Zinzani, Pier Luigi

Abstract Background Several therapies are recommended by NCCN/ESMO guidelines for autologous stem cell transplant (ASCT)-ineligible patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL). In the single-arm, Phase II L-MIND study (NCT02399085), the chemotherapy-free regimen tafasitamab + lenalidomide (LEN) demonstrated efficacy for this patient population. In the absence of randomized clinical trial data, RE-MIND2 (NCT04697160), an observational, retrospective cohort study, compared patient outcomes from L-MIND with matched patient populations treated with NCCN/ESMO recommended therapies for ASCT-ineligible patients with R/R DLBCL. Methods Data were retrospectively collected between 1 April and 13 November 2020 from academic and public hospitals, as well as private practices in North America, Europe and Asia Pacific. To ensure consistency with L-MIND I/E criteria, patients aged ≥18 years with histologically confirmed DLBCL and who had received ≥2 systemic therapies for DLBCL (including ≥1 anti-CD20 therapy) were enrolled. For the main analysis, patients from the L-MIND tafasitamab + LEN cohort were matched with patients from the RE-MIND2 observational cohort using estimated propensity score-based 1:1 nearest neighbor matching, balanced for six baseline characteristics: age (<70 vs ≥70 years), refractoriness to last line of therapy (yes vs no), number of prior lines of therapy (1 vs 2/3), history of primary refractoriness (yes vs no), prior ASCT (yes vs no), and Eastern Cooperative Oncology Group performance status (0-1 vs ≥2). A sensitivity analysis was performed using an inverse probability of treatment weighting method calculating the average effect of the treatment on the treated, to generate balanced cohorts based on nine baseline characteristics: age, refractoriness to last line of therapy, number of previous lines of therapy, history of primary refractoriness, prior ASCT, Ann Arbor Stage (I/II vs III/IV), elevated LDH (yes vs no), neutropenia (yes vs no), and anemia (yes vs no). Additional sensitivity analyses accounting for missing baseline characteristics using multiple imputation technique were performed. Data are presented for tafasitamab + LEN versus polatuzumab vedotin + bendamustine + rituximab (pola-BR), rituximab + LEN (R2), and CD19 CAR-T therapies (CAR-T). The primary endpoint was overall survival (OS). Secondary endpoints included objective response rate (ORR), complete response rate, progression-free survival and duration of response. Results Of 3,454 patients enrolled from 200 sites, 106, 106, and 149 patients were treated with pola-BR, R2, and CAR-T, respectively. For the comparative analysis, matched patient pairs were created using 1:1 nearest neighbor matching with a caliper. Matched pairs consisted of: tafasitamab + LEN vs pola-BR, n=24 pairs; vs R2, n=33 pairs; and vs CAR-T, n=37 pairs. A significant OS benefit was associated with tafasitamab + LEN compared to pola-BR (HR: 0.44, 95% confidence interval [CI]: 0.20-0.96; p=0.038) and R2 (HR=0.44, 95% CI: 0.22-0.84; p=0.014) (Figure 1A-B). There was no significant difference in OS benefit between tafasitamab + LEN and CAR-T (HR=0.95, 95% CI: 0.47-1.91; p=0.891) (Figure 1C). ORR was 62.5% (15/24) for tafasitamab + LEN vs 58.3% (14/24) for pola-BR (p=1.000), 63.6% (21/33) vs 30.3% (10/33) for R2 (p=0.013), and 59.5% (22/37) vs 75.7% (28/37) for CAR-T (p=0.214). Improved outcomes were also observed with tafasitamab + LEN for other secondary endpoints (Table 1). Results are consistent with those obtained in the sensitivity analyses. Conclusions The results of this retrospective cohort analysis suggest that the novel tafasitamab + LEN combination may significantly improve health outcomes, with a prolonged survival benefit for ASCT-ineligible R/R DLBCL patients, relative to NCCN/ESMO recommended therapies. Tafasitamab + LEN improved survival outcomes compared with pola-BR and R2 in closely matched patient populations. Comparable outcomes were observed for tafasitamab + LEN vs CAR-T. Although based on limited patient numbers, these data may be clinically relevant in the context of emerging therapies for R/R DLBCL. While this study design does not replace randomized data, it remains more rigorous than inter-trial comparison. The limitations of comparing clinical trial and matched retrospective real-world data will be discussed. Funding: MorphoSys AG. Figure 1 Figure 1. Disclosures Nowakowski: Celgene, MorphoSys, Genentech, Selvita, Debiopharm Group, Kite/Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene, NanoString Technologies, MorphoSys: Research Funding. Joffe: AstraZeneca. Epizyme: Consultancy. Fleury: Abbvie, Astrazeneca, BMS, Celgene, Janssen, Kite-Gilead, Merck, Novartis, Roche, Seattle Genetics: Other: conference and advisory role. Peters: AbbVie, Incyte: Consultancy, Honoraria. Greil: Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses, Research Funding; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses, Research Funding; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses, Research Funding; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses, Research Funding; Takeda: 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, Other: Travel, Accommodations, Expenses, Research Funding; AstraZeneca: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses, Research Funding; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses; MSD: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses, Research Funding; Gilead: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses, Research Funding; Daiichi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses, Research Funding; Sankyo: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses, Research Funding; Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Merck: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Honoraria, Other: Travel, Accommodations, Expenses, Research Funding; Sandoz: Honoraria, Research Funding. Ku: Roche: Consultancy; Antegene: Consultancy; Genor Biopharma: Consultancy. Marks: Kite/Gilead: Membership on an entity's Board of Directors or advisory committees; AbbVie: Other: Meeting attendance; Kite/Gilead: Honoraria; Merck: Consultancy. Kim: AstraZeneca: Research Funding. Zinzani: BeiGene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Bristol Myers Squibb: 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; EUSA Pharma: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; ADC Therapeutics: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Merck Sharp & Dohme: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celltrion: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Kyowa Kirin: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Verastem: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sandoz: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Incyte: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; TG Therapeutics Inc: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Servier: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen-Cilag: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; ImmuneDesign: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Portola: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Trotman: Beigene: Research Funding; Celgene: Research Funding; Bristol Myers Squibb: Research Funding; Roche: Research Funding; Janssen: Research Funding; PCYC Pharmacyclics: Research Funding. Sabatelli: Incyte: Current Employment, Current equity holder in publicly-traded company. Huang: MorphoSys: Current Employment. Waltl: MorphoSys: Current Employment. Winderlich: MorphoSys: Current Employment, Current equity holder in publicly-traded company. Ambarkhane: MorphoSys: Current Employment, Other: Support for attending meetings/travel. Kurukulasuriya: MorphoSys: Current Employment, Current equity holder in publicly-traded company, Other: Support for attending meetings/travel. Cordoba: Pfizer: Research Funding; Kyowa-Kirin: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AbbVie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; ADCTherapeutics: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Incyte: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Kite: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Hess: Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead/Kite: Research Funding; AstraZeneca: Honoraria, Membership on an entity's Board of Directors or advisory committees; Genmab: Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees; EUSA: Honoraria, Membership on an entity's Board of Directors or advisory committees. Salles: Miltneiy: Consultancy; Novartis: Consultancy; Morphosys: Consultancy, Honoraria; Janssen: Consultancy; Genentech/Roche: Consultancy; Kite/Gilead: Consultancy; Regeneron: Consultancy, Honoraria; Velosbio: Consultancy; Takeda: Consultancy; Allogene: Consultancy; Ipsen: Consultancy; Loxo: Consultancy; Rapt: Consultancy; Genmab: Consultancy; Incyte: Consultancy; Epizyme: Consultancy, Honoraria; Debiopharm: Consultancy; BMS/Celgene: Consultancy; Beigene: Consultancy; Abbvie: Consultancy, Honoraria; Bayer: Honoraria.

Abstract Purpose: Tafasitamab, an Fc-modified, humanized, anti-CD19 monoclonal antibody, in combination with lenalidomide, demonstrated efficacy in transplant-ineligible patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL), in the single-arm, phase II L-MIND study (NCT02399085). RE-MIND, a retrospective observational study, generated a historic control for L-MIND to delineate the contribution of tafasitamab to the efficacy of the combination. Patients and Methods: Data were retrospectively collected from patients with R/R DLBCL treated with lenalidomide monotherapy for comparison with tafasitamab + lenalidomide–treated patients (L-MIND). Key eligibility criteria were aligned with L-MIND. Estimated propensity score–based Nearest Neighbor 1:1 Matching methodology balanced the cohorts for nine prespecified prognostic baseline covariates. The primary endpoint was investigator-assessed best overall response rate (ORR). Secondary endpoints included complete response (CR) rate, progression-free survival (PFS), and overall survival (OS). Results: Data from 490 patients going through lenalidomide monotherapy were collected; 140 qualified for matching with the L-MIND cohort. The primary analysis included 76 patients from each cohort who received a lenalidomide starting dose of 25 mg/day. Cohort baseline covariates were comparable. A significantly better ORR of 67.1% (95% confidence interval, 55.4–77.5) was observed for the combination therapy versus 34.2% (23.7–46.0) for lenalidomide monotherapy [odds ratio, 3.89 (1.90–8.14); P < 0.0001]. Higher CR rates were achieved with combination therapy compared with lenalidomide monotherapy [39.5% (28.4–51.4) vs. 13.2% (6.5–22.9)]. Survival endpoints favored combination therapy. Lenalidomide monotherapy outcomes were similar to previously published data. Conclusions: RE-MIND enabled the estimation of the additional treatment effect achieved by combining tafasitamab with lenalidomide in patients with R/R DLBCL.

Abstract Introduction: The phase 2 CheckMate 205 study (NCT02181738) of nivolumab (nivo) has demonstrated high objective response rates, durable efficacy, and acceptable safety profiles in patients (pts) with relapsed/refractory classical Hodgkin lymphoma (R/R cHL) after failure of autologous hematopoietic cell transplantation (auto-HCT) regardless of prior brentuximab vedotin (BV) treatment (Younes A et al. Lancet Oncol 2016; Fanale M et al. ICML 2017 [Oral 125]). Recently proposed new response criteria aim to account for atypical patterns of response with checkpoint inhibitors which may not be fully captured by conventional response criteria (Cheson BD et al. Blood 2016; Younes A et al, Ann Oncol 2017). Studies in solid tumors have shown that pts may continue to derive clinical benefits from nivo beyond disease progression as defined by conventional criteria (George S et al, JAMA Oncol 2016; Long GV et al, JAMA Oncol 2017). Here we report outcomes among pts with R/R cHL treated beyond progression (TBP) in CheckMate 205. Methods: This single-arm, multicenter study enrolled pts (age ≥18 y) with R/R cHL after failure of auto-HCT into 3 independent cohorts (A: BV naïve, B: BV after auto-HCT, C: BV before and/or after auto-HCT). Nivo 3 mg/kg IV every 2 wk was given until disease progression or unacceptable toxicity. Response was assessed by 2007 International Working Group criteria. Best overall response (BOR) was assessed per investigator. A protocol amendment in July 2014 allowed pts to be TBP (investigator-assessed) if they met prespecified criteria, including deriving clinical benefit, stable performance status, and non-rapid progression. Pts TBP were required to discontinue in the event of further progression (≥10% increase in tumor burden). Tumor burden after initial progression was assessed in a prespecified analysis. Exploratory analyses assessed overall survival (OS) and time to next therapy (TTNT) in pts TBP. Results: In total, 70/243 (29%) pts were TBP: 19 in Cohort A, 23 in B, and 28 in C. Demographics were similar to the overall study population: 57% had stage IV disease at study entry, median (range) age was 37 (18-72) y, and median number of prior therapies was 3 (2-5). BOR prior to progression was complete remission (CR) in 5 (7%) pts, partial remission (PR) in 31 (44%), stable disease (SD) in 20 (29%), and progressive disease in 13 (19%) (BOR was non-evaluable in 1 pt). Among pts TBP, the initial cause of progression was a ≥50% increase in total tumor burden in 13 (19%) pts, non-target lesion progression in 17 (24%), and new lesions in 47 (67%) (pts could have multiple findings as reasons for progression). The median time to initial progression in pts TBP was 6 mo; 11 mo in pts with initial BOR of CR and 7 mo in pts with initial PR or SD. At December 2016 database lock, median (range) doses of nivo beyond progression were 8 (1-43), and median duration of treatment beyond progression was 5 (0-19) mo. Overall, 21 (30%) pts TBP remained on treatment; the most common reason for discontinuation was further disease progression (80%). The majority of pts TBP demonstrated stable reductions in tumor burden with continued treatment. Median (95% CI) TTNT from first study dose of nivo was 17 (14, not estimable) mo (Figure). Median OS from date of initial progression was not reached in pts TBP and OS was 84% (95% CI 70, 92) at 1 y. Treatment-related adverse events (TRAEs) occurred in 46% of pts (13% grade [G] 3-4) after progression, vs 64% (9% G3-4) prior to progression. Serious TRAEs after progression were aspartate aminotransferase increase (n=1) and hypercalcemia (n=1), both G3-4. Ten deaths occurred in pts TBP; 7 were due to disease progression and none were considered related to study drug. Conclusions: In total, 29% of pts from CheckMate 205 Cohort A/B/C were TBP. New lesions were the most common reason for initial progression in pts TBP. Stable reductions in tumor burden were seen with continued treatment in pts TBP, and median TTNT and OS remained high. Proposed updates to response criteria may help to better assess the long-term efficacy of checkpoint inhibitors. These data suggest that pts considered to show stable performance status, non-rapid progression, and clinical benefits despite progression according to conventional response criteria may derive long-term benefits from continued nivo treatment. Study funding: BMS. Writing support: Simon Wigfield, Caudex, funded by BMS. Disclosures Cohen: Bioinvent: Consultancy, Membership on an entity's Board of Directors or advisory committees; Genentech: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takada: Research Funding; Bristol Myers Squibb: Research Funding; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees; Infinity: Consultancy, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; LAM Therapeutics, Inc: Research Funding. Engert: Amgen: Honoraria, Research Funding; Bristol-Myers Squibb: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding; Affimed: Consultancy, Honoraria, Research Funding. Ansell: Merck: Research Funding; Celldex: Research Funding; Seattle Genetics: Research Funding; Bristol-Myers Squibb: Research Funding; Affimed: Research Funding. Younes: Roche: Consultancy, Honoraria, Other: Third-party medical writing assistance, under the direction of Anas Younes, was provided by Scott Malkin of Gardiner-Caldwell Communications, and was funded by F. Hoffmann-La Roche Ltd.; Bayer: Honoraria; Bristol-Myers Squibb: Honoraria; Novartis: Research Funding; Janssen: Honoraria; Merck: Honoraria; Curis: Research Funding; Sanofi: Honoraria; Takeda Millenium: Honoraria; Johnson & Johnson: Research Funding; Seattle Genetics: Honoraria; Incyte: Honoraria; Celgene: Honoraria. Trneny: Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; 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. Savage: Roche: Research Funding; Seattle Genetics: Consultancy, Honoraria; Bristol-Myers Squibb: Honoraria; Merck: Honoraria; Celgene: Consultancy. Ramchandren: Seattle Genetics: Consultancy; Janssen: Research Funding; Merck: Research Funding; Pharmacyclics: Research Funding. Collins: ADC Therapeutics: Research Funding; Roche: Consultancy, Honoraria, Speakers Bureau; Pfizer: Consultancy, Honoraria; Celgene: Research Funding; Celleron: Consultancy; MSD: Consultancy, Honoraria; Takeda: Consultancy, Honoraria, Speakers Bureau; Bristol-Myers Squibb: Research Funding; Amgen: Research Funding. Fanale: AMGEN: Membership on an entity's Board of Directors or advisory committees; CELGENE: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; TAKEDA: Honoraria, Research Funding; ONYX: Research Funding; SEATTLE GENETICS: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; MOLECULAR TEMPLATES: Research Funding; MERCK: Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; GENENTECH: Research Funding; ADC THERAPEUTICS: Research Funding. Armand: Bristol-Myers Squibb: Consultancy, Other: research funding (institutional); Merck: Consultancy, Other: research funding (institutional); Infinity: Consultancy; Pfizer: Consultancy, Other: research funding (institutional); Affimed: Other: research funding (institutional); Otsuka: Other: research funding (institutional); Sequenta: Other: research funding (institutional); Sigma Tau: Other: research funding (institutional); Roche: Other: research funding (institutional); Tensha: Other: research funding (institutional). Zinzani: Bayer: 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; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees; Johnson & Johnson: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Karyopharm Therapeutics: Honoraria, Membership on an entity's Board of Directors or advisory committees; Verastem: Honoraria, Membership on an entity's Board of Directors or advisory committees; Merck: Honoraria, Membership on an entity's Board of Directors or advisory committees; Servier: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees. De Boer: Bristol-Myers Squibb: Membership on an entity's Board of Directors or advisory committees; MSD: Membership on an entity's Board of Directors or advisory committees; Merck: Membership on an entity's Board of Directors or advisory committees, Other: Non-restricted grant for research in head and neck cancer; Eisai: Membership on an entity's Board of Directors or advisory committees; Astellas: Other: member of Independent Data Monitoring Committee. Shipp: Cell Signaling: Honoraria; Bristol-Myers Squibb: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bayer: Research Funding; Takeda: Other: Scientific Advisory Board; Merck: Other: Scientific Advisory Board; Gilead: Other: Scientific Advisory Board; AstraZeneca: Honoraria. Santoro: Merck: Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Membership on an entity's Board of Directors or advisory committees. Timmerman: Seattle Genetics: Consultancy; Celgene: Consultancy; Bristol-Myers Squibb: Consultancy, Honoraria, Other: Travel expenses, Research Funding; Genmab: Consultancy, Equity Ownership; Kite Pharma: Research Funding; ImmuneGene: Research Funding. Sacchi: Bristol-Myers Squibb: Employment. Sy: Bristol-Myers Squibb: Employment. Kuruvilla: BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilead: Consultancy, Honoraria; Janssen: Consultancy; Hoffman LaRoche: Consultancy; Seattle Genetics: Consultancy, Honoraria; Amgen: Honoraria; Roche: Honoraria; Janssen: Honoraria; Lundbeck: Honoraria; Merck: Honoraria; Karyopharm: Research Funding; Roche: Research Funding; Celgene: Honoraria, Research Funding.

Introduction Historically, nearly all relapses in classical Hodgkin lymphoma (cHL) occur within the first 5 years (Radford et al, BMJ 1997). In the phase 3 ECHELON-1 study (NCT01712490), treatment with brentuximab vedotin, doxorubicin, vinblastine, and dacarbazine (A+AVD) significantly improved modified progression-free survival (PFS) in patients (pts) with newly-diagnosed Stage III/IV cHL compared with doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) (Connors et al, NEJM 2018). 3- and 4-year follow-up (Straus et al, Blood 2020; Bartlett et al, Blood 2019) reported durable PFS benefit with A+AVD vs ABVD in the intent-to-treat (ITT) population that was consistent across most key pt subgroups, irrespective of interim positron emission tomography (PET) scan status, disease stage, and baseline disease risk factor score. We report updated efficacy and safety results for pts in the ECHELON-1 study after a median follow-up of 55.6 months. Methods In this evaluation of longer follow-up, an exploratory analysis of PFS (time from randomization to relapse, progression, or death from any cause) per investigator (INV) was conducted, with a cutoff date of May 18, 2020. Pts with previously untreated Stage III or IV cHL were randomized 1:1 to receive up to six cycles of A+AVD (n=664) or ABVD (n=670) intravenously on days 1 and 15 of a 28-day cycle. An interim PET scan after cycle 2 (PET2) was required. Resolution and improvement (defined as improvement by ≥1 grade from worst grade as of the latest assessment) of peripheral neuropathy (PN) in pts with ongoing symptoms at the end of treatment (EoT) were monitored during the extended follow-up period. The rate of secondary malignancies, and the incidence and outcomes of pregnancies among pts and their partners were also assessed. Results With extended follow-up (median 55.6 months; 95% CI 55.2-56.7) estimated 5-year PFS rates were 82.0% (95% CI 78.7-84.8) for A+AVD and 75.2% (95% CI 71.5-78.4) for ABVD. Overall, PFS per INV favored A+AVD over ABVD (HR 0.691; 95% CI 0.543-0.880; p=0.003) (Table). Exploratory subgroup analyses by PET2 status and age demonstrated PFS benefits regardless of PET2 status (Table); estimated 5-year PFS per INV with A+AVD vs ABVD in the ITT population was 84.7% vs 78.8% in PET2-negative pts (HR 0.676; 95% CI 0.512-0.892; p=0.005), and 60.6% vs 45.9% in PET2-positive pts (HR 0.703; 95% CI 0.393-1.256; p=0.230). PFS benefit with A+AVD over ABVD was also independent of the number of International Prognostic Factors Project (IPFP) risk factors (Figure). After a median follow-up of almost 5-years, 84% (370/442) and 86% (245/286) of pts with treatment-emergent PN reported complete resolution or improvement of symptoms in the A+AVD and ABVD arms, respectively. Median time to complete resolution of PN events that were ongoing at EoT was 30 weeks (range 0-262) in the A+AVD arm and 16 weeks (range 0-267) in the ABVD arm; median time to improvement was 49 weeks (range 8-270) and 12 weeks (range 2-70) , respectively. Of the 132 (30%) pts with ongoing PN in the A+AVD arm, 77 (17%), 39 (9%), 15 (3%) and 1 (<1%) experienced a maximum severity of grade 1, 2, 3 or 4, respectively. In the ABVD arm, PN was ongoing in 61 pts (21%); maximum severity was grade 1, 2, 3 or 4 in 40 (14%), 17 (6%), 4 (1%) and 0 pts, respectively. A total of 124 pregnancies were reported among pts and their partners (40 female and 30 male pts in the A+AVD arm; 26 female and 28 male pts in the ABVD arm). The proportion of live births was similar between arms for female pts (26/40 in the A+AVD arm and 17/26 in the ABVD arm, 65% in each arm) and for male pts' partners (19/30 [63%] in the A+AVD arm and 20/28 [71%] in the ABVD arm). No stillbirths were recorded. Additional follow-up at an estimated median of ~5 years and secondary malignancy data will be presented. Conclusions After a median follow-up of 55.6 months, A+AVD continues to demonstrate a robust and durable treatment benefit independent of disease stage, risk factor score, and PET2 status. In addition, compared with ABVD, treatment adaptation by interim PET2 status is not required and bleomycin exposure is avoided. The sustained PFS benefit with A+AVD is coupled with a manageable safety profile with symptoms of PN improving or resolving over time and similar pregnancy rates in both treatment arms. The benefits observed with A+AVD at this important milestone suggest that A+AVD is an attractive treatment option for all pts with previously untreated Stage III or IV cHL. Disclosures Straus: Karyopharm Therapeutics: Membership on an entity's Board of Directors or advisory committees; Imedex, Inc.: Speakers Bureau; Targeted Oncology: Consultancy, Speakers Bureau; NY Lymphoma Rounds: Consultancy; Takeda Pharmaceuticals: Research Funding, Speakers Bureau; OncLive: Speakers Bureau; Elsevier: Membership on an entity's Board of Directors or advisory committees, Other: CME writer; ASH: Other: Conference in December 2019 on HL to other physicians during ASH; Seattle Genetics: Consultancy, Membership on an entity's Board of Directors or advisory committees. Connors:Seattle Genetics: Other: Sponsorship to educational presentations; Takeda: Other: Sponsorship to educational presentations. Illés:Takeda, Seattle Genetics: Research Funding; Novartis, Janssen, Pfizer, Roche;: Other: Travel, Accommodations, Expenses; Janssen, Celgene, Takeda, Novartis Pharma SAS, Pfizer Pharmaceuticals Israel, Roche;: Consultancy, Honoraria; Celgene, Janssen, Novartis,Roche, Takeda: Consultancy. Lech-Marańda:Roche, Novartis, Takeda, Janssen-Cilag, Amgen, Gilead, AbbVie, Sanofi: Consultancy; Roche, Amgen, Gilead: Speakers Bureau. Feldman:KITE: Honoraria, Speakers Bureau; Abbvie: Honoraria, Speakers Bureau; Morphosis: Other: Ad board; AstraZeneca: Other: Ad board; BMS/Celgene: Consultancy, Honoraria, Speakers Bureau; Seattle Genetics: Consultancy, Speakers Bureau; Janssen: Honoraria, Speakers Bureau; Pharmacyclics: Honoraria, Speakers Bureau; Takeda: Honoraria, Speakers Bureau. Smolewski:Roche Poland: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Sandoz: Honoraria; Morphosis: Honoraria. Savage:Roche (institutional): Research Funding; Merck, BMS, Seattle Genetics, Gilead, AstraZeneca, AbbVie, Servier: Consultancy; BeiGene: Other: Steering Committee; Merck, BMS, Seattle Genetics, Gilead, AstraZeneca, AbbVie: Honoraria. Bartlett:Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pharmacyclics: Research Funding; Seattle Genetics: Consultancy, Research Funding; Roche/Genentech: Consultancy, Research Funding; Seattle Genetics: Membership on an entity's Board of Directors or advisory committees, Research Funding; BTG: Consultancy; Acerta: Consultancy; Affimed Therapeutics: Research Funding; ADC Therapeutics: Consultancy; Autolus: Research Funding; BMS/Celgene: Research Funding; Forty Seven: Research Funding; Immune Design: Research Funding; Janssen: Research Funding; Kite, a Gilead Company: Research Funding; Merck: Research Funding; Millennium: Research Funding. Walewski:Gilead: Consultancy, Honoraria; Servier: Consultancy, Honoraria; BMS: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria; Takeda: Consultancy, Honoraria, Research Funding; Roche: Consultancy, Honoraria, Other: Travel Support, Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; GSK: Research Funding. Ramchandren:Janssen: Research Funding; Pharmacyclics LLC, an AbbVie Company: Consultancy, Research Funding. Zinzani:Eusapharma: Consultancy, Speakers Bureau; Gilead: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Portola: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Immune Design: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Kyowa Kirin: Consultancy, Speakers Bureau; MSD: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Servier: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Immune Design: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; TG Therapeutics, Inc.: Honoraria, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau; EUSA Pharma: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Kirin Kyowa: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; ADC Therapeutics: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Verastem: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celltrion: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen-Cilag: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sandoz: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Merck: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees; Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Hutchings:Celgene, Genmab, Janssen, Novartis, F. Hoffmann-La Roche, Takeda: Research Funding; Genmab, F. Hoffmann-La Roche, Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Munoz:Juno/Celgene/BMS: Consultancy, Research Funding, Speakers Bureau; Alexion: Consultancy; Beigene: Consultancy, Speakers Bureau; Fosunkite: Consultancy; Innovent: Consultancy; Acrotech/Aurobindo: Speakers Bureau; Verastem: Speakers Bureau; AstraZeneca: Speakers Bureau; Kyowa: Consultancy, Honoraria, Speakers Bureau; Janssen: Consultancy, Research Funding, Speakers Bureau; Seattle Genetics: Consultancy, Honoraria, Research Funding, Speakers Bureau; Genentech/Roche: Research Funding, Speakers Bureau; AbbVie: Consultancy, Speakers Bureau; Merck: Research Funding; Portola: Research Funding; Incyte: Research Funding; Millenium: Research Funding; Pfizer: Consultancy; Kite, a Gilead Company: Consultancy, Research Funding, Speakers Bureau; Pharmacyclics: Consultancy, Research Funding, Speakers Bureau; Bayer: Consultancy, Research Funding, Speakers Bureau. Kim:JJ: Research Funding; Celltrion: Research Funding; Kyowa Kirn: Research Funding; Donga: Research Funding; Mundipharma: Research Funding; Pfizer: Research Funding; F. Hoffmann-La Roche: Research Funding. Advani:Astra Zeneca, Bayer Healthcare Pharmaceuticals, Cell Medica, Celgene, Genentech/Roche, Gilead, KitePharma, Kyowa, Portola Pharmaceuticals, Sanofi, Seattle Genetics, Takeda: Consultancy; Celgene, Forty Seven, Inc., Genentech/Roche, Janssen Pharmaceutical, Kura, Merck, Millenium, Pharmacyclics, Regeneron, Seattle Genetics: Research Funding. Ansell:Bristol Myers Squibb: Research Funding; Takeda: Research Funding; ADC Therapeutics: Research Funding; AI Therapeutics: Research Funding; Trillium: Research Funding; Affimed: Research Funding; Regeneron: Research Funding; Seattle Genetics: Research Funding. Younes:HCM: Consultancy; Daiichi Sankyo: Consultancy; Curis: Consultancy; BMS: Consultancy; Novartis: Consultancy; Epizyme: Consultancy; BioPath: Consultancy; AstraZeneca: Current Employment; Janssen: Consultancy; Takeda: Consultancy. Gallamini:Takeda: Other: Speaker. Liu:Takeda Pharmaceuticals: Current Employment. Little:Takeda: Current Employment, Current equity holder in publicly-traded company. Fenton:Seattle Genetics: Current Employment, Current equity holder in publicly-traded company. Fanale:Seattle Genetics: Current Employment, Current equity holder in publicly-traded company. Radford:GlaxoSmithKline: Current equity holder in publicly-traded company, Other: Spouse; AstraZeneca: Current equity holder in publicly-traded company, Other: Spouse; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Pfizer: Research Funding; ADCT: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Consultancy, Honoraria, Speakers Bureau; Novartis: Consultancy, Honoraria; Seattle Genetics: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.

Introduction: Novel approaches to treating patients (pts) with relapsed or refractory (R/R) classical Hodgkin lymphoma (cHL) have improved outcomes but some pts do not respond or, despite initial response, develop progressive disease and have limited treatment options. Camidanlumab tesirine (ADCT-301; Cami) is an antibody-drug conjugate composed of a human IgG1 anti-CD25 monoclonal antibody stochastically conjugated to a potent pyrrolobenzodiazepine (PBD) dimer warhead, which triggers cell death via formation of highly cytotoxic interstrand cross-links. Data from a Phase (Ph) 1 dose-escalation, dose-expansion trial demonstrated an overall response rate (ORR) in pts with cHL of 86.5% (48.6% complete response [CR] rate) at the 45 μg/kg dose. Cami had a generally acceptable safety profile at Ph 1 but there were 5/77 cases (6.5%) of Guillain-Barré syndrome (GBS)/polyradiculopathy (Preferred Terms: 4 GBS and 1 radiculopathy) (Collins et al, ICML June 18-22, 2019, Lugano, Switzerland, Abstract 055). Here, we present preliminary efficacy and safety results of a Ph 2 trial of single-agent Cami in pts with R/R cHL (NCT04052997). Methods: A single-arm, multi-center, open-label, Ph 2 trial is currently enrolling pts ≥16 yrs (US) and ≥18 yrs (outside US) with R/R cHL following ≥3 prior treatment lines (or ≥2 lines in pts ineligible for hematopoietic stem cell transplantation). Eligible pts had prior treatment with brentuximab vedotin and PD-1 blockade, measurable disease per 2014 Lugano Classification, and Eastern Cooperative Oncology Group performance status 0-2. The primary objective is to evaluate efficacy of single-agent Cami by ORR as determined by central review. Secondary objectives include further characterization of additional efficacy endpoints and safety. Pts receive 30-min IV infusions of Cami on Day 1 of each 3-week cycle at a dose of 45 μg/kg for 2 cycles, followed by 30 μg/kg for subsequent cycles for up to 1 yr or until discontinuation due to disease progression, unacceptable toxicity, or other reasons. Pts deriving clinical benefit at 1 yr may be able to continue treatment on a case-by-case basis. Treatment-emergent adverse events (TEAEs) were defined as AEs occurring/worsening from time of first dose to either 30 days post last dose or to start of new anticancer therapy/procedure, whichever occurs first. This analysis was conducted after meeting a protocol-specified criterion for pausing enrollment (≥2 cases of GBS or other relevant severe neurologic toxicity). Results: As of June 15, 2020, 47 pts with R/R cHL were enrolled and are included in this analysis. Median age was 36 (range 23-74) yrs and pts had received a median of 7 (range 3-20) lines of prior therapy, including transplant (Table 1). Pts received a median of 5 (range 2-10; mean 4.9 [SD 1.86]) cycles of Cami. ORR was 80.9% (38/47 pts), with 18 (38.3%) and 20 (42.6%) pts attaining CR and partial response, respectively; 6 pts (12.8%) had stable disease (Figure 1). TEAEs were experienced by all 47 pts; the most common (≥20% of pts) were fatigue (22, 46.8%); nausea, pyrexia, and maculopapular rash (18, 38.3% each); anemia and headache (12, 25.5% each); pruritus (11, 23.4%); arthralgia, constipation, diarrhea, hypophosphatemia, and rash (10, 21.3% each). TEAEs thought to be PBD-associated included skin reactions and nail disorders (36, 76.6%), liver function test abnormalities (14, 29.8%), and edema or effusion (7, 14.9%). There were 3 (6.4%) pts with GBS/polyradiculopathy (Preferred Terms: grade 4 subacute inflammatory demyelinating polyneuropathy, grade 2 radiculopathy, and grade 2 peripheral motor and sensory neuropathy updated to GBS after data cut-off date). In total, 27 (57.4%) pts had grade ≥3 TEAEs; the most common (≥5% of pts) were hypophosphatemia (6, 12.8%) and gamma-glutamyltransferase increased (3, 6.4%). Overall, 3 (6.4%) pts had TEAEs leading to dose reduction/delay and 6 (12.8%) pts had TEAEs leading to treatment discontinuation. Conclusions: Current data show that therapy with Cami has encouraging anti-tumor activity in heavily pretreated pts with R/R cHL. Safety was consistent with that reported at Ph 1, with no new safety concerns identified and similar incidence of GBS/polyradiculopathy. Following a positive risk-benefit assessment, the enrollment pause was lifted, and pts continue to be enrolled. Updated efficacy and safety results will be presented at the meeting. Funding: Study funded by ADC Therapeutics SA. Disclosures Herrera: Pharmacyclics: Research Funding; Bristol Myers Squibb: Consultancy, Other: Travel, Accomodations, Expenses, Research Funding; Merck: Consultancy, Research Funding; Gilead Sciences: Consultancy, Research Funding; Genentech, Inc./F. Hoffmann-La Roche Ltd: Consultancy, Research Funding; Seattle Genetics: Consultancy, Research Funding; Karyopharm: Consultancy; AstraZeneca: Research Funding; Immune Design: Research Funding. Carlo-Stella:Bristol-Myers Squibb, Merck Sharp & Dohme, Janssen Oncology, AstraZeneca: Honoraria; ADC Therapeutics and Rhizen Pharmaceuticals: Research Funding; Boehringer Ingelheim and Sanofi: Consultancy; Servier, Novartis, Genenta Science srl, ADC Therapeutics, F. Hoffmann-La Roche, Karyopharm, Jazz Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees. Collins:Taekda: Consultancy, Honoraria, Other: travel, accommodations, expenses, Speakers Bureau; Novartis: Consultancy, Honoraria, Speakers Bureau; Pfizer: Honoraria; Gilead: Consultancy, Honoraria, Speakers Bureau; ADC Therapeutics: Consultancy, Honoraria; BMS: Consultancy, Honoraria, Research Funding, Speakers Bureau; MSD: Consultancy, Honoraria, Research Funding; Celleron: Consultancy, Honoraria, Research Funding; Celgene: Research Funding; Amgen: Research Funding; BeiGene: Consultancy; Roche: Consultancy, Honoraria, Other: travel, accommodations, expenses , Speakers Bureau. Maddocks:Morphosys: Consultancy, Honoraria; BMS: Consultancy, Research Funding; Karyopharm: Consultancy; Seattle Genetics: Consultancy, Honoraria; ADC Therapeutics, AstraZeneca: Consultancy; Pharmacyclics: Consultancy, Honoraria; Celgene: Consultancy, Honoraria. Bartlett:Autolus: Research Funding; BMS/Celgene: Research Funding; Forty Seven: Research Funding; Immune Design: Research Funding; Seattle Genetics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Research Funding; Kite, a Gilead Company: Research Funding; Merck: Research Funding; Millennium: Research Funding; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pharmacyclics: Research Funding; Seattle Genetics: Consultancy, Research Funding; Roche/Genentech: Consultancy, Research Funding; ADC Therapeutics: Consultancy; BTG: Consultancy; Acerta: Consultancy; Affimed Therapeutics: Research Funding. Savage:BeiGene: Other: Steering Committee; Roche (institutional): Research Funding; Merck, BMS, Seattle Genetics, Gilead, AstraZeneca, AbbVie: Honoraria; Merck, BMS, Seattle Genetics, Gilead, AstraZeneca, AbbVie, Servier: Consultancy. Caimi:ADCT, Kite Therapeutics, Genentech, Amgen, Verastem, TG Therapeutics, Bayer: Consultancy; ADC Therapeutics: Membership on an entity's Board of Directors or advisory committees; Genentech, ADC Therapeutics: Research Funding; Celgene: Speakers Bureau. Hess:ADC Therapeutics: Consultancy, Membership on an entity's Board of Directors or advisory committees; BMS, AstraZeneca: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Zinzani:ADC Therapeutics: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees; Sandoz: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; EUSA Pharma: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celltrion: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Verastem: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen-Cilag: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Kirin Kyowa: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Merck: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Portola: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau; Servier: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; TG Therapeutics, Inc.: Honoraria, Speakers Bureau; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; MSD: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Eusapharma: Consultancy, Speakers Bureau; Kyowa Kirin: Consultancy, Speakers Bureau; Immune Design: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Immune Design: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Cruz:ADC Therapeutics SA: Current Employment, Current equity holder in publicly-traded company. Wang:ADC Therapeutics America, inc: Current Employment, Current equity holder in publicly-traded company. Feingold:ADC Therapeutics: Current Employment, Current equity holder in publicly-traded company. Wuerthner:ADC Therapeutics SA: Current Employment, Current equity holder in publicly-traded company. Ansell:Takeda: Research Funding; Bristol Myers Squibb: Research Funding; Seattle Genetics: Research Funding; Regeneron: Research Funding; Trillium: Research Funding; ADC Therapeutics: Research Funding; Affimed: Research Funding; AI Therapeutics: Research Funding.

Background: While HL is a highly curable cancer, patients (pts) with advanced stage disease experience increased risk of relapse. Delineation of prognosis is desired to compare cohorts and outcomes between trials, and to define groups of pts for whom reduction in treatment may be appropriate or where novel therapeutic approaches are needed. The International Prognostic Score (IPS), which was derived from a discovery set of 1,618 HL pts with complete data, was a seminal publication in the field (Hasenclever and Diehl NEJM 1998). However, these data were published >20 years ago with a significant minority of pts having received chemotherapy regimens no longer in clinical use. More contemporary analyses have shown altered utility of the IPS (e.g., Moccia JCO 2012; Diefenbach BJH 2015). In addition, prior studies identified bulk disease as an adverse prognostic factor in advanced stage HL (Laskar JCO 2004; Johnson JCO 2010). Our objective was to leverage individual pt data (IPD) from HoLISTIC (www.hodgkinconsortium.com) to discover a new, robust, and modern prognostication index for advanced-stage HL pts applicable to diverse settings across the world. Methods: We created a data repository of IPD from clinical trials for newly diagnosed HL pts, which includes 4,085 advanced-stage (III or IV) pts treated in 8 large, prospective studies completed in the modern era (ie, IIL HD9601: Gobbi JCO 2005; Italian HD2000: Federico JCO 2009; ECOG 2496: Gordon JCO 2013; SWOG 0816: Press JCO 2016; IIL HD0801: Zinzani JCO 2016; RATHL: Johnson NEJM 2016; GITIL HD0607: Gallamini JCO 2017; and COG AHOD 0831: Kelly BJH 2019) as well as prominent cancer registries (eg, the Mayo/Iowa Molecular Epidemiologic Resource (MER)). The discovery analysis herein included pts from the ECOG 2496, HD0801 IIL, GITIL HD0607, and SWOG 0816 studies. Furthermore, it was restricted to pts (n=1,279) on these trials with complete data for all 9 covariates of interest: age; sex; advanced stage (III vs IV); B symptoms; any bulk; and values of hemoglobin, white blood count (WBC), lymphocyte count, and albumin. Using Cox proportional hazard (PH) models, we evaluated univariate associations between 5-year progression-free survival (PFS) and overall survival (OS) with the aforementioned prognostic variables. Age was categorized based on plots and optimum model fit (c statistic). Lab values were dichotomized using cut-points from the 1998 IPS. Per convention, treatment factors were not included in the model. To identify independent prognostic factors of PFS and OS, a parsimonious Cox PH model was fit using backward selection of all potential risk factors (P<0.05). Hazard ratios (HR) with 95% confidence interval (CI) were reported. Kaplan Meier (KM) plots were also reported for risk factors in the multivariable (MVA) models to visualize differences. Results: Among all pts, characteristics included: median age of 32.9 years (IQR 25.4-44, range 15-83); 55% male; 49% stage IV; 63% B symptoms; 26% bulk >10 cm; 20% hemoglobin <10.5 g/dL; 15% WBC count ≥15,000/mm3; 9% lymphocyte count <600/mm3; and 63% with albumin <4g/dL. For analysis of age, we observed a U-shaped relationship with PFS (Fig A), which helped delineate optimal cut points of 15-24 years (23.1%), 25-49 years (61.4%), and ≥50 years (15.6%). In univariate analysis: age, stage, B symptoms, bulk, anemia, low lymphocyte count, and low albumin were associated with worse survival. In the MVA model, age >50 years, stage IV disease, B symptoms, and bulky disease were associated with worse PFS; and age >50 years, stage IV disease, bulky disease, anemia, and low albumin were associated with worse OS (Fig B). KM plots for age, stage, and bulk are presented in Fig C. Conclusions. In this international, multi-study analysis of advanced stage HL in the modern era, we identified several factors that were associated with both worse PFS and OS on MVA (ie, age, stage IV disease, and bulky disease). The finding of bulky disease as a significant prognostic factor warrants further investigation. In addition, we detected an age-related U-shaped impact on PFS with inferior outcomes for pts ages 15-25 years and ≥50 years, the latter in an increasing linear fashion. Altogether, these data will serve as a training cohort for a modern HL prognostication index that will be augmented and analyzed with a large independent validation cohort (vis-à-vis the remaining HL data in the HoLISTIC consortium), which will be presented at the ASH meeting. Disclosures Parsons: Seattle Genetics: Consultancy. Advani:Astra Zeneca, Bayer Healthcare Pharmaceuticals, Cell Medica, Celgene, Genentech/Roche, Gilead, KitePharma, Kyowa, Portola Pharmaceuticals, Sanofi, Seattle Genetics, Takeda: Consultancy; Celgene, Forty Seven, Inc., Genentech/Roche, Janssen Pharmaceutical, Kura, Merck, Millenium, Pharmacyclics, Regeneron, Seattle Genetics: Research Funding. Federico:Spectrum: Consultancy, Membership on an entity's Board of Directors or advisory committees; Sandoz: Consultancy, Membership on an entity's Board of Directors or advisory committees; Mundipharma s.r.l.: Research Funding; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees; Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Millennium/Takeda: Research Funding; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Cephalon/Teva: Research Funding. Friedberg:Acerta Pharma - A member of the AstraZeneca Group, Bayer HealthCare Pharmaceuticals.: Other; Bayer: Consultancy; Kite Pharmaceuticals: Research Funding; Portola Pharmaceuticals: Consultancy; Roche: Other: Travel expenses; Seattle Genetics: Research Funding; Astellas: Consultancy. Hutchings:Genmab: Research Funding; Janssen: Research Funding; Roche: Consultancy; Genmab: Consultancy; Takeda: Consultancy; Roche: Research Funding; Celgene: Research Funding; Daiichi: Research Funding; Sankyo: Research Funding; Novartis: Research Funding; Sanofi: Research Funding; Takeda: Research Funding; Roche: Honoraria; Genmab: Honoraria; Takeda: Honoraria. Johnson:MorphoSys: Honoraria; Kymera: Honoraria; Kite Pharma: Honoraria; Incyte: Honoraria; Celgene: Honoraria; Epizyme: Consultancy, Research Funding; Novartis: Honoraria; Takeda: Honoraria; Oncimmune: Consultancy; Boehringer Ingelheim: Consultancy; Janssen: Consultancy; Oncimmune: Consultancy; Janssen: Consultancy; Genmab: Honoraria; Bristol-Myers: Honoraria; Epizyme: Consultancy, Research Funding. Radford:Novartis: Consultancy, Honoraria; BMS: Consultancy, Honoraria, Speakers Bureau; ADCT: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Research Funding; Seattle Genetics: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; GlaxoSmithKline: Current equity holder in publicly-traded company, Other: Spouse; AstraZeneca: Current equity holder in publicly-traded company, Other: Spouse; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Zinzani:MSD: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau; Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees; EUSA Pharma: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sandoz: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Immune Design: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Eusapharma: Consultancy, Speakers Bureau; Verastem: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Kyowa Kirin: Consultancy, Speakers Bureau; TG Therapeutics, Inc.: Honoraria, Speakers Bureau; Kirin Kyowa: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Servier: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen-Cilag: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celltrion: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; ADC Therapeutics: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Portola: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Immune Design: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Merck: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Cerhan:NanoString: Research Funding; BMS/Celgene: Research Funding. Evens:Abbvie: Consultancy, Honoraria; Seattle Genetics: Consultancy, Honoraria, Research Funding; MorphoSys: Consultancy, Honoraria; Research To Practice: Honoraria, Speakers Bureau; Novartis: Consultancy, Honoraria; Epizyme: Consultancy, Honoraria, Research Funding; Merck: Consultancy, Honoraria, Research Funding; Pharmacyclics: Consultancy, Honoraria; Mylteni: Consultancy, Honoraria.

AbstractIdiopathic multicentric Castleman disease (iMCD) is a rare immunologic disorder characterized by systemic inflammation, multicentric lymphadenopathy, and organ dysfunction. Enlarged lymph nodes demonstrate a spectrum of characteristic but variable histopathologic features historically categorized into hyaline vascular (HV) (or hypervascular [HyperV] more recently), plasmacytic, or “mixed.” Though the etiology is unknown, a pro‐inflammatory cytokine storm, often involving interleukin‐6 (IL‐6), contributes to pathogenesis. Anti‐IL‐6 therapy with siltuximab is the only FDA‐ or EMA‐approved treatment based on efficacy and safety in multiple studies. Importantly, no patients considered to have HV histopathology achieved the primary endpoint in the Phase II study. NCCN currently recommends siltuximab first‐line for iMCD, except for patients considered to have HV histopathology. We investigated whether histopathologic subtype should guide siltuximab treatment decisions. Secondary analyses of clinical trial and real‐world data revealed similar clinical benefit across histopathologic subtypes. Notably, only 18 of 79 patients in the Phase II study were consistently classified into histopathologic subtype by three independent review panels, demonstrating limited reliability to guide treatment decisions. Real‐world data further demonstrate siltuximab's effectiveness in patients considered to have HV (or HyperV). Though histopathology is a critical component for diagnosis, there is insufficient evidence to guide treatment based solely on lymph node histopathologic subtype.

Abstract Our group has demonstrated that combinations of epigenetic modifiers produce potent synergy in pre-clinical models of PTCL, and has confirmed this data in early phase clinical studies. We showed that the combination of romidepsin and hypomethylating agents, decitabine or azacytidine, uniquely induces the expression of genes, including cancer testis antigens, gamma interferon and endogenous retrovirus. We are conducting a phase 1 study of pembrolizumab combined with pralatrexate alone (Arm A), with pralatrexate + decitabine (Arm B), or decitabine alone (Arm C) in patients with peripheral T-cell lymphoma (PTCL) and cutaneous T-cell lymphoma. In addition, we are conducting a Phase 1/2A study of durvalumab combined with oral 5-azacitidine + romidepsin (Arm A), pralatrexate + romidepsin (Arm B), romidepsin (Arm C), or oral 5-azacitidine (Arm D) in patients with PTCL. Patient characteristics are listed in Table 1. We have treated a total of 12 patients across the 2 trials and 4 different Arms including pralatrexate plus pembrolizumab (3 patients), pralatrexate, decitabine and pembrolizumab (3 patients), decitabine and pembrolizumab (3 patients) and azacytidine, romidepsin and durvalumab (3 patients). Twelve patients out of 12 received at least one dose of drug and were evaluable for toxicity. There was a dose limiting toxicity (DLT) for each arm including prolonged grade 3 thrombocytopenia, febrile neutropenia, grade 3 hyponatremia and rash, and cytokine release syndrome, respectively. There were no treatment-related deaths. Eight patients out of 12 are evaluable for response at the time of this analysis. Three out of 8 patients achieved a complete remission, 3 out of 8 patients had a partial remission, and 2 out of 8 patients experienced progression of disease. Interestingly, all of the responses were seen in the triple combination of pralatrexate, decitabine, pembrolizumab and azacytidine, romidepsin and durvalumab. These preliminary clinical data suggest that the addition of immune-checkpoint inhibitors on an epigenetic backbone is safe and demonstrates encouraging responses in patient with PTCL and CTCL. These trials are registered at www.clinicaltrials.gov (NCT03240211, NCT03161223). Patient characteristics (n=12)Median age (range)68 (26-77)Sex, n (%) Male Female6 (50) 6 (50)Race, n (%)White/Non-Hispanic White/Hispanic Black Asian Unknown5 (42) 1 (8) 3 (25) 1 (8) 2 (17)Histology, n (%) PTCL, NOS AITL Mycosis Fungoides PTCL, NOS TFH ATLL Sezary Syndrome ALCL, ALK+2 (17) 2 (17) 2 (17) 1 (8) 1 (8) 1 (8) 1 (8)Stage at diagnosis IB II III IV Unknown1 (8) 2 (17) 3 (25) 4 (33) 2 (17)Median number of prior therapies (range) **2 unknown3 (0-5) Citation Format: Enrica Marchi, Helen Ma, Francesca Montanari, Ahmed Sawas, Jennifer K. Lue, Changchun Deng, Kareema T. Whitfield, Sandra Klein, Matthew V. Matthew, Freedy J. Loffredo, Luigi Scotto, Hyejung Lee, Hye A. Kim, Alice T. Jacobs, Aishling M. Rada, Karen A. Khan, Salvia Salvia, John Lister, Nora N. Benanni, Mark A. Francescone, Pier Luigi Zinzani, Wonseog Kim, Owen A. O'Connor. The integration of PD1 blockade with epigenetic therapy is highly active and safe in heavily treated patients with T-cell lymphoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr CT160.