ALBERT

Description: Introduction: Secondary CNS dissemination (SCNSL) is a rare but lethal event in pts with diffuse large B-cell lymphoma (DLBCL). It can occur both at presentation, in pts with systemic disease, or at relapse, during or after primary therapy. Following the experience from primary CNS lymphoma, pts with SCNSL are currently treated with high-dose-methotrexate-based chemo and autologous transplant (ASCT). However, this strategy is associated with poor control of extra-CNS disease, and only 1/3 of pts proceed to ASCT and recover from this event. Thus, we designed a multicenter phase II trial addressing an intensified chemoimmunotherapy consolidated by ASCT in HIV-neg pts with SCNSL (NCT02329080). Methods: Inclusion criteria were: histologically confirmed DLBCL; CNS involvement at presentation (concomitant to systemic disease) or relapse (isolated or concomitant to systemic lymphoma); age 18-70 ys; ECOG-PS ≤3; no prior treatment with high-dose methotrexate. Registered pts received 3 courses of MATRIX followed by 3 courses of RICE combined with intrathecal chemo and consolidated by BCNU-thiotepa/ASCT. The primary endpoint was 1-yr PFS. The Fleming design was used; to detect a difference in 1-yr PFS from 50% (P0) to 65% (P1), 69 pts were required (one-sided, type I error 5%, power 80%), with a dropout of 10%, 76 pts were needed. If ≥41 pts were progression-free at 1 yr, the strategy would be considered effective. Results: Between 3/2015 and 8/2018, 79 pts were enrolled at 24 centers in 4 countries; 75 pts (median age 58, range 23-70; 38 males) were assessable. CNS involvement was recorded at presentation in 32 (43%) pts and at relapse in 43 (isolated site in 15, concomitant to systemic relapse in 28). CNS sites were brain parenchyma in 34 (45%) pts, brain + eyes in 10 (13%), brain + CSF in 13 (17%), brain + CSF + eyes in 6 (8%), CSF/meninges in 8 (11%), spinal cord in 2 (3%), and eyes in 2 (3%). Median time to CNS involvement was 5 months (range 1-61) in the 43 pts registered at relapse; 20 (47%) of them had refractory disease. 320 (71%) of the 450 planned chemo courses were delivered; 64 (85%) pts received intrathecal chemo. 78 SAEs were recorded in 42 pts, mostly due to FN and infections (64) or bleeding (5); 74 (95%) SAEs were followed by recovery. The 4 lethal SAEs (TRM= 5%) and the 5 transient interruptions occurred during MATRIX. Dose reductions were indicated in 33 (10%) courses. Most common g4 toxicities were thrombocytopenia in 118 (37%) courses, neutropenia in 113 (35%) and infections in 9 (3%). Stem cells collection was successful (median of 6.75M/kg; range: 2.4 - 45) in 42 (88%) of the 48 pts referred for leukapheresis. 55 (73%; 95%CI 63-83%) pts achieved a response after 2 courses of MATRIX; 19 (95%) of the 20 pts who had a CR after 2 MATRIX maintained the response after RICE; 9 (26%) of the 35 pts who had a PR after 2 MATRIX achieved a CR after RICE. Conversely, only 3 of 16 pts with PD/SD after 2 MATRIX achieved a response from RICE. 49 pts (65%; 95%CI 54-76%) achieved a response after MATRIX-RICE induction, and 36 responders received ASCT; 13 responders did not receive ASCT due to insufficient mobilization (n=4), PD due to treatment delay (5), frailty (2), neurological decline (1), and consent withdrawal (1). 45 pts (60%; 95%CI 50-70%) had responsive disease after the whole treatment. At 1 year from registration, 41 pts were progression free (efficacy threshold ≥41). At a median follow-up of 25 (12-47) months, 31 pts are progression free, with a 2-yr PFS of 42 ± 6% for the whole series and 75 ± 7% for the 36 transplanted pts (Fig. A & B). Sites of relapse/progression were CNS in 10 pts, extra-CNS organs in 9 and both in 18. Overall, 33 pts are alive, with a 2-yr OS of 42 ± 6% for the whole series and 82 ± 7% for transplanted pts. Causes of death were lymphoma (35) and toxicity (4); 3 pts died without evidence of disease due to neurological decline, PTE and sudden death. Pts with CNS disease at presentation had the best outcome (Fig. C), whereas CSF/meningeal disease (Fig. D) and age 〉60 ys were independently associated with poor outcome. Conclusions: MATRIX-RICE followed by ASCT achieved the primary endpoint in this very-poor-prognosis population, without major safety concerns. Survival figures of transplanted pts seem a little better than reported in prior trials, whereas pts with MATRIX-refractory disease had no benefit from crossing to RICE. The best survival figures were recorded in chemo-naïve pts treated at presentation and in pts without CSF/meningeal disease. Figure Disclosures Ferreri: Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Roche: Research Funding. Doorduijn:Roche: Honoraria, Research Funding. Nassi:Merck: Consultancy; Takeda: Consultancy; Janssen: Consultancy. McKay:Janssen: Honoraria, Speakers Bureau; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; MSD: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Epizyme: Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Davies:ADCT Therapeutics: Honoraria, Research Funding; Karyopharma: Membership on an entity's Board of Directors or advisory committees, Research Funding; MorphoSys AG: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bayer: Research Funding; Janssen: Honoraria, Research Funding; Kite Pharma: Membership on an entity's Board of Directors or advisory committees; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; GSK: Research Funding; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Honoraria, Research Funding; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Acerta Pharma: Honoraria, Research Funding; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; BioInvent: Research Funding. Fox:Celgene: Consultancy; Gilead: Consultancy; AbbVie: Consultancy; Janssen: Consultancy; Sunesis: Consultancy; Takeda Pharmaceuticals: Consultancy; Atara Biotherapeutics: Consultancy; Adienne: Other: Travel Support. Osborne:Gilead: Membership on an entity's Board of Directors or advisory committees; NIL: Employment; NIL: Other: leadership; NIL: Other: Stock & other ownership interests; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pfizer: Honoraria, Speakers Bureau; MSD: Membership on an entity's Board of Directors or advisory committees. Liberati:Incyte: Consultancy; Novartis: Other: Clinical trial support; Janssen: Honoraria; AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Clinical trial support; Roche: Other: Clinical trial support; Amgen: Membership on an entity's Board of Directors or advisory committees, Other: Clinical trial support; Celgene: Honoraria, Other: Clinical trial support; Bristol-Myers Squibb: Honoraria; Takeda: Membership on an entity's Board of Directors or advisory committees; Servier: Honoraria, Membership on an entity's Board of Directors or advisory committees. Zambello:Janssen: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Zucca:Celltrion Helathcare: Membership on an entity's Board of Directors or advisory committees; AstraZenaca: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Research Funding; Merck: Research Funding; Roche: Membership on an entity's Board of Directors or advisory committees, Other: Travel Grant, Research Funding; Kite, A Gilead Company: Membership on an entity's Board of Directors or advisory committees; Abbvie: Other: Travel Grant. Cwynarski:Adienne: Consultancy; Takeda: Consultancy, Other: conference and travel support , Speakers Bureau; Roche,: Consultancy, Other: conference and travel support, Speakers Bureau; Autolus: Consultancy; KITE: Consultancy; Gilead: Consultancy, Other: conference and travel support, Speakers Bureau; Celgene: Consultancy; Atara: Consultancy; Janssen: Other: conference and travel support, Speakers Bureau.

Description: Introduction: PTCL is a rare and heterogeneous group of non-Hodgkin lymphoma (NHL) comprising ~10% of cases. CHOP is frequently used first-line, but with the exception of ALK+ anaplastic large-cell lymphoma (ALCL), long term outcomes are historically poor with reported 5-yr overall survival (OS) rates of 36%. We retrospectively evaluated the outcomes following first-line chemotherapy for patients with PTCL treated at the Royal Marsden (RM) and Christie (CH) hospitals over a 10-year period. Methods: All eligible patients with PTCL aged ≥18 years and treated at the RM and CH between 1st January 2002 and 31st January 2012 were included. The study was approved by our institutional review boards. Patients were identified from hospital databases and included if they had received at least 1 cycle of first-line chemotherapy. Precursor T-cell malignancies, mycosis fungoides and adult T-cell leukaemia/lymphoma were excluded, as was cutaneous T-cell lymphoma not requiring combination chemotherapy. Clinical data were collated from electronic patient records and the diagnosis of PTCL was confirmed in all cases by an expert haematopathologist. Response was assessed using the IWG 1999 criteria. OS and progression free survival (PFS) were calculated from date of start of 1st line treatment and analysed using Kaplan Meier methods and Cox regression model. The impact of clinical factors on survival was assessed using Cox regression analysis. Results: A total of 143 (RM n=69, CH n=74)patients were evaluable and the median follow-up was 63.4 months. The median age at diagnosis was 59 yrs (range 18-89 yrs). PTCL subtypes were: PTCL not otherwise specified (NOS) (n=48), angioimmunoblastic T-cell lymphoma (AITL) (n=37), ALCL ALK- (n=24), ALCL ALK+ (n=14) and other (n=20). First-line chemotherapy included CHOP (n=97), GEM-P (gemcitabine, cisplatin and methylprednisolone) (n=16), other gemcitabine containing regimen (n=7), asparaginase (n=2) or other (n=21). OS by PTCL subtype is shown in Figure 1. Response was evaluable for 125/143 patients. Overall response (ORR) to first-line chemotherapy was 81.4% with complete response (CR) seen in 42.4%. For the entire cohort (n=143) 5-yr PFS was 20.6% and 5-yr OS was 39.6%. For CHOP treated patients ORR was 80.5% with CR in 43.7%, 5-yr PFS was 25.5% and 5-yr OS was 41.2%. ORR with GEM-P was 78.6% with CR in 50%, 5-yr PFS was 13.6% and 5-yr OS was 39.1%. No statistically significant difference between CHOP and GEM-P was seen in terms of response, OS or PFS. Autologous stem cell transplantation (autoSCT) was performed post first-line induction in 15% (n=22). For patients in CR post induction (CR1) (n=41), we compared survival for those treated with (n=12) and without (n=29) subsequent autoSCT. AutoSCT in CR1 was associated with a trend towards better PFS (HR 0.36, 95%CI 0.13-1.02; p=0.056) but not OS (HR 0.72, 95% CI 0.21-2.47; p=0.599). Uni- (UVA) and multivariate analyses (MVA) were performed to determine the impact of the following on OS and PFS: age (≤60 vs 〉 60yrs), gender, stage (I-III vs IV), performance status (PS, 0-1 vs 2), B symptoms (present vs absent), ethnicity (white vs other), LDH (normal vs elevated), IPI (low vs intermediate vs high), PTCL subtype, number of extranodal sites (0-1 vs 〉1), chemotherapy (CHOP vs gemcitabine based vs other), CR post induction (present vs absent) and autoSCT (performed vs not). Factors with a p-value of

Description: Introduction Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma (NHL) and has an aggressive natural history. R-CHOP has improved patient (pt) survival and established a standard of first line care. In the rituximab era the prognosis for relapsed DLBCL is poor, with salvage chemotherapy and autologous stem cell transplantation (ASCT) only curing a small proportion (1.5cm)) were treated with up to six cycles of 96-hour continuous intravenous (iv) infusions of AZD1152 as an inpt every 3 weeks. Due to concerns over possible precipitation of drug in the line, regular 4 hourly saline flushes were required via each lumen to maintain patency. Prophylactic G-CSF was permissible per ASCO guidelines. Ongoing cycles were commenced when neutrophils recovered to ≥1.0x109/L and platelets to ≥50x109/L. The primary endpoint was overall response rate (ORR). Secondary end-points were progression-free survival (PFS) at one year, % change in tumour size, and safety measured by the incidence and severity of adverse events (AEs). Response assessment using FDG-PET was completed at day 15 of cycle 2. Pts with stable disease (SD), minimal, partial (PR) or complete response (CR) according to Cheson criteria remained on protocol, but those with progressive disease (PD) were taken off study. As data that suggests MYC overexpression may enhance responses to aurora B kinase inhibition, MYC by IHC and FISH for c-MYC translocation was performed. All diagnostic specimens were reviewed by specialist haemato-pathologists. Results Fifteen pts were enrolled in 20 months, and received 1-6 cycles. Overall, 42 cycles were administered (41 at full dose). One pt completed all six planned cycles. The cohort included 8 males and 7 females, with a median age of 65 (35-74 years). 13% had a low International Prognostic Index (IPI) (0-1), 53% an intermediate IPI (2-3) and 33% a high IPI (4-5). The best ORR was 20% (see Fig 1 for tumour percentage reduction) with no cases of CR and 3 PR. 33% obtained SD for between 2-6 cycles. The median PFS was 60 days (95% CI 36-84 days) (see Fig 2). IPI (p=0.584) (See Fig 3), gender (p=0.113), disease bulk at diagnosis (p= 0.654) or c-MYC dysregulation (p=0.331) did not predict PFS. Early discontinuation occurred in 14 pts from PD. Safety Most AEs were grade 1-2. 18 episodes of neutropenic fever occurred, including one grade 4 bacteraemia. There were no fatal SAEs and each episode resolved with iv antibiotics and G-CSF. All other toxicities were transient, manageable and expected. 13% of pts developed a total of 2 episodes of mucositis following 42 total doses. Neutropenia (grade 3-4), diarrhoea and nausea were common but manageable and expected. No Suspected Unexpected Serious Adverse Reactions occurred. Conclusions Three-weekly AZD1152 was safely administered to pts with relapsed DLBCL. Responses were seen, providing a proof of concept that Aurora B kinase is a valid target in DLBCL. However, efficacy was modest. The infusate delivery was cumbersome. Dose intensity was maintained during treatment. Important but manageable AEs included neutropenic fever and mucositis. Aurora B kinase is a rational target for further investigation. NCT01354392. Fig 1: Best % change in SPD from baseline Fig 1:. Best % change in SPD from baseline Fig 2: PFS with 95% confidence intervals Fig 2:. PFS with 95% confidence intervals Fig 3: PFS by IPI Fig 3:. PFS by IPI Disclosures No relevant conflicts of interest to declare.

Description: Introduction Diffuse large B cell lymphoma (DLBCL) and osteoporotic fracture are commoner in older patients (pts). Steroids and chemotherapy are recognised as a risk factor (RF) for fragility-related fracture and its associated morbidity. A small randomised trial (RCT) (Westin 2013) showed bisphosphonates stabilize bone mineral density (including all ages / histologies) in NHL pts. Despite this, there is a lack of data defining the specific incidence and fracture risk in older DLBCL pts post R-CHOP. We aimed to better define this risk in this specific cohort. Methods Data on consecutive DLBCL pts ≥70 years (y) treated with R-CHOP were retrospectively collected across 7 UK centres (2009-2019). Follow up was censored in 07/2019. All pts had untreated, de novo DLBCL or untreated transformed (to DLBCL) indolent B cell NHL. PTLD, HIV and pre-treated NHL pts were excluded. All pts received 1-9 cycles of full or attenuated R-CHOP with curative intent. Pts were excluded if they had progressive disease (PD) or died 〈 6 months (m) of cycle 1 R-CHOP (RCHOP1). A detailed anonymised database included ECOG performance status (PS), body mass index (BMI), history of osteoporosis / osteopenia, documented steroid pre-phase, vitamin D supplementation, calcium and alkaline phosphatase levels, and sites of bone DLBCL involvement. Fractures at diagnosis (DLBCL-related/unrelated) and pre diagnosis were collected. Fractures (including bone site) occurring during 18m from RCHOP1 were identified from radiology records. Pts were followed for a minimum of 6m and censored at 18m from RCHOP1, or at their last follow up if 〈 18m or at PD or death if between 6-18m. Baseline pt characteristics were descriptive. Survival analyses were performed using Kaplan Meier methods and Cox regression with comparisons between categories using the log-rank test. Time to event analyses were measured from RCHOP1 until fracture event. Primary end point was 18m cumulative fracture incidence censoring pts at death or relapse. Univariable and multivariable analyses (UVA; MVA) of potential influencing RFs for fracture was assessed by Cox regression (Final stepwise model; p=0.1 for inclusion). Results Of 589 pts identified, 92 pts had PD or died prior to 6m and were excluded. 20 pts were excluded due to short follow up. Across 477 pts, the median age was 77 (range 70-93) y. 66% had an ECOG PS 0-1. The median cycles given was 6 (range 1-9). 27.3% received pre-phase steroids. The median BMI was 25.5 (range 14.2-48.1). 8.1% had a fracture prior to DLBCL, and 9.1% had a history of osteopenia or osteoporosis. 5.7% were current smokers, 3% had rheumatoid arthritis, 13.5% had type (T) 2 diabetes (DM), and 4.5% had a history of excess alcohol. At baseline, 25.2% had PET or CT-assessed cortical bone involvement. Overall, there were 52 fractures, including 50 within 18m follow up. Cumulative fracture incidence was 6.3% (95% confidence interval (CI) 4.4 - 8.9) at 6m, 9.5% (95% CI 7.1 - 12.6) at 12m and 11.5% (95% CI 8.8 - 14.9) at 18m (Fig A). 6 pts had multiple fracture sites (2; n=5, 3; n=1). 32 (62%) had vertebral fracture(s). Thoracic (34% 20/59) and lumbar vertebral (27% 16/59) were dominant sites (Fig C). 7/52 fractures were at the site of DLBCL involvement, 17/52 were at a different site from initial bone DLBCL involvement, 27/52 were in pts without bone involvement and 1/52 was unknown. Univariable RFs included female sex (hazard ratio (HR) 1.89 (95% CI 1.05 - 3.28)), known osteopenia or osteoporosis (HR 2.64 (95% CI 1.32 - 5.29)), DLBCL-related fracture at diagnosis (HR 4.05 (95% CI 2.07 - 7.92) (Fig B). Initial bone involvement was only associated with an increased risk in pts with a DLBCL-related baseline fracture (95% CI HR 4.56 (2.27 - 9.17)) (Table 1). MVA showed that DLBCL-related baseline fracture (HR 4.32 (1.97 - 9.47)) was the only significant independent RF for fracture with low BMI (p=0.051) and smoking history (p=0.052) of borderline significance (Table 2). Conclusions This is the largest series to date to show there is a clinically relevant fracture risk in older DLBCL pts specifically receiving R-CHOP in early follow up. Our data have limitations inherent to a retrospective study including the potential for unknown confounders, missing data, and medical record misinterpretation. Prospective data is required to validate RFs identified which could enable targeting a high-risk population. An RCT is needed to determine the value of prophylactic intervention(s) in high risk pts. Figure Disclosures Gibb: Takeda: Research Funding. Collins:Gilead: Consultancy, Honoraria. Eyre:Janssen: Honoraria; Abbvie: Honoraria; Gilead: Consultancy, Honoraria, Other: commercial research support; Roche: Honoraria.

Description: Introduction: First-line (1L) therapy for diffuse large B-cell lymphoma (DLBCL) can cure ~60% of patients (pts), but ~10-15% do not respond and 20-25% relapse. Salvage chemotherapy with autologous stem cell transplant (ASCT) is standard for 'fit' pts with relapsed or refractory (R/R) disease. However ~50% of pts are ineligible for transplant and most who undergo ASCT will relapse; for these pts options are extremely limited. Here we evaluated R/R DLBCL treatment patterns and outcomes for pts managed at a single UK center to create a detailed 'real-world' comparator for novel therapies. Methods: A detailed retrospective analysis of medical records was undertaken for pts with DLBCL 2006-2017 and a R/R event 2011-2017. Additional eligibility criteria were: age ≥18 years; ≥1 prior anti-CD20 antibody-containing chemo-immunotherapy regimen; no history of high-grade transformation; and no lymphomatous CNS involvement. Pt characteristics, treatments, responses, and overall survival (OS) were reported by line (L) of therapy (2L, 3L, 4L+) in all pts and in refractory pts (defined as no response to or relapse within 6 months of last treatment). Results: Of 2025 pts diagnosed with DLBCL 2006-2017, 89 fulfilled eligibility including a R/R event 2011-2017: 89, 63, and 41 received 2L, 3L, and 4L+ treatment. Median age at 2L was 66 years (range 58-72). 58.4% (n=52) were male and 64.0% (n=57) were stage III/IV; 49.4% (n=44) were ABC subtype and 29.2% (n=26) were GCB. Systemic 2L therapies (≥5% incidence) included R-DHAP (20.2%; n=18), R-GDP (20.2%; n=18), DHAP (10.1%; n=9), R-GCVP (7.9%; n=7), and gemcitabine (5.6%; n=5). In 2L, 23.6% (n=21) of pts underwent ASCT. With each line, regimens became more diverse, with increased use of experimental therapies. Overall response rate was 46.1% in 2L, 27.0% in 3L, and 9.8% in 4L+. In refractory pts, it was 34.8%, 21.2%, and 7.9% (Table). OS is shown in the Figure and Table; 2-year OS was 30.6% in all R/R pts and 20.5% in refractory pts. Median OS was reduced in pts with low ECOG performance status or high LDH. Two-year OS was 71.4% in transplanted pts (n=23) and 16.3% in non-transplanted pts. Conclusions: Despite multiple treatment options, pts with R/R DLBCL have a very poor prognosis, highlighting the need for rapid introduction of more effective therapies. This can be facilitated by robust data such as these, which may be used for comparing outcomes of novel therapies with those expected at a given line of treatment in the 'real world', unrestricted by the requirements of a trial protocol. Results will be compared with those from the SCHOLAR-1 study (Crump et al. Blood 2017;130:1800-8) to provide greater clarity regarding R/R DLBCL treatment outcomes in the 'real world' setting. Disclosures Radford: Seattle Genetics: Consultancy, Honoraria; Takeda: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria; ADC Therapeutics: Consultancy, Research Funding; AstraZeneca: Equity Ownership, Research Funding; GSK: Equity Ownership; BMS: Consultancy, Honoraria. Castro:F. Hoffmann-La Roche Ltd: Employment. Chaturvedi:Christie Hospital NHS Trust: Employment. Spielewoy:F. Hoffmann-La Roche Ltd: Employment. Gibb:Takeda: Research Funding. Surinach:Genesis Research: Employment. Shang:F.Hoffmann-La Roche AG: Employment. Wenger:F. Hoffmann-La Roche Ltd: Employment, Equity Ownership. OffLabel Disclosure: "Atezolizumab (atezo) is a programmed death-ligand 1 (PD-L1) blocking antibody. In the United States, atezo is approved for treatment of pts with locally advanced or metastatic urothelial carcinoma who are: not eligible for cisplatin-containing chemotherapy (chemo) and whose tumors express PDL-1, or are not eligible for any platinum-containing chemo regardless of PD L1 status; or have disease progression during or following any platinum-containing chemo, or within 12 months of neoadjuvant or adjuvant chemo. Atezo is also approved: in combination with bevacizumab, paclitaxel and carboplatin for first-line treatment of pts with metastatic non-squamous non-small-cell lung carcinoma (NSCLC) with no EGFR or ALK genomic tumor aberrations, and for pts with metastatic NSCLC who have disease progression during or following platinum-containing chemo; in combination with paclitaxel protein-bound for the treatment of adults with unresectable locally advanced or metastatic triple-negative breast cancer whose tumors express PD-L1; and in combination with carboplatin and etoposide, for the first-line treatment of adults with extensive-stage small cell lung cancer. Atezo is not approved for treatment of pts with multiple myeloma."

Description: BACKGROUND Outcomes for patients (pts) with primary CNS diffuse large B cell lymphoma (PCNSL) have improved over recent years, largely through optimisation of first-line methotrexate (MTX)-containing protocols and dose-intensive chemotherapy consolidation. However, 30-50% of pts experience refractory or relapsed (r/r) disease, which confers very poor outcomes and short survival. By contrast to systemic DLCBL, there is no accepted standard approach for r/r PCNSL. Thiotepa is an alkylating agent highly efficient at crossing the BBB and widely incorporated within high-dose therapy and autologous stem cell transplantation (HDT-ASCT) protocols for PCNSL, but has not undergone dose-finding studies nor been incorporated within salvage regimens for PCNSL. The TIER study investigates the safety and efficacy of adding thiotepa, in a dose-escalation design, to the Rituximab, Ifosphamide and Etoposide (R-IE) salvage regimen1. METHODS TIER is an open label, phase I/II UK NCRI TAP study for pts with r/r PCNSL, previously treated with a high-dose MTX-based regimen. In phase I, the RP2D of thiotepa within the TIER combination was established using a 3+3 design, with dose escalations of 30, 40 and 50mg/m2 (dose level 2 (n=4), 3 (n=5) and 4 (n=27) respectively), given on day 5 of R-IE cycle1. The Phase II primary endpoint was overall response rate (ORR) after cycle 2 of TIER (C2) by centrally reviewed contrast-enhanced MRI2, on an intention-to-treat (ITT) basis. Further treatment and consolidation after the primary endpoint MRI was at the discretion of investigators. Key secondary end-points were 2-year PFS, EFS and OS. RESULTS Thirty-six pts were recruited from Jun 2015-Apr 2019 at 13 centres (characteristics: Table 1). The median number of prior lines was 2 (range 1-4) with 44% of patients deemed refractory to their previous line of therapy. During phase I (n=10) no dose limiting toxicities (DLTs) were observed up to and including 50mg/m2 thiotepa, constituting the RP2D (n=27). 56 cycles of TIER were administered across both phases; 5 pts had 〉1 dose reductions. Median time between C1D1 and C2D1 was 24.7 days (range 22-38). Relative mean dose intensity of thiotepa, ifosphamide and etoposide was 71.8 (SD 44.9), 76.4 (SD 41.6), and 76.8 (SD 41.8) respectively. Further therapy after 2 cycles of TIER was delivered to 41.7% of pts (16.7% ASCT, 22.2% TIE, and 2.8% WBRT). The most common grade 3 / 4 adverse events were thrombocytopenia and neutropenia (47.2 and 55.6% occurring in 15 and 18 pts respectively). 17 serious adverse events (SAEs) were reported in 12 pts, of which 4 were haematological. Of these, 13 were considered related to TIER. Commonly occurring non-haematological SAEs were respiratory tract infections (23.5%) and seizures (11.8%). At data lock, 10/27 pts had responded to treatment as assessed by local investigators (ORR 37%, CR rate 15%). 13 pts were non-evaluable (7 progressed prior to C2 scan, 2 withdrew consent, and 4 awaiting scans) and classed as non-responders. Following data lock, responses were reported for 3 further pts (2 by local investigators and 1 by central review), resulting in a provisional ORR of 13/27 (48%). For the ITT population, median OS time was 3.52 months (95% CI 2.50, 14.17), and median PFS 2.86 months (95%CI 2.34, 6.05) (Figure 1). 6 pts underwent ASCT consolidation after TIER, of whom 2 have relapsed. CONCLUSIONS This is an early analysis of data from the phase I/II TIER study for a heavily pre-treated group of r/r PCNSL; the first such dose-escalation study for this patient group. Phase I determined a RP2D of 50mg/m2 of thiotepa incorporated in the R-IE regimen. There were no DLTs and toxicities, consistent with an intensive ifosphamide-based regimen. ORR was 10 pts (37%) with 3 further responses reported after data lock. If confirmed by central review, the primary endpoint of activity (ORR 40%) will have been reached. However, notwithstanding the response endpoint, most pts experienced very poor survival outcomes. These data describe the feasibility of TIER as a salvage regimen for r/r PCNSL but question the utility of this approach as a standard option, given the short PFS and OS times, except for the minority of pts who received ASCT. Biological and imaging sub studies are underway to identify predictors of outcome. In the modern era of effective first line immunochemotherapy approaches, pts with r/r PCNSL remain a major area of unmet need for whom novel experimental approaches are urgently required. Disclosures Fox: Gilead: Consultancy; AbbVie: Consultancy; Janssen: Consultancy; Celgene: Consultancy; Sunesis: Consultancy; Takeda Pharmaceuticals: Consultancy; Atara Biotherapeutics: Consultancy; Adienne: Other: Travel Support. Martinez-Calle:ABBVIE: Other: Travel support. Collins:Gilead: Consultancy, Honoraria. Ferreri:Novartis: Consultancy; Celgene: Consultancy, Research Funding; Roche: Research Funding; Kite: Consultancy. Davies:BioInvent: Research Funding; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Honoraria, Research Funding; Karyopharma: Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Honoraria, Research Funding; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Acerta Pharma: Honoraria, Research Funding; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; GSK: Research Funding; Bayer: Research Funding; ADCT Therapeutics: Honoraria, Research Funding; Kite Pharma: Membership on an entity's Board of Directors or advisory committees; MorphoSys AG: Honoraria, Membership on an entity's Board of Directors or advisory committees. Johnson:Roche: Consultancy, Honoraria, Speakers Bureau; Takeda: Other: Travel, accomodations, expenses. Cwynarski:Adienne: Consultancy; Takeda: Consultancy, Other: conference and travel support , Speakers Bureau; Roche,: Consultancy, Other: conference and travel support, Speakers Bureau; Autolus: Consultancy; KITE: Consultancy; Gilead: Consultancy, Other: conference and travel support, Speakers Bureau; Celgene: Consultancy; Atara: Consultancy; Janssen: Other: conference and travel support, Speakers Bureau.

Description: Background After European Medicines Agency (EMA) approval of axicabtagene ciloleucel and tisagenlecleucel for the treatment of relapsed/refractory (r/r) high-grade lymphoma in 2018, England was one of the first European countries granting fully funded access to these CD19 CAR-T therapies. Both products are available through the National Health Service England (NHSE) Cancer Drug Fund until their cost-effectiveness has been determined. The NHSE CAR-T program has been set up in a structure aiming to implement robust and transparent criteria for patient selection and to ensure equity of treatment access: CAR-T slots are approved by a weekly National CAR-T Clinical Panel (NCCP), consisting of independent clinical experts, patient representatives, and delegates from each CAR-T centre; treatment is delivered in 7 geographically spread commissioned CAR-T centres (Birmingham, Bristol, King's College Hospital London, University Hospital London, The Christie Manchester, Manchester Royal Infirmary, Newcastle). Here, we report prospective data on the first 122 lymphoma patients approved by the NCCP. Methods Patients with r/r high-grade lymphoma referred to the NCCP between December 2018 and July 2019 and deemed eligible for treatment with CD19 CAR-T were analysed. Eligibility was assessed in the CAR-T centre's tumor board, based on organ function and fitness (performance status 0/1), absence of active CNS disease, and biopsy confirmation of r/r high-grade lymphoma. The final decision on patient eligibility was made by consensus through the NCCP independent clinical panel. CAR-T product selection for each patient was done by the CAR-T centre, mainly on the basis of manufacturing slot availability. Results 122 patients were approved for treatment with CD19 CAR-T therapy by the panel. CAR-T centres selected 76 patients for axicabtagene ciloleucel and 46 for tisagenlecleucel. Patients' median age was 56 years (range 18-75). 62% were male. 87 (71%) patients had de novo diffuse large B-cell lymphoma, 29 (24%) transformed lymphoma (23 from follicular- and 6 from marginal zone lymphoma), and 6 (5%) primary mediastinal B-cell lymphoma. 96 (79%) patients had biopsy confirmation of disease prior to submission. 71 (58%) patients had received 2 prior lines of therapy for high-grade lymphoma, 51 (42%) patients 3 or more treatment lines (maximum 6). 5 patients had previous allogeneic, 19 previous autologous transplant. 88% of patients (107/122) were refractory to the last line of treatment (stable- or progressive disease (PD) or relapse within 6 months). Among 122 patients, 112 completed leukapheresis, 3 are awaiting the procedure, and 7 patients did not proceed (6 due to PD, 1 opted for radical radiotherapy). 57 of 112 patients were infused at the time of abstract submission, 42 are awaiting CAR-T infusion. 10 patients did not proceed to infusion due to disease progression and clinical deterioration (3 with CNS relapse), 2 due to manufacturing failure. One patient achieved a complete response following bridging therapy and is currently monitored. 84% (88/105) patients received bridging therapy between the time of NCCP approval and CAR-T infusion (median 64 days), 62 had chemotherapy, 9 radiotherapy, and 17 steroids only. Details on bridging therapy, treatment-related toxicities and outcomes will be provided at the meeting, by which time approximately 62 patients will have completed their 3 months PET response assessment. Conclusion NHSE has successfully implemented a national structure for providing licenced CAR-T products in England, enabling equity of access and oversight on capacity and patient outcomes, which can serve as a model for newly licenced, cost-intense and complex cell- and gene therapies in the future. The prospective and centralised nature of this dataset offers a true reflection of the real-world patient population undergoing CAR-T therapy in England. Disclosures Kuhnl: Kite Gilead: Honoraria. Roddie:Gilead: Consultancy, Speakers Bureau; Celgene: Consultancy, Speakers Bureau; Novartis: Consultancy. Menne:Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Kite/Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel grant, Research Funding, Speakers Bureau; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Bayer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel grant, Research Funding, Speakers Bureau; Kyowa Kirin: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel grant, Research Funding, Speakers Bureau; Daiichi Sankyo: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel grant, Research Funding, Speakers Bureau; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Astra Zeneca: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel grant; Jazz: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel grant, Research Funding, Speakers Bureau; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel grant, Research Funding, Speakers Bureau. Sanderson:Kite/Gilead: Honoraria. Osborne:Novartis: Other: Travel; Pfizer: Honoraria, Speakers Bureau; MSD: Consultancy; Takeda: Consultancy, Honoraria, Other: Travel, Speakers Bureau; Roche: Consultancy, Honoraria, Other: Travel, Speakers Bureau; Servier: Consultancy; Gilead: Consultancy. Radford:AstraZeneca: Equity Ownership, Research Funding; Takeda: Consultancy, Honoraria, Research Funding; BMS: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; ADC Therapeutics: Consultancy, Research Funding; GSK: Equity Ownership; Seattle Genetics: Consultancy, Honoraria. Patten:Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilead: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria; Roche: Honoraria, Research Funding. O'Reilly:Kite Gilead: Honoraria. Bloor:Abvie, Gilead, Novartis, Autolus, Celgene, etc: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Educational grant. Rowntree:Novartis: Consultancy. Bowles:Abbvie: Research Funding; Janssen: Research Funding. Collins:Gilead: Consultancy, Honoraria. McMillan:BMS: Honoraria; Celgene: Honoraria, Speakers Bureau; F. Hoffmann-La Roche Ltd: Honoraria, Speakers Bureau; Gilead: Honoraria; Novartis: Honoraria; Sandoz: Honoraria; Pfizer: Honoraria, Research Funding; MSD: Honoraria.

Description: Introduction: CD20-specific monoclonal antibodies (mAbs) have demonstrated efficacy in the treatment of B-cell non-Hodgkin lymphomas (B-NHL); however, a significant proportion of patients (pts) present with refractory disease or will experience relapse. GEN3013 (DuoBody®-CD3×CD20) is the first subcutaneously administered IgG1 bispecific antibody (bsAb) that targets the T-cell surface antigen CD3 and the B-cell surface antigen CD20, triggering T-cell-mediated killing of B cells. In vitro, GEN3013 efficiently activates and induces cytotoxic activity of CD4+ and CD8+ T cells in the presence of B cells (Hiemstra et al. Blood 2018), and results in long-lasting depletion of B cells in cynomolgus monkeys. Subcutaneous (SC) GEN3013 in cynomolgus monkeys resulted in lower plasma cytokine levels, and similar bioavailability and B-cell depletion, compared with intravenous administration. GEN3013 has higher potency in vitro than most other CD3×CD20 bsAbs in clinical development (Hiemstra et al. HemaSphere 2019). SC GEN3013 in pts with B-NHL is being evaluated in a first-in-human, Phase 1/2 trial (NCT03625037), which comprises a dose-escalation part and a dose-expansion part. Here we report preliminary dose-escalation data. Methods: Pts with CD20+ B-NHL with relapsed, progressive, or refractory disease following anti-CD20 mAb treatment, and ECOG PS 0-2 were included. During dose escalation, pts received SC GEN3013 flat dose in 28-day cycles (q1w: cycle 1-2; q2w: cycle 3-6; q4w thereafter) until disease progression or unacceptable toxicity. Risk of cytokine release syndrome (CRS) was mitigated with the use of a priming dose and premedication with corticosteroids, antihistamines, and antipyretics. Primary endpoints were adverse events (AEs) and dose-limiting toxicities (DLTs). Secondary endpoints included pharmacokinetics (PK), immunogenicity (anti-drug antibodies [ADA]), pharmacodynamics (PD) (cytokine measures; laboratory parameters), and anti-tumor activity (tumor size reduction; objective and best response). Results: At data cut-off (June 28, 2019), 18 pts were enrolled into the dose-escalation part of the trial, with safety data available for pts receiving doses starting at 4 µg. Most pts had diffuse large B-cell lymphoma (DLBCL; n=14) and were heavily pre-treated; 10 pts had received ≥3 prior lines of therapy (overall median [range]: 3 [1-11]). The median age was 58.5 years (range: 21-80), and 13 pts were male. At a median follow-up of 1.9 months, pts received a median of 5 doses (range: 1-14); treatment is ongoing in 6 pts. Twelve pts discontinued treatment due to progressive disease. Six pts died (2 during treatment, 4 during survival follow-up), all due to disease progression and unrelated to treatment. The most common (n≥5) treatment-emergent AEs were pyrexia (n=8), local injection-site reactions (n=7), diarrhea (n=5), fatigue (n=5), and increased aspartate aminotransferase (n=5). The most common Grade (G) 3/4 AEs were anemia (n=3) and neutropenia (n=3). Despite increasing GEN3013 doses, all CRS events were non-severe (initial observation: 3/8 pts, G1: n=1, G2: n=2; following modification of premedication plan [corticosteroids for 3 days]: 6/10 pts, G1: n=4, G2: n=2). Increases in peripheral cytokine (IL6, IL8, IL10, IFNγ, TNFα) concentrations after GEN3013 dosing correlated with clinical symptoms of CRS in most pts. No pts had tumor lysis syndrome or neurological symptoms. No DLTs were observed. GEN3013 PK profiles reflect SC dosing; Cmax occurred 2-4 days after dosing. No ADAs were detected. PD effects following GEN3013 dosing were observed at dose levels as low as 40 µg and included rapid, complete depletion of circulating B cells (if present after prior anti-CD20 therapy) and peripheral T-cell activation and expansion. The first evidence of clinical activity was observed at a dose level of 120 µg, with complete metabolic response observed in a pt with DLBCL. Conclusions: Subcutaneously administered GEN3013, a potent CD3×CD20 bsAb, shows good tolerability and early evidence of clinical activity at low dose levels in heavily pretreated pts with relapsed or refractory B-NHL. All CRS events were non-severe and did not lead to discontinuation. No DLTs were observed. Dose escalation is ongoing; updated data will be presented. Dose expansion will begin upon determining the recommended Phase 2 dose (RP2D) (NCT03625037). Disclosures Lugtenburg: Janssen Cilag: Honoraria; Roche: Consultancy, Honoraria, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria; Servier: Consultancy, Honoraria, Research Funding; Genmab: Consultancy, Honoraria; BMS: Consultancy; Takeda: Consultancy, Honoraria, Research Funding. Mous:Bristol-Myers Squibb: Honoraria; Celgene: Honoraria; Sandoz: Honoraria; Roche: Honoraria; Abbvie: Honoraria; Takeda: Honoraria, Research Funding; Janssen Cilag: Consultancy, Honoraria; MSD: Honoraria; Gilead: Consultancy, Honoraria, Research Funding. Clausen:Abbvie: Other: Travel grant to attend ASH 2019. Johnson:Boehringer Ingelheim: Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Celgene: Honoraria; Epizyme: Honoraria, Research Funding; Incyte: Honoraria; Takeda: Honoraria; Genmab: Honoraria; Bristol-Myers Squibb: Honoraria; Kite: Honoraria; Novartis: Honoraria. Rule:Janssen: Consultancy, Honoraria, Research Funding; Roche: Consultancy, Honoraria, Research Funding; Astra-Zeneca: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Pharmacyclics: Consultancy, Honoraria; Gilead: Consultancy, Honoraria; Sunesis: Consultancy, Honoraria; TG Therapeutics: Consultancy, Honoraria; Napp: Consultancy; Kite: Consultancy. Oliveri:Genmab: Employment, Equity Ownership. DeMarco:Genmab: Employment, Equity Ownership. Hiemstra:Genmab: Employment, Equity Ownership, Other: Warrants. Chen:Genmab: Employment. Azaryan:Genmab: Employment. Gupta:Genmab: Employment, Equity Ownership. Ahmadi:Genmab Inc: Employment, Other: stock and/or warrants. Hutchings:Incyte: Research Funding; Roche: 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, Research Funding; Novartis: Research Funding; Genmab: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Research Funding; Janssen: Research Funding; Pfizer: Research Funding.

Description: Background: Despite numerous treatment (Tx) options, follicular lymphoma (FL) remains incurable, and established common treatments such as chemoimmunotherapy combinations and kinase inhibitors can have significant morbidity, especially in older patients or in those with comorbidities. G100 is a TLR4 (toll-like receptor 4) agonist that activates both the innate and adaptive arms of the immune system. When given intratumorally (IT), G100 triggers an anti-tumor immune response that leads to systemic tumor shrinkage (Flowers ASCO 2017). Initial data from a randomized study of the combination of G100 and pembrolizumab (P) demonstrated that the addition of P resulted in more PRs, abscopal tumor shrinkage, and a trend to a better PFS than G100 alone. In addition, an association between baseline tumor TLR4 expression by immunohistochemistry (IHC) and clinical response was observed (Flowers ASH 2017). We now present updated response data and long-term follow-up of this randomized study. Methods: Previously treated or Tx naïve FL pts with ≥2 tumor sites were eligible. Pts received 6-9 doses of IT G100 (G) weekly to a site treated with low dose radiation (RT, 2 Gy x2 doses). A 2nd course of G could be given without additional RT to an additional site. Pts were randomized to IT G (10 µg/dose) or IT G + P 200mg IV on Day 14 then q3wks for up to 2 years. Responses were evaluated by IrRC criteria based on bidimensional measurements (Wolchok ClCanRes 2009). Untreated sites were followed for abscopal response. Results: As of 3July2018, 26 FL pts were treated (13, G vs. 13, G + P). 7 and 5 pts were Relapsed/Refractory (R/R) in G and G+P, respectively. Median number of prior therapies were 3 for G and 4 for G+P and included 5pts previously Tx with auto-SCT. Median duration of observation was 14.3 and 16.6 mos for the G and G+P, respectively. G was well tolerated; related AEs were all grade (Gr) 1/ 2 with no G-related DLTs or SAEs. For G+P, 1 pt experienced Gr 2 hypothyroidism and 1pt, Gr 3 colitis/lab abnormalities/adrenal insufficiency (SAE). No deaths were reported. Overall best responses (PRs) were: 23% in pts on G and 54% in pts on G+P. In the R/R population, PRs occurred in 29% of pts on G and in 80% of pts on G+P. Median time to response was 2.3 mos (range 1.7-18.1) for G and 3.7 mos (range 2.2-17.1) for G+P, and included delayed responses at ≥18mos. Among pts with baseline TLR4high (≥50%) tumor expression, ORR was 17% for G (n=6) vs 75% for G+P (n=8). Within the GELF high tumor burden pts, PRs occurred in 0% of pts in G and in 33% of pts in G+P. Likewise, in pts failing R-Chemo

Description: INTRODUCTION Primary central nervous system lymphoma (PCNSL) in patients (pts) over 65 years old have poorer outcome compared to younger cohorts, as comorbidities, baseline performance status and susceptibility to iatrogenic toxicity impede adequate drug delivery (Kasenda et al, Ann Oncol, 2015). Balancing toxicity against treatment benefits remains a challenge in this age group. Recent trials have attempted to rationalize treatment aiming for reduced toxicity whilst maintaining CNS penetration. Efficacy of additional agents, such as oral alkylators (Fritsch et al, Leukemia 2017) has also been demonstrated. Most clinical trial cohorts underrepresent elderly pts and thus analysis of real-world outcomes and therapeutic practice is warranted. METHODS Consecutively diagnosed pts between 01/10/12 and 01/10/17, ≥65 years old in 14 tertiary UK centres were analysed retrospectively. Radiological exclusion of systemic disease and histological diagnosis were mandatory. Pts receiving any form of 1st line treatment including palliative (whole-brain radiotherapy [WBRT]/oral chemotherapy), best supportive care (BSC) or clinical trial were included. Diagnostic and referral pathways were audited. Baseline patient characteristics and treatment received was recorded in order to document current UK practice. Pts. were stratified into 4 treatment groups: single agent MTX; MTX with oral alkylator; high-intensity HI-MTX (MTX/AraC and MATRix) or palliative intent treatment (WBRT/oral alkylator/BSC). The study primary outcome was overall response rate (ORR) after induction. Secondary outcomes were PFS and OS. Additional variables were MTX clearance and the relative dose intensity (RDI) of MTX normalised with a reference of 14mg/m2. UV/MVA for ORR and Cox-regression for PFS and OS were used for identification of baseline predictors of response and survival. RESULTS 244 pts were included in the analysis with median age 71yrs (range 65-91) and 123 (50%) male. LDH (Elevated:104, 42%) and ECOG performance score (PS) (3-4: 87, 36%) were the only prognostic markers recorded. Median time from presenting scan to treatment was 33 days (IQR 22-48). Demographic characteristics are summarised in table 1. 80% of pts (n=192) received MTX based chemotherapy. 68% of pts 〉70yr and 50% 〉75yr received 〉1 cycle of MTX. MTX median cumulative dose delivered was 10.6 g/m2 (range 1.5-21), median number of cycles was 4 (range 1-6). Dose reductions of MTX occurred in 53/176 pts. (30%). Median time to MTX clearance was 3 days (range 1-18) and median RDI was 0.75 (range 0.11-1.5). TRM for MTX treated pts was 7.2%. 112 pts received rituximab (46%; 11% pre-2015 vs. 64% post-2015). 73 pts. (38%) received 3 cycles of HI-MTX and underwent consolidation experienced comparable outcomes to younger trial cohorts. MTX combination chemotherapy and MTX dose intensity were the strongest predictors of survival whilst rituximab was not a covariate for response or survival despite an increase in its use. Maximising cumulative MTX dose, particularly within more intensive protocols, may translate into improved ORR and survival in older pts with PCNSL. Table. Table. Disclosures Kassam: AbbVie: Equity Ownership. Culligan:Merck Sharp & Dohme (MSD): Honoraria; Celgene: Other: Support to attend conferences; Daiichi-Sankyo: Other: Support to attend conferences; JAZZ: Honoraria; Abbvie: Other: Support to attend conferences; Takeda: Honoraria, Other: Support to attend conferences; Pfizer: Honoraria. McKay:Epizyme: Consultancy, Honoraria. Eyre:Roche: Consultancy; Janssen: Consultancy, Other: travel support; Gilead: Consultancy, Other: travel support; Abbvie: Consultancy, Other: travel support; Celgene: Other: travel support. Osborne:Roche: Consultancy, Honoraria, Speakers Bureau; Pfizer: Honoraria, Speakers Bureau; Servier: Consultancy; MSD: Consultancy; Celgene: Consultancy; Takeda: Consultancy, Honoraria, Speakers Bureau; Novartis: Other: Travel to conference. Yallop:Servier: Other: Travel funding; Pfizer: Consultancy. Fox:Janssen: Consultancy, Other: Personal fees and non-financial support, Speakers Bureau; AbbVie: Consultancy, Other: Travel support, Research Funding, Speakers Bureau; Celgene: Consultancy, Other: Travel support, Speakers Bureau; Sunesis: Consultancy; Roche: Consultancy, Other: Travel support, Research Funding, Speakers Bureau; Gilead: Consultancy, Other: Travel support, Research Funding, Speakers Bureau. Cwynarski:Roche: Consultancy, Other: Conferences/Travel support, Speakers Bureau; Autolus: Consultancy; Kite: Consultancy; Gilead: Consultancy, Other: Conferences/Travel support, Speakers Bureau; Janssen: Other: Conferences/Travel support.