| Bioactivity | Roflumilast (APTA-2217) is a selective PDE4 inhibitor with IC50s of 0.7, 0.9, 0.7, and 0.2 nM for PDE4A1, PDEA4, PDEB1, and PDEB2, respectively, without affecting PDE1, PDE2, PDE3 or PDE5 isoenzymes from various cells. | ||||||||||||
| Invitro | Roflumilast does not affect PDE enzymes apart from PDE4, and is a subnanomolar inhibitor of most PDE4 splicing variants tested. It showed no PDE4 subtype selectivity apart from PDE4C (4C1, IC50=3 nM; 4C2, IC50=4.3 nM), which is inhibited with a slightly lower potency[2]. Roflumilast is a potent and selective PDE4 inhibitor. Roflumilast is a monoselective PDE4 inhibitor since it does not affect other PDE isoenzymes, including PDE1, PDE2, PDE3, and PDE5 up to 10,000-fold higher concentrations. Roflumilast inhibits human neutrophil functions. Roflumilast inhibits TNFα synthesis in monocyte-derived dendritic cells. Rolfumilast inhibits proliferation and cytokine synthesis in CD4+ T cells. Proliferation is inhibited to a maximum of about 60% by Roflumilast with a potency (IC30) of 7 nM[3]. | ||||||||||||
| In Vivo | Animal studies with Roflumilast demonstrated that it reduced the accumulation of neutrophils in bronchoalveolar lavage fluid following short-term exposure of guinea pigs, mice or rats to tobacco smoke, and following exposure of rats to a combination of tobacco smoke and bacterial lipopolysaccharide, and abolished the lung parenchymal influx of inflammatory cells seen in rats exposed to tobacco smoke for 7 months[2]. Roflumilast blocks COPD progression in pIgR−/− mice. For these studies, 9-month-old WT or pIgR−/− mice are treated daily by oral gavage with 100 μg of Roflumilast (5 μg/g) or vehicle (4% methylcellulose, 1.3% PEG400) for 3 months and lungs are harvested at 12 months of age. Unlike pIgR−/− mice treated with vehicle, mice treated with Roflumilast had no progression of small airway wall remodelling after starting treatment. Strikingly, 12-month-old pIgR−/− mice treated with Roflumilast had reduced indices of emphysema compared with 9-month-old pIgR−/− mice, indicating that Roflumilast not only blocks progression of emphysema in this model but apparently facilitates some resolution of the emphysematous destruction of lung parenchyma[4]. | ||||||||||||
| Name | Roflumilast | ||||||||||||
| CAS | 162401-32-3 | ||||||||||||
| Formula | C17H14Cl2F2N2O3 | ||||||||||||
| Molar Mass | 403.21 | ||||||||||||
| Appearance | Solid | ||||||||||||
| Transport | Room temperature in continental US; may vary elsewhere. | ||||||||||||
| Storage |
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| Reference | [1]. Hatzelmann A, et al. The preclinical pharmacology of roflumilast--a selective, oral phosphodiesterase 4 inhibitor in development for chronic obstructive pulmonary disease. Pulm Pharmacol Ther. 2010 Aug;23(4):235-56. [2]. Rabe KF. Update on roflumilast, a phosphodiesterase 4 inhibitor for the treatment of chronic obstructive pulmonary disease. Br J Pharmacol. 2011 May;163(1):53-67. [3]. Hatzelmann A, et al. Anti-inflammatory and immunomodulatory potential of the novel PDE4 inhibitor roflumilast in vitro. J Pharmacol Exp Ther. 2001 Apr;297(1):267-79. [4]. Richmond BW, et al. Airway bacteria drive a progressive COPD-like phenotype in mice with polymeric immunoglobulin receptor deficiency. Nat Commun. 2016 Apr 5;7:11240. [5]. Ding H, et al. Treatment of obesity-associated overactive bladder by the phosphodiesterase type-4 inhibitor roflumilast. Int Urol Nephrol. 2017 Jul 29. |