The antibody-drug conjugate polatuzumab vedotin (pola) has recently been approved in combination with bendamustine and rituximab (pola-BR) for patients with refractory or relapsed (r/r) large B-cell lymphoma (LBCL). To investigate the efficacy of pola-BR in a real-world setting, we retrospectively analyzed 105 patients with LBCL who were treated in 26 German centers under the national compassionate use program. Fifty-four patients received pola as a salvage treatment and 51 patients were treated with pola with the intention to bridge to chimeric antigen receptor (CAR) T-cell therapy (n = 41) or allogeneic hematopoietic cell transplantation (n = 10). Notably, patients in the salvage and bridging cohort had received a median of 3 prior treatment lines. In the salvage cohort, the best overall response rate was 48.1%. The 6-month progression-free survival and overall survival (OS) was 27.7% and 49.6%, respectively. In the bridging cohort, 51.2% of patients could be successfully bridged with pola to the intended CAR T-cell therapy. The combination of pola bridging and successful CAR T-cell therapy resulted in a 6-month OS of 77.9% calculated from pola initiation. Pola vedotin-rituximab without a chemotherapy backbone demonstrated encouraging overall response rates up to 40%, highlighting both an appropriate alternative for patients unsuitable for chemotherapy and a new treatment option for bridging before leukapheresis in patients intended for CAR T-cell therapy. Furthermore, 7 of 12 patients with previous failure of CAR T-cell therapy responded to a pola-containing regimen. These findings suggest that pola may serve as effective salvage and bridging treatment of r/r LBCL patients.

494 Several randomised pediatric trials have demonstrated that intensification of Asparaginase (ASP) treatment in ALL can contribute to improved outcome. In adult ALL few data are availabe and optimal ASP preparation, schedule and intensity with respect to efficacy and tolerability have to be defined. The optimisation of ASP treatment is therefore an essential aim of the GMALL. Treatment: Induction treatment of the ongoing study 07/2003 consists of dexamethasone, vincristine, daunorubicine, pegylated asparaginase (PEG-ASP) (phase I), mercaptopurine, cyclophosphamide and cytarabine (phase II) as previously described (Brueggemann et al, Blood 2006: 107; 1116). During the study the dose for PEG-ASP was increased from 1000 to 2000 U/m2 in induction and from 500 to 2000 U/m2 in consolidation (combined with HDMTX and MP) for pts aged between 15 and 55 years. 1 application for high risk and 7 applications for standard risk (SR) were scheduled during the first year and the aim was improvement of overall survival (OS) and remission duration (RD). Patients: From more than 100 centers in Germany 1226 pts with a median age of 35 (15-55) yrs were evaluable. 826 pts were treated with 1000 U/m2 (cohort 1) and 400 pts with 2000 U/m2 (cohort 2) and both groups were comparable regarding major entry criteria. The analysis was restricted to pts who received one of the scheduled PEG-ASP doses during induction. Outcome: CR rate after induction was 91% vs 91% in cohort 1 and 2 resp., with comparable rates for early death (4% vs 5%) and failure (5% vs 4%). Data on molecular response (MRD below 10−4) after induction are available in a subset and showed no difference between both cohorts after induction (79% vs 82%). OS after 3 years was improved in cohort 2 (60% vs 67%; p>.05). The positive effect was specifically evident in SR patients (N=407 vs 190) with respect to OS (68% vs 80%; p=.02) and RD (61% vs 74%; p=.02). It was demonstrated in younger pts (15-45 yrs) (71% vs 82%; p=.02) and older pt (45-55 yrs) (56% vs 74%; p>.05). Excellent results were achieved in young adults (15-25 years) with respect to OS (77% vs 86%; p>.05) and RD (60% vs 78%; p>.05). Toxicity: The analysis of toxicity was focused on grade III-IV events during induction with potential correlation to PEG-ASP (764/382 pts in cohort 1/cohort 2)). Incidences are as follows: GOT or GPT (30%/30%), bilirubine (10%/16%), thrombosis (5%/5%) and hypersensitivity (<1%/<1%). In a subset of pts additional AEs were assessed as amylase (5%/13%), lipase (23%/15%) and glucose (10%/12%). Significantly less toxicity was observed during consolidation cycles. Bilirubine °III/IV occurred median 16d after PEG-ASP during phase II of induction. In univariate analysis it was correlated to dose (10% vs 16%; p=.004), age <> 45 yrs (11% vs 17%; p=.005), BMI <> 30 (12% vs 18%; p=.04) and rituximab application (11% vs 18%; p=.009). Hepatomegaly, infections or imatinib application had no significant effect. In multivariate analysis dose and age remained independent significant prognostic factors. Bilirubine increase during induction was associated with treatment delays and inferior prognosis. Conclusions: This is the largest cohort of adult ALL treated with PEG-ASP. Due to prolonged activity fewer applications are required which is a pre-requisite for realisation of ASP intensification in the context of an intensive multidrug chemotherapy for adult ALL. Although CR rate and molecular CR were not significantly improved PEG-ASP intensification was associated with an improved OS and RD. The improvement was specifically evident in SR pts treated with up to 7 doses of PEG-ASP. Overall intensified PEG-ASP was feasible. The rate of grade III-IV bilirubine elevation increased after dose escalation and led to treatment delays in individual pts which were prognostically relevant. It would be an important goal to identify parameters to predict severe ASP related toxicity. Further intensification of ASP by additional applications would be of interest. Supported by Deutsche Krebshilfe 70–2657-Ho2 and partly BMBF 01GI 9971 and Medac GmbH. Disclosures: Goekbuget: Medac: Consultancy, Research Funding, Speakers Bureau. Hoelzer: Medac: Speakers Bureau.

1493 Few older ALL pts are entered into prospective trials and data on characteristics and outcome are scarce. The GMALL started a prospective trial in older ALL (>55 yrs) in 2003. In Ph-neg ALL a prephase (Dexa, Cyclo, MTX i.th.) was followed by induction I (Dexa, VCR, Idarubicin), induction II (Cyclo, AraC), alternating consolidation with IDMTX (d 1,15) ×3, VM26/AraC ×2, reinduction (VCR, Ida, Cyclo, AraC) and maintenance (MP, MTX) up to 2 yrs. In CD20+ ALL Rituximab ×8 was added. CNS-prophylaxis consisted of i.th. triple combination (MTX, AraC, Dexa) ×4 during induction, ×8 during consolidation/maintenance. The original protocol (group 1) was amended to optimize CNS prophylaxis and consolidation (group 2). I.th. therapy was then performed with liposomal cytarabine, 3x during induction, 3x during consolidation. IDMTX dose was increased from 500 to 1000 mg/m2 and native E.coli ASP (10.000 U/m2) was added on d2 and d16 of IDMTX. VM26/AraC was replaced by IDAraC (1000 mg/m2 d1,3,5). In a further amendment the original i.th. prophylaxis was reinserted until final analysis of liposomal AraC became available. Furthermore, after induction, one cycle with pegylated ASP (500 U/m2) (PEG-ASP) was scheduled to evaluate feasibility in older pts (group 3). Results of induction were compared for groups 1–3; outcome analysis was restricted to 1–2 due to still short follow-up for group 3. 268 pts with a median age of 67 (55–85) yrs treated in 94 hospitals were evaluable (180, 43 and 45 pts in groups 1, 2 and 3 resp.). 39% were aged 55–65 yrs, 51% 66–75 yrs and 10% above 75 yrs. 67% had c/pre-B-ALL, 18% pro-B-ALL and 15% T-ALL. WBC was >30/nL in 27%. Poor ECOG status (≥2) before (ECOGb) or after (ECOGa) onset of ALL was described in 7% or 38% resp. 78% had any comorbidity and 9% had a Charlson score (ChS) ≥3. No significant differences were detected between groups 1–3. Overall 76% (N=203) achieved CR after induction, 14% experienced early death (ED) and 10% did not achieve CR. In groups 1–3 CR rates were 72%, 86% and 82% resp. and ED rates 18%, 0% and 11% resp. (p=.03). CR rates were 84%, 74% and 52% in three age groups (p=.002) with ED rates of 7%, 14% and 37% resp. (p=.0004). Immunophenotype and WBC (<> 30.000) correlated with CR but not ED rate. ECOGb 0–1 vs ≥2 correlated with CR (82% vs 33%;p<.0001) and ED (7% vs 53%;p<.0001). Also ECOGa correlated with CR (85% vs 67%;p=.003) and ED (6% vs 19%;p=.003). CR and ED rates were not influenced by comorbidity itself but by ChS < vs ≥3: CR (78% vs 59%;p=.003) and ED (11% vs 33%;p=.0007). Multivariate analysis confirmed ECOGb, WBC and age for CR rate, and ECOGb, age and ChS for ED. Overall survival (OS) at 5 yrs was 23%; 33% at 2 yrs for group 1 and 52% for group 2 resp. (p=.01). Mortality in CR was 6% and 15% of the pts were withdrawn in CR. Probability of continuous complete remission (CCR) was 32% at 5 yrs, 42% and 43% at 2 yrs for group 1 and group 2 resp. (p=>.05). Age (42% vs 37% vs 8%;p=.0007), WBC (43% vs 15%;p<.0006), ECOGb (40% vs 14%;p=.0008) and ECOGa (42% vs 30%;p=.0023) were correlated with OS in contrast to comorbidity and ChS. Age, treatment group, WBC, ECOGb and ECOGa were confirmed in multivariate analysis. Pts younger than 75 yrs with ECOGb below 2 had an 86% CR rate with 10% ED and 36% OS at 3 yrs. WBC and MRD were significant prognostic factors for CCR. MRD results after consolidation I were available in 33 pts. CCR was 11% in molecular failure vs 68% in molecular CR. Preliminary results confirmed feasibility of PEG-ASP. With this age adapted regimen a favorable CR rate was achieved in a large patient group with a median age of 67 yrs. CR was increased (86%) and mortality was decreased (0%) significantly with liposomal cytarabine compared to triple i.th. prophylaxis during induction, since the latter probably induced more bone marrow toxicity. Reduced ED contributed considerably to improved OS. Moderate intensive consolidation was feasible and ASP, including PEG-ASP, was well tolerated. Age was correlated with outcome and 75 yrs appears to be the upper limit for this regimen. General condition was an additional highly relevant prognostic factor whereas comorbidity, measured by Charlson score was associated with ED but not with OS. These results encourage further treatment optimisation in older ALL pts, including those with comorbidities, based on comprehensive diagnostics, geriatric assessment, MRD evaluation, intensified consolidation, use of ASP, dose-reduced stem cell transplantation and integration of new, targeted drugs. Disclosures: Goekbuget: Medac: Consultancy, Research Funding, Speakers Bureau; Novartis: Research Funding; BMS: Research Funding; Genzyme: Research Funding; Mundipharma: Research Funding, Speakers Bureau; Glaxo: Research Funding, Speakers Bureau; Micromet/AMGEN: Consultancy; Sigma Tau: Consultancy. Off Label Use: Liposomal cytarabine in prophylaxsis of CNS relapse in ALL.

170 The effect of Rituximab in conjunction with a chemo induction and consolidation therapy was studied in CD20+, Ph/BCR-ABL negative B-precursor ALL (Pre-B/Common) in the GMALL Study 07/2003. The rationale were encouraging results with combined intensive chemotherapy and Rituximab in CD20+ adult Burkitt lymphoma / leukemia. Furthermore that in previous GMALL studies, improvement of B-precursor ALL by intensification of chemotherapy was limited and the observation that patients with CD20+ cells (antigen expression >20%) had an inferior outcome in adult ALL (Thomas et al. Blood 2009. 113;6330). Aim: In standard risk (SR) patients the aim was to increase the rate of molecular remission (Mol. CR) thereby decreasing the relapse rate and in high risk (HR) patients to reduce the pre-transplant tumour-load and thereby reducing the relapse rate after SCT which was 30–40% in previous GMALL studies. Materials and Methods: Adult ALL patients (15 – 55 years) with standard risk B-precursor ALL being CD20 pos. received Rituximab 375 mg/m2 at day -1 before each induction course (phase I and II), the re-induction course and before each of the six consolidations for a total of 8 doses. High Risk patients, defined as WBC > 30.000 and/or late CR > 4 weeks, which are candidates for a stem cell transplantation in CR 1 after wk 16, received Rituximab three times (d -1 ind. I/II and Cons. I) before SCT. Patients receiving Rituximab were compared with earlier CD20+ patients in the GMALL study 07/2003 with identical chemo- and supportive therapy but no Rituximab. MRD method and chemo backbone was described earlier [Brüggemann, Blood 2006: 107;1116]. Results: A total of 263 CD20 pos. patients were analyzed in the GMALL study 07/2003; 196 were SR and 67 HR patients. 181 received Rituximab (R+ arm) and were compared to a cohort of 82 patients earlier recruited without Rituximab (R- arm). In the SR there was no difference in the results of induction therapy with a CR rate of 94 % and 91 % in the R+ vs. R- patients. There was also no difference in ED rate 5% vs. 3% or failure/PR 1% vs. 5%. However, MRD course differed substantially. Decrease in MRD load in the R+ vs. R- arm was faster with a Mol CR (MRD <10-4) rate of 57% vs. 27% at day 24 and of 90% vs. 59% at wk 16. Probability for continuous complete remission (CCR) at 5 years was 80% vs. 47% for R+ vs. R- pts. and for overall survival 71% vs. 57%. In the cohort of 67 HR patients the CR rate for R+ vs. R- was 81% vs. 88% due to a higher rate of failure/PR 12% vs. 8%. The ED rates in the R+ vs. R- arm were 7% vs. 4%. There was a higher Mol CR rate at wk 16 in the R+ arm vs. R- with 64% vs. 40%. Overall survival for HR patients at 5 yrs was 55% vs. 36% in the R+ vs. R- group. When only the HR cohort with SCT in CR1 is considered (in 69 % +R and 90% -R SCT in CR1 were performed) the CCR probability was superior for the R+ vs. R- with 67% vs. 37%, due to a lower relapse rate. Conclusion: Intensive chemo- plus immunotherapy with Rituximab is feasible in adult patients with B-precursor ALL in the context of the GMALL protocol 07/2003. In standard risk patients, the complete remission rate was comparable. There was however a faster and higher Mol. CR rate in the Rituximab cohort, with an improvement in remission duration and overall survival. In high risk patients the Mol. CR rate was also higher in the R+ arm and the relapse rate after SCT lower, but probably more Rituximab doses are needed in this patient cohort to reduce the tumour load before SCT further. Supported by Deutsche Krebshilfe 70–2657-Ho2 and in part by Hoffmann La Roche. Disclosures: Off Label Use: Rituximab: activity against CD20 pos. ALL cells.

8030 Background: The prospective, multicenter international phase II PTLD-1 trial of sequential treatment (ST, 4 cycles of weekly rituximab followed by 4 cycles of CHOP-21 + G-CSF) in adult CD20-positive PTLD demonstrated excellent efficacy (90% overall response rate, ORR) and safety (11% treatment-related mortality, TRM). As the response to rituximab predicted overall survival (OS), the trial was amended in 2007 introducing risk-stratified sequential treatment (RSST) according to the response to rituximab (NCT00590447). Methods: Following rituximab on days 1, 8, 15 and 22, RSST consisted of 4 3-weekly courses of rituximab monotherapy for patients (pts) in complete remission (CR, low risk) while all others (high risk) received 4 cycles of R-CHOP-21 + G-CSF. Key exclusion criteria were CNS involvement, HIV infection, severe organ dysfunction not related to PTLD, and ECOG > 2. Primary endpoint was ORR. This is an analysis of the first 91 patients treated with RSST. Results: 79/91 pts had monomorphic, 12 polymorphic PTLD. 41/91 pts were kidney, 27 liver, 12 heart, 7 lung or heart+lung, 3 heart+kidney and 1 kidney+pancreas transplant recipients. Median age at diagnosis was 60 years (range 20-82). 73/91 pts had late PTLD and 39/85 PTLDs were EBV-associated. 1 pt died before initiation of treatment; 5 pts discontinued treatment after 4 cycles rituximab. TRM of RSST was 7/90 (8%) including 5 deaths with unknown remission status. ORR was thus 74/80 (93%, 95%CI: 84-97%; CR: 62/80 [78%]). 24/90 pts (27%) achieved CR with 4 cycles of rituximab. After a median follow up of >3 years, relapse rate in low risk pts was not increased by rituximab consolidation in RSST compared to CHOP consolidation in ST (3/23 vs. 5/14, p=0.104]). In patients in PD after rituximab, R-CHOP was more effective than CHOP in achieving CR (15/23 vs. 3/11, p=0.038). OS at 3 years was higher with RSST (70%, 95% CI: 60-82%) compared to ST (61%, 95%CI 49-72%) but this difference was not significant. Conclusions: With RSST 27% of pts were classified as low risk and achieved durable tumor control without chemotherapy while R-CHOP seems more efficient than CHOP in in high risk patients.