Of these polymers, one class of polymers has achieved significant commercial success in the pharmaceutical market. The polylactide (PLA) and polylactide-co-glycolide (PLGA) class of polymers are biodegradable, biocompatible, and nontoxic and have a long history of use [32]. In vivo, they are hydrolyzed into metabolic products that are easily eliminated from the

body. Initially approved for surgical use in humans by Inhibitors,research,lifescience,medical the US Food and Drug Administration, they have since been used to formulate a wide range of therapeutic agents [33, 34]. A few commercially available formulations using PLA or PLGA polymers include Lupron Depot, Somatuline LA, and Trelstar Depot [35]. These polymers have been shown to be efficacious in the delivery of biologically active agents and also improve patient Inhibitors,research,lifescience,medical compliance by eliminating the need for frequent administration [36]. PLGA polymers are well suited for controlled delivery of drugs via the parenteral route as they exhibit good mechanical properties and demonstrate predictable degradation kinetics. Notably, polymeric microspheres Inhibitors,research,lifescience,medical prepared using PLGA have been successful in ensuring sustained release of therapeutic agents for various drugs [37]. Several examples

in literature discuss their effectiveness in providing targeted drug levels in vivo, for long periods of time [38–40]. For this reason, they are popular as delivery vehicles for drugs where sustained release is desired for extended intervals, ranging from a few Inhibitors,research,lifescience,medical weeks to several Olaparib chemical structure months [41, 42]. These polymers are also used in marketed injectable formulations as carriers to deliver antipsychotic drugs and are noted to provide benefits over conventional oral therapy [43]. A striking benefit of using PLGA polymers to deliver atypical antipsychotics Inhibitors,research,lifescience,medical includes a reduction in dosing frequency leading to measurable

increase in adherence to treatment regimens in a schizophrenic patient population [44, 45]. In general, the success of PLGA polymers as delivery systems is due to the fact that polymer properties are well understood and can be customized to afford sustained drug release. For instance, selection of copolymers of various lactide:glycolide with variable Brefeldin_A molecular weights is an effective way to control polymer degradation rate and drug release. By changing the www.selleckchem.com/products/wortmannin.html composition of lactide or glycolide in the copolymer, a wide range of degradation rates can be obtained. An increase in the more hydrophobic lactide moiety ensures a slower degradation rate of the PLGA polymer leading to extended duration of drug release [46]. Similarly, utilization of a higher molecular weight copolymer increases degradation times leading to prolonged drug release. Additional properties that can be varied include polymer crystallinity and glass transition temperature.