Biological Activity

Flumethasone pivalate is a glucocorticoid receptor agonist used in studies on plasma transcortin binding. It binds to the nucleus causing a variety of genetic activations and repressions. The anti-inflammatory action of flumethasone is thought to involve lipocortins and phospholipase A2 inhibitory proteins, which results in the inhibition of arachidonic acid and the control of prostaglandin and leukotriene biosynthesis. Flumethasone suppresses the immune system due to a decrease in the function of the lymphatic system, a reduction in immunoglobulin and complement concentrations, the precipitation of lymphocytopenia, and interference with antigen-antibody binding.

Manufacturing Process

To approximately 1.3 g of hydrogen fluoride contained in a polyethylene bottle and maintained at -60°C was added 2.3 ml of tetrahydrofuran and then a solution of 500 mg (0.0012 mol) of 6α-fluoro-9β,11β-epoxy-16α-methyl- 17α,21-dihydroxy-1,4-pregnadiene-3,20-dione-21-acetate in 2 ml of methylenechloride. The steroid solution was rinsed in with an additional 1 ml of methylene chloride. The light red colored solution was then kept at approximately -30°C for 1 hour and at -10°C for 2 hours. At the end of this period it was mixed cautiously with an excess of cold sodium bicarbonate solution and the organic material extracted with the aid of additional methylene chloride. The combined extracts were washed with water, dried over anhydrous sodium sulfate and concentrated to approximately 35 ml. The solution was chromatographed over 130 g of Florisil anhydrous magnesium silicate. The column was developed with 260 ml portions of hexanes (Skellysolve B) containing increasing proportions of acetone. There was thus eluted 6α,9α-difluoro-11β,17α,21-trihydroxy-16α-methyl-1,4-pregnadiene- 3,20-dione 21-acetate which was freed of solvent by evaporation of the eluate fractions.

Therapeutic Function

Glucocorticoid, Antiinflammatory

Veterinary Drugs and Treatments

Flumethasone injection (Flucort?) is labeled in horses as indicated for: 1) Musculoskeletal conditions due to inflammation, where permanent structural changes do not exist, such as bursitis, carpitis, osselets and myositis. Following therapy an appropriate period of rest should be instituted to allow a more normal return to function of the affected part. 2) In allergic states such as hives, urticaria and insect bites. Flumethasone injection (Flucort?) is labeled in dogs as indicated for: 1) Musculoskeletal conditions due to inflammation of muscles or joints and accessory structures, where permanent structural changes do not exist, such as arthritis, osteoarthritis, the disc syndrome and myositis. In septic arthritis appropriate antibacterial therapy should be concurrently administered. 2) In certain acute and chronic dermatoses of varying etiology to help control the pruritus, irritation and inflammation associated with these conditions. The drug has proven useful in otitis externa in conjunction with topical medication for similar reasons. 3) In allergic states such as hives, urticaria and insect bites. 4) Shock and shock-like states, by intravenous administration. Flumethasone injection (Flucort?) is labeled in cats as indicated for certain acute and chronic dermatoses of varying etiology to help control the pruritus, irritation and inflammation associated with these conditions. Glucocorticoids have been used in an attempt to treat practically every malady that afflicts man or animal, but there are three broad uses and dosage ranges for use of these agents. 1) Replacement of glucocorticoid activity in patients with adrenal insufficiency, 2) as an antiinflammatory agent, and 3) as an immunosuppressive. Among some of the uses for glucocorticoids include treatment of: endocrine conditions (e.g., adrenal insufficiency), rheumatic diseases (e.g., rheumatoid arthritis), collagen diseases (e.g., systemic lupus), allergic states, respiratory diseases (e.g., asthma), dermatologic diseases (e.g., pemphigus, allergic dermatoses), hematologic disorders (e.g., thrombocytopenias, autoimmune hemolytic anemias), neoplasias, nervous system disorders (increased CSF pressure), GI diseases (e.g., ulcerative colitis exacerbations), and renal diseases (e.g., nephrotic syndrome). Some glucocorticoids are used topically in the eye and skin for various conditions or are injected intra-articularly or intra-lesionally. The above listing is certainly not complete.

Application

Flumethasone is a topical corticosteroid of the glucocorticoid class used in the treatment of skin disorders where it reduces inflammation. Flumethasone is insoluble in water. Flumethasone pivalate is a topical difluorinated corticosteroid ester with anti-inflammatory, antipruritic and vasoconstrictive properties. A prompt decrease in inflammation, exudation and itching is experienced after application. It is commonly used in veterinary practice and has been used in cortisol assays to study early porcine conceptus development.