ALBERT

Description: Background: The treatment of multiple myeloma (MM) is optimized by use of combination regimens consisting of agents with different mechanisms of action. Panobinostat is a pan-inhibitor of histone deacetylases types I,II, and IV. Panobinostat, bortezomib, dexamethasone was shown to be an effective regimen (San Miguel et al Lancet Hematol 2016; Richardson et al Blood 2016), leading to the FDA approval of panobinostat for patients with relapsed/refractory MM. Carfilzomib is a proteasome inhibitor that was FDA approved in relapsed/refractory MM with the advantage of minimal neuropathy. Panobinostat and carfilzomib has also been shown to be a highly active regimen in relapsed/refractory MM with an overall response rate of up to 75% (Berdeja et al, Haematologica, 2015). With the heterogeneity of MM, individual patients exhibit wide variability in responses to drug combinations. A test that could predict patient responses to specific agents might enable clinicians to optimize therapy for patients, improving outcomes. We developed an in vitro high throughput drug sensitivity assay with formal synergy testing to predict response. In this ongoing trial, Panobinostat with Carfilzomib and Dexamethasone for Relapsed/Refractory Multiple Myeloma: Correlation with In Vitro Chemosensitivity Testing (NCT03256045), we will correlate individual patient in vitro sensitivity assay results with individual clinical response to the same triple drug regimen. Study Design and Methods: This study's objective is to directly demonstrate the utility of a high throughput drug sensitivity assay in determining biomarkers (e.g. individual IC50s, AUCs and/or synergy scores) to accurately predict response to combination therapy that was given prospectively to all enrolled patients. We are enrolling patients with relapsed/refractory MM by IMWG criteria with measurable disease defined by the detection of a quantifiable monoclonal protein in the urine or serum or an abnormal serum free light chain ratio. Additionally, patients must have adequate blood counts and organ function. Patients who have had prior autologous or allogeneic transplants or CAR-T cell therapy are eligible. The regimen consists of panobinostat 20 mg orally on days 1,3,5,15,17,19; carfilzomib 20 mg/m2/dose IV on days 1,2 of cycle 1, then dose escalation up to 45 mg/m2/dose days 8,9,15,16 and all days for subsequent cycles; and dexamethasone 20 mg orally on days of carfilzomib. Dose reductions of all three drugs are permitted per patient tolerance to allow continuation on study treatment. Up to 12 cycles of treatment are permitted. Patients are monitored by serial electrocardiograms and assessments of cardiac function. Safety parameters including adverse events are recorded. CD138+ plasma cells are procured from the patient bone marrow (aspiration and biopsy) and blood (when present) by magnetic bead separation. Cells are then added to 384-well plates and incubated overnight before the drugs are added. Cells are exposed to 8 concentrations (spanning 4 logs) of panobinostat, carfilzomib, or dexamethasone as singlet, doublet and triplet combinations for 72 hours. Cell viability is determined using CellTiter-Glo and IC50 and AUC values are are calculated by fitting data using least squares method to the standard four-parameter logistic model. Curve fitting is performed using IDBS XLFit software. The combination index is calculated by the method described by Chou and Talalay, Trends Pharmacol Sci 1983;4:450-4. Concentrations of Drug1 and Drug2 (that is, panobinostat and dexamethasone or panobinostat and carfilzomib) alone or in combinations are determined that give rise to 90% growth inhibition. At 90% Growth Inhibition, the Combination Index or CI = ([D1] in the combination / [D1] alone) + ([D2] in the combination / [D2] alone). All patients are treated with panobinostat, carfilzomib, and dexamethasone and evaluated for response using the IMWG response criteria. At the completion of enrollment at 35 patients, we plan to correlate the in vitro testing data with in vivo clinical response to determine appropriate biomarkers. This will be done by correlating the IC50s and AUCs for the individual drugs for responders vs. non-responders (including degree of response VGPR vs PR vs SD), as well as correlations of the synergy scores for each of the pairs of drugs in the responders vs. non-responders. Enrollment was initiated in April 2018. Disclosures Becker: Accordant Health Services/Caremark: Consultancy; AbbVie, Amgen, Bristol-Myers Squibb, Glycomimetics, Invivoscribe, JW Pharmaceuticals, Novartis, Trovagene: Research Funding; The France Foundation: Honoraria. Libby:Abbvie: Consultancy; Pharmacyclics and Janssen: Consultancy; Akcea: Consultancy; Alnylam: Consultancy. Cowan:Juno: Research Funding; Abbvie: Research Funding; Sanofi: Consultancy; Janssen: Consultancy, Research Funding; Cellectar: Consultancy; Celgene: Consultancy, Research Funding. Hammer:Glycomimetics: Consultancy.

Description: Abstract 349 Natural killer (NK) cells are vital in the control of viral infection and malignancy, in particular AML. Affinity strength between NK receptors and their HLA ligands control both NK effector function and degree of NK inhibition. Differences in binding affinity between allotypes of the NK receptor KIR3DL1 and allotypes of its ligand HLA-Bw4 depend on the expression levels of the receptor and the amino acid residue at position 80 in the ligand. Because receptor-ligand affinities are associated with differences in HIV control, we hypothesized that different affinities between donor KIR3DL1 and donor-recipient HLA-Bw4 allotypes would impact the risk for AML relapse following allogeneic hematopoietic stem cell transplantation (HCT). Methods: We evaluated 299 AML patients who underwent allogeneic HCT from an unrelated donor between 1995 and 2002. Clinical data, HLA allotyping, and donor DNA were provided by the CIBMTR. KIR3DL1 allotyping was executed using PCR- and sequence-based methods. Donors were segregated into those with high-, low- and null expressing KIR3DL1 allele groups [3DL1-H (n=130), 3DL1-L (n=69), 3DL1-N (n=82)] and HLA-B allele groups (Bw6/Bw6, Bw4-I80, Bw4-T80). 3DL1-N genotypes are predictive of poor surface expression and were analyzed separately. Patients and donors were matched at 9 or 10 HLA loci in all cases, with only 3 donor-patient pairs mismatched for HLA-Bw4 ligands. Affinity cohorts were compared using Cox regression for the time-to-event outcomes of relapse and overall mortality (OM). Kaplan-Meier estimates of overall survival and cumulative incidence estimates of relapse were obtained. Results: Recipients of 3DL1-H and 3DL1-L donors were analyzed for high and low-affinity associations with post-HCT AML relapse. Among patients with a 3DL1-H donor, those transplanted from donors with the low-affinity KIR/HLA allotype combination 3DL1-H/Bw4-T80 had lower risk of relapse when compared to those with the high-affinity 3DL1-H/Bw4-I80 combination (HR 0.22; p=.003, Table) and even moreso when compared to the extra-high affinity combinations of 3DL1-H with Bw4-I80-B*2702 or B*57 (HR 0.10; p

Description: Background: Despite improved treatment options, indolent non-Hodgkin lymphoma (NHL) and Mantle Cell Lymphoma (MCL) remain incurable for most patients. Fenretinide (4-hydroxy(phenyl)retinamide; 4-HPR), an orally bioavailable synthetic retinoid, has been shown to induce apoptotic cell death in a variety of tumor types, presumably via intratumoral induction of oxygen free radicals. Our group has shown single-agent fenretinide anti-B-NHL activity as well as synergy with anti-CD20 antibody therapy when tested in vitro (Shan et al Clin Cancer Res. 2001) and in human xenograft models (Gopal et al, Blood 2004). These preclinical data support the first trial to evaluate this strategy of fenretinide and rituximab in patients with B-cell malignancies. Here we report results from a phase I-II study evaluating the safety and efficacy of fenretinide with rituximab for indolent NHL and MCL. Methods: This was an open-label, phase I/II study conducted at the Fred Hutchinson Cancer Research Center (FHCRC) and Seattle Cancer Care Alliance, Seattle, WA (ClinicalTrials.gov identifier: NCT00288067). The study was approved by the institutional review board at FHCRC and written informed consent was obtained from all patients. Major eligibility criteria included: CD20 positive lymphoid malignancy, radiographically measurable disease, ECOG PS ²2, and adequate organ function. The phase I portion evaluated the safety of dosing single agent fenretinide at 900 mg/m2 PO BID for days 1-5 of a 7 day cycle and allowed de-escalation for excess toxicity. The phase II portion added 375 mg/m2 IV rituximab weekly on weeks 5-9 then every 3 months. All patients could remain on therapy until disease progression or unacceptable toxicity. Response assessment occurred approximately every 3 months. Correlative studies included fenretinide pharmacokinetics, serum retinol concentrations, and evaluation of tumor expression of BCL-2 family proteins. Response was scored by standard criteria (Cheson 1999). Results: Thirty-two patients enrolled in the study: 7 patients in phase I, and 25 patients in phase II. The median age was 64 years (range, 40 - 78), 81% were male, and the median number of prior therapies was 1 (range, 0 - 10) with 22 (69%) having received prior rituximab and 8 (25%) with rituximab-refractory disease. Histologies included 13 CLL/SLL, 10 follicular (FL), 7 mantle cell (MCL), 1 lymphoplasmacytic, and 1 marginal zone. No dose limiting toxicities were observed in the phase I portion, and 900 mg/m2 was the dose level delivered in combination with rituximab for the phase II component. The most common treatment-related adverse events (AE) of any grade were reversible night blindness (n=18, 56%), other eye disorders (n=17, 53%), rash (n=12, 38%), and photosensitivity (n=8, 25%). The most common treatment related AEs of grade 3 or higher included: maculopapular rash, night blindness, and decreased lymphocyte count. Three patients (9%) discontinued treatment early due to toxicity (rash-2, GI toxicity-1). One patient with MCL in the phase I portion experienced stable disease (SD) lasting 35 months. In the phase II portion of the study, 5 (20%) patientÕs disease responded (Figure), with 2 (8%) achieving complete remission (both SLL/CLL), and 3 (12%) achieving partial remission (2 FL, 1 MCL). In addition 16 (64%) patients had SD. The median progression-free survival was 9 months (range, 6 - 31 months), and the median overall survival was not reached (range, 33 months to not reached). Median time to progression of responders was 14.5 months. The one-month median peak and trough concentrations of fenretinide were 11.45 µM and 2.5 µM, respectively. Correlative studies assessing Bcl-2, BAX, and apoptosis in the 13 patients with circulating tumor cells were not able to associate these data with response, or survival. Discussion: In this phase I/II study, the combination of fenretinide and rituximab was well tolerated with predictable, reversible toxicities with up to 4.5 years of continuous therapy. Though the ORR was modest (20%), the majority had of patients had disease control (ORR + SD=84%) which lasted for 〉 6 months. Further study of this novel combination should focus on identifying the subset of B-NHL that is most likely to respond or the rational addition of other agents to augment these anti-tumor effects. Figure 1. Figure 1. Disclosures Pagel: Actinium Pharmacetuicals, Inc.: Equity Ownership. Gopal:Merck: Research Funding; Emergent/Abbott: Research Funding; Cephalon/Teva: Research Funding; BioMarin: Research Funding; Sanofi-Aventis: Honoraria; Millenium: Honoraria, Research Funding; Seattle Genetics: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Spectrum: Consultancy, Research Funding; Gilead: Consultancy, Research Funding; Piramal: Research Funding; Biogen Idec, BMS: Research Funding.

Description: The majority of patients with relapsed or refractory B-cell, non-Hodgkin’s lymphoma (NHL) are over 60 years of age, yet many are denied potentially curative high-dose regimens due to concerns of excessive toxicity with stem cell transplantation in this age group. Myeloablative anti-CD20 radioimmunotherapy (RIT) can deliver curative radiation doses to tumor sites while limiting exposure to normal organs and may be ideal for older adults requiring high-dose therapy. We have treated 24 patients with relapsed or refractory B-cell NHL aged ≥60 years using high-dose I-131-tositumomab (GlaxoSmithKline) and ASCT on a phase II trial. Patients were required to have a performance status of 0–1, acceptable organ function, ≥2x106 CD34+ cells/kg collected, and 1 extranodal site = 21%, elevated LDH at treatment = 46%, IPI score at transplant 3–5 = 46%, Histology: diffuse large B-cell (DLBCL)=9 pts (with 4/9 transformed from follicular lymphoma [FL]), mantle cell (MCL)=8 pts, FL=6 pts, and marginal zone (MZL) 1 pt. The median I-131 activity administered was 525 mCi (range 328–1154 mCi) with dose limiting organs being lung, liver, and kidney in 12, 8, and 4 patients, respectively. The therapy was well tolerated with no treatment-related deaths, and no grade 3–4 Bearman toxicity. NCI CTC non-hematopoeitic toxicities by day 100 included: Grade 4=2/24 and Grade 3=17/24. The median time after ASCT for recovery of platelets 〉 20K and neutrophils 〉500 was 10 and 15 days, respectively. Sixteen of 24 pts remain alive (67%) and 10 (42%) are alive and progression-free with a median follow up from ASCT of 2.2 yrs (range 1 mo.–4.9 yrs.) for survivors. The estimated 3-year overall and progression-free survival are 56% and 37%, respectively. Surviving patients include 6/8 with MCL, 5/7 with FL/MZL, and 5/9 with DLBCL as well as 9/13 with chemoresistant disease. Myeloablative I-131-tositumomab with ASCT is a well-tolerated and effective transplant option for older adults with high-risk, relapsed B-NHL, though longer follow-up and additional pts will be needed to confirm the reproducibility and durability of these findings.

Description: In patients with myelodysplastic syndromes (MDS), apoptosis in hematopoietic cells is up-regulated in low-grade disease, whereas advanced disease is characterized by apoptosis resistance. We have shown that marrow stroma–derived signals convey sensitivity to tumor-necrosis-factor alpha (TNF-α)–mediated apoptosis in otherwise-resistant KG1a myeloid cells and CD34+ cells from MDS marrow. Here, we used a PhosphoScan proteomic liquid chromatography–mass spectrometry method to identify signals relevant for this effect. The transcription factor DJ-1/PARK-7 (DJ-1) was highly phosphorylated in KG1a cells cultured without stroma but dephosphorylated after stroma coculture, whereas expression of p53 increased significantly, suggesting a stroma contact-dependent effect of DJ-1 on p53. In CD34+ marrow cells from advanced MDS, expression of DJ-1 was up-regulated, whereas p53 levels were low, resulting in significantly greater DJ-1/p53 ratios than in patients with low-grade MDS (P = .01). DJ-1 levels were correlated with increasing International Prognostic Scoring System scores (P = .006). Increasing DJ-1/p53 ratios were associated with an increased risk of mortality, although the correlation did not reach statistical significance (P = .18). These data suggest that DJ-1/p53 interactions contribute to apoptosis resistance in clonal myeloid cells and may serve as a prognostic marker in patients with MDS.

Description: Key Points Anti-CD45 RIT may replace TBI and simplify BMT-preparative regimens. Anti-CD45 RIT and haploidentical BMT, without TBI, prolongs survival in a murine leukemia model.

Description: Abstract 3085 The International Working Group (IWG) has determined that prognosis in myelofibrosis is predicted by a scoring system that includes the following parameters: age 〉 65 years, constitutional symptoms, hemoglobin 〈 10 g/dL, leukocyte count 〉 25 × 109/L and circulating peripheral blasts ≥ 1%. Based on these factors patients may be placed into 4 separate categories: low, intermediate-1, intermediate-2 or high risk. The median survivals of these 4 groups are 135, 95, 48 and 27 months, respectively. The IWG scoring system has been validated in a dynamic prognostic model. However, there have been no publications evaluating the use of the IWG prognostic model in patients with myelofibrosis who receive hematopoietic cell transplantation (HCT). We performed a retrospective review of 181 patients with a diagnosis of myelofibrosis who underwent HCT at the Fred Hutchinson Cancer Research Center between March, 1990 and November 2009. Twelve patients received an autologous transplant and 169 patients underwent an allogeneic transplant using an HLA-matched related (78), syngeneic (3), HLA-mismatched related (4), HLA-matched unrelated (66) or HLA-mismatched unrelated (18) donor. The median age at time of HCT was 51 (range: 12–78) years. Among the 169 patients who received allogeneic transplants, conditioning regimens consisted of oral busulfan, 16 mg/kg (136); oral busulfan, 7 mg/kg with TBI 12 Gy (9); TBI 12–13 Gy (4); Melphalan, 140 mg/kg (3); Fludarabine, 90 mg/m2 with TBI 2–4 Gy (16); and Treosulfan, 42 gm/m2 with Fludarabine, 150 mg/m2 (1). GVHD prophylaxis consisted of cyclosporin/methotrexate (99), tacrolimus/methotrexate (49), cyclosporin/mycophenolate (14) or tacrolimus/mycophenolate (4). We were able to obtain the full set of parameters involved in calculating the IWG score in all 181 patients. Historical records pre-transplant and arrival records prior to transplant were reviewed. Patients were assigned to the highest possible IWG score based on age at time of HCT, history of constitutional symptoms, hemoglobin 〈 10 g/dL or transfusion dependence at time of transplant, history of leukocyte counts 〉 25 × 109/L, and history of peripheral blasts ≥ 1%. Based upon these parameters, there were 21 patients with low risk, 48 patients with intermediate-1, 54 patients with intermediate-2, and 58 patients with high risk disease. The IWG score was highly predictive of survival in the post-transplant setting with a hazard ratio (HR) of 4.4 (95% CI 1.6–12.5, p=0.005) for mortality in high risk patients compared to low risk patients. Patients in the low risk category had a significantly lower risk of relapse HR=0 (95% CI 0, p=0.046) in comparison to patients with high risk disease. In addition, patients with high risk disease had a significantly greater risk of transplant related mortality HR=3.7 (95% CI 1.3–11, p=0.016) in comparison to patients with low risk disease. This is the first examination of post-transplant outcomes by the pre-transplant IWG score. This analysis suggests that patient and disease characteristics considered in the IWG score and shown to be of prognostic significance at diagnosis also predict post-transplant survival. These findings, with a follow-up extending to two decades, indicate that while transplantation was curative for a proportion of patients, it could not completely overcome the risk conveyed by pre-transplant risk factors. It is our hope that future studies will use this information to address the optimal timing of appropriate interventions including HCT. Disclosures: No relevant conflicts of interest to declare.