rd for physical functioning and pain and with Rd vs D-Rd for GHS and fatigue; differences were not significant (Table 2). The median time to worsening of fatigue was similar between groups, numerically longer for D-Rd vs Rd for GHS, and significantly longer with D-Rd than Rd for physical functioning, pain, and dyspnea (Table 2). Median time to worsening of pain with D-Rd vs Rd was 39.43 vs 17.97 months, reflective of an additional ~21 months without worsening pain among pts treated with D-Rd. Between-group differences for least squares mean change from baseline for these 5 PROs favored D-Rd vs Rd at all assessment time points except cycle 3 for physical functioning and cycle 6 for fatigue; differences were significant at ≥1 timepoint for each scale. Conclusions: These updated PRO analyses from the MAIA study demonstrate sustained and clinically meaningful improvements in HRQoL with D-Rd vs Rd with almost 5 years of follow-up. These results are consistent with the clinical benefits of superior PFS, OS, and deep responses observed with D-Rd compared with Rd and support the use of D-Rd in older pts. Figure 1 Figure 1. Disclosures Perrot: Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene/BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Honoraria; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Honoraria; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Kumar: Roche-Genentech: Consultancy, Research Funding; Novartis: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Research Funding; Bluebird Bio: Consultancy; Tenebio: Research Funding; Adaptive: Membership on an entity's Board of Directors or advisory committees, Research Funding; Astra-Zeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Carsgen: Research Funding; KITE: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Merck: Research Funding; Antengene: Consultancy, Honoraria; Oncopeptides: Consultancy; Beigene: Consultancy; BMS: Consultancy, Research Funding; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Research Funding; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Plesner: Takeda: Research Funding; Oncopeptides: Other: Advisor, Research Funding; Genentech: Other: Advisor, Research Funding; CSL Behring: Other: Advisor; AbbVie: Other: Advisor, Research Funding; Celgene: Other: Advisor, Research Funding; Janssen: Other: Advisor, Research Funding; Genmab: Research Funding. Orlowski: Amgen, Inc., BioTheryX, Inc., Bristol-Myers Squibb, Celgene, EcoR1 Capital LLC, Genzyme, GSK Biologicals, Janssen Biotech, Karyopharm Therapeutics, Inc., Neoleukin Corporation, Oncopeptides AB, Regeneron Pharmaceuticals, Inc., Sanofi-Aventis, and Takeda P: Consultancy, Honoraria; CARsgen Therapeutics, Celgene, Exelixis, Janssen Biotech, Sanofi-Aventis, Takeda Pharmaceuticals North America, Inc.: Other: Clinical research funding; Asylia Therapeutics, Inc., BioTheryX, Inc., and Heidelberg Pharma, AG.: Other: Laboratory research funding; Asylia Therapeutics, Inc.: Current holder of individual stocks in a privately-held company, Patents & Royalties; Amgen, Inc., BioTheryX, Inc., Bristol-Myers Squibb, Celgene, Forma Therapeutics, Genzyme, GSK Biologicals, Janssen Biotech, Juno Therapeutics, Karyopharm Therapeutics, Inc., Kite Pharma, Neoleukin Corporation, Oncopeptides AB, Regeneron Pharmaceuticals, I: Membership on an entity's Board of Directors or advisory committees. Moreau: Oncopeptides: Honoraria; Sanofi: Honoraria; Janssen: Honoraria; Celgene BMS: Honoraria; Amgen: Honoraria; Abbvie: Honoraria. Bahlis: BMS/Celgene: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; Genentech: Consultancy; GlaxoSmithKline: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Karyopharm: Consultancy, Honoraria. Nahi: XNK Therapeutics AB: Consultancy. Hulin: Takeda: Honoraria; Sanofi: Honoraria; Celgene/BMS: Honoraria; Janssen: Honoraria; abbvie: Honoraria. Quach: CSL: Consultancy, Membership on an entity's Board of Directors or advisory committees; Antengene: Consultancy, Membership on an entity's Board of Directors or advisory committees; GlaxoSmithKline: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol Myers Squibb: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Karyopharm: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen/Cilag: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees. Goldschmidt: Chugai: Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; BMS: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Incyte: Research Funding; Janssen: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Johns Hopkins University: Other: Grant; Molecular Partners: Research Funding; MSD: Research Funding; Mundipharma: Research Funding; Sanofi: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Takeda: Consultancy, Research Funding; Adaptive Biotechnology: Consultancy; Celgene: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Novartis: Honoraria, Research Funding; Dietmar-Hopp-Foundation: Other: Grant; GSK: Honoraria; Amgen: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding. O'Dwyer: ONK Therapeutics: Current Employment, Current equity holder in publicly-traded company, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy; Bristol Myers Squibb: Research Funding. Venner: BMS: Honoraria; Amgen: Research Funding; Celgene: Research Funding; Amgen: Honoraria; Takeda: Honoraria; Janssen: Honoraria; Sanofi: Honoraria; Pfizer: Honoraria. Weisel: Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol Myers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Adaptive Biotechnologies: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Honoraria; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Karyopharm: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Consultancy; Novartis: Honoraria; Pfizer: Honoraria. Raje: Celgene, Amgen, Bluebird Bio, Janssen, Caribou, and BMS: Other. Macro: Sanofi: Honoraria; GSK: Honoraria; Takeda: Honoraria, Other: Travel accomodation, Research Funding; Janssen: Honoraria, Other: Travel accomodation, Research Funding; Celgen/BMS: Honoraria. Leleu: Sanofi: Honoraria; Takeda: Honoraria, Other: Non-financial support; Janssen-Cilag: Honoraria; Karyopharm Therapeutics: Honoraria; Merck: Honoraria; Mundipharma: Honoraria; Novartis: Honoraria; Oncopeptides: Honoraria; Gilead Sciences: Honoraria; Celgene: Honoraria; Carsgen Therapeutics Ltd: Honoraria; Bristol-Myers Squibb: Honoraria; Amgen: Honoraria; AbbVie: Honoraria; Pierre Fabre: Honoraria; Roche: Honoraria. Liu: Janssen: Current Employment, Current equity holder in publicly-traded company. Fastenau: Janssen: Current Employment, Current equity holder in publicly-traded company. Gries: Janssen: Current Employment, Current holder of individual stocks in a privately-held company. Ho: DRG Abacus: Consultancy; Janssen: Consultancy; Emalex Biosciences: Consultancy. Mistry: Janssen: Current Employment, Current equity holder in publicly-traded company. Tromp: Janssen: Current Employment, Current equity holder in publicly-traded company. Delioukina: Janssen: Current Employment. Vermeulen: Janssen: Current Employment, Current equity holder in publicly-traded company. Usmani: Abbvie: Consultancy; Array BioPharma: Consultancy, Research Funding; Celgene/BMS: Consultancy, Research Funding, Speakers Bureau; GSK: Consultancy, Research Funding; EdoPharma: Consultancy; Janssen: Consultancy, Research Funding, Speakers Bureau; Sanofi: Consultancy, Research Funding, Speakers Bureau; Merck: Consultancy, Research Funding; Pharmacyclics: Consultancy, Research Funding; Seattle Genetics: Consultancy, Research Funding; SkylineDX: Consultancy, Research Funding; Takeda: Consultancy, Research Funding, Speakers Bureau; Janssen Oncology: Consultancy, Research Funding; Bristol-Myers Squibb: Research Funding; Amgen: Consultancy, Research Funding, Speakers Bureau.

Abstract Introduction: The phase 3 MAIA study (NCT02252172) evaluated the addition of daratumumab (D) to lenalidomide and dexamethasone (Rd) in patients (pts) with transplant-ineligible newly diagnosed multiple myeloma (NDMM). At a median follow-up of 56.2 months, D-Rd prolonged progression-free survival (PFS) and overall survival (OS) versus Rd alone, despite almost half of the pts in the Rd arm who received subsequent therapy receiving a daratumumab-containing regimen as any subsequent line of therapy (Facon T, et al. Presented at: European Hematology Association 2021 Virtual Congress. Abstract LB1901). Approximately 20% to 50% of pts with MM have baseline renal impairment that can affect the choice and efficacy of therapy (Dimopoulos MA, et al. Journal of Clinical Oncology. 2016;34[13]:1544-1557). Here, we report results from MAIA for D-Rd vs Rd in pts with impaired renal function based on lenalidomide starting dose at a median follow-up of 56.2 months. Methods: Pts with NDMM ineligible for high-dose chemotherapy and autologous stem-cell transplantation due to age ≥65 years or comorbidities were randomized 1:1 to receive D-Rd or Rd. Pts in both arms received 28-day cycles of oral Rd (R: 25 mg [10 mg recommended if creatinine clearance (CrCl) was 30-50 mL/min] on Days 1-21; d: 40 mg [20 mg if aged >75 years or body-mass index <18.5 kg/m 2] on Days 1, 8, 15, 22). Pts in the D-Rd arm also received intravenous D (16 mg/kg once weekly for Cycles 1-2, once every 2 weeks for Cycles 3-6, and once every 4 weeks thereafter). Pts in both arms were treated until disease progression or unacceptable safety events. The primary endpoint was PFS, and a secondary endpoint was OS. Renal impairment was defined as a baseline CrCl of ≤60 mL/min. Results: 737 pts were randomized (D-Rd, n=368; Rd, n=369); 162 (44%) pts in the D-Rd arm and 142 (38%) pts in the Rd arm had renal impairment as defined. At a median follow-up of 56.2 months, in pts with renal impairment who received a lenalidomide starting dose of 25 mg (25 mg subgroup; D-Rd, n=60 [37%]; Rd, n=62 [44%]), a PFS and OS advantage was observed with D-Rd versus Rd (Table). In pts with renal impairment who received a lenalidomide starting dose of <25 mg (<25 mg subgroup; D-Rd, n=98 [60%]; Rd, n=75 [53%]), median PFS and OS were prolonged with D-Rd versus Rd (Table). Among pts in the 25 mg subgroup who died (D-Rd, n=12; Rd, n=29), disease progression was the primary cause of death in 6 (50%) pts in the D-Rd arm and 10 (34%) pts in the Rd arm. Among pts in the <25 mg subgroup who died (D-Rd, n=44; Rd, n=37), disease progression was the primary cause of death in 16 (36%) pts in the D-Rd arm and 11 (30%) pts in the Rd arm. Conclusion: After ~5 years of follow-up, D-Rd showed a PFS improvement versus Rd in transplant-ineligible pts with NDMM and renal impairment regardless of lenalidomide starting dose. An OS advantage for D-Rd versus Rd was observed in pts with renal impairment who received a lenalidomide starting dose of 25 mg; in pts with renal impairment who received a lenalidomide starting dose of <25 mg, median OS was prolonged for D-Rd versus Rd, but the OS benefit was less pronounced. Overall, among pts with renal impairment, PFS and OS benefits of D-Rd versus Rd were observed regardless of lenalidomide starting dose; however, dose recommendations per the lenalidomide prescribing information should be followed. Many transplant-ineligible pts with NDMM may not receive a second line of therapy; our results support the frontline use of D-Rd to provide prolonged disease control in transplant-ineligible pts with NDMM and renal impairment. Figure 1 Figure 1. Disclosures Usmani: Abbvie: Consultancy; Array BioPharma: Consultancy, Research Funding; Celgene/BMS: Consultancy, Research Funding, Speakers Bureau; GSK: Consultancy, Research Funding; EdoPharma: Consultancy; Janssen: Consultancy, Research Funding, Speakers Bureau; Sanofi: Consultancy, Research Funding, Speakers Bureau; Merck: Consultancy, Research Funding; Pharmacyclics: Consultancy, Research Funding; Seattle Genetics: Consultancy, Research Funding; SkylineDX: Consultancy, Research Funding; Takeda: Consultancy, Research Funding, Speakers Bureau; Janssen Oncology: Consultancy, Research Funding; Bristol-Myers Squibb: Research Funding; Amgen: Consultancy, Research Funding, Speakers Bureau. Kumar: Novartis: Research Funding; KITE: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Research Funding; Merck: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Astra-Zeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Beigene: Consultancy; Antengene: Consultancy, Honoraria; BMS: Consultancy, Research Funding; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Carsgen: Research Funding; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Tenebio: Research Funding; Oncopeptides: Consultancy; Bluebird Bio: Consultancy; Roche-Genentech: Consultancy, Research Funding; Adaptive: Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Research Funding. Plesner: CSL Behring: Other: Advisor; Genentech: Other: Advisor, Research Funding; Oncopeptides: Other: Advisor, Research Funding; Takeda: Research Funding; Celgene: Other: Advisor, Research Funding; AbbVie: Other: Advisor, Research Funding; Janssen: Other: Advisor, Research Funding; Genmab: Research Funding. Orlowski: Amgen, Inc., BioTheryX, Inc., Bristol-Myers Squibb, Celgene, EcoR1 Capital LLC, Genzyme, GSK Biologicals, Janssen Biotech, Karyopharm Therapeutics, Inc., Neoleukin Corporation, Oncopeptides AB, Regeneron Pharmaceuticals, Inc., Sanofi-Aventis, and Takeda P: Consultancy, Honoraria; CARsgen Therapeutics, Celgene, Exelixis, Janssen Biotech, Sanofi-Aventis, Takeda Pharmaceuticals North America, Inc.: Other: Clinical research funding; Asylia Therapeutics, Inc., BioTheryX, Inc., and Heidelberg Pharma, AG.: Other: Laboratory research funding; Asylia Therapeutics, Inc.: Current holder of individual stocks in a privately-held company, Patents & Royalties; Amgen, Inc., BioTheryX, Inc., Bristol-Myers Squibb, Celgene, Forma Therapeutics, Genzyme, GSK Biologicals, Janssen Biotech, Juno Therapeutics, Karyopharm Therapeutics, Inc., Kite Pharma, Neoleukin Corporation, Oncopeptides AB, Regeneron Pharmaceuticals, I: Membership on an entity's Board of Directors or advisory committees. Moreau: Abbvie: Honoraria; Amgen: Honoraria; Janssen: Honoraria; Sanofi: Honoraria; Celgene BMS: Honoraria; Oncopeptides: Honoraria. Bahlis: Janssen: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; GlaxoSmithKline: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; BMS/Celgene: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria; Genentech: Consultancy; Amgen: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; Karyopharm: Consultancy, Honoraria. Nahi: XNK Therapeutics AB: Consultancy. Hulin: Janssen: Honoraria; Celgene/BMS: Honoraria; Sanofi: Honoraria; Takeda: Honoraria; abbvie: Honoraria. Quach: GlaxoSmithKline: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen/Cilag: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; CSL: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees; Antengene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Karyopharm: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Goldschmidt: Takeda: Consultancy, Research Funding; Sanofi: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Novartis: Honoraria, Research Funding; Dietmar-Hopp-Foundation: Other: Grant; Mundipharma: Research Funding; MSD: Research Funding; Molecular Partners: Research Funding; Johns Hopkins University: Other: Grant; Janssen: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Celgene: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; BMS: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Chugai: Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; GSK: Honoraria; Incyte: Research Funding; Adaptive Biotechnology: Consultancy; Amgen: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding. O'Dwyer: ONK Therapeutics: Current Employment, Current equity holder in publicly-traded company, Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Research Funding; Janssen: Consultancy. Perrot: Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Honoraria, Research Funding; GSK: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Honoraria. Venner: Janssen: Honoraria; Amgen: Honoraria; Takeda: Honoraria; Celgene: Research Funding; Pfizer: Honoraria; Sanofi: Honoraria; BMS: Honoraria; Amgen: Research Funding. Weisel: Novartis: Honoraria; Adaptive Biotechnologies: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Karyopharm: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Oncopeptides: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Consultancy; Roche: Honoraria; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Honoraria. Raje: Celgene, Amgen, Bluebird Bio, Janssen, Caribou, and BMS: Other. Macro: Janssen: Honoraria, Other: Travel accomodation, Research Funding; GSK: Honoraria; Sanofi: Honoraria; Celgen/BMS: Honoraria; Takeda: Honoraria, Other: Travel accomodation, Research Funding. Leleu: Bristol-Myers Squibb: Honoraria; Carsgen Therapeutics Ltd: Honoraria; Celgene: Honoraria; Gilead Sciences: Honoraria; Janssen-Cilag: Honoraria; Karyopharm Therapeutics: Honoraria; Merck: Honoraria; Mundipharma: Honoraria; Novartis: Honoraria; Oncopeptides: Honoraria; Pierre Fabre: Honoraria; Roche: Honoraria; Sanofi: Honoraria; Amgen: Honoraria; AbbVie: Honoraria; Takeda: Honoraria, Other: Non-financial support. Pei: Janssen: Current Employment, Current equity holder in publicly-traded company. Van Rampelbergh: Janssen: Current Employment. Tromp: Janssen: Current Employment, Current equity holder in publicly-traded company. Delioukina: Janssen: Current Employment.

Abstract Multiple myeloma (MM) is an incurable form of plasma cell cancer in which primary and secondary chromosomal translocations routinely juxtapose oncogenes to plasma cell-specific super-enhancers. Coincidentally, drugs which target super-enhancers have had success clinically. For example, immunomodulatory imide drugs (IMiDs) degrade super-enhancer-binding pioneer factors IKAROS and AIOLOS, while glucocorticoids (Dexamethasone) and proteasome inhibitors (Bortezomib) have the ability to transrepress or block the processing of super-enhancer-forming NF-κB proteins, respectively. Currently, alternative enhancer-targeting drugs are also in clinical development, like p300 inhibitors which target the acetyl-binding bromodomains and/or histone acetyl transferase activity of the chromatin-regulating coactivator homologs CBP and EP300. Despite showing therapeutic promise, our understanding of how these drugs function, alone or together, remains incomplete. Case in point, we find that IMiD-induced degradation of its target proteins IKAROS and AIOLOS does not guarantee a therapeutic response in vitro, and patients successfully treated with IMiDs eventually relapse; meanwhile, coactivator-targeting therapies like p300 inhibitors are often too toxic in vivo, and lack a therapeutic window. To improve the outcomes of MM patients we need to understand the heterogeneous genetics and transcription-factor milieus of the myeloma enhancer landscape, as well as how to increase the precision of enhancer-disrupting drugs. To accomplish this, our lab utilizes more than 60 human myeloma cell lines that have been extensively characterized at the genetic, proteomic, and drug-therapeutic-response levels. Additionally, we have generated a highly-predictive immunocompetent mouse model (Vk*MYC hCRBN+) that develops human-like MM and is sensitive to both IMiDs and a new class of therapeutics termed "degronimids" (normal mice do not respond to IMiDs or degronimids). Our central hypothesis is that combining a broad coactivator-targeting drug (e.g., the p300 inhibitor GNE-781), with a MM-specific transcription factor-targeting drug (e.g., IMiDs) restricts toxicities to myeloma cells and thus improves the therapeutic window. Currently, we are testing a variety of coactivator-targeting compounds alongside traditional IMiD therapies and other preclinical transcription factor-targeting drugs both in vivo and in vitro. We show that Vk*MYC hCRBN+ mice are exquisitely sensitive to GNE-781, requiring one fourth of the dose needed to treat other cancers and therefore avoiding the neutropenia and thrombocytopenia seen at higher doses. Second, we show that although IMiDs and GNE-781 induce an effective but transient response in vivo as single agents, the combination of the two drugs proved curative, with a progressive deepening of the anti-tumor response occurring even after therapy is discontinued. Ongoing experiments aim to determine how this drug combination, and other coactivator + transcription factor-targeting combinations, permanently disrupt myeloma-specific super-enhancers. Disclosures Neri: BMS: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Janssen: Consultancy, Honoraria. Bahlis: Sanofi: Consultancy, Honoraria; GlaxoSmithKline: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; BMS/Celgene: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Karyopharm: Consultancy, Honoraria; Genentech: Consultancy. Boise: AstraZeneca: Honoraria, Research Funding; AbbVie/Genentech: Membership on an entity's Board of Directors or advisory committees. Chesi: Abcuro: Patents & Royalties: Genetically engineered mouse model of myeloma; Pi Therapeutics: Patents & Royalties: Genetically engineered mouse model of myeloma; Pfizer: Consultancy; Novartis: Consultancy, Patents & Royalties: human CRBN transgenic mouse; Palleon Pharmaceuticals: Patents & Royalties: Genetically engineered mouse model of myeloma.

Abstract Introduction: Depth of response is associated with long-term outcomes in multiple myeloma (MM); however, the effect of response kinetics on outcomes in NDMM is variable and less clear. Although some studies have shown that achieving a ≥very good partial response (VGPR) at 4 months (mos) from diagnosis is associated with increased overall survival (Garderet Leukemia 2018), other reports have shown worse outcomes in pts with early vs late responses (Yan Blood Adv 2019). The double-blind, randomized TOURMALINE-MM2 (NCT01850524) trial (Facon Blood 2021) showed a clinical meaningful progression-free survival (PFS) benefit with IRd vs pbo-Rd (median 35.3 vs 21.8 mos; hazard ratio, 0.830; 95% confidence interval, 0.676-1.018; P=0.073; median follow-up, 53.3 and 55.8 mos, respectively) in NDMM pts. Safety data were consistent with the established toxicity profile of IRd. We evaluated PFS and duration of response (DOR) by depth of best confirmed response and time to best response in TOURMALINE-MM2. Methods: Pts were randomized to receive oral ixazomib 4 mg (n=351) or placebo (n=354) on days 1, 8, and 15, plus oral lenalidomide 25 mg (10 mg if creatinine clearance ≤60 mL/min) on days 1-21 and oral dexamethasone 40 mg (20 mg in pts aged >75 years) on days 1, 8, 15, and 22 in 28-day cycles. After 18 cycles, treatment was continued without dexamethasone and reduced doses of ixazomib (3 mg) and lenalidomide (10 mg) until progressive disease (PD)/toxicity. Response assessments were performed every cycle until PD, or every 4 weeks in pts who discontinued treatment prior to PD. PFS and DOR were analyzed post-hoc in subgroups defined by depth of response and in subgroups defined by time to best confirmed response; 'early' and 'late' responses were defined by time to best confirmed response of 0-4 and >4 mos, respectively (additional analyses were performed by time to best confirmed response of 0-6 and >6 mos). Pts in either subgroup could have recorded an initial response prior to their best response. PFS and DOR were evaluated from randomization to progression and time of initial response to progression, respectively. To address potential guarantee-time bias in the PFS analysis, and to eliminate potential bias due to transient responses in DOR analysis, sensitivity analyses were conducted in pts with PFS / DOR of ≥6 mos. Results: Among the 705 pts in the intention-to-treat (ITT) population, 20% (26% IRd vs 14% placebo-Rd) had a best confirmed response of complete response (CR) or stringent CR, 35% (37 vs 34%) had VGPR, 26% (19 vs 32%) had PR, 10% (9 vs 10%) had stable disease (SD), 3% (1 vs 4%) had PD. 7% (8 vs 6%) of pts were not evaluable. In a pooled analysis of both arms, achieving a deeper response was associated with longer PFS (Figure, A) and DOR (median not reached [NR], 42.8, and 15.0 mos for pts with ≥CR, VGPR, and PR, respectively). In 570 pts with ≥PR (288 IRd; 282 pbo-Rd), 152 (53%) and 136 (47%) in the IRd arm and 143 (51%) and 139 (49%) pts in the pbo-Rd arm were defined as early (0-4 mos) and late (>4 mos) responders, respectively. For early vs late responders, 46% vs 40% were aged ≥75 years, 21% vs 12% had International Staging System stage III MM, and 44% vs 33% had expanded high-risk cytogenetic abnormalities. Median PFS was prolonged among late vs early responders with IRd (65.7 vs 21.2 mos) and pbo-Rd (62.6 vs 18.2 mos), as was median DOR (IRd, NR vs 22.6 mos; pbo-Rd, 64.1 vs 17.2 mos). The PFS sensitivity analysis among pts with PFS of ≥6 mos confirmed the association of late response with improved outcomes; among late vs early responders achieving ≥PR, median PFS was 65.7 vs 23.9 mos with IRd and 62.6 vs 18.4 mos with pbo-Rd (Figure, B), and among late vs early responders achieving ≥VGPR, median PFS was 65.7 vs 35.3 mos with IRd and 64.4 vs 21.7 with pbo-Rd. Conclusions: Achieving a deeper response was associated with prolonged PFS and DOR in NDMM patients in TOURMALINE-MM2. PFS benefit on the ITT analysis was driven by the higher rates of deep responses (≥VGPR) with IRd vs pbo-Rd. PFS and DOR were also longer in pts achieving a late vs early best confirmed response of ≥PR or ≥VGPR. Consistent with results from a similar analysis in relapsed/refractory MM in the TOURMALINE-MM1 trial (Garderet Leukemia 2018), our findings support the continuation of therapy with the aim of achieving a deeper response over time. Additional sensitivity analyses will be presented. Figure 1 Figure 1. Disclosures Richardson: Sanofi: Consultancy; AstraZeneca: Consultancy; Celgene/BMS: Consultancy, Research Funding; GlaxoSmithKline: Consultancy; Regeneron: Consultancy; Oncopeptides: Consultancy, Research Funding; Protocol Intelligence: Consultancy; Secura Bio: Consultancy; Janssen: Consultancy; Takeda: Consultancy, Research Funding; AbbVie: Consultancy; Karyopharm: Consultancy, Research Funding; Jazz Pharmaceuticals: Consultancy, Research Funding. Venner: Takeda: Honoraria; BMS: Honoraria; Janssen: Honoraria; Pfizer: Honoraria; Sanofi: Honoraria; GSK: Honoraria. Bahlis: GlaxoSmithKline: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Karyopharm: Consultancy, Honoraria; BMS/Celgene: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria; Genentech: Consultancy; Sanofi: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria. White: Amgen: Consultancy, Honoraria; Antengene: Consultancy, Honoraria; BMS: Consultancy, Honoraria; Forus: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; GSK: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Karyopharm: Consultancy, Honoraria. Karlin: Celgene-BMS: Honoraria, Other: member of advisory board; Sanofi: Honoraria; oncopeptide: Honoraria; Janssen: Honoraria, Other: member of advisory board, travel support; Abbvie: Honoraria; GSK: Honoraria, Other: member of advisory board; Amgen: Honoraria, Other: travel support and advisory board ; Takeda: Honoraria, Other: member of advisory board. Rigaudeau: Takeda: Membership on an entity's Board of Directors or advisory committees. Suzuki: Bristol-Myers Squibb: Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria; ONO: Honoraria; Novartis: Honoraria; Sanofi: Honoraria; Abie: Honoraria; Janssen: Consultancy, Honoraria. Shibayama: Mundi Pharma: Honoraria; Otsuka: Honoraria; Pfizer: Honoraria; Bristol-Myers Squibb: Honoraria; Sanofi: Honoraria; Nippon Shinyaku: Honoraria; Fujimoto: Honoraria; Daiichi Sankyo: Honoraria; AstraZeneca: Honoraria, Membership on an entity's Board of Directors or advisory committees; Essentia Pharma Japan: Research Funding; Chugai: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Eisai: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Avvie: Honoraria, Research Funding; Takeda: Honoraria, Research Funding; Ono: Honoraria, Research Funding; Celgene: Research Funding. Zhang: Takeda: Current Employment. Kumar: Takeda: Current Employment, Current holder of stock options in a privately-held company. Twumasi-Ankrah: Takeda: Current Employment. Labotka: Takeda: Current Employment. Rifkin: Takeda: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees; Fresenius-Kabi: Membership on an entity's Board of Directors or advisory committees; Coherus: Membership on an entity's Board of Directors or advisory committees; McKesson: Current Employment, Current equity holder in publicly-traded company; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb (Celgene): Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees. Lonial: AMGEN: Consultancy, Honoraria; TG Therapeutics: Membership on an entity's Board of Directors or advisory committees; BMS/Celgene: Consultancy, Honoraria, Research Funding; GlaxoSmithKline: Consultancy, Honoraria, Research Funding; Abbvie: Consultancy, Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding; Merck: Honoraria. Kumar: Antengene: Consultancy, Honoraria; Carsgen: Research Funding; Astra-Zeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Oncopeptides: Consultancy; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bluebird Bio: Consultancy; Beigene: Consultancy; Tenebio: Research Funding; Roche-Genentech: Consultancy, Research Funding; Novartis: Research Funding; KITE: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Merck: Research Funding; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Research Funding; BMS: Consultancy, Research Funding; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Adaptive: Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Research Funding. Moreau: Amgen: Honoraria; Oncopeptides: Honoraria; Janssen: Honoraria; Celgene BMS: Honoraria; Sanofi: Honoraria; Abbvie: Honoraria. OffLabel Disclosure: Use of the oral proteasome inhibitor ixazomib in newly diagnosed multiple myeloma patients who are ineligible for transplant.