Therapies, enzyme Therapeutics

Myocardial infarction -thrombolytic therapy [ENZYME APPLICATIONS - THERAPEUTIC] (Vol 9)... 

In addition to being necessary for all forms of life, biopolymers, especially enzymes (proteins), have found commercial applications in various analytical techniques. See also Automated Instrumentation Clinical Chemistry Automated Instrumentation Hematology and Biosensors. In synthetic processes (see also Enzymes in Organic Synthesis) and in prescribed therapies (See also Enzyme Therapeutic and Vitamin), Other naturally occurring biopolymcrs having significant commercial importance aie the cellulose derivatives, e.g., cotton and wood, which are complex polysaccharides. 

The potential utility of enzymes as pharmaceuticals was noted many decades ago, and since then, nearly two dozen enzymes have been developed to treat a variety of diseases. Almost all enzyme therapies developed to date are used to deal with a loss of function defect (a mutation that diminishes activity, a low level of production, a deletion). Hence, most enzyme drugs are used as enzyme replacement therapies (ERT) for relatively rare, inborn errors of metabolism (lEMs). As a result, many enzyme therapeutics fall under the FDA s Orphan Drug Designation. However, a few enzyme therapies can also be used to treat much more common conditions such as cancer, heart attacks, and stroke. In the United States, the first enzyme to receive FDA approval was a tissue plasminogen activator called alteplase. This protein, which is now commonly used to treat strokes, was introduced in 1987 as Activase. Since then at least 16 other enzyme drugs have been introduced into the marketplace. Some of these are described in more detail below and in Table 6.1-3. 

Azathioprine, mycophenolate mofetil, and enteric-coated MPA are not metabolized through the CYP isozyme system therefore, they do not experience the same DDI profiles as cyclosporine, tacrolimus, and sirolimus. Azathioprine s major DDIs involve allopurinol, angiotensin-converting enzyme (ACE) inhibitors, aminosalicylates (e.g., mesalamine and sulfasalazine), and warfarin.11 The interaction with allopurinol is seen frequently and has clinical significance. Allopurinol inhibits xanthine oxidase, the enzyme responsible for metabolizing azathioprine. Combination of azathioprine and allopurinol has resulted in severe toxicities, particularly myelosuppression. It is recommended that concomitant therapy with azathioprine and allopurinol be avoided, but if combination therapy is necessary, the azathioprine doses must be reduced to one-third or one-fourth of the current dose. Use of azathioprine with the ACE inhibitors or aminosalicylates also can result in enhanced myelosuppression.11 Some case reports exist demonstrating that warfarin s therapeutic effects may be decreased by azathioprine.43-45... 

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