This pilot study will evaluate whether the administration of roflumilast inhibits the activity of PDE4 and results in the modulation of AKT/mTOR pathways in patients with B-cell hematologic malignancies. Peripheral blood samples will be collected for the purpose of determining the pharmacodynamics of roflumilast on PDE4 activity and on biomarkers as related to GC resistance. Samples are obtained at baseline prior to starting study treatment, on Day 8 before the administration of the Day 8 study drugs (prednisone and roflumilast), and on Day 15. If a bone marrow biopsy is also performed prior to study treatment or at any time during treatment, a sample will be sent for analysis. Normal PBMC (and bone marrow when it is obtained) will be examined for changes in key targets related to the inhibition of PDE4 and potential reversal of glucocorticoid resistance. Biomarker blood samples will be analyzed in order to characterize the pharmacodynamics of roflumilast alone and in combination with prednisone on PDE4 activity and on biomarkers, such as phospho-AKT, phosphorylation levels of mTOR targets.