Decrease in JAK2 V617F allele burden is not a prerequisite to clinical response in patients with polycythemia vera.

BACKGROUND: Although reduction in the JAK2(V617F) allele burden (%V617F) has been suggested as a criterion for defining disease response to cytoreductive therapy in polycythemia vera, its value as a response monitor is unclear. The purpose of this study is to determine whether a reduction in %V617F in polycythemia vera is a prerequisite to achieving hematologic remission in response to cytoreductive therapy. DESIGN AND METHODS: We compared the clinical and hematologic responses to change in %V617F (molecular response) in 73 patients with polycythemia vera treated with either interferon (rIFNα-2b: 28, Peg-rIFNα-2a: 18) or non-interferon drugs (n=27), which included hydroxyurea (n=8), imatinib (n=12), dasatinib (n=5), busulfan (n=1), and radioactive phosphorus (n=1). Hematologic response evaluation employed Polycythemia Vera Study Group criteria, and molecular response evaluation, European Leukemia Net criteria. RESULTS: Of the 46 treated with interferon, 41 (89.1%) had a hematologic response, whereas only 7 (15.2%) had a partial molecular response. Of the 27 who received non-interferon treatments, 16 (59.3%) had a hematologic response, but only 2 (7.4%) had a molecular response. Median duration of follow up was 2.8 years. Statistical agreement between hematologic response and molecular response was poor in all treatment groups. CONCLUSIONS: Generally, hematologic response was not accompanied by molecular response. Therefore, a quantitative change in %V617F is not required for clinical response in patients with polycythemia vera.

An Expanded Treatment Protocol of Panobinostat Plus Bortezomib and Dexamethasone in Patients With Previously Treated Myeloma.

BACKGROUND: Panobinostat was recently approved by the US Food and Drug Administration and European Commission in combination with bortezomib and dexamethasone for patients with multiple myeloma who have received ≥ 2 regimens, including bortezomib and an immunomodulatory drug. The PANEX (panobinostat expansion) treatment protocol provided access to panobinostat and gathered additional safety data before commercial availability. PATIENTS AND METHODS: In treatment phase 1, patients received panobinostat 20 mg 3 times per week plus bortezomib 1.3 mg/m2 twice weekly with dexamethasone 20 mg on the days of and after bortezomib treatment. Patients with no change or better in treatment phase 1 proceeded to treatment phase 2, when bortezomib was reduced to once weekly. Unlike in the phase III trial, PANORAMA-1 (panobinostat or placebo with bortezomib and dexamethasone in patients with relapsed multiple myeloma), bortezomib could be administered either subcutaneously or intravenously. RESULTS: Thirty-nine patients with a median number of previous treatments of 4 (range, 1-12) were enrolled; most received subcutaneous bortezomib (87%). The overall response rate (partial response or better) was 56%. Grade 3/4 adverse events included thrombocytopenia (47%), fatigue (31%), dehydration (26%), and diarrhea (18%). Among the patients who received subcutaneous bortezomib, relatively low rates of peripheral neuropathy (all grade, 15%) and notable grade 3/4 adverse events (thrombocytopenia, 47%; diarrhea, 12%) were observed. CONCLUSION: Overall, data from the PANEX trial support regulatory approval of panobinostat plus bortezomib and dexamethasone and suggest the potential tolerability benefits of subcutaneous bortezomib in this regimen.

Dose and Schedule Determine Distinct Molecular Mechanisms Underlying the Efficacy of the p53-MDM2 Inhibitor HDM201.

Activation of p53 by inhibitors of the p53-MDM2 interaction is being pursued as a therapeutic strategy in p53 wild-type cancers. Here, we report distinct mechanisms by which the novel, potent, and selective inhibitor of the p53-MDM2 interaction HDM201 elicits therapeutic efficacy when applied at various doses and schedules. Continuous exposure of HDM201 led to induction of p21 and delayed accumulation of apoptotic cells. By comparison, high-dose pulses of HDM201 were associated with marked induction of PUMA and a rapid onset of apoptosis. shRNA screens identified PUMA as a mediator of the p53 response specifically in the pulsed regimen. Consistent with this, the single high-dose HDM201 regimen resulted in rapid and marked induction of PUMA expression and apoptosis together with downregulation of Bcl-xL in vivo Knockdown of Bcl-xL was identified as the top sensitizer to HDM201 in vitro, and Bcl-xL was enriched in relapsing tumors from mice treated with intermittent high doses of HDM201. These findings define a regimen-dependent mechanism by which disruption of MDM2-p53 elicits therapeutic efficacy when given with infrequent dosing. In an ongoing HDM201 trial, the observed exposure-response relationship indicates that the molecular mechanism elicited by pulse dosing is likely reproducible in patients. These data support the clinical comparison of daily and intermittent regimens of p53-MDM2 inhibitors.Significance: Pulsed high doses versus sustained low doses of the p53-MDM2 inhibitor HDM201 elicit a proapoptotic response from wild-type p53 cancer cells, offering guidance to current clinical trials with this and other drugs that exploit the activity of p53. Cancer Res; 78(21); 6257-67. ©2018 AACR.

Estimating the Economic Impact of Adding Panobinostat to a U.S. Formulary for Relapsed and/or Refractory Multiple Myeloma: A Budget Impact and Cost-Benefit Model.

BACKGROUND: Multiple myeloma is an incurable B-cell malignancy with a natural history that involves alternating periods of remission and subsequent relapse. For relapsed and/or refractory multiple myeloma (RRMM), the typical patient currently receives more lines of therapy than has been feasible in the past, translating into longer progression-free survival (PFS). Consequently, cost issues have become more prominent because patients may be offered newer and more expensive therapies during a more prolonged overall treatment course. OBJECTIVE: To estimate the economic impact of adding panobinostat to a U.S. health plan formulary as a treatment option with bortezomib and dexamethasone for patients with RRMM previously treated with a proteasome inhibitor (PI) and immunomodulatory drug (IMiD), using a budget impact and cost-benefit model. METHODS: Total costs of commonly used salvage therapy regimens were combined with market share data and population prevalence estimates of RRMM to yield the total cost of treatment, from the perspective of a U.S. third-party payer (commercial or Medicare) with a time horizon of 1 year. Comparator treatment regimens included bortezomib-dexamethasone, lenalidomide-dexamethasone, lenalidomide-bortezomib-dexamethasone, carfilzomib monotherapy, carfilzomib-lenalidomide-dexamethasone, and pomalidomide-dexamethasone. Costs (2015 U.S. dollars) included drug costs for oral oncology agents, medical and administration costs for injectable oncology agents, costs of adverse event (AE) prophylaxis and monitoring, and costs of grade 3/4 AEs. RESULTS: In a hypothetical health plan with 1 million members, the annual number of RRMM patients with previous PI and IMiD treatments was estimated at 16 and 118 for a commercial and Medicare plan, respectively. Introduction of panobinostat as part of the panobinostat-bortezomib-dexamethasone regimen was not expected to result in a substantial budget impact to either commercial or Medicare plans, with an incremental cost < $0.01 per member per month. Panobinostat-bortezomib-dexamethasone had a low cost per treated patient per month without progression, owing to the minimal increase in expenditure over existing bortezomib-based regimens and long median PFS, compared with median duration of treatment. CONCLUSIONS: Adding panobinostat to a plan formulary as a treatment option is expected to be cost neutral (and potentially cost saving in the context of new and more expensive treatment regimens). With a low cost per month without progression, panobinostat-bortezomib-dexamethasone represents good value for the money. DISCLOSURES: Funding for this study was sponsored by Novartis, East Hanover, New Jersey. Bloudek and Kish are employees of Xcenda, a consulting company contracted by Novartis to conduct this analysis. Roy, Globe, and Kuriakose are employees of Novartis. Siegel is on the advisory boards and speaker's bureau of Celgene, Onyx/Amgen, Millennium/Takeda, and Novartis and is on the advisory boards of Merck. Jagannath is a consultant to Sanofi, Bristol-Meyers Squibb, and Celgene. Orloski is a contractor to Xcenda and provided medical writing support, which was funded by Novartis. Study design and concept were contributed by Bloudek, Roy, and Kish, assisted by Globe. Bloukek took the lead in data collection, along with Kish, and data interpretation was performed by Siegal, Jagannath, Globe, and Kuriakose. The manuscript was written primarily by Orloski, along with Roy and Kish, and revised by Roy, along with Siegal, Jagannath, Globe, Orloski, and Kuriakose.

Real-world treatment patterns and associated progression-free survival in relapsed/refractory multiple myeloma among US community oncology practices.

BACKGROUND: Evidence supporting optimal treatment sequencing in relapsed/refractory multiple myeloma (RRMM) patients requiring multiple therapy lines is lacking. METHODS: Using retrospective chart data, this study describes real-world RRMM treatment patterns and related progression-free survival (PFS) in US community oncology clinics. RESULTS: Bortezomib ± a non-immunomodulatory drug (IMiD), lenalidomide ± a non-proteasome inhibitor (PI), bortezomib + an IMiD were the most commonly used regimens in early lines of therapy. Median PFS was similar in 1(st) (11.1 months) and 2(nd) line (10.5) and decreased in lines 3 through 5 (3(rd): 7.9; 4(th): 7.2, 5(th): 5.4). Longest PFS (12.5 months) in first line was with bortezomib + ImiD; longest PFS in second line was with lenalidomide ± a non-PI was (13.2 months). CONCLUSIONS: Re-treatment with bortezomib was common; novel agents were reserved for later therapy lines. Overall, the observed PFS associated with real-world treatment sequences were shorter than those reported in clinical trials.

Allogeneic Transplantation for Patients With Advanced Myelofibrosis: Splenomegaly and High Serum LDH are Adverse Risk Factors for Successful Engraftment.

BACKGROUND: Thirty consecutive patients underwent hematopoietic stem cell transplantation for myelofibrosis (MF) at our institution. The median age at the time of transplant was 49 (range, 18-68) years, 74% of patients had advanced Dynamic International Prognostic Scoring System (DIPSS) scores, and 83% received reduced-intensity conditioning. PATIENTS AND METHODS: With a long follow-up of our patients, we analyzed disease and transplant variables that contributed to engraftment and outcomes. RESULTS: Neutrophil engraftment was achieved in 27 patients (90%) at a median time of 15 (range, 10-44) days, and 19 patients (63%) achieved platelet recovery at a median time of 18 (range, 8-100) days. Splenomegaly was associated with poor neutrophil engraftment (subdistributional hazard ratio [SHR], 0.42; 95% confidence interval [CI], 0.21-0.83; P = .01) and platelet engraftment (SHR, 0.18; 95% CI, 0.07-0.48; P < .001). Increased levels of lactate dehydrogenase (LDH) was associated with poor platelet engraftment (SHR, 0.39; 95% CI, 0.16-0.94; P = .04). The median follow-up for surviving patients was 49 (range, 3-155) months. The 1-year cumulative incidence of nonrelapse mortality (NRM) and relapse were respectively, 57% (95% CI, 29%-76%) and 25% (95% CI, 7%-48%). Increased levels of LDH was associated with high NRM (SHR, 2.82; 95% CI, 1.08-7.35; P = .03). The 4-year overall survival (OS) and relapse-free survival (RFS) were 44% (95% CI, 29%-67%) and 37% (95% CI, 23%-61%), respectively. In the multivariable model, splenomegaly and Eastern Cooperative Oncology Group (ECOG) performance status (PS) > 1 were associated with worse OS (hazard ratio [HR], 5.40; 95% CI, 1.19-24.56); P = .03) and RFS (HR, 3.78; 95% CI, 1.01-14.06; P < .05), respectively. ECOG PS > 1 was also associated with worse RFS (HR, 5.00; 95% CI, 1.31-19.14; P = .02). In this patient group with advanced disease, DIPPS score, Lille score, Janus-Associated Kinase V617F (JAK2 V617F) mutation status, and donor type did not predict transplant outcome. CONCLUSION: We confirm curative potential, but high NRM of allogeneic transplant for advanced MF.

Estimating the Costs of Therapy in Patients with Relapsed and/or Refractory Multiple Myeloma: A Model Framework.

BACKGROUND: Multiple myeloma is a progressive cancer for which there is no cure. Despite treatment, almost all patients eventually experience periods of disease relapse and remission. With the increasing use of novel therapies, including bortezomib, lenalidomide, carfilzomib, pomalidomide, and panobinostat, benchmarks for assessing the value of these therapies in treating patients with relapsed or refractory multiple myeloma (RRMM) are needed for physicians and payers alike. OBJECTIVES: To develop a model framework and to calculate an annual estimate of the total costs per patient for the treatment of patients with RRMM using 7 common treatment regimens, including bortezomib plus dexamethasone; panobinostat, bortezomib, and dexamethasone; lenalidomide plus dexamethasone; lenalidomide, bortezomib, and dexamethasone; carfilzomib; carfilzomib, lenalidomide, and dexamethasone; and pomalidomide plus dexamethasone. METHODS: The expenditures for drugs and their administration, for prophylaxis and adverse event monitoring, and for the treatment of grade 3 or 4 adverse events were included in the calculations of the total pharmacy and medical costs. The drug costs were based on published pricing and labeled dosing schedules; the adverse event prophylaxis and monitoring costs were obtained from peer-reviewed publications; and the adverse event incidence rates were obtained from each regimen's prescribing information and from clinical trials. All the costs were summed over the duration of therapy for which the drugs were administered and were calculated separately for commercial and Medicare plans. The duration of therapy for each regimen was the time for which a patient had to be receiving the regimen to obtain 12 months of progression-free survival based on the duration-of-therapy to progression-free survival ratio observed from published clinical trials and/or the drug's labeling. RESULTS: The pharmacy costs were highest for pomalidomide plus dexamethasone, whereas the medical costs were highest for the combination of carfilzomib, lenalidomide, and dexamethasone. The total cost associated with available treatments for RRMM was highest for regimens that included lenalidomide (approximate range, $126,000-$256,000). Only bortezomib plus dexamethasone and the combination of panobinostat, bortezomib, and dexamethasone had total costs that were lower than $125,000 per patient. CONCLUSION: This study represents the first model developed to comprehensively estimate the costs of managing RRMM with all currently approved and guideline-recommended regimens in the United States. As such, it provides the framework and basis for further budget impact analyses and for cost-effectiveness comparisons with these regimens.