Moyo, Tamara K.

Abstract Secondary central nervous system (CNS) large B-cell lymphoma (SCNSL) occurs in the de novo setting, as a CNS-isolated relapse, or synchronous (concomitant CNS and systemic) relapse. SCNSL is a devastating event without therapeutic consensus. Thus, we aimed to evaluate treatment outcomes in an international cohort. Progression-free survival (PFS), overall survival (OS), and cumulative incidence of relapse (CIR, estimated using competing-risk models) were reported. Prognostic factors were identified in a 6-month landmark multivariate analysis. Outcomes after thiotepa autologous stem cell transplant (ASCT) and chimeric antigen receptor (CAR) T-cell therapy (CAR-T) delivered at relapse were compared after propensity score matching (PSM). A total of 1139 patients were included in the analysis (de novo: 537; relapsed SCNSL: 602). Two-year PFS estimates were 40.4%, 43.9%, and 16.2% for de novo SCNSL, CNS-isolated relapse, and synchronous relapse, respectively. Patients with CNS-isolated relapse demonstrated low rates of systemic recurrence (24-month CIR, 6%). Thiotepa-ASCT correlated with longer survival in de novo SCNSL (PFS: hazard ratio [HR], 0.57; P = .005; and OS: HR, 0.62; P = .023) and CNS-isolated relapses (PFS: HR, 0.55; P = .002; and OS: HR, 0.39; P< .0001). ASCT (thiotepa or no thiotepa) also associated with improved survival in synchronous relapses (PFS: HR, 0.57; P = .023; and OS: HR, 0.48; P = .019). Higher survival with thiotepa-ASCT than CAR-T was observed after PSM (PFS: HR, 0.45; P = .005 and OS: HR, 0.41; P = .014). These data support thiotepa-ASCT in eligible patients, particularly de novo disease and CNS-isolated relapses. CNS-isolated relapse was infrequently associated with systemic recurrence, supporting treatment regimens adopted from primary CNS lymphoma.

Abstract The benefit of rituximab maintenance after first-line (1L) bendamustine-rituximab (BR) in patients with mantle cell lymphoma (MCL) remains uncertain, with inconsistent results from the phase 2 MAINTAIN trial and several retrospective studies. We conducted a large retrospective study at 27 US and Canadian academic centers to examine the benefit of rituximab maintenance after BR. A total of 911 patients received 1L BR between 2010 and 2020, and 703 had an objective response and no evidence of disease progression at the 3-month post-BR landmark. Among those, 394 (56%) received rituximab maintenance and 309 (44%) did not, with largely similar baseline patient and disease characteristics. In the landmark analysis, rituximab maintenance was associated with improved event-free survival (EFS; median, 49.9 vs 29.7 months; P< .001) as well as overall survival (OS; median, 109.5 vs 74.2 months; P< .001). The EFS and OS benefits were observed across most of the subgroups. EFS and OS differences were statistically significant in those who achieved a complete response to 1L BR (n = 590; median EFS, 62.7 vs 31.1 months [P< .001]; median OS, 136.1 vs 75.3 months [P< .001]), but the analysis among those who achieved a partial response to 1L BR was limited by the small sample size. These results provide additional evidence for the survival benefit of rituximab maintenance after BR in MCL and support its use in clinical trial design and routine practice.

Introduction: Scant data exist on prognostic factors, survival and treatment (Tx)-related outcomes in SCNSL. We conducted a multicenter international analysis to identify prognostic factors and outcomes in SCNSL at diagnosis (de novo), or after frontline Tx (1L) either with (concomitant) or without (isolated) systemic (syst) relapse. Methods: This study collected data from patients (pts) treated between 2001-2023 at 35 centers. Overall (OS) and progression-free survival (PFS) were calculated from SCNSL diagnosis to first event (death for OS, relapse/death for PFS) or last follow-up. Uni- (UVA) and multivariable (MVA) Cox analyses were performed to assess prognostic factors; Kaplan-Meier method was used to estimate survival. Results: 1173 (US: 863, UK: 273, Canada: 37) pts with SCNSL were included. Baseline characteristics were median age: 62 years (interquartile range 52.5-69), male sex: 58.7%, elevated LDH: 71.1%, stage III/IV: 88.6%, HIV: 3%, transformed LBCL (tLBCL): 13.8%, non-germinal center B-cell like (non-GCB) subtype: 52.3%, double expressor (DE): 40%, MYC rearrangement (MYC-R): 28.3%, MYC/BCL2 double hit: 16.6%, MYC/BCL2/BCL6 triple hit (TH): 6.1%. Among 522 pts with de novo SCNSL, 84.2% had involvement of a single CNS compartment (44.7% brain parenchyma; 40.4% leptomeningeal [lepto]). 1L regimens included 36.2% R-CHOP with high-dose methotrexate (HD-MTX), 12.5% MARIETTA-type, and 9.8% R-CODOX-M/IVAC; 54.6% received intrathecal chemotherapy. Consolidation Thiotepa-based autologous stem cell transplant (TT-ASCT) occurred in 15.3%. The majority of pts who underwent TT-ASCT had previously achieved CR or PR in syst (92.5%) and CNS (72.5%) compartments. At median follow-up 25.7 months (mos), subsequent relapse was observed in 27.5% TT-ASCT recipients: 36.3% had isolated CNS, 27.4% syst, and 36.3% concomitant. 588 pts presented with SCNS after 1L (66.2% isolated, 33.8% concomitant). Brain parenchyma involvement was observed in 56.8%, lepto in 22.6%. Tx included 31.6% HD-MTX combination (eg, R-MPV, MTR); 18.4% HD-MTX +/- rituximab; 16.2% MARIETTA-type; and 9.4% platinum-based regimen. Consolidation TT-ASCT occurred in 22.4% (n=132), and 13.8% (n=81) received CAR-T cell therapy (excluding subsequent relapses in de novo group). Syst (65.1%) & CNS (69.1%) responses (CR/PR) were higher before TT-ASCT compared to CAR-T cell (49.5% & 54.5%, respectively). After TT-ASCT, 52 pts (39.3%) relapsed, mainly in the CNS (n=30, 57.7%), with only 4 (7.7%) concomitant. After CAR-T, 48 pts (59.3%) relapsed: 15 (31.2%) isolated in CNS and 15 (31.2%) concomitant. 12-month cumulative incidence of relapse (with death as competing risk) was 21.1% after TT-ASCT and 55.8% after CAR-T. In 63 pts (5.4%), the first CNS event occurred >2 lines of Tx. With median follow-up of the entire cohort of 24.6 mos, median PFS and OS were 11 and 21 mos, respectively. mPFS and mOS were significantly better in pts with de novo SCNSL (13.4 & 47.4 mos) compared to SCNSL after 1L (10.4 & 14.2 mos) and >2 lines of Tx (6.5 & 9.7 mos); P<0.0001. Factors associated with significantly shorter OS in UVA across all presentations were age >60, male sex, GCB subtype, MYC-R, tLBCL, DE, TH, elevated LDH, ECOG PS ≥2, SCNSL after 1L (vs. de novo), and failure to achieve syst/CNS response to 1L. Of these, age >60, male sex, MYC-R, ECOG PS ≥2, and failure to achieve response to 1L remained significant in MVA. In de novo cases, age >60, DE, ECOG PS≥2, and failure to achieve syst/CNS response to 1L were associated with poorer OS; for pts with SCNSL after 1L, age >60, GCB subtype, and ECOG PS ≥2 were significant. Pts treated with HD-MTX-based regimens after 1L experienced longer OS than those treated with platinum regimens or high-dose cytarabine. In de novo cases, TT-ASCT was significantly associated with longer OS (HR=0.58; P=0.025) in MVA after adjusting for significant factors, 1L type, and response. For SCNSL at relapse, TT-ASCT (HR=0.34; P<.0001) and isolated SCNSL presentation (vs. concomitant HR=0.70, P=0.007) were associated with longer OS, adjusting for significant factors, type of second-line Tx, & site of CNS relapse. Conclusions: This study represents the largest analysis of SCNSL inclusive of all modes of presentation. Concomitant SCNSL at relapse was associated with poor outcomes, while TT-ASCT consolidation was associated with improved OS in de novo & relapsed disease. Despite advances in LBCL SCNSL remains an unmet therapeutic need.

Background: Myelodysplastic/Myeloproliferative neoplasms (MDS/MPN) represent a group of rare hematologic malignancies, distinguished by their concurrent dysplastic and proliferative features. Patients with these neoplasms have an increased risk of acute leukemia transformation and often present with extramedullary and constitutional symptoms. The only approved therapies for MDS/MPNs are hydroxyurea, decitabine (oral decitabine/cedazuridine and parenteral decitabine) or azacitidine (parenteral) for pts with CMML. Given the rarity and the heterogeneity of MDS/MPNs, prospective studies focusing specifically on MDS/MPN have been uncommon, and refining treatment strategies has been difficult. ABNL-MARRO ( A Basket study of Nove l therapy for untreated MDS/MPN and Relapsed/ Refractory Overlap Syndromes) is an international cooperative effort that leverages the expertise of the MDS/MPN International Working Group (IWG) and provides a framework for collaborative studies around the world to advance treatment of MDS/MPN and to explore clinical and pathologic markers of disease severity, prognosis, and treatment response (Moyo TK et.al BMC Cancer. 2022). Methods: ABNL-MARRO 001 (AM-001) is an open-label, phase 1b/2 study testing the treatment combination of ASTX727 (days 1-5), a fixed dose oral combination pill containing 35 mg of the DNMTi decitabine (DEC) and 100 mg of the cytidine deaminase inhibitor cedazuridine (CED), together with a series of active agents in myeloid disease (see Figure 1a) for MDS/MPN. In arm A, ASTX727 is combined with itacitinib 300 mg (days 1-28), a selective JAK1 inhibitor in newly diagnosed and relapsed/refractory (R/R) pts. Here we report results from the 3+3 dose de-escalation phase 1b portion used to determine the recommended Phase 2 dose (RP2D) in arm A. Dose-limiting toxicities (DLTs) were assessed in cycle 1. Disease response was assessed by the MDS/MPN IWG response criteria (Savona et.al., Blood. 2015). Results: Seven patients were enrolled with a median age 75 (range 32-82) years with newly diagnosed (4 pts) or R/R (3 pts) MDS/MPN. Three patients had CMML, 2 had MDS/MPN-U, and 2 had refractory MDS/MPN RST. One patient was not DLT evaluable given severe disease-induced cytopenia, and was not included in the assessment (patient 4 in Figure 1b). The majority of pts experienced a treatment-emergent adverse event (TEAE) of any grade; the most common (≥30% of pts) were thrombocytopenia (50%), neutropenia (30%), and constipation (30%); 50% of pts experienced a Grade ≥3 TEAE; the most common was neutropenia (30%). No DLTs were reported, and these AEs were consistent with what has been reported in the use of ASTX727 (Savona et al. Blood. 2022). One patient achieved a CR, and two additional patients had the best overall response of optimal marrow response after receiving 6 cycles of treatment. All patients are alive with a median follow-up of 12 months (range 6-17 months). The clinical responses and time-on-treatment of all pts in phase 1b are summarized in Figure 1b. Summary/Conclusion: Based on the preliminary results of the phase 1b study, the dosing schedule of 35 mg DEC / 100 mg CED daily for 5 days in combination with itacitinib 300 mg daily for 28 days was selected as the RP2D as it balanced clinical efficacy with an acceptable and manageable safety profile. This regimen and dose are being utilized in a 28-day cycle in the ongoing global, multi-center phase 2 study (NCT04061421).

Background: Bendamustine and rituximab (BR) is a standard-of-care first-line (1L) therapy for older or unfit patients with mantle cell lymphoma (MCL). The SHINE trial compared BR with rituximab maintenance plus ibrutinib vs placebo in patients ≥65 years old and showed that the ibrutinib arm had significantly improved progression-free survival (PFS; median 80.6 vs 52.9 months) but similar overall survival (OS; 57% vs 55% at 7 years) compared to the placebo arm. Whether sequential treatment with BR in 1L and a Bruton's tyrosine kinase inhibitor (BTKi) in second-line (2L) can result in a similar cumulative PFS compared to 1L BR plus BTKi combination therapy is unknown. To provide insight to this question, we modeled observational data to evaluate MCL outcomes after 1L BR and 2L BTKi therapy in the BTKi era. Methods: Patients with MCL who received 1L BR with or without rituximab maintenance in 2014-2020 at one of the 27 participating centers were included. Exclusion criteria included participation in the SHINE or ECHO trials, any additional 1L therapy other than BR (with or without rituximab maintenance), and stem cell transplant consolidation after 1L BR. Baseline characteristics, treatment, and follow-up data were abstracted by chart review. Event-free survival (EFS) was defined as time from index line treatment start to the first event (progression, relapse, retreatment, or death). OS was defined as time from index line treatment start to death. Using an intention-to-treat (ITT) framework, EFS2 was defined as time from 1L BR start to progression, relapse, or retreatment following 2L BTKi treatment or death. Patients who received a non-BTKi treatment at 2L were censored for EFS2 at 2L treatment start; living patients without an event following 1L BR or 2L BTKi were censored for EFS2 at last follow-up. Results: A total of 618 patients with MCL who received 1L BR in 2014-2020 were included. The median age was 71 (IQR 65-76) years, and 447 (72%) were male. 59 (11%) patients had an ECOG PS ≥2, 566 (93%) had stage III-IV disease, and simplified MIPI was low in 105 (21%), intermediate in 200 (39%), and high in 202 (40%) patients. The median follow-up following 1L BR start was 57.4 (95% CI 53.8-63.2) months. Response data were available in 580 patients, and the best ORR was 92% (79% complete response [CR] and 13% partial response [PR]). 258 (42%) patients received rituximab maintenance. As of last follow-up, 255 patients were alive and in remission after 1L BR, 92 patients died without 2L therapy, and 271 patients received a 2L therapy. The median EFS was 34.1 (95% CI 31.0-40.0) months. The median OS was 97.8 (95% CI 81.2-NA) months, the 5-year OS rate was 58.6% (95% CI 54.4-63.2), and the 7-year OS rate was 56.7% (95% CI 52.4-61.5) (Fig 1). Among the 271 patients who started a 2L treatment, 203 (75%) received a BTKi at 2L - 101 (50%) ibrutinib, 76 (37%) acalabrutinib, and 26 (13%) zanubrutinib. The median follow-up following 2L BTKi start was 38.5 (95% CI 31.3-45.1) months. Response data were available in 171 patients, and the best ORR was 64% (36% CR, 28% PR). The median EFS was 10.7 (95% CI 7.7-14.0) months, and the median OS was 24.8 (95% CI 17.3-33.1) months with 2L BTKi therapy (Fig 2). By ITT analysis, the median EFS2 following 1L BR and 2L BTKi was 72.1 (95% CI 56.7-97.8) months (Fig 1). A subset analysis of patients aged ≥65 years (n=471; 198 [42%] received rituximab maintenance) showed similar results. The median EFS with 1L BR was 32.7 (95% CI 29.1-36.3) months. The median OS was 81.5 (95% CI 65.0-NA) months, and the 7-year OS rate was 53.3% (95% CI 48.3-58.7). 208 patients received a 2L therapy, 163 (79%) with a BTKi. The median EFS was 11.5 (95% CI 7.6-15.8) months, and the median OS was 21.0 (95% CI 14.0-29.6) months with 2L BTKi therapy. By ITT analysis, the median EFS2 following 1L BR and 2L BTKi was 58.0 (95% CI 50.2-77.0) months. Conclusion: In this multicenter retrospective study, initiation of 1L BR (with or without rituximab maintenance) resulted in a 7-year OS of 57%. Median EFS2 for sequential 1L BR and 2L BTKi was 72.1 months. In context, the SHINE study reported a median PFS of 80.6 months in the BR (with rituximab maintenance) plus ibrutinib arm and a 7-year OS of 57% in the ibrutinib arm and 55% in the placebo arm, where 39% of patients received a BTKi in 2L. Within the constraints of observational data, our results provide support for sequential use of BR in 1L and BTKi in 2L for patients with MCL.

Abstract Purpose: Treatment options are limited beyond JAK inhibitors for patients with primary myelofibrosis (MF) or secondary MF. Preclinical studies have revealed that PI3Kδ inhibition cooperates with ruxolitinib, a JAK1/2 inhibitor, to reduce proliferation and induce apoptosis of JAK2V617F-mutant cell lines. Patients and Methods: In a phase I dose-escalation and -expansion study, we evaluated the safety and efficacy of a selective PI3Kδ inhibitor, umbralisib, in combination with ruxolitinib in patients with MF who had a suboptimal response or lost response to ruxolitinib. Enrolled subjects were required to be on a stable dose of ruxolitinib for ≥8 weeks and continue that MTD at study enrollment. The recommended dose of umbralisib in combination with ruxolitinib was determined using a modified 3+3 dose-escalation design. Safety, pharmacokinetics, and efficacy outcomes were evaluated, and spleen size was measured with a novel automated digital atlas. Results: Thirty-seven patients with MF (median age, 67 years) with prior exposure to ruxolitinib were enrolled. A total of 2 patients treated with 800 mg umbralisib experienced reversible grade 3 asymptomatic pancreatic enzyme elevation, but no dose-limiting toxicities were seen at lower umbralisib doses. Two patients (5%) achieved a durable complete response, and 12 patients (32%) met the International Working Group-Myeloproliferative Neoplasms Research and Treatment response criteria of clinical improvement. With a median follow-up of 50.3 months for censored patients, overall survival was greater than 70% after 3 years of follow-up. Conclusions: Adding umbralisib to ruxolitinib in patients was well tolerated and may resensitize patients with MF to ruxolitinib without unacceptable rates of adverse events seen with earlier generation PI3Kδ inhibitors. Randomized trials testing umbralisib in the treatment of MF should be pursued.

Abstract Background: Therapies for myelofibrosis (MF) are limited and most are palliative. The JAK1/2 inhibitor ruxolitinib reduces spleen size and MF-related symptoms and improves survival, but can be limited by dose-dependent anemia and thrombocytopenia. Moreover, nearly half of ruxolitinib responders relapse within 5 years. PI3Kd is highly expressed in MF patient samples, independent of ruxolitinib pre-exposure. In JAK2-mutated cell lines, inhibition of PI3K/AKT signaling reduced proliferation and clonogenic potential. The once daily, next generation PI3Kd inhibitor TGR-1202 inhibited PI3K/AKT signaling and led to apoptosis in leukemia and lymphoma cell lines and was well-tolerated in clinical studies, with a toxicity profile distinct from that of ruxolitinib and other PI3Kd inhibitors. We hypothesized that adding TGR-1202 to ruxolitinib could resensitize or augment the response of MF patients with lost or suboptimal response to single-agent ruxolitinib. Objective: To assess safety of TGR-1202 in combination with ruxolitinib in MF patients Secondary Objectives: Hematologic response, symptom assessment Methods: MF patients who had sub-optimal responses to ruxolitinib continued their highest tolerated dose of ruxolitinib without change for ≥ 8 weeks, and were assigned to escalating doses of TGR-1202 in a standard 3+3 algorithm. Adverse events (AEs) were graded by NCI-CTCAE v4.03. Efficacy was assessed according to IWG-MRT consensus response criteria. Symptoms were assessed by the MPN symptom assessment form total symptom score (TSS). All patients received Pneumocystis pneumonia prophylaxis after cycle 1. Results: Eleven MF patients were enrolled and received 400 mg (n=3), 800 mg (n=6), or 600 mg TGR-1202 (n=2) daily. Nine were evaluable for response. Median age was 66y, 73% were male. All had ECOG PS 0-1. Five patients had mutations in JAK2, 4 in CALR, and 3 in MPL; these were mutually exclusive with exception of 1 patient with CALR and MPL mutations (Table 1). Median number of cycles of TGR-1202 + ruxolitinib treatment was 5 (1-13). Grade 2 anemia was the most common AE (Table 2). Two patients had asymptomatic Grade 3 elevations in amylase and lipase that persisted after drug was held, meeting criteria for dose limiting toxicities (DLTs) in 2 separate cohorts (TGR-1202 800mg+ruxolitinib 15mg BID and TGR-1202 800mg+ruxolitinib 10mg BID). Both patients had peak plasma TGR-1202 concentrations 1.5-2x higher than the other patients receiving 800mg TGR-1202, although steady-state levels were equivalent. The maximum tolerated dose (MTD) of TGR-1202 in combination with ruxolitinib was not established. Two patients went off-study due to AEs, and 3 due to progressive disease. One of 9 evaluable patients achieved complete remission and 7 had stable disease. Seven of the 9 evaluable patients had improvement in hematologic parameters and 8 had reduced MF symptoms with a median 33% decrease in TSS (Fig. 1). Conclusions: TGR-1202 + ruxolitinib was well-tolerated. Pharmacokinetic data were consistent with single-agent TGR-1202 (unpublished data), indicating that ruxolitinib does not alter absorption or metabolism of TGR-1202. Grade 3 elevations in amylase and lipase were considered DLTs, per protocol. Although the clinical significance of these asymptomatic laboratory findings is not clear, the protocol was amended to further assay these labs and to exclude concomitant medications with the potential to increase amylase/lipase. Importantly, no grade ≥3 hepatotoxicity, colitis, or thrombocytopenia was seen and no MTD was found. Although only one patient achieved CR, 89% demonstrated clinical benefit with the addition of TGR-1202 to ruxolitinib, supporting further exploration of this combination. Disclosures Strickland: Alexion Pharmaceuticals: Consultancy; Ambit: Consultancy; Baxalta: Consultancy; Boehringer Ingelheim: Consultancy, Research Funding; CTI Biopharma: Consultancy; Daiichi Sankyo: Consultancy; Sunesis Pharmaceuticals: Consultancy, Research Funding; Abbvie: Research Funding; Astellas Pharma: Research Funding; Celator: Research Funding; Cyclacel: Research Funding; GlaxoSmithKline: Research Funding; Karyopharm Therapeutica: Research Funding; Sanofi: Research Funding. Miskin:TG Therapeutics, Inc: Employment, Equity Ownership. Cavers:TG Therapeutics: Employment, Equity Ownership. Sportelli:TG Therapeutics, Inc.: Employment, Equity Ownership. Michaelis:Pfizer: Equity Ownership; Cellgene Corporation: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Incyte Corporation: Consultancy, Honoraria. Mesa:CTI: Research Funding; Promedior: Research Funding; Celgene: Research Funding; Gilead: Research Funding; Incyte: Research Funding; Galena: Consultancy; Ariad: Consultancy; Novartis: Consultancy. Savona:Amgen Inc.: Membership on an entity's Board of Directors or advisory committees; TG Therapeutics: Research Funding; Ariad: Membership on an entity's Board of Directors or advisory committees; Takeda: Research Funding; Sunesis: Research Funding; Incyte: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees.