Ding, Wei

Abstract Backgrounds B cell receptor (BCR) signals and microenvironment protection have been recognized to have key influences on CLL survival and activation. Akt activation is down-stream of the BCR signaling cascade and is critical in the mediation of the bi-directional interactions between CLL B-cells and bone marrow stroma. MK2206 is an allosteric Akt inhibitor previously tested for safety in solid tumor patients. Our preclinical data has demonstrated the synergy of MK2206 with bendamustine (B) to induce CLL apoptosis in vitro. MK2206 also abolished the signal activation and cytokine production induced by BCR ligation in CLL leukemic cells (Ding, ASH 2012). Therefore, we conducted a phase 1 trial testing the safety and efficacy of MK2206 in combination with bendamustine and rituximab (BR) for patients with relapsed/refractory CLL. Methods A phase 1 dose-escalation study was designed to define the maximum tolerated dose (MTD) as well as the safety and efficacy of 3 dose levels (90 mg or 135 mg or 200 mg weekly) of the oral Akt inhibitor MK2206 in combination with bendamustine (70 mg/m2 daily for 2 days in each cycle) and rituximab (cycle 1: 375 mg/m2, cycle 2-6: 500 mg/m2) therapy in relapse/refractory CLL patients. To test the targeting efficacy of MK2206 on Akt and downstream signals, we designed a one-week “run-in” of single agent MK2206 before the initiation of BR during cycle 1. MK2206 was then given along with BR on day 1 of cycles 2-6. Tumor response was evaluated 2 months after the 6th/last cycle of therapy based on IWCLL 2008 criteria. Correlative laboratory studies included assessment of Akt signaling and the plasma cytokine levels (multiplex beads assay (Invitrogen)) at baseline and after one week of first dose of single agent MK2206. Results Nine patients (median age 68) were enrolled in the phase I portion of this trial. All 9 patients had unmutated immunoglobulin heavy chain variable region genes (IGHV) and 4 had del(11q). Six had received prior chemoimmunotherapy (CIT: FCR or PCR or PCO) and 5 had high risk disease defined as early progression within 26 months of the last CIT. Three had received alemtuzumab containing regimen. We have observed potent lymphocyte mobilization in all evaluated patients (n=7) after one-dose of MK2206 during week 1 (mean increase ALC: 35%) as well as reductions of plasma CCL3, CCL4 and CCL2 in the majority of the patients. A single dose-limiting toxicity (DLT) (febrile neutropenia and hemolytic anemia) was observed at dose level 1 (90 mg weekly) among 6 patients treated at this dose. Two patients with dose-limiting toxicities at dose level 2 (135 mg weekly) were observed where one patient had a rash and one patient had dehydration and febrile neutropenia among three patients treated at this dose. Accordingly, the 90 mg once weekly dose was determined to be the MTD for phase 2 trial testing. The most frequent grade 3 or 4 adverse events observed to date were neutropenia (44%) including febrile neutropenia (22%), rash (22%), diarrhea (22%), nausea and vomiting (11%), dehydration (11%), hemolytic anemia (11%) and thrombocytopenia (11%). The frequency of cytopenias was similar to the published German experience with BR (50% grade 3 or 4 hematological toxicities compared to 44% in N1087) in relapsed CLL patients (Fischer, JCO 2011). The median number of cycles received was 6 (range 1-6). Using an intent to treat analysis, two patients achieved complete response (CR, n= 2, 22%), one patient achieved nodular partial response (nPR, n=1, 11%) and five patients achieved a partial response (PR, n=5, 56%). The overall response rate (ORR) is 89%. Conclusion The Akt inhibitor MK2206 in combination with BR is well tolerated in patients with relapsed/refractory CLL. Single dose of MK2206 inhibits Akt phosphorylation, mobilizes leukemic cells and decreases plasma cytokines involved in BCR signals. The preliminary efficacy of this combination demonstrated promising results with a 89% ORR and 22% CR albeit in the small phase 1 cohort. These results compare favorably to BR alone (9% CR and 59% ORR) in relapsed/refractory CLL patients. Phase 2 testing of this combination is now underway. Acknowledgment This work was supported by the funding from NCI grant K23CA160345 (WD), NCI grant CA95241 (NEK) and Alliance for Clinical Trials in Oncology (CA025224 and CA33601). Disclosures: Off Label Use: MK2206, used in a phase 1 trial of relapsed CLL disease. Shanafelt:Genentech: Research Funding; Glaxo-Smith-Kline: Research Funding; Cephalon: Research Funding; Hospira: Research Funding; Celgene: Research Funding; Polyphenon E International: Research Funding. Zent:Novartis: Research Funding; GlaxSmithKline: Research Funding; Biothera: Research Funding; Genzyme: Research Funding; Genentech : Research Funding. Reeder:Celgene: Research Funding; Novartis: Research Funding; Millenium: Research Funding.

Abstract Background Although its prevalence is not well defined, transformation to Hodgkin lymphoma (HL) is a rare but well recognized complication in patients with CLL. Prior studies have reported a median survival of 0.8-1.7 years in these patients. Prior therapy of CLL, especially with purine analogs, has been shown to have adverse impact on survival after development of HL. We used the Mayo Clinic CLL database to describe outcomes of CLL patients seen at our institution who developed HL. Methods The Mayo Clinic CLL database includes all consenting patients with a pathologic diagnosis of CLL. Patients who developed biopsy-proven HL were included in this analysis. For patients referred from an outside institution, pathology review at Mayo Clinic was mandatory to be included. Clinical characteristics, therapy and overall survival (OS) were analyzed for all HL patients. Results Among 3124 CLL patients seen at Mayo Clinic from 1/1995 to 7/2011, 26 developed HL. In a nested cohort of 1644 patients who were seen within 12 months of CLL diagnosis and followed prospectively, the prevalence of HL was 0.05%/year (10 year risk=0.5%). All 26 patients had classical HL. The median duration between CLL diagnosis and development of HL was 6.2 years (range, 0-24.5 years). The median age at diagnosis of HL was 68 years (range, 45-88 years) and 21 (81%) were male. At the time of HL diagnosis, the median WBC count was 7.8 x 109/L (range, 1.3-87.3), median hemoglobin was 11 gm/dL (range, 7.2-13), median platelet count was 220x109/L (range, 53-627), median serum lactate dehydrogenase was 249 U/L (range, 133-658), and median serum albumin was 3.4 gm/dL (range, 2.6-4.2). According to the Ann Arbor staging system for HL, 10 (38%) were Stage II, 2 (8%) were Stage III, 11 (42%) were Stage IV, and undetermined in 3 (12%) patients. Sixteen patients (61%) received HL therapy with doxorubicin, bleomycin, vinblastine and dacarbazine (ABVD), seven (27%) received other chemotherapy, and treatment was unknown in 3 (12%) patients. No patient underwent stem cell transplantation as therapy for HL. After a median follow-up of 8.7 years from CLL diagnosis date, 16 (61%) patients have died. The median OS from date of HL diagnosis was 3.9 years (95% CI, 1.0 – 5.0 years). The International Prognostic score (IPS) for HL, originally proposed by Hasenclever in 1998, identified seven prognostic factors: serum albumin <4 gm/dL, hemoglobin <10.5 gm/dL, male sex, age >45 years, stage IV disease, WBC≥15 x 109/L, and lymphocytopenia in patients with newly diagnosed HL. When we applied these prognostic parameters (available in 22/26 patients, 85% in our cohort), the IPS score predicted median survival as follows: score of ≤2 (18% of the patients), median survival not reached; score of 3 (23% of the patients), 6.2 years; score of 4 (36% of the patients), 2.4 years; and score ≥5 (23% of the patients), 0.3 years (p-value=0.005, Figure 1). In contrast, the Richter syndrome prognostic score developed for CLL patients who transform to diffuse large B-cell lymphoma failed to predict survival in these patients (Tsimberidou, JCO, 2006). Of the 26 patients with HL, 16 (61%) had received therapy for their CLL prior to developing HL, including 12 (46%) who had received more than one line of therapy. Purine analogs had been administered for treatment of CLL prior to development of HL in 13/26 (50%) patients. The median survival of HL patients who had previously received CLL therapy was significantly worse compared to those who were untreated for CLL (2.8 years vs. 7.6 years, p-value=0.02). There was a trend toward shorter survival for HL patients who had received previous purine analog therapy for CLL compared to those who received alternate therapies (1.8 years vs. 5 years, p-value: p-value=0.07). Of the 9 HL biopsy samples in which Epstein Barr virus (EBV) in-situ hybridization studies were performed, EBV was detected in 6 (67%) patients. No association was observed between prior purine analog therapy and EBV status (p-value=1.0). There was no difference in survival according to the EBV status of HL (p-value=0.33). Conclusion The 10 year incidence of transformation to Hodgkin transformation among patients with newly diagnosed CLL is 0.5% (∼1/200 CLL patients). In this single-institution analysis, median survival of CLL patients who developed Hodgkin transformation of CLL was approximately 4 years after HL diagnosis. The IPS accurately predicted survival in our cohort of HL patients. Disclosures: Zent: Novartis: Research Funding; GlaxSmithKline: Research Funding; Biothera: Research Funding; Genzyme: Research Funding; Genentech : Research Funding. Shanafelt:Glaxo-Smith-Kline: Research Funding; Cephalon: Research Funding; Hospira: Research Funding; Celgene: Research Funding; Polyphenon E International: Research Funding; Genentech: Research Funding.