ALBERT

Description: Background. Survival of patients with high-risk diffuse large B-cell lymphoma (DLBCL) is suboptimal, and the risk of central nervous system (CNS) progression is relatively high. We investigated the efficacy of dose-dense chemoimmunotherapy and systemic CNS prophylaxis in two Nordic trials including patients less than 65 years with high-risk DLBCL. We combined individual patient data from these trials to compare clinical outcome and biological prognostic factors in patients treated with CNS prophylaxis given in the beginning (CHIC) versus at the end (CRY-04) of therapy. Patients and methods. In CRY-04 study, patients were treated with six courses of R-CHOEP14 followed by HD-Mtx and HD-Ara-C. In CHIC trial, treatment started with two courses of HD-Mtx in combination with R-CHOP14, followed by four courses of R-CHOEP-14 and one course of R-HD-AraC. In addition, liposomal AraC was administered intrathecally at courses 1, 3 and 5. For the correlative studies, formalin fixed paraffin embedded pretreatment tumor samples were analyzed by fluorescent in situ hybridization for BCL2 and c-MYC breakpoints and by immunochemistry for CD10, BCL6, MUM1, MYC and BCL2 expression. Germinal center B-cell-like (GCB)/non-GCB) subclassification was performed according to Hans algorithm. Results. Among 303 patients enrolled in the trials (CRY-04, n=160 and CHIC, n=143), 295 (CRY-04, n=154 and CHIC, n=139) were evaluable for baseline characteristics and outcome. Median age (54 and 56 years, p=0.222), male/female ratio, stage, and aaIPI scores were comparable in the two cohorts. CHIC regimen improved outcome over CRY-04; the findings included 4-year estimates of PFS (81% vs 66%, p=0.003), OS (83% and 79%, p=ns) and cumulative incidence rates of CNS progression (2.4% and 5.0%, p=ns). Treatment with the CHIC regimen reduced the risk of systemic progression (aaIPI adjusted RR=0.489, 95%CI 0.308-0.777, p=0.002). PFS benefit with CHIC over CRY-04 was observed across pre-specified subgroups, and particularly in patients less than 60 years old (p=0.008). In the entire study population, dual protein expression (DPE) of BCL2 and MYC was the only parameter to be significantly correlated with a worse PFS (4-y PFS 77% vs 50%, p=0.024; RR=2.300, 95% CI 1.088-4.860, p=0.029). Neither any single immunohistochemical marker nor the GCB/non-GCB subtype or MYC/BCL2-translocations significantly affected outcome. However, when treatment interaction was tested, MYC/BCL2 double hit status (DHL; 13%) predicted poor outcome among patients treated with CRY-04 regimen compared with patients who received CHIC regimen (4-y PFS; 38% vs 78%, p=0.086). GCB subtype and BCL2 positivity were also associated with better outcome in the CHIC cohort (4 y PFS; 63% vs 84%, p=0.011 and 61% vs 80%, p=0.007, respectively), whereas there were no significant survival differences between these regimens among the patients with non-GCB subtype, BCL2 negative DLBCL or DPE lymphomas. Conclusions. Our results derived from trial data with homogenous treatment support the use of HD-Mtx in the beginning rather than at the end of therapy. The survival benefit related to CHIC regimen over CRY-04 is due to better systemic control of the disease, and at least partly linked to improved survival among patients with GCB subtype, BCL2 positivity and DHL. Disclosures Leppa: Takeda: Consultancy, Research Funding; Janssen: Consultancy, Research Funding; Bayer: Research Funding; Roche: Consultancy, Honoraria, Research Funding; Celgene: Consultancy. Holte:Novartis Pharmaceuticals Corporation: Membership on an entity's Board of Directors or advisory committees; Roche, Norway: Research Funding.

Description: Introduction: Survival of patients with high-risk diffuse large B-cell lymphoma (DLBCL) is suboptimal, and the risk of early central nervous system (CNS) progression is high. Here we present the final results from a Nordic phase II study, where dose-dense chemoimmunotherapy including early systemic CNS prophylaxis with high dose methotrexate (HD-Mtx), further intensified by intrathecally (IT) administered liposomal cytosine arabinoside (AraC), was given. Patients and methods: Inclusion criteria were age 18-65 years, de novo DLBCL or grade 3B follicular lymphoma without clinical, radiological or cytological signs of CNS involvement, age adjusted IPI 2-3, WHO performance score 0-3, and/or anatomical sites related to increased risk for CNS recurrence (e.g. testis, facial sinuses, orbita). Treatment consisted of two courses of HD-Mtx in combination with R-CHOP14, followed by four courses of R-CHOEP14 and one course of R-HD-AraC. Liposomal AraC was administered IT at courses 1, 3 and 5 (omitted during a period of production halt). Primary end points were failure free survival (FFS; disease progression, discontinuation of protocolled therapy due to toxicity, death from any cause) and CNS progression rate at 18 months. Among the secondary endpoints were the identification of biological risk factors for high risk disease and prognostic role of cerebrospinal fluid (CSF) cytology-/flow cytometry (FC)+for CNS recurrence. Results: Of the accrued 143 patients, 140 met the inclusion criteria and were evaluable for baseline characteristics and primary endpoints. Of these, 132 had a complete set of treatment data. The male/female ratio was 1.7 and the median age 56 years (range 20-64). The majority of the patients had DLBCL (96%), advanced clinical stage (93%), elevated LDH (91%), more than one extranodal site (73%), and B-symptoms (64%). A bulky lesion (〉10 cm) was present in 37% of the patients and 11 CSF samples (8%) were FC+. Most patients (n=127, 96%) received a full treatment schedule. Liposomal AraC was given to 81 (61%) and radiotherapy to 39 (30%) patients. Grade 4 infections were observed in 12% of the patients. The frequency of grade 3-4 mucositis as well as gastrointestinal toxicity was 20%, and of grade 3 arachnoiditis 2,5%. Three toxic deaths were observed. In addition, three patients developed AML/MDS and one PML. At the end of treatment, CR/CRu, PR and PD rates were 79%, 17% and 3%, respectively. Of the 120 patients who underwent PET-CT, 92 (77%) achieved a metabolic CR (Deauville score (DS) 1-3). Three patients had primary refractory disease. At a median follow-up of 30 months, additional 14 patients had relapsed, three of them in the CNS (only one had a pre-therapeutic FC+ CSF), and 15 had died. FFS, PFS, OS and CNS progression rates at 30 months were 80%, 83%, 90%, and 2.4%, respectively. PET positivity (DS 4-5) at the end of treatment (p=0.019) and BCL2 expression (p=0.049) were associated with increased risk of progression, whereas other factors, such as molecular subtype (GC versus non-GC), Ki-67 score (≥70%), aaIPI group (2 versus 3), number of extranodal sites, FC-based CSF positivity, and treatment with liposomal AraC did not seem to have significant impact on outcome. Conclusions: Safety profile and final outcome results of the Nordic CHIC trial indicate high response rates, favorable survival, low number of CNS recurrences and manageable toxicity as a result of this CNS targeted intensive therapy schedule. PET response at the end of therapy and selected biological factors identify patients at high risk of progression. Disclosures Leppa: Roche: Honoraria, Other: Travel expenses, Research Funding; Janssen: Research Funding; Bayer: Research Funding; Mundipharma: Research Funding; Amgen: Research Funding; Takeda: Honoraria, Other: Travel expenses; CTI Life Sciences: Honoraria; Merck: Other: Travel expenses. Joergensen:Amgen: Research Funding; Mundipharma: Research Funding. Mannisto:SOBI: Honoraria; Pfizer: Honoraria; Gilead: Other: Travel expenses; Celgene: Other: Travel expenses; Novartis: Other: Travel expenses; Amgen: Other: Travel expenses; Takeda: Honoraria, Other: Travel expenses; Roche: Honoraria, Other: Travel expenses. Jerkeman:Gilead: Research Funding; Celgene: Research Funding; Mundipharma: Research Funding; Amgen: Research Funding; Janssen: Research Funding. Holte:Amgen: Research Funding; Mundipharma: Research Funding.

Description: Lymphoplasmacytic lymphoma and marginal zone lymphoma in the bone marrow: paratrabecular involvement as an important distinguishing feature Assia Bassarova, Gunhild Tr¿en, Signe Spetalen, Francesca Micci, Anne Tierens, Delabie Abstract Lymphoplasmacytic lymphoma (LPL) is a neoplasm of small B-lymphocytes, lymphoplasmacytoid and plasma cells involving bone marrow and sometimes lymph nodes and spleen. Lymphoplasmacytic lymphoma is often accompanied by Waldenström macroglobulinemia. Since the original description, Waldenström macroglobulinemia has become recognized as a distinct clinicopathological entity defined by serum IgM paraprotein and bone marrow involvement by lymphoplasmacytic lymphoma. Since serum IgM paraprotein in itself is not specific and can be seen in a variety of small B-cell lymphoproliferative disorders, notable chronic lymphatic leukemia and marginal zone lymphoma, as well as in rare cases of myeloma, the diagnosis of Waldenström macroglobulinemia rests largely upon the proper diagnosis of LPL in the bone marrow. The differential diagnosis between bone marrow involvement by lymphoplasmacytic lymphoma (LPL) and marginal zone lymphoma (MZL) is challenging because histology and immunophenotype of both diseases overlap. The diagnosis may be helped by demonstrating the MYD88 L265P mutation, seen in most LPL. However, the mutation is also present in MZL, although at a lower frequency. To better define the distinguishing features of LPL we studied a series of bone marrow trephine biopsies of 59 patients with Waldenström's macroglobulinemia (WM) without extramedullary involvement and compared the findings with bone marrow biopsies from 23 patients with well-characterized MZL who also had bone marrow involvement. H&E and immunoperoxidase-stained sections of bone marrow trephine biopsies as well as flow cytometry and classical cytogenetics performed on aspirations were reviewed. The study was complemented with MYD88L265P mutation analysis on the bone marrow trephine biopsies of all patients. The features are summarized in Table 1. The most distinguishing features of LPL with respect to MZL were focal paratrabecular involvement (p

Description: Background: CD37 is an internalizing transmembrane antigen highly expressed by normal B cells and on most of B-cell malignancies, and represents an interesting therapeutic target for the treatment of B-cell NHL. 177Lu-DOTA-HH1 (Betalutin®) is a novel CD37-targeting antibody radionuclide conjugate in clinical development. It consists of a CD37-binding murine IgG1 antibody HH1 labelled with the short-ranged beta-emitter lutetium-177 (T½ = 6.7 days) chelated to DOTA. 177Lu-DOTA-HH1 is delivered in a ready-to-use formulation. Efficacy and safety data of patients (pts) receiving 177Lu-DOTA-HH1 with HH1 pre-dosing, as well as new efficacy and safety data from pts receiving 177Lu-DOTA-HH1 without HH1 pre-dosing will be presented. Methods: Pts with relapsed incurable CD37 positive NHL of follicular grade I-IIIA, marginal zone, mantle cell, lymphoplasmacytic and small lymphocytic subtypes and with platelet counts ≥ 150 x109/l were eligible for inclusion in the study. In a 3+3 study design pts received rituximab (375 mg/m2) day 1 and 8 in order to deplete normal B cells. On day 29 pre-dosing with HH1 (50 mg, cold CD37 antibody) was administered before 177Lu-DOTA-HH1 injection (Arm 1). In Arm 2 177Lu-DOTA-HH1 was administered without HH1 pre-dosing on day 29. The starting doses for Arm 1 and 2 were 10 MBq/kg b.w. and 15 MBq/kg b.w, respectively. Pts enrolment has been completed (n=13) in Arm 1 with the dose-limiting toxicity (DLT) observed at 20 MBq/kg bw and a dose expansion cohort is currently open for enrollment at 15 MBq/kg with HH1 pre-dosing. Arm 2 is currently open for enrollment. Tumour response was assessed by FDG PET/CT scans (Cheson 2007), and pts will be followed for 5 years. Results: Arm 1:A total of13 (M/F 11/2) pts, median age 68 years, follicular lymphoma (n=12), and mantle cell lymphoma (n=1) have been enrolled since the study start in December 2012. The range of prior therapies was 1 to 8, where 5 of 13 pts were refractory to rituximab. The most common toxicities observed were hematologic and all DLTs were reversible and manageable. At 20 MBq/kg (n=3) G 3/4 neutropenia and/or thrombocytopenia were observed in all pts and platelet transfusions were required in 2 pts. At 15 MBq/kg (n=6) DLTs were: 1 G 3 thrombocytopenia lasting 〉14 days and 1 G 4 neutropenia/ thrombocytopenia lasting 〉7 days. The median time to nadir for platelets and neutrophils was 40 and 49 days, respectively. No pts experienced febrile neutropenia. Serious AEs were reported in 5 pts: at 10 MBq/kg pneumonia (possibly related) and pulmonary embolism (PE) unrelated, in the same pt, with history of PE; thrombocytopenia requiring platelet transfusions (2 pts) and epistaxis in 1 of them (20 MBq/kg), possibly related; transient atrial fibrillation (2 pts) at 15 MBq/kg, possibly related. No secondary malignancies or other long term events have been observed. Best overall tumor response observed across all dose levels were 4 complete and 3 partial remissions, 2 stable disease and 4 progression of disease (one pt had confirmed transformed lymphoma at 3 months). The duration of response (complete and partial remissions) ranged from 6 to more than 21 months. One patient is still in remission after 2 years. The median response duration has not yet been reached. Arm 2: Inclusion in this arm is ongoing. Data on efficacy and safety will be presented and compared with the pts receiving pre-dosing. Conclusions: 177Lu-DOTA-HH1, which is a single dose ready-to-use formulation, has a predictable and manageable safety profile. Most AEs were hematological in nature, all transient and reversible. Promising efficacy and durable responses have been observed. 177Lu-DOTA-HH1 has the potential to be a novel therapy for B-cell malignancies. Disclosures Kolstad: Nordic Nanovector ASA: Membership on an entity's Board of Directors or advisory committees, Research Funding. Bolstad:Nordic Nanovector ASA: Employment. Bruland:Nordic Nanovector ASA: Equity Ownership. Dahle:Nordic Nanovector ASA: Employment, Equity Ownership. Hartvig Larsen:Nordic Nanovector ASA: Equity Ownership, Membership on an entity's Board of Directors or advisory committees.

Description: 177Lu-Satetraxetan-lilotomab (Betalutin®) is a novel CD37-binding IgG1 antibody labelled with the beta-emitter lutetium-177, in a ready-to-use formulation currently in Phase 1/2 clinical development for the treatment of Non-Hodgkins lymphoma. CD37 is an internalizing transmembrane antigen highly expressed on most B-cell malignancies, and is a promising therapeutic target. The optimisation of the pre-dosing regimen prior to administration of 177Lu-Satetraxetan-lilotomab may result in an improved safety and efficacy profile. The phase 1 stage of this study is designed with 4 arms to test different pre-dosing regimens (no pre-dosing, rituximab and two doses of lilotomab) on the effect of 177Lu-Satetraxetan-lilotomab. Methods: Patients with relapsed incurable NHL of follicular grade I-IIIA, marginal zone, mantle cell, lymphoplasmacytic and small lymphocytic subtypes and with platelet counts ≥ 150 x109/l were eligible for inclusion in the study. All patients received pre-treatment with rituximab (375 mg/m2) to deplete peripheral B cells and improve biodistribution of the labelled antibody. Pre-dosing with lilotomab (cold anti-CD37 antibody) was given in arms 1 and 4 or rituximab in arm 3, within 4 hours of 177Lu-Satetraxetan-lilotomab to block binding in the non-tumour tissue. The pre-treatment and pre-dosing regimen used in each arm is summarised below: Arm 1: rituximab day1 and 8, lilotomab (40 mg) plus Betalutin day 29 Arm 2: rituximab day 1 and 8, Betalutin day 29 Arm 3: rituximab day 1, rituximab plus Betalutin day 15 Arm 4: rituximab day 1, lilotomab (100 mg/m2) plus Betalutin day 15 The starting dose for Arm 1 was10 MBq/kg and was 15 MBq/kg for arm 2, 3 and 4 and in phase 2. Response was assessed by FDG PET/CT scans at 3 and 6 months post-treatment and then by CT scan up to 5 years after treatment. The results of the protocol specified interim analysis will be presented. Results: A total of36 patients have been enrolled into study, of which 24 are currently evaluable. Patients enrolled into the study had either follicular (n=20), mantel cell (n=2) or marginal zone (n=2) lymphoma. The number of prior therapies ranged from 1 to 8. The efficacy and safety results from patients enrolled into Arms 3 and 4 and treated with two different pre-dosing regimens will be presented for the first time. The most common toxicities observed were hematologic with all dose limiting toxicities (DLTs) being reversible and manageable and related to thrombocytopenia and neutropenia. At a dose of 15 MBq/kg, pre-dosing with 40 mg of lilotomab (Arm 1 and phase 2) reduced the incidence of hematological DLTs to 14% (2/14 patients) compared with 100% (2/2 patients) with no pre-dosing in Arm 2. No DLTs have been reported at 10 MBq/kg in either Arm 1 or 2. Fourteen serious adverse events (SAEs) were reported by 8 patients: Atrial fibrillation (n=2) and platelet count decreased (n=2) were the only SAEs reported by more than one patient. There have been no deaths and no secondary malignancies or other long-term safety events. The overall tumor response rate observed in 23 patients evaluable for efficacy was 57%, comprising 7/23 complete responses, 6/23 partial responses, 5/23 stable disease and 5/23 with progressive disease. In addition, one patient had a confirmed transformed lymphoma at 3 months. One patient is still in remission more than 3 years after treatment and two further patients are still in remission more than 2 years after treatment. Conclusions: Betalutin has the potential to be a novel, safe and effective therapy for B-cell malignancies with durable responses. Betalutin, a single dose, ready-to-use formulation, has a predictable and manageable safety profile which is improved by pre-dosing. Most AEs were haematological, all transient and reversible. Disclosures Kolstad: Nordic Nanovector: Other: Membership of Scientific Advisory Board. Illidge:Nordic Nanovector: Consultancy. Dahle:Nordic Nanovector ASA: Employment, Equity Ownership. Baylor Curtis:Nordic Nanovector: Employment. Østengen:Nordic Nanovector: Employment. Turner:Nordic Nanovector: Employment. Hartvig Larsen:Nordic nanovector: Equity Ownership. Holte:Mundipharma: Research Funding; Amgen: Research Funding.

Description: Introduction: Most indolent NHL patients (pts) have advanced stage disease at diagnosis, and no curative therapy exists. The mainstay of both first- and second-line (2L) therapy is anti-CD20 chemo-immunotherapy, and although initially effective, most pts relapse, with median PFS decreasing markedly after 2L and 3rd-line therapies. In addition, many pts eventually develop resistance to rituximab (RTX)/RTX-containing regimens, thus therapeutic targets other than CD20 are important. Those who develop resistance to RTX, especially the elderly, need new treatment approaches. With a median age at diagnosis of 67 (seer.gov), NHL is a disease of the elderly, who are at risk of developing cumulative myelosuppression, cardiac toxicity, and severe infections with currently available therapies. CD37 is highly expressed (〉90%) in B-cell NHL, providing an alternative target to CD20. Lutetium (177Lu) lilotomab satetraxetan (Betalutin®) is a beta-emitting anti-CD37 ARC in a ready-to-use formulation. LYMRIT 37-01 is a phase I/II open-label, multicenter, dose-escalation study to determine the safety, pharmacokinetics (PK), and preliminary efficacy of a single dose of Betalutin in pts with relapsed iNHL, and to establish a recommended phase II dose (RP2D). We present updated efficacy and safety data for the phase I/IIa part of the study (Part A) as of 22 June 2018; all pts have ≥ 6 months (m) of follow-up, except for 3 (will be completed in August). Methods: Pts with histologically confirmed iNHL relapsing after ≥1 prior therapy with 150 x 109/L, no prior SCT/RIT, and a life expectancy of ≥3 months were enrolled into 1 of 4 dose-escalation arms (Part A) to determine the optimal lilotomab pre-dose and Betalutin dose for further evaluation in an expanded phase II cohort. A fifth arm collected additional PK data. All pts received pre-treatment with RTX. Responses were assessed using Cheson IWG response criteria (including CT and FDG PET/CT scans) beginning at week 12. Results: 74 pts [57 follicular (FL), 7 mantle cell (MCL), 9 marginal zone (MZL), 1 small lymphocytic (SLL)] were enrolled at 13 sites from Dec 2012 to Feb 2018. Median age was 68 (range 38-87; 55% ≥ 65); the median no. of prior therapies was 3 (range 1-9); 48 pts (65%) had received ≥2 prior therapies. Two RP2Ds emerged: a lilotomab pre-dose of 40 mg + 15 MBq/kg Betalutin ("40/15"; Arm 1) and a lilotomab pre-dose of 100 mg/m2 + 20 MBq/kg Betalutin ("100/20"; Arm 4). For all pts, the overall response rate (ORR) was 61%, with 26% complete responses (CR). By subtype, the ORR was 65% (CR 24%) for FL, and 78% (CR 44%) for MZL. FL with ≥2 prior therapies (n=37) had an ORR of 70% (CR 27%). With a median follow-up of 9.1 m (range 4.9-49.5 m), the median duration of response for all pts is 13.3 m (20.5 m for those with a CR); 26 pts (35%) have remained free of disease progression for 〉12 m [CR(15)/PR(5)/SD(6)]. For the 36 pts receiving the "40/15" regimen, the ORR was 58% (CR 28%), and 64% (CR 28%) for FL (n=25). The ORR was 63% (CR 21%) for 19 pts receiving the "100/20" regimen, and 69% (CR 19%) for FL (n=16). Betalutinwas well-tolerated. The most common grade (G) 3/4 AEs were neutropenia (53%) and thrombocytopenia (48%); 5 pts (7%) had G3/4 infections (pneumonia, UTI, pharyngitis (G3), 2 G4 sepsis). No febrile neutropenia was reported. Four pts had plt transfusions [low plt count (2), epistaxis (1), hematuria (1)]; 3 received G-CSF. Two pts had infusion reactions; both were related to RTX. SAEs occurred in 14 pts (19%); SAEs in ≥2 pts were atrial fibrillation, thrombocytopenia, lymphoma progression and sepsis (all n=2). Five pts developed transient anti-drug antibodies. One case of CMML occurred 24 m after Betalutin (18 m after subsequent bendamustine-RTX therapy). There were no study drug-related deaths in the treatment period. G3/4 neutropenia and thrombocytopenia occurred in 56%/56% (40/15 regimen) and 47%/42% (100/20 regimen). Conclusions: Betalutin is well tolerated and has promising antitumor activity in recurrent iNHL, especially in FL and MZL. Use of a higher lilotomab pre-dose resulted in a lower incidence of G3/4 hematologic AEs. With a single administration, Betalutin has the potential to be a novel, safe, and effective therapy for pts with B-cell malignancies. The 2 RP2Ds from Part A of the study are now being compared in a randomized phase 2b cohort (Part B: "PARADIGME") in relapsed, RTX/anti-CD20 refractory FL pts who have received ≥2 prior therapies. Disclosures Kolstad: Nordic Nanovector: Membership on an entity's Board of Directors or advisory committees, Research Funding; Merck: Research Funding; Roche: Research Funding. Illidge:Nordic Nanovector: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Seattle Genetics: Consultancy, Research Funding; Takeda: Consultancy, Honoraria. Hajek:Amgen: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Bristol-Myers Squibb: Consultancy, Honoraria, Research Funding. Jurczak:European Medicines Agency: Consultancy, Membership on an entity's Board of Directors or advisory committees; Astra Zeneca: Consultancy; Acerta: Consultancy, Research Funding; Sandoz-Novartis: Consultancy; Afimed: Research Funding; Bayer: Research Funding; BeiGene: Research Funding; Celgene: Research Funding; Epizyme: Research Funding; Gilead: Consultancy, Research Funding; Janssen: Consultancy, Research Funding; Nordic Nanovector: Research Funding; Merck: Research Funding; Morphosys: Research Funding; Pharmacyclics: Research Funding; Servier: Research Funding; Roche: Research Funding; TG Therapeutics: Research Funding. Rojkjaer:Nordic Nanovector: Employment. Østengen:Nordic Nanovector: Employment.