Leis, José F.

Abstract Abstract 1954 Introduction: Vitamin D (VD) deficiency can cause osteomalacia, aching bone pain, muscle weakness, fatigue, increase risk of fracture and precipitate or exacerbate osteopenia/osteoporosis. Allogeneic hematopoietic stem cell transplant (HCT) patients are susceptible to low VD level secondary to poor oral intake, decreased exposure to sunlight and treatment related malabsorption. VD level has been correlated to cancer incidence and VD metabolites have been used in the treatment of myeloid leukemia. VD shows promising immunomodulatory properties and correction of low VD level may mitigate manifestations of graft versus host disease (GVHD). Reports have suggested that low VD level appears to increase the incidence of GVHD. We hypothesize that there is a relationship between low VD level and morbidity (specifically incidence of acute GVHD), mortality and relapse incidence after HCT. We therefore studied VD levels pre- and post-HCT to determine if VD level impacts these outcomes. Patients and Methods: 241 patients underwent myeloblative or non-myeloablative HCT between January 1, 2009 and January 31, 2011 at our institution. Baseline demographic data, disease characteristics, transplant variables and outcomes data were obtained from the transplant database. These data were supplemented by retrospective chart review for pre- and post-transplant VD level. Categories for VD level included normal (>30 ng/ml) or abnormal (<30 ng/ml). Results: 131 (54%) of patients who underwent myeloblative or non-myeloablative HCT had their VD level evaluated either pre-transplant, post-transplant or both. Pre-HCT 57 (56%) patients, 100 days post-HCT 55 (59%) patients and 365 days post-HCT 12 (32%) patients had a low VD level. 51 (38%) of patients had a reduced intensity HCT and 80 patients (62%) had an ablative conditioning regimen. 11 (8.4%) patients had acute GVHD. Comparison of VD level among those with acute GVHD did show a higher incidence of acute GVHD between those with a low or normal VD level (HR=3.14, 95% CI: 0.35–28.33) however this association was not statistically significant (p=0.3079). Survival analysis in those with a low VD level pre-HCT showed there was not a higher risk of mortality (HR=1.14, 95% CI: 0.18–7.38) after adjusting for post- VD level, and this association was not statistically significant (p=0.8921). Survival analysis in those with a low VD level post-HCT did show a higher risk of mortality (HR=2.59, 95% CI: 0.26–25) after adjusting for pre-HCT VD level, however, this association was not statistically significant (p=0.4155). The relationship between VD level and relapse at 1 year post-HCT was not able to be examined because the VD level for patients who relapsed was not available. Conclusions: Half of patients undergoing HCT had VD testing pre- or post- HCT. Just over half of the patients tested had a low VD level pre- and 100 days post-HCT. It is notable that 365 days post HCT the number of patients with low VD level had decreased. This could be attributable to less time in the hospital thus increasing sun exposure, increasing performance status allowing better ingestion and absorption of VD in the gastrointestinal tract or proper supplementation of a low level noted previously. There was no significant difference in incidence of acute GVHD by VD level though there was a trend for increased risk. Pre- and post-HCT VD level did not significantly impact mortality but there was a trend toward higher risk in those with a low VD level post-HCT. This is the first study, to our knowledge, to evaluate the impact of VD level on mortality post-HCT. Our study confirms that many patients have a low VD level pre-and post-HCT. These findings, especially the trend towards a higher mortality risk and higher incidence of acute GVHD in those who have a low VD level post-HCT, warrant further prospective investigation. VD supplementation may be a low cost, easy to implement addition to routine post HCT care that might reduce HCT associated mortality. Disclosures: Reeder: Celgene: Research Funding.

Abstract Abstract 1379 Background: Although chemoimmunotherapy (CIT) has substantially improved response rates, treatment free survival, and overall survival in patients with chronic lymphocytic leukemia (CLL), only 40–50% of patients achieve a complete remission and the majority have residual disease when evaluated using sensitive assays for minimal residual disease (MRD). While this observation created interest in consolidation therapy, previous alemtuzumab based consolidation trials have demonstrated excess morbidity/mortality. We conducted a lenalidomide based consolidation trial for patients with previously untreated CLL who received 6 cycles of induction with pentostatin, cyclophosphamide and rituximab (PCR). Methods: Eligible patients were previously untreated and had CLL in need of treatment according to the NCI-WG criteria (Blood 111:5446). Treatment schema consisted of 6 cycles of pentostatin (2 mg/m2), cyclophosphamide (600 mg/m2) and rituximab (375 mg/m2) given every 21 days (Blood 109:405). All patients completing 6 cycles of PCR, underwent complete restaging and evaluation for MRD using sensitive flow cytometry (Leukemia 21:956). Following restaging and adequate recovery of blood counts, patients received 6 mos of lenalidomide consolidation by continuous daily administration. The starting lenalidomide dose was 5 mg/day with escalation to 10 mg/day after the first cycle as tolerated. Patients again underwent complete restaging and MRD evaluation after 6 mos of lenalidomide. At the time of this restaging, MRD negative patients entered observation. Those with residual disease continued on lenalidomide and underwent repeat MRD assessment every 3 mos with cessation of lenalidomide when an MRD negative state achieved. Results: 45 patients were enrolled at Mayo Clinic between 3/2008 and 11/2009. 44 patients were eligible for treatment: 71% male, median age 65 (range: 44–78); intermediate Rai risk 61%; high Rai risk 39%. On prognostic testing 32% were CD38+, 52% Zap-70 +, 52% IGHV unmutated, and 16% had high risk FISH (del 17p13; del 11q22). 38 of 44 eligible patients (86%) completed 6 cycles of PCR induction. Adverse events deemed at least possibly related to PCR induction included 19 (43%) patients with grade 3+ hematologic toxicity and 9 (20%) with grade 3+ non-hematologic toxicity. The Overall response rate to induction was 98% with 15 CR/CRi, 3 CCR, 9 nPR, and 16 PR. Four patients with CR were also MRD negative at the completion of induction. Of 38 patients who completed induction, 34 initiated lenalidomide consolidation. Thus, by protocol intent to treat analysis, 34/44 (77%) patients starting CIT with PCR were able to receive consolidation therapy. The remaining patients were unable to initiate consolidation due to: failure to complete induction (6 patients), disease progression (1), adverse event (1) and patient refusal (2). Among the 34 patients who initiated consolidation, the median number of cycles of lenalidomide received was 5.5 (range: 1–19). Adverse events deemed at least possibly related to lenalidomide consolidation included 22 (65%) patients with grade 3+ hematologic toxicity and 4 (12%) with grade 3+ non-hematologic toxicity. Among the 34 patients who received at least 1 cycle of lenalidomide, 4 patients have improved the quality of their response to date with 11 patients still on lenalidomide at the time of this report. After median follow-up of 16 mos, 42/44 patients are alive and median duration of response has not been reached. To date 3/44 (7%) of patients have progressed to require additional treatment. Finally, since eligibility was nearly identical to our historic trial of PCR without lenalidomide consolidation, we compared the 44 patients in the present trial to the 64 patients previously treated on our PCR trial (Blood 109:405). Demographic and prognostic characteristics of the patients in the two studies were similar. With the caveat it represents comparison across phase II trials, the proportion of patients free of retreatment at 12 mos was 97% (95%CI: 91–100) for PCR-L vs. 78% (95%CI: 68–89) for PCR (Figure 1). Conclusion: We report here the first results of lenalidomide based consolidation for CLL patients receiving first-line CIT induction. Although lenalidomide consolidation appears to improve the quality of response and prolong time to retreatment, longer follow-up is necessary to determine the clinical benefit of this strategy. Disclosures: Shanafelt: Celgene: Research Funding; Hospira: Research Funding; Genentech: Research Funding. Off Label Use: Lenalidomide. Kay:Celgene: Research Funding; Hospira: Research Funding; Genentech: Research Funding.

Abstract CLL is a clinically heterogeneous disease with wide ranging disease course. A novel CLL-IPI based on Rai/Binet stage, IGHV-mutation status, TP53 mutation/deletion, B2M level, and age was developed to stratify patients into 4 risk groups, with a c-statistic of 0.75. Next-generation sequencing has identified ~60 genes recurrently mutated in CLL, some of which are associated with poor overall survival, whereas the clinical effect of most genes is still unknown. Herein, we examine whether somatic mutations in these putative driver genes are associated with time to first treatment (TTT), and whether they add prognostic value beyond CLL-IPI. Based on the 2008 International Workshop CLL criteria, we identified 100 CLL and 96 high-count monoclonal B-cell lymphocytosis (MBL) newly diagnosed from the Mayo Clinic CLL biobank. Pre-treatment peripheral blood mononuclear cells were collected &lt;2 years of diagnosis and tumor DNA was extracted from sorted CD5+/CD19+. We sequenced the coding regions of 61 recurrently mutated CLL driver genes using a custom SureSelect panel, with 24 samples per flow cell in Illumina HiSeq 4000. The average coverage depth was &gt;1000X. Somatic mutations were called using MuTect2 in tumor-only mode. To remove germline variants, variants were eliminated based on minor allele frequencies &gt;0.01%, identified in 1000 Genomes Project, ExAC and/or ESP6500 databases, unless present in known mutation hotspots or COSMIC. After filtering, high/moderate impact mutations were analyzed using Cox regression, to estimate hazard ratios (HR) and 95% confidence intervals (CI) to test for associations with TTT. Among 196 patients the most commonly mutated genes were TP53 (11%), ATM (10%), SF3B1 (10%), NOTCH1 (9%), CHD2 (8%), and BIRC3 (7%). The median follow-up was 8.7 years, and 73 patients were subsequently treated. ATM (HR=3.27, CI:1.8-6.1, P=0.0002) and NOTCH1 (HR=2.41, CI:1.3-4.6, P=0.008) were associated with TTT. When evaluating the total number of mutated genes, we found 32%, 29%, and 39% patients had ≥2, 1, or 0 genes mutated, respectively, and this was associated with shorter TTT (HR=1.74, CI:1.3-2.4, P=0.0005) adjusting for sex and CLL-IPI with a c-statistic=0.8 (CI: 0.75-0.84). When stratified by CLL-IPI, the association held for low (N=99, HR=1.88, CI:1.1-3.4, P=0.03) and intermediate risk (N=54, HR=1.87, CI:1.1-3.2, P=0.03) but not high/very high risk (N=35, HR=1.07, CI:0.6-1.9, P=0.83). We demonstrated that the total number of CLL putative driver genes with high or moderate impact mutations provided prognostic information in newly diagnosed CLL/MBL beyond CLL-IPI. Moreover, even among those with low or intermediate CLL-IPI risk, the total number of somatic mutations separated those patients who progressed. Sequencing the CLL driver genes at time of diagnosis could be a potential biomarker for outcome prediction. Citation Format: Geffen Kleinstern, Daniel R. O’Brien, Brian F. Kabat, Kari G. Chaffee, Aaron D. Norman, Timothy G. Call, Sameer A. Parikh, Jose F. Leis, Wei Ding, James R. Cerhan, Neil E. Kay, Susan L. Slager, Esteban Braggio. Somatic mutations within chronic lymphocytic leukemia (CLL) putative driver genes are associated with outcomes beyond the CLL international prognostic index (CLL-IPI) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4466.

Background:We have previously reported that ∼50% of CLL patients (pts) experience rapid flare of disease when they discontinue ibrutinib therapy due to progression of disease (CLL or Richter's transformation [RT]) (Hampel et al, JCO suppl, 2018). This lead to the clinical practice of overlapping venetoclax with ibrutinib for combination therapy in this setting to prevent ibrutinib withdrawal.Aims:To evaluate the role of continuing ibrutinib beyond the start of salvage venetoclax in pts who have progression of disease on ibrutinib monotherapy, both in preventing ibrutinib withdrawal associated with ibrutinib discontinuation and in disease response.Methods:We identified all CLL pts at Mayo Clinic (3/2017–11/2018) who had disease progression on ibrutinib therapy, where venetoclax was added as subsequent treatment while ibrutinib was continued. CLL‐specific characteristics, treatment timeline and toxicities, and disease course following combination therapy were ascertained. All pts started venetoclax according to the weekly ramp‐up per the package instructions.Results:Eighteen pts treated with the addition of venetoclax to ibrutinib therapy were identified; indications were CLL progression (n = 13) and RT (n = 5). BTK or PLCG2 mutations were present in 8/13 pts. Median duration of follow‐up was 9.6 months after the start of combination therapy.The target venetoclax dose was reached by 5 weeks in 13 pts; reasons for delaying or stopping dose escalation included diarrhea (n = 2), sepsis (n = 2), and neutropenia (n = 1). No patient experienced a disease flare during venetoclax ramp‐up.The median duration of combination ibrutinib and venetoclax therapy was 3 months (range, 0–14 months). Of 18 pts who started combination therapy with ibrutinib and venetoclax, ibrutinib was discontinued in 10 pts. Reasons included hematopoietic stem cell transplant (n = 2), planned stop after adequate disease control (n = 4), financial reasons (n = 1), toxicity (neutropenia n = 1, immune thrombocytopenia/bleeding risk n = 1), and death (n = 1). Only 1 patient experienced ibrutinib withdrawal, which occurred following planned discontinuation after clinical complete response (CR) with a 41 day overlap and toleration of venetoclax 400 mg daily; management with re‐initiation of ibrutinib was effective in regaining disease control. Of 9 pts who stopped ibrutinib, 4 pts had a slow taper over 2–8 weeks, and 2 pts also received corticosteroids at the time of ibrutinib discontinuation.Among the other 8 pts who did not discontinue ibrutinib, 6 pts remain on the combination with venetoclax (median duration 6.5 months, range 3–14 months), and 2 pts continued on ibrutinib following venetoclax discontinuation due to disease progression (both pts received further combination of ibrutinib with multi‐agent chemotherapy).The overall response rate (ORR) to combination therapy with ibrutinib and venetoclax was 81% (CR/clinical CR n = 9, partial response n = 4, stable disease n = 1, and primary refractory disease n = 2). The duration of combination therapy was <4 weeks in 2 pts, precluding response assessment. The estimated 12‐month event‐free survival was 54% (95% CI 33–87%), and the estimated 12‐month overall survival from start of combination therapy was 79% (95% CI 60–100%); see Figure 1.Summary/Conclusion:Among CLL pts who develop progression of disease on ibrutinib monotherapy, continued ibrutinib therapy with addition of venetoclax was feasible, ameliorated ibrutinib withdrawal, and was associated with high ORR.image

The prevalence, clinicopathologic correlates, and outcomes of previously untreated chronic lymphocytic leukemia (CLL) patients with IGH‐BCL2 and IGH‐BCL3 translocations are not well known. Using the Mayo Clinic CLL database, we identified patients seen between March 1, 2002 and September 30, 2016 who had FISH testing performed within 3 years of CLL diagnosis. The prognostic profile, time to first therapy (TTT), and overall survival (OS) of patients with IGH‐BCL2 and IGH‐BCL3 translocation were compared to patients without these abnormalities (non‐IGH group). Of 1684 patients who met the inclusion criteria, 38 (2.2%) had IGH‐BCL2, and 16 (0.9%) had IGH‐BCL3 translocation at diagnosis. Patients with IGH‐BCL3 translocation were more likely to have high and very‐high CLL‐International Prognostic Index, compared to patients with IGH‐BCL2 translocation and the non‐IGH group. The 5‐year probability of requiring therapy was significantly higher for IGH‐BCL3 compared to IGH‐BCL2 and non‐IGH groups (84% vs 33% vs 29%, respectively, P < 0.0001). The 5‐year OS was significantly shorter for IGH‐BCL3 compared to IGH‐BCL2 and non‐IGH groups (45% vs 89% vs 86%, respectively, P < 0.0001). On multivariable analyses, IGH‐BCL3 translocation was associated with a shorter TTT (hazard ratio [HR] = 2.7; P = 0.005) and shorter OS (HR = 5.5; P < 0.0001); IGH‐BCL2 translocation did not impact TTT and OS. In conclusion, approximately 3% of all newly diagnosed CLL patients have either an IGH‐BCL2 or IGH‐BCL3 translocation. Patients with IGH‐BCL3 translocations have a distinct prognostic profile and outcome. These results support the inclusion of an IGH probe during the routine evaluation of FISH abnormalities in newly diagnosed CLL.