Roflumilast 0.3% Cream: a Phosphodiesterase 4 Inhibitor for the Treatment of Chronic Plaque Psoriasis.

BACKGROUND: Plaque psoriasis is a chronic dermatologic autoimmune disease that affects adults and children. Roflumilast 0.3% cream is currently the only topical phosphodiesterase 4 inhibitor indicated for the treatment of plaque psoriasis in patients 12 years or older. PHARMACODYNAMICS AND PHARMACOKINETICS: Roflumilast inhibits phosphodiesterase 4 inhibitor enzyme leading to the accumulation of cyclic adenosine monophosphate, which suppresses the inflammatory mediators interferon-γ and tumor necrosis factor-α. Roflumilast, applied once daily, reaches steady state by day 15 and has a half life of approximately 4 days in adults. Roflumilast undergoes extensive hepatic metabolism by cytochrome P450 enzymes and conjugation. Roflumilast is 99% bound to plasma proteins. CLINICAL TRIALS: Roflumilast efficacy and safety were evaluated in the DERMIS-1 and DERMIS-2 clinical trials. These identically designed, double-blind, vehicle-controlled phase 3 trials randomized 881 patients to roflumilast 0.3% cream or vehicle, applied once daily for 8 weeks. In DERMIS-1, the Investigator Global Assessment success rate was 42.4% with roflumilast 0.3% cream compared with 6.1% with the vehicle (32.3%-46.9%; P <0.001). Similarly, in DERMIS-2, the Investigator Global Assessment success rate was 37.5% with roflumilast 0.3% cream compared with 6.9% with the vehicle (20.8%-36.9%; P <0.001). Of 881 participants, 1% discontinued treatment with roflumilast cream due to adverse reactions compared with 1.3% treated with vehicle. Urticaria at the application site (0.3%) was the most common adverse reaction that led to discontinuation of roflumilast. THERAPEUTIC ADVANCE: To date, topical corticosteroids are the most commonly used agents to treat mild plaque psoriasis. Sensitive areas are often challenging to treat with existing topical therapy, including corticosteroids. Topical roflumilast has shown to be effective in treating sensitive areas, including skin folds, and may be an alternative to systemic therapy for some patients. The Food and Drug Administration approved topical roflumilast for the treatment of plaque psoriasis, including intertriginous areas, for patients 12 years or older.

Subtherapeutic INR due to warfarin interaction with smokeless tobacco.

We report an interesting case of warfarin resistance and subtherapeutic international normalized ratio (INR) in the setting of chronic smokeless tobacco use. A 33-year-old white male with a mechanical mitral valve failed to achieve therapeutic INR despite being on warfarin doses of up to 30 mg by mouth daily. The patient admits to chewing tobacco daily for the past 16 years. While evaluating potential causes of subtherapeutic INR, nonadherence, drug interactions, genetic polymorphisms, and dietary factors were considered. Subtherapeutic INR may be due to increased exposure to vitamin K from chewing tobacco. Tobacco is rich in vitamin K, and its chronic use may have caused the failure to attain a therapeutic INR. To our knowledge, there is only one other case of warfarin resistance resulting from smokeless tobacco described in published literature.