We designed a phase 1-2 study to evaluate the safety and the efficacy of increasing doses of bendamustine (160 mg/m 2 , 180 mg/m 2 , and 200 mg/m 2 given on days ؊7 and ؊6) coupled with fixed doses of etoposide, cytarabine, and melphalan (BeEAM regimen) as the conditioning regimen to autologous stem cell transplantation for resistant/relapsed lymphoma patients. Forty-three patients (median age, 47 years) with non-Hodgkin (n ‫؍‬ 28) or Hodgkin (n ‫؍‬ 15) lymphoma were consecutively treated. Nine patients entered the phase 1 study; no patients experienced a dose-limiting toxicity. Thirty-four additional patients were then treated in the phase 2. A median number of 6 ؋ 10 6 CD34 ؉ cells/kg (range, 2.4-15.5) were reinfused. All patients engrafted, with a median time to absolute neutrophil count > 0.5 ؋ 10 9 /L of 10 days. The 100-day transplantation-related mortality was 0%.

No abstract

The aim of the study is to evaluate clinical features, treatments and outcome of patients with systemic mast cell disease (MCD) who arrived to the attention of hematologists. A retrospective study was conducted over 1995-2006 in patients admitted in 18 Italian hematological divisions. Twenty-four cases of advanced MCD were collected: 12 aggressive SM (50%), 8 mast cell leukemia (33%), 4 SM with associated clonal non-mast cell-lineage hematologic disease (17%). Spleen and liver were the principal extramedullary organ involved. The c-kit point mutation D816V was found in 13/18 patients in which molecular biology studies were performed (72%). Treatments were very heterogeneous: on the whole Imatinib was administered in 17 patients, alpha-Interferon in 8, 2-CdA in 3; 2 patients underwent allogeneic hematopoietic stem cell transplantation. The overall response rate to Imatinib, the most frequently employed drugs, was of 29%, registering one complete remission and four partial remission; all responsive patients did not present D816V c-kit mutation. Overall three patients (12%) died for progression of disease. We conclude that MCD is characterized by severe mediator-related symptoms but with a moderate mortality rate. D816V c-kit mutation is frequent and associated with resistance against Imatinib. Because of the rarity of these forms, an effective standard of care is lacking. More data are needed to find new and successful therapeutic strategies.

Background and Aims. Minimal residual disease (MRD) detection by PCR-based methods is a relevant outcome predictor in MCL, however it is not clear which might represent the most effective methodology (nested vs real-time quantitative PCR, RQ-PCR), the most informative tissue source (bone marrow, BM, vs peripheral blood, PB), the best timing of analysis (midterm vs post-therapy) and the added value of performing multiple MRD determinations. To address these issues a systematic MRD detection program was performed in the Fondazione Italiana Linfomi (FIL) MCL0208 trial (NCT02354313), a prospective, randomized phase III trial comparing lenalidomide maintenance vs observation after an intensive citarabine containing chemo-immunotherapy (R-HDS) program followed by ASCT in 300 frontline MCL patients <66 years [Cortelazzo EHA2015]. Patients and methods. MRD was assessed with ASO primers on either IGH or BCL-1/IGH rearrangements by both nested and RQ-PCR in a Euro-MRD certified lab, both in PB and BM samples at the following time points (TP): diagnosis, after 3 R-CHOP-21 and R-high-dose cyclophosphamide (R-HD-CTX), after R-high-dose Ara-C (R-HDAC), after ASCT and every six months thereafter. Landmark analysis starting 12 months after consent using Cox models was performed based on MRD negativity at each TP. To evaluate the effect of MRD on PFS and OS, we considered also the whole follow-up (FU) period, including all available MRD evaluations as time-varying covariates, both in a dichotomous (pos vs. neg) and cumulative manner (0, 1, 2 or more consecutive MRD-negative results). Finally, the discrimination ability of MRD vs clinical evaluation after ASCT was assessed in the randomized population in terms of C index. All effects were estimated adjusting for MIPI score. Results. A total of 1476 BM and 1482 PB samples were collected, for a sampling compliance rate of 93%. 250 patients (83%) had a molecular marker and showed higher median baseline tumor infiltration by flow cytometry than no marker patients (BM 8.70% vs 0.35). 231/250 (92%) patients presented at least one FU sample and were thus studied for MRD by nested PCR, while 163/231 (71%) were studied also by RQ-PCR, according to the EuroMRD guidelines. Rates of MRD negativity in BM and PB by nested-PCR, as well as by RQ-PCR, were 29%, 46%, 36% and 49% after R-HD-CTX, 53%, 78%, 73% and 87% after R-HDAC, and 54%, 79%, 81% and 89% after ASCT, respectively. MRD positivity at every TP (either by nested or RQ-PCR, either in BM or PB) showed a two-fold higher risk of relapse or death during the six months following the sampling, independently of MIPI. Remarkably, similar two-fold HRs were recorded in terms of OS, too (Table 1A). In detail, RQ-PCR showed a higher risk increase than nested-PCR, as well as BM than PB. In the landmark analysis we found that the risk of relapse gradually increased, the more MRD negativity occurs later during therapy; actually, compared to patients with MRD response after R-HD-CTX, the HR was 1.24 for MRD responders after R-HDAC, 1.51 after ASCT and 2.04 for patients never achieving MRD response by RQ-PCR in BM (Table 1B). Therefore, 3y-PFS for patients MRD positive vs negative in BM by RQ-PCR was 53% vs 66% (HR=1.57, p=0.033) after R-HD-CTX, 47% vs 64% (HR=1.47, p=0.241) after R-HDAC and 25% vs 66% (HR=2.47, p=0.037) after ASCT. Overall, the PFS discrimination ability of MRD negativity after ASCT was better than the clinical response in terms of C-index (0.67 vs 0.62), according to Cox models including MIPI and randomization arm. Most importantly, the PFS risk seemed to follow a downward trend, according to the accumulation of MRD negative results, independently of the single TP. Actually, the presence of 2 or 3 consecutive MRD negative results conferred a significantly reduced risk of relapse, refining the risk stratification of a single MRD negativity (Table 1C). E.g., focusing on RQ-PCR in BM, the HR for relapse was 0.60 for a single negativity, 0.40 for 2 consecutive negative results and 0.27 for 3 or more. Conclusions. 1) MRD results are predictive both for PFS and OS in MCL; 2) RQ-PCR is the most reliable MRD technique and data derived from BM samples provide the best risk stratification; 3) MRD analysis performed at the TP post R-HD-CTX and post ASCT well describes patients' relapse risk, independently from MIPI, however: 4) a kinetic model, based on the combination of 2 or more MRD TP, provides a powerful risk stratification tool, suitable for MRD-guided treatment. Disclosures Vitolo: Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Sandoz: Speakers Bureau; Gilead: Speakers Bureau; Takeda: Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Roche: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau.

Background. Immunochemotherapy is effective in follicular lymphoma (FL), but most patients (pts) eventually relapse. MRD analysis, based on the detection of Bcl-2/IGH rearrangement by highly sensitive PCR-based tools, is effective in identifying pts at risk of relapse [Ladetto Blood 2012; Pott EHA23]. However, several issues are still unresolved, including: i) which is the best tissue source and the most reliable technique; ii) which are the most predictive time points; iii) which is the role of disease kinetics during the long natural history of FL. The FIL FOLL12 prospective, phase III randomized clinical trial (EudraCT: 2012-003170-60) included a systematic MRD analysis on both peripheral blood (PB) and bone marrow (BM) taken at eight different pre-planned time points, by both nested and real time quantitative (RQ)-PCR. Therefore, it allows addressing these unresolved issues. Methods. The FOLL12 compared conventional rituximab maintenance [Salles et al, Lancet 2010] vs a combined PET/MRD response-based post-induction approach in pts with advanced FL after first line chemo-immunotherapy. Clinical results have been already reported [Luminari et al, ICML16]. PB and BM samples were centralized at four Italian Euro-MRD certified laboratories. MRD was assessed with consensus primers on Bcl-2/IGH rearrangements (MBR, mcr and minor rearrangements) by both nested and RQ-PCR at eight time points: baseline, end of induction (EoI) and every six months thereafter till month 36. MRD data were treated as a time-varying covariate and analyzed by means of flexible parametric survival model (Parmar-Royston) with the log cumulative baseline hazard function. MRD data were modeled with restricted cubic spline as function of time. Effect of fixed covariates and landmark analysis were performed with the Cox PH regression. Any estimation was reported with its 95%CI. Results. Overall, 10,702 analytical results were generated, (3,000 for marker screening and 7,702 for MRD). 780 of 786 eligible pts (99%) were screened at baseline for the presence of a molecular marker. 443/780 (57%) had a detectable Bcl-2/IGH rearrangement, as expected. High rates of MRD negativity were observed at EoI, with similar results by both techniques (87% in BM and 95% in PB by nested-PCR, 90% in BM and 95% in PB with RQ-PCR). Overall, the presence of one MRD positive result was associated during the entire follow-up period with an increased risk of relapse in the subsequent six months interval (HR for PFS 2.82, 95% CI 1.84-4.34, p&lt;0.001), independently from randomization arm (heterogenous test for HR in PFS 0.330), treatment received (HR 0.859) and FLIPI-2 (HR 0.302). Most notably, a sharp increase of HR was observed during follow-up, with time points after 6 and particularly after 12 months or later outperforming the earliest evaluation. Interestingly, very similar results were recorded in BM or PB and using nested or RQ-PCR (Figure 1A). Despite inferior performance compared to later timepoints, MRD positivity in BM at EoI was nevertheless predictive of a shorter 4y-PFS (61% vs 75% by nested-PCR and 54% vs 74% by RQ-PCR, p=0.03 and p=0.003, respectively). Moreover, a kinetic analysis showed that pts scoring MRD+ at EoI but converting to MRD- in the following time points showed superimposable outcome to pts persistently MRD- (HR for PFS 0.66, 95% CI 0.24-1.82, p=0.420), while pts scoring MRD- at EoI but then converting to MRD+ showed a worse outcome (HR for PFS 1.75, 95% CI 1.21-2.53, p=0.003) (Figure 1B). Actually, Kaplan Meier landmark analyses stratified by updated MRD results at each punctual timepoint after EoI were overall highly discriminant in terms of PFS, with PB results (Figure 1C) substantially overlapping BM performances from months 12 after EoI (not shown) and thereafter. Conclusions. This comprehensive MRD study in FL clearly indicates that: i) punctual MRD analysis is predictive of poor outcome at multiple pre-planned time points taken over a 36 months period; ii) both nested and RQ-PCR performed adequately, the latter being preferable as broadly used and internationally standardized; iii) BM allows better prediction at the early time points but, starting from month 12 after EoI PB is superimposable to BM, allowing effective and reliable long-term non-invasive MRD monitoring; iv) the high predictive value of punctual time point analysis is further improved by a kinetic approach to the interpretation of MRD results. Figure 1 Figure 1. Disclosures Ladetto: AbbVie, Jazz, Gentili, Incyte, ADC Therapeutics, Acerta, Pfizer: Honoraria; Roche, J&J, Celgene, Novartis, Amgen, Gilead, Beigene, GSK: Honoraria. Ferrero: Servier: Speakers Bureau; EUSA Pharma: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Morphosys: Research Funding; Incyte: Membership on an entity's Board of Directors or advisory committees; Gilead: Research Funding, Speakers Bureau; Clinigen: Membership on an entity's Board of Directors or advisory committees. Del Giudice: Tolero: Membership on an entity's Board of Directors or advisory committees; Astrazeneca: Membership on an entity's Board of Directors or advisory committees. Galimberti: Incyte: Speakers Bureau; AbbVie, Janssen: Honoraria, Other: Travel grants. Gattei: abbVie: Research Funding; Janssen: Research Funding; Menarini: Research Funding. Mannina: Janssen,Takeda: Membership on an entity's Board of Directors or advisory committees; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees. Falini: Rasna Therapeutics: Honoraria. Luminari: Roche, Celgene, Teva Pharmaceuticals, Gilead Sciences, and Takeda Pharmaceuticals: Honoraria.

The R-BAC regimen is considered among standard first-line treatment for elderly fit patients with mantle cell lymphoma (MCL). In the previous R-BAC500 FIL trial, patients with the blastoid variant and/or high Ki67 proliferative index (High Risk - HR-) had a significantly higher risk of progression (2-years PFS of 40%), as compared to classical histologies and low proliferative index (Low Risk -LR-). When treated with R-BAC, LR patients had excellent outcome (median PFS not reached after 7 years), although no maintenance therapy was delivered. For this reason we designed a phase 2 trial that enrolled patients from 35 centers of the Fondazione Italiana Linfomi (FIL). At study entry, patients were centrally reviewed and stratified as "low risk (LR)", or "high risk (HR)", depending on morphology (blastoid versus others), Ki67 expression (≥30% versus others), TP53 mutation/TP53 deletions (present versus not). Patients with any of the three risk factors were classified as HR. The primary endpoint was 2-years progression-free survival (PFS) for the HR patients. Patients had to be aged ≥65 years and fit according to the geriatric CGA assessment, or age ≤64 years if not eliglible to high-dose chemotherapy plus transplantation. Asymptomatic patients with non-nodal disease were excluded. Treatment consisted of 6 cycles of R-BAC (rituximab 375 mg/m2 d 1; bendamustine 70 mg/m2 d 1,2; cytarabine 500 mg/m2 d 1,2,3) for LR patients. HR patients received abbreviated induction with a maximum of 4 R-BAC followed by consolidation (4 months, 800 mg/d), and maintenance (20 months, 400 mg/d) with venetoclax. First patient was included on the 3rd of september, 2018, and last patient on the 20th of july, 2021. Overall, 140 patients were enrolled, of whom 52 were HR (37%). Median age was 72 (range 57-79), and 75% were males. The prevalence of TP53 mutations and deletions in the whole series was 21%, and 13%, respectively; Ki67 was ≥30% in 24%, and the blastoid variant was diagnosed in 9%. Demographic characteristics of HR versus LR patients (127 patients with available data at the present time) are reported in Table 1A. Median follow-up was 9 months (range 0-34). The two groups (HR and LR) had similar age, gender, and MIPI, but differed for LDH, and SUVmax at diagnosis, both being significantly more elevated in the HR group. The VR-BAC trial represents the first prospective study that stratified patients with MCL to different frontline treatments according to centralized on-time evaluation of the risk profile. We have shown that almost 40% of elderly patients with MCL in need of treatment have HR features. Data on tolerance, and tumor response will be presented at the meeting. Figure 1 Figure 1. Disclosures Tisi: GILEAD: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; BWS: Membership on an entity's Board of Directors or advisory committees; Incyte: Membership on an entity's Board of Directors or advisory committees. Zilioli: Roche, Italfarmaco: Consultancy, Honoraria; MSD, Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations; Takeda: Other: travel expenses, accommodation; Gentili, Takeda, Gilead, Servier: Consultancy, Speakers Bureau. Corradini: AbbVie, ADC Theraputics, Amgen, Celgene, Daiichi Sankyo, Gilead/Kite, GSK, Incyte, Janssen, KyowaKirin, Nerviano Medical Science, Novartis, Roche, Sanofi, Takeda: Honoraria; BMS: Other: Travel and accommodation; Novartis; Gilead; Celgene: Consultancy, Other: Travel and accommodations; Amgen; Takeda; AbbVie: Consultancy, Honoraria, Other: Travel and accommodations; KiowaKirin; Incyte; Daiichi Sankyo; Janssen; F. Hoffman-La Roche; Kite; Servier: Consultancy; Sanofi: Consultancy, Honoraria; Incyte: Consultancy; AbbVie, ADC Theraputics, Amgen, Celgene, Daiichi Sankyo, Gilead/Kite, GSK, Incyte, Janssen, KyowaKirin, Nerviano Medical Science, Novartis, Roche, Sanofi, Takeda: Consultancy; Novartis, Janssen, Celgene, BMS, Takeda, Gilead/Kite, Amgen, AbbVie: Other: travel and accomodations. Musuraca: janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; incyte: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Puccini: Takeda: Membership on an entity's Board of Directors or advisory committees. Cavallo: Servier: Speakers Bureau; ROCHE: Membership on an entity's Board of Directors or advisory committees; Gilead: Speakers Bureau. Merli: EUSA Pharma: Other: Travel, Accomodations, Expenses; Roche: Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accomodations, Expenses; Takeda: Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accomodations, Expenses; MSD: Membership on an entity's Board of Directors or advisory committees; Gilead Science: Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accomodations, Expenses; Janssen: Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accomodations, Expenses; Celgene: Other: Travel, Accomodations, Expenses. Ferreri: PletixaPharm: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: 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, Research Funding; BMS: Research Funding; Beigene: Research Funding; Hutchison Medipharma: Research Funding; ADC Therapeutics: Research Funding; Adienne: Membership on an entity's Board of Directors or advisory committees; Genmab: Research Funding; Amgen: Research Funding; x Incyte: Membership on an entity's Board of Directors or advisory committees; Ospedale San Raffaele srl: Patents & Royalties; Pfizer: Research Funding. Santoro: AstraZeneca: Speakers Bureau; AbbVie: Speakers Bureau; Amgen: Speakers Bureau; Pfizer: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Roche: Speakers Bureau; Sandoz: Speakers Bureau; Eli-Lilly: Speakers Bureau; BMS: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Eisai: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Speakers Bureau; Servier: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Takeda: Speakers Bureau; Sanofi: Consultancy; Arqule: Consultancy, Speakers Bureau; Novartis: Speakers Bureau; Bayer: 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, Speakers Bureau. Zinzani: KYOWA KIRIN: Other, Speakers Bureau; SERVIER: Other: Advisory board, Speakers Bureau; SANDOZ: Other: Advisory board; TG Therapeutics: Other: Advisory board, Speakers Bureau; ROCHE: Other, Speakers Bureau; BMS: Other: Advisory board, Speakers Bureau; TAKEDA: Other: Advisory board, Speakers Bureau; MSD: Consultancy, Other: Advisory board, Speakers Bureau; NOVARTIS: Consultancy, Other, Speakers Bureau; EUSAPHARMA: Consultancy, Other, Speakers Bureau; Beigene: Other, Speakers Bureau; ADC Therap.: Other; Incyte: Other, Speakers Bureau; JANSSEN-CILAG: Other: Advisory board, Speakers Bureau; GILEAD: Other: Advisory board, Speakers Bureau; CELLTRION: Other: Advisory board, Speakers Bureau; VERASTEM: Consultancy, Other: Advisory board, Speakers Bureau. OffLabel Disclosure: Venetoclax is off-label in Italy in mantle cell lymphoma

No abstract

31 Background: BEAM (Carmustine, etoposide, cytarabine, and melphalan) regimen is the most used conditioning regimen before autologous stem cell transplant (ASCT) in lymphoma patients. However, patients receiving BEAM show a significant number of side effects, and relapse rate after transplant is still a matter of concern. Therefore, new regimens with a higher efficacy and a better toxicity profile in comparison to BEAM are highly needed. Aims: We designed a phase I-II study to evaluate the safety and the efficacy of increasing doses of Bendamustine for the conditioning regimen to ASCT for resistant/relapsed lymphoma patients. Methods: Forty-four patients (median age 47 years, range 18–70) with resistant/relapsed non-Hodgkin (29) or Hodgkin (15) lymphoma were consecutively enrolled in the study. The new conditioning regimen consisted of increasing doses of Bendamustine coupled with fixed doses of Etoposide (200mg/m2/day on days -5 to -2), Cytarabine (400mg/m2 on days -5 to -2) and Melphalan (140 mg/m2 on day -1) (BeEAM regimen). Three cohorts of 3 patients each were treated starting with Bendamustine 160 mg/m2/daily given on days -7 and -6. The dose of Bendamustine was then escalated according to the Fibonacci's increment rule until the onset of severe adverse events and/or the attainment of the expected MTD, but not higher than 200 mg/m2. Patients were carefully monitored for adverse events. The study was registered at EMEA with the EUDRACT no 2008–002736-15. Results: The administration of Bendamustine was safe in all the 3 cohorts of patients. The major side effect was a grade III-IV oral mucositis developed by 9 patients during neutropenia. We then fixed the dose of Bendamustine 200 mg/m2 as safe and effective for the Phase II study. A median number of 5.68×106CD34+/kg cells (range 2.4–15.5) collected from peripheral blood was reinfused to patients. All patients engrafted, with a median time to ANC>0.5×109/l of 10 days. Median times to achieve a platelet count >20×109/l and >50×109/l were 13 and 16 days respectively. Twenty-two out of 44 patients presented a fever of unknown origin (50%). The median number of days with fever was 2 (range: 0–7), with a median number of 9 days of intravenous antibiotics (range: 3–22). All patients received G-CSF after transplant for a median time of 9 days (range: 8–25). Two patients developed a viral infection (1 HSV-6, 1 CMV) early after transplant. Thirty-nine out of 44 patients are evaluable up to now for the response to treatment. All evaluable patients are alive. 32/39 are in complete remission whereas 4/39 are in partial response, after a median follow-up of 11 months from transplant. Three out of 39 patients relapsed after a median time of 3 months from transplant. It is of note that 4/39 patients achieved the first complete remission after receiving the high-dose therapy with autologous stem cell rescue. Conclusions: The new BeEAM regimen is safe and seems to have a high efficacy in heavily pretreated lymphoma patients. Basing on this experience, future studies incorporating Bendamustine in conditioning regimens pre-ASCT in lymphoma patients should use Bendamustine 200 mg/m2/day over 2 days. Acknowledgments: supported in part by AIL Pesaro Onlus. Disclosures: Malerba: celgene, Janssen-Cilag: Honoraria.