Microparticles (size range 0.1-500 pm), produced from naturally occurring or synthetic polymers, are physically and chemically more stable than liposomes and have the capability to carry a higher drug load. Natural synthetic biocompatible and biodegradable polymers (chitosan, PLGA, PLA, poly(butylcyanoacrylate), and poly(lactic-co-lysine graft lysine) are commonly employed in producing such particles (Smola et al. 2008; Kaur et al. 2012). These particles can be coated with PEG to enhance their sustained-release property. Other techniques, including addition of dipalmitoylphosphatidylcholine, chitosan, or hydroxypropylcellulose, also prolong residence of particles in the lung. Microparticles produced by these techniques have higher stability, are able to carry a higher drug load, release drug slowly, and have longer pharmacological activity than liposomal formulations (Feng et al. 2003). The morphology, size, and porosity of these particles could be modulated for specific pulmonary indications (Feng et al. 2003). Docetaxel-loaded microspheres demonstrate sustained drug release, increased lung bioavailability, and reduced systemic toxicity (Wang et al. 2014).