Pegaptanib is a selective vascular endothelial growth factor (VEGF) antagonist indicated for the treatment of neovascular (wet) age-related macular degeneration. Pegaptanib is an aptamer, a pegylated modified single-stranded oligonucleotide, which adopts a threedimensional conformation that enables it to bind to extracellular VEGF. Pegaptanib specifically binds to the 165 isoform of VEGF, a protein that plays a critical role in angiogenesis (the formation of new blood vessels) and increased permeability (leakage from blood vessels), two of the primary pathological processes responsible for the vision loss associated with neovascular age-related macular degeneration. Pegaptanib is administered in a 0.3 mg dose once every six weeks by intravitreal injection. An intravitreal injection is one that is administered directly into the eye, more specifically, into the vitreous humour, or the jelly-like fluid within the eye.

Colesevelam (trade name Welchol) a non-absorbed, polymeric, lipid-lowering agent intended for oral administration. Colesevelam is poly(allylamine hydrochloride) cross-linked with epichlorohydrin and alkylated with 1-bromodecane and (6-bromohexyl)-trimethylammonium bromide. Colesevelam hydrochloride is a hydrophilic, water-insoluble polymer that is not hydrolyzed by digestive enzymes and is not absorbed. Colesevelam is part of a class of drugs known as bile acid sequestrants. Colesevelam hydrochloride, the active pharmaceutical ingredient in Welchol, is a non-absorbed, lipid-lowering polymer that binds bile acids in the intestine, impeding their reabsorption. As the bile acid pool becomes depleted, the hepatic enzyme, cholesterol 7-α-hydroxylase, is upregulated, which increases the conversion of cholesterol to bile acids. This causes an increased demand for cholesterol in the liver cells, resulting in the dual effect of increasing transcription and activity of the cholesterol biosynthetic enzyme, HMG-CoA reductase, and increasing the number of hepatic LDL receptors. These compensatory effects result in increased clearance of LDL-C from the blood, resulting in decreased serum LDL-C levels. Colesevelam is indicated as an adjunct to diet and exercise to reduce elevated low-density lipoprotein cholesterol (LDL-C) in patients with primary hyperlipidemia as monotherapy and to improve glycemic control in adults with type 2 diabetes mellitus, including in combination with a statin. The expanded use of colesevelam in adults with type 2 diabetes mellitus is an example of drug repositioning.

Enoxaparin is a low molecular weight heparin used as anticoagulant medication to treat and prevent deep vein thrombosis (DVT) and pulmonary embolism (PE) including during pregnancy and following certain types of surgery. Enoxaparin is a depolymerized derivative of Unfractionated heparin produced by controlled depolymerization using alkaline hydrolysis of the heparin benzylic ester. Like Unfractionated heparin, its major anticoagulant effect is mediated by interaction with antithrombin III, which in turn inactivates serine proteases like factors IIa (thrombin), IXa and Xa. Therefore, enoxaparin indirectly inhibits the conversion of prothrombin to thrombin and reduces the thrombin-mediated conversion of fibrinogen to fibrin, thus preventing clot formation. Among parenteral anticoagulants, enoxaparin stands out for certain major advantages: rapid onset of action, higher bioavailability, once- or twice-daily dosing that can be administered by patients at home without any need for monitoring, and no reported association with catheter thrombosis. Enoxaparin has been shown to be a safe and effective drug in a wide variety of thromboembolic conditions, and two decades of available data have undoubtedly inspired significant confidence. Although these properties make it a preferred option in a wide range of clinical disorders, lack of reliable antidote and accumulation in renal dysfunction are major concerns associated with its use, which are shared, apart from Unfractionated heparin, by most other available anticoagulants.