The polymer carrier carters the drug to target, reduces the metabolic drug degradation, accounts for sustained release, increases the activity of the active pharmaceutical ingredient and reduces the side effects of the drug. The total market for nanotechnology-enabled drug delivery2 KOS 953 was estimated to be $26 billion by 2012 and further projected to the sky rocket $220 billion by 2015 with an average annual increase of 37%. The current trend in Nanomedicine3 drug formulations (Fig. 2) works with the nanoformulation of existing generic drug and hence reducing the cost of drug development into many folds. The main aim of the nano-formulations is to fine-tune the normal metabolic profile of proven established drug molecules by significantly improving the drug efficacy, sustained release and reduced side effects.

Abraxane? is a marketed product4 of Abraxis and is a similar nanoformulation that has brought in up to 70% increase of Paclitaxel delivery against solvent based Paclitaxel delivery for breast cancer and non-small-cell lung cancer. Abraxis Bio Sciences has invented this first-in-class nanoformulation with blockbuster Paclitaxel (Taxol) drug from Bristol-Meyers-Squibb Company. Nanotechnology based drug delivery systems include nanoemulsions, lipid or polymeric nanoparticles, liposomes and nanofibers. Polymeric nanoparticular drug delivery systems have the advantages of cheaper cost, scalability, targeted delivery, biodegradability, biocompatibility, sustainability in release of encapsulated drug and improved efficacy.

The biopolymers of carbohydrate origin such as Chitosan, Alginate and proteinous origin such as albumin, gelatin and silk proteins have added advantage over the synthetic polymers when there can be a compromise for long lasting stability. At the same time there are many synthetic polymers that are biocompatible and comparatively less biodegradable in comparison with natural polymers, which include polylactides (PLA), polyglycolides (PGA), poly(lactide-co-glycolides) (PLGA), polyorthoesters and polyanhydrides. These nanoparticulate drug delivery systems modify the normal pharmacokinetic profile of encapsulated therapeutic drug and help in targeted and sustained release of drug. Thus they overcome the barrier of systemic delivery which is the only way of administration for a wide range of active pharmaceutical ingredients.

Nanotechnology based drug delivery systems can be classified under three major categories which can be further subdivided as tabulated (Table 1). Of these various drug delivery technologies some of which are marketed and a few in clinical trials (Table 2),5 our main interest is the nanoparticulate drug delivery which in general Carfilzomib falls in to the following categories based on their synthesis method.6-8 Figure 1. Projected timelines for Nanopharma ��from research to market��. Figure 2. Existing Nanomedicine in clinical usage. Table 1. Nanotechnology based drug delivery systems classification Table 2.