Belada, David

PURPOSE The combination of the Bruton tyrosine kinase inhibitor ibrutinib with bendamustine-rituximab for first-line treatment of mantle cell lymphoma (MCL) prolonged progression-free survival (PFS), but without improvement in overall survival (OS), likely because of toxicity. Acalabrutinib was shown to be efficacious and less toxic than ibrutinib in a head-to-head trial in chronic lymphocytic leukemia and therefore might lead to better outcomes in MCL. METHODS Patients 65 years and older with previously untreated MCL received acalabrutinib (100 mg twice daily) or placebo (until disease progression or unacceptable toxicity), plus six cycles of bendamustine (90 mg/m 2 once daily; days 1 and 2) and rituximab (375 mg/m 2 as a single dose; day 1) followed by rituximab maintenance in responding patients for 2 years. Crossover to acalabrutinib at disease progression was permitted. The primary end point was PFS per the independent review committee; overall response rate and OS were secondary end points. RESULTS In total, 598 patients were randomly assigned, with 299 in each arm. At a median follow-up of 49.8 months using the reverse Kaplan-Meier method, the median PFS was 66.4 months in the acalabrutinib arm and 49.6 months in the placebo arm (hazard ratio [HR], 0.73 [95% CI, 0.57 to 0.94]; P = .0160). Benefit was seen across all subgroups, including those with high-risk features. Overall response/complete response rates were 91.0%/66.6% and 88.0%/53.5% in the acalabrutinib and placebo arms, respectively. OS was not significantly different (HR, 0.86 [95% CI, 0.65 to 1.13]; P = .27). Grade 3 or greater adverse events were reported in 88.9% and 88.2% in the acalabrutinib and placebo arms, respectively. CONCLUSION The combination of acalabrutinib with bendamustine-rituximab significantly improved PFS. Clinical benefit of acalabrutinib with bendamustine-rituximab was achieved with manageable toxicity.

Introduction: The primary analysis of the phase 3 ECHO trial (NCT02972840) demonstrated that acalabrutinib plus bendamustine-rituximab (ABR) significantly improved progression-free survival (PFS) vs placebo plus bendamustine-rituximab (PBR) in older patients (pts) with previously untreated mantle cell lymphoma (MCL) (Wang et al. EHA 2024, Abstract #LB3439). Here we present additional efficacy and safety results from the ECHO trial. Methods: Pts aged ≥65 years (y) with previously untreated MCL and ECOG PS ≤2 were randomly assigned 1:1 to receive ABR or PBR. Acalabrutinib (100 mg twice daily) or placebo was administered until progressive disease (PD) or unacceptable toxicity. Induction with BR was administered for 6 cycles followed by rituximab maintenance (A±R maintenance, cycles 7-30) in pts achieving a partial or complete response (PR or CR). Pts progressing on PBR could cross over to receive acalabrutinib monotherapy. PFS (primary endpoint) was assessed by independent review committee. Minimal residual disease (MRD) negativity rate (10-5) was assessed in peripheral blood (every 24 weeks [wks], at CR, and at PD) and bone marrow (at CR) by NGS-based ClonoSEQ assay (Adaptive Biotechnologies). Results: Among the 598 pts randomized to ABR or PBR (299 in each arm), high-risk baseline characteristics included high-risk simplified MIPI score in 24.1% and 24.4%, blastoid histology in 8.7% and 6.7%, pleomorphic histology in 5.0% and 6.0%, centrally tested Ki-67 ≥30% in 46.5% and 49.2%, and known TP53 mutation in 7.4% and 9.7%, respectively. PFS hazard ratios (HRs) for subgroups were 0.78 (95% confidence interval [CI] 0.51-1.19) in pts with high-risk simplified MIPI score, 0.68 (95% CI 0.29-1.58) in pts with blastoid histology, 0.64 (95% CI 0.25-1.66) in pts with pleomorphic histology, 0.69 (95% CI 0.49-0.98) in pts with Ki-67 ≥30%, and 0.88 (95% CI 0.42-1.78) in pts with known TP53 mutation. In the ABR arm, median PFS was 22.2 months (mo) among pts who discontinued acalabrutinib during induction for reasons other than PD or death, 29.4 mo in pts who discontinued acalabrutinib during A±R maintenance (cycles 7-30) for reasons other than PD or death, and not reached in pts who received acalabrutinib for 31 cycles or more. Among evaluable patients who were MRD negative at the end of induction (24 wks), the rate of conversion to MRD positive during maintenance was lower in the ABR arm (5.85%; n=11/188) than in the PBR arm (15%; n=26/171). Conversely, among evaluable pts who were MRD positive at the end of induction (24 wks), 37.5% (n=3/8) in the ABR arm and 20% (n=3/15) in the PBR arm converted to MRD negative during maintenance. Overall rates of AEs were similar in each arm during induction, but were higher in ABR during A±R maintenance (cycles 7-30) and more so in the monotherapy phase (cycle 31+). Grade ≥3 TEAEs (ABR vs PBR) were 70.0% vs 68.7% during induction, 64.9% vs 62.9% during A±R maintenance (cycles 7-30), and 57.0% vs 45.3% during monotherapy (cycle 31+). Similarly, rates of TEAEs leading to discontinuation of acalabrutinib/placebo were 8.1% vs 8.8% during induction, 23.9% vs 19.0% during A±R maintenance (cycles 7-30), and 25.9% vs 13.7% during monotherapy (cycle 31+). Exposure-adjusted incidence rates per 100 person-years reduced the difference between ABR and PBR for clinically relevant TEAE rates (32.6 vs 29.3 for grade ≥3 serious TEAEs; 4.2 vs 4.0 for grade 5 TEAEs; 15.5 vs 12.4 for TEAEs leading to acalabrutinib/placebo discontinuation), possibly due to longer median exposure to acalabrutinib (28.6 vs 24.6 mo). Conclusion: Acalabrutinib in combination with BR provides a significant PFS benefit in pts with previously untreated MCL, including those with high-risk features. Furthermore, the addition of acalabrutinib to BR provided a greater PFS effect among pts in the ABR arm with the longest exposure to acalabrutinib. The PFS improvement may be partially driven by the contribution of acalabrutinib to sustained MRD-negative status and deepened responses after the end of induction. ABR provides this clinical benefit without excess toxicity as shown by attenuated differences between arms in exposure-adjusted incidence rates, suggesting that higher AE rates in the ABR arm are likely due in part to the longer duration of acalabrutinib treatment vs placebo. These data emphasize the benefits of acalabrutinib in frontline MCL treatment in high-risk pts and the additional benefit of continuous therapy.

Abstract Anti-CD19 immunotherapy tafasitamab is used in combination with lenalidomide in patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL) who are ineligible for autologous stem cell transplant. Open-label, phase 1b, First-MIND study assessed safety and preliminary efficacy of tafasitamab + R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) ± lenalidomide as first-line therapy in patients with DLBCL. From December 2019 to August 2020, 83 adults with untreated DLBCL (International Prognostic Index 2-5) were screened and 66 were randomly assigned (33 per arm) to R-CHOP-tafasitamab (arm T) or R-CHOP-tafasitamab-lenalidomide (arm T/L) for 6 cycles. Primary end point was safety; secondary end points included end-of-treatment (EoT) overall response rate (ORR) and complete response (CR) rate. All patients had ≥1 treatment-emergent adverse event, mostly grade 1 or 2. Grade ≥3 neutropenia and thrombocytopenia occurred, respectively, in 57.6% and 12.1% (arm T) and 84.8% and 36.4% (arm T/L) of patients. Nonhematologic toxicities occurred at similar rates among arms. R-CHOP mean relative dose intensity was ≥89% in both arms. EoT ORR was 75.8% (CR 72.7%) in arm T and 81.8% (CR 66.7%) in arm T/L; best ORR across visits was 90.0% and 93.9%. Eighteen-month duration of response and of CR rates were 72.7% and 74.5% (arm T) and 78.7% and 86.5% (arm T/L); 24-month progression-free and overall survival rates were 72.7% and 90.3% (arm T) and 76.8% and 93.8% (arm T/L). Manageable safety and promising signals of efficacy were observed in both arms. Potential benefit of adding tafasitamab + lenalidomide to R-CHOP is being investigated in phase 3 frontMIND (NCT04824092). This study is registered at www.clinicaltrials.gov as #NCT04134936.

e19553 Background: The combination of tafa + LEN has accelerated approval in the United States (2020) and conditional approval in Canada and Europe (2021) for R/R DLBCL in ASCT-ineligible adult pts. A tolerable safety profile for R-CHOP + tafa ± LEN in pts with newly diagnosed DLBCL in the Phase Ib First-MIND study (NCT04134936) was previously reported, with numerically superior efficacy for R-CHOP + tafa + LEN (ASH 2021; #3556). We report PK, PD, and immunogenicity of R-CHOP + tafa ± LEN in this first line setting. Methods: Eligible pts ≥18 years with treatment-naïve DLBCL, IPI 2–5, and ECOG PS 0–2 were randomized 1:1 to either six 21-day (D) cycles (C) of R-CHOP (R-CHO, D1; P, D1–5) + tafa (12 mg/kg IV, D1, 8, 15) (Arm A) or R-CHOP + tafa + LEN (25 mg orally, D1–10) (Arm B). Secondary endpoints included tafa serum conc and number and percentage of pts developing anti-tafa Abs. Exploratory endpoints included natural killer (NK) cell, T-cell, and B-cell count in peripheral blood. Results: Data cut-off: 13 March 2021 for safety analysis, incl. ≥1 month follow-up after EoT visit for all pts; 15 September 2021 for efficacy. Tafa serum conc reached steady state by C3 (geometric mean trough conc: Arm A, 186.40–216.55 µg/mL; Arm B, 171.77–201.54 µg/mL) and steadily declined after treatment completion. Anti-tafa Abs were detected in 1/65 (1.5%) pts. This pt showed pre-existing tafa Abs at baseline, which decreased during treatment. Median NK cell count decreased from baseline at C1D8 but was at baseline or higher levels by EoT visit (Arm A) and C1D15 (Arm B; Table). T-cell count decreased from baseline at C1D8 in both arms but was at baseline level or higher by C1D15 (Arm A) and EoT visit (Arm B). Median B-cell count decreased from baseline to 0 cells/μL (Arm A, C1D15; Arm B, C1D8); at 6-month follow-up after EoT visit, B-cell count had recovered to measurable levels in ̃50% of pts. Conclusions: Tafa serum conc reached and maintained a therapeutic dose level in this first-line regimen and declined in line with known tafa half-life (̃16 days) after treatment completion; tafa levels were comparable between the two treatment arms. No pt developed treatment-induced or treatment-boosted anti-tafa Abs. Median NK-cell, T-cell, and B-cell counts were comparable between treatment arms in all cycles. Clinical trial information: NCT04134936. [Table: see text]

Abstract Introduction Tafasitamab is a humanized, Fc-modified, anti-CD19 monoclonal antibody (mAb) shown to enhance antibody-dependent cellular cytotoxicity and phagocytosis. It is approved by the FDA under accelerated approval (July 2020) in combination with lenalidomide (LEN) for treatment of relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL) in adult patients ineligible for autologous stem cell transplantation. To evaluate if newly diagnosed DLBCL patients would also benefit from this regimen, this Phase Ib study (First-MIND; NCT04134936) was designed to first assess the safety and tolerability of tafasitamab ± LEN in addition to rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) in newly diagnosed DLBCL patients. Methods Eligible patients were ≥18 years old, with treatment-naïve DLBCL, international prognostic index (IPI) 2-5 and Eastern Cooperative Oncology Group performance status (ECOG PS) 0-2. Patients with known double- or triple-hit and transformed lymphoma were excluded. Patients were randomized 1:1 to either six 21-day [D] cycles of R-CHOP (R-CHO, D1; P, D1-5) + tafasitamab (12 mg/kg IV, D1, 8, 15) (Arm A) or R-CHOP + tafasitamab + LEN (25 mg orally, D1-10) (Arm B). Granulocyte colony-stimulating factor and venous thromboembolism prophylaxis was mandatory. The primary safety endpoint was incidence of treatment-emergent adverse events (TEAEs); secondary endpoints included overall response rate (ORR), positron emission tomography (PET)-complete response (CR) rate, and partial response (PR) rate at end of treatment (EOT). Tumor measurements by PET/CT or PET/MRI at EOT were performed according to Lugano 2014 criteria within 6±2 weeks after Day 21 of the last treatment cycle the patient started. Results From December 2019 to August 2020, 83 patients were screened in nine countries across 34 sites in Europe and the US; 66 were randomized (Arm A, n=33; Arm B, n=33). Data cut-off for this analysis: 13 March 2021. Median age was 64.5 years (range 20-86). Many patients had high-risk disease: IPI 2: 24/66 (36.4%), IPI 3: 29/66 (43.9%), IPI 4: 11/66 (16.7%), IPI 5: 2/66 (3.0%); ECOG PS ≥2: 6/66 (9.1%). Most patients had Stage III/IV disease 62/66 (93.9%); 29/66 (43.9%) had bulky disease. All patients experienced at least one TEAE. The most frequent Grade ≥3 TEAEs by system organ class were blood and lymphatic disorders (81.8% patients overall), experienced by 24 patients (72.7%) in Arm A and 30 patients (90.9%) in Arm B. Grade ≥3 neutropenia and thrombocytopenia occurred in 19/33 (57.6%) and 4/33 (12.1%) (Arm A), and 28/33 (84.8%) and 12/33 (36.4%) (Arm B) patients, respectively; Grade ≥3 febrile neutropenia was experienced by 6/33 (18.2%) patients in each arm. Grade ≥3 infusion-related reactions to both rituximab and tafasitamab occurred in no patients in Arm A and one patient (3.0%) in Arm B, and 7/33 (21.2%) (Arm A) and 9/33 (27.3%) (Arm B) patients had a Grade ≥3 infection and/or infestation (Figure 1). Serious TEAEs occurred in 14/33 (42.4%) patients in Arm A and 17/33 (51.5%) patients in Arm B. Two out of 33 (6.1%) and one out of 33 (3.0%) patients discontinued study treatment due to TEAEs in Arms A and B, respectively. There were four deaths unrelated to tafasitamab and/or LEN (COVID-19 pneumonia, sepsis, and urosepsis). The average relative dose intensity of R-CHOP in each cycle was maintained in both arms. ORR at EOT was observed in 25/33 patients (75.8%; 95% confidence interval [CI]: 57.7-88.9) in Arm A and 27/33 patients (81.8%; 95% CI: 64.5-93.0) in Arm B. Conclusion These data suggest that both regimens are tolerable and do not impair dosing and scheduling of R-CHOP. Toxicities were similar to those expected with R-CHOP with or without LEN. With tumor follow-up still ongoing, the ORR at EOT suggests that patients with treatment-naïve DLBCL may achieve clinically meaningful efficacy tafasitamab and LEN in addition to standard treatment. A Phase III, multicenter, randomized, double-blind, placebo-controlled trial will assess efficacy and safety of R-CHOP + tafasitamab + LEN vs R-CHOP in newly diagnosed patients with high intermediate and high risk DLBCL, and is currently recruiting (frontMIND study; NCT04824092). Funding: MorphoSys AG. Figure 1 Figure 1. Disclosures Belada: Roche: Consultancy, Other: Travel, Accommodations, Expenses, Research Funding; Gilead Sciences: Consultancy, Other: Travel, Accommodations, Expenses, Research Funding; Janssen-Cilag: Consultancy, Research Funding; Takeda: Consultancy, Other: Travel, Accommodations, Expenses, Research Funding; MorphoSys AG: Consultancy, Research Funding; Debiopharm Group: Consultancy; Pharmacyclics: Research Funding; Archigen Biotech: Research Funding; Reddys: Research Funding. André: Johnson & Johnson: Research Funding; Roche: Other: Travel/accomodation/expenses, Research Funding; Incyte: Consultancy; Gilead: Consultancy, Other: Travel/Accommodations/Expenses; Karyopharm: Consultancy; Bristol-Myers-Squibb: Consultancy, Other: Travel/Accommodations/Expenses; Takeda: Consultancy, Research Funding; Celgene: Other: Travel/accomodation/expenses; AbbVie: Other: Travel/accomodation/expenses. Pérez Persona: Amgen: Consultancy, Other: Support for attending meetings and/or travel, Speakers Bureau; BMS/Celgene: Consultancy, Other: Support for attending meetings and/or travel, Speakers Bureau; AbbVie: Other: Support for attending meetings and/or travel, Speakers Bureau; Takeda: Speakers Bureau; Sanofi: Consultancy, Speakers Bureau; AstraZeneca: Speakers Bureau; GSK: Consultancy; Incyte: Consultancy. Staber: Roche: Consultancy, Honoraria, Research Funding; AbbVie: Consultancy, Honoraria; Gilead: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Astra Zeneca: Consultancy, Honoraria; Takeda: Consultancy, Research Funding; MSD: Consultancy, Honoraria; BMS: Consultancy, Honoraria; Incyte: Consultancy, Honoraria, Research Funding; Beigene: Consultancy, Honoraria. Trneny: AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses; Amgen: Consultancy, Honoraria; Bristol-Myers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses; Gilead Sciences: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses; Incyte: 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, Other: Travel, Accommodations, Expenses; MorphoSys: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses; Celgene: Consultancy; 1st Faculty of Medicine, Charles University, General Hospital in Prague: Current Employment; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Portola: Honoraria, Membership on an entity's Board of Directors or advisory committees; AstraZeneca: Honoraria. Brackertz: MorphoSys AG: Current Employment. Shah: MorphoSys AG: Current Employment. Sporchia: MorphoSys AG: Current Employment. Burke: MorphoSys: Consultancy; Adaptive Biotechnologies: Consultancy; Verastem: Consultancy; AstraZeneca: Consultancy; Bristol Myers Squibb: Consultancy; Kymera: Consultancy; X4 Pharmaceuticals: Consultancy; AbbVie: Consultancy; SeaGen: Consultancy, Speakers Bureau; Kura: Consultancy; Roche/Genentech: Consultancy; Epizyme: Consultancy; Beigene: Consultancy, Speakers Bureau. Nowakowski: Celgene, NanoString Technologies, MorphoSys: Research Funding; Celgene, MorphoSys, Genentech, Selvita, Debiopharm Group, Kite/Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees. OffLabel Disclosure: Tafasitamab is a humanized Fc-modified cytolytic CD19 targeting monoclonal antibody. In combination with lenalidomide (LEN), it received accelerated approval in July 2020 for adult patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) not otherwise specified (NOS), including arising from lowâ€'grade lymphoma, who are ineligible for autologous stem cell transplant (ASCT). Following FDA approval, we are now evaluating the safety and efficacy of tafasitamab in combination with LEN as an add-on to first-line therapy with R-CHOP in newly diagnosed patients with DLBCL.

7540 Background: Tafasitamab is a humanized, Fc-modified anti-CD19 monoclonal antibody that enhances antibody-dependent cellular cytotoxicity and phagocytosis. It is FDA-approved with LEN for adult patients (pts) with relapsed/refractory (R/R) DLBCL ineligible for autologous stem cell transplantation. First-MIND (NCT04134936) is a Phase Ib, open-label, randomized study of tafa + R-CHOP or tafa + LEN + R-CHOP in newly diagnosed DLBCL. Methods: Eligible pts were ≥18 years, treatment-naïve, with histologically confirmed DLBCL not otherwise specified, international prognostic index (IPI) 2–5 and ECOG performance status (PS) 0–2. Pts with known double- or triple-hit and transformed lymphoma were excluded. Treatment (Tx) comprised six 21-day cycles of tafa (12 mg/kg IV, Day [D] 1, 8, 15) + R-CHOP (arm A) or tafa (12 mg/kg IV, D1, 8, 15) + LEN (25 mg orally, D1–10) + R-CHOP (arm B). G-CSF and VTE prophylaxis was mandatory. Primary objective is safety; secondary objectives are ORR, PET-CR rate at end of Tx, PFS, long-term safety, pharmacokinetics, immunogenicity. Results: From Dec 2019 to Aug 2020, 83 pts were screened in Europe and the US; 66 were randomized (33 per arm). Data cut-off for this analysis: 9 Dec 2020; study is ongoing. Median age was 64.5 years (range 20–86). Overall, 30% (20/66) of pts were ≥70 years and many had high-risk disease: IPI 2 29%, IPI 3 46%, IPI 4 26%. ECOG PS: 47% of pts were ECOG PS 0, 44% PS 1, 9% PS 2. Most pts had stage III/IV disease (92%); 46% had bulky disease. All pts experienced a treatment-emergent adverse event (TEAE). Grade ≥3 neutropenia and thrombocytopenia occurred in 54.5% and 12.1% (arm A) and 66.7% and 30.3% (arm B) of pts, respectively (Table). Serious TEAEs occurred in 42.4% (arm A) and 51.5% (arm B) of pts. There were three deaths, unrelated to tafa and/or LEN (sepsis, urosepsis, and COVID-19 pneumonia). R-CHOP dose intensity was maintained in both arms. Among 60 pts who completed tumor assessments after cycle 3, ORR was 89.7% (arm A) and 93.5% (arm B). Conclusions: These data suggest R-CHOP + tafa or tafa + LEN is tolerable in pts with Tx-naïve DLBCL and that R-CHOP dosing is not affected. Toxicities are similar to those expected with R-CHOP or R-CHOP + LEN. Updated safety and early efficacy data will be presented at the conference. Clinical trial information: NCT04134936. [Table: see text]

PURPOSE Patients with the activated B-cell-like (ABC) subtype of diffuse large B-cell lymphoma (DLBCL) historically showed inferior survival with standard rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). Phase II studies demonstrated that adding the immunomodulatory agent lenalidomide to R-CHOP improved outcomes in ABC-type DLBCL. The goal of the global, phase III ROBUST study was to compare lenalidomide plus R-CHOP (R2-CHOP) with placebo/R-CHOP in previously untreated, ABC-type DLBCL. METHODS Histology and cell-of-origin type were prospectively analyzed by central pathology prior to random assignment and study treatment. Patients with ABC-DLBCL received lenalidomide oral 15 mg/d, days 1-14/21 plus standard R-CHOP21 versus placebo/R-CHOP21 for six cycles. The primary end point was progression-free survival (PFS) per independent central radiology review. RESULTS A total of 570 patients with ABC-DLBCL (n = 285 per arm) were stratified by International Prognostic Index score, age, and bulky disease, and randomly assigned to R2-CHOP or placebo/R-CHOP. Baseline demographics were similar between arms. Most patients completed six cycles of treatment: 74% R2-CHOP and 84% placebo/R-CHOP. The most common grade 3/4 adverse events for R2-CHOP versus placebo/R-CHOP were neutropenia (60% v 48%), anemia (22% v 14%), thrombocytopenia (17% v 11%), and leukopenia (14% v 15%). The primary end point of PFS was not met, with a hazard ratio of 0.85 (95% CI, 0.63 to 1.14) and P = .29; median PFS has not been reached for either arm. PFS trends favoring R2-CHOP over placebo/R-CHOP were seen in patients with higher-risk disease. CONCLUSION ROBUST is the first DLBCL phase III study to integrate biomarker-driven identification of eligible ABC patients. Although the ROBUST trial did not meet the primary end point of PFS in all patients, the safety profile of R2-CHOP was consistent with individual treatments with no new safety signals.