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die. This method of dispersing poorly soluble APIs in a car- rier system can increase dissolution rates and bioavailability. After cooling, the extruded mixture, or extrudate, generally consists of a single-phase matrix that can be milled to the desired particle size and incorporated into traditional tablets or capsules. Molecular encapsulation. In more difficult situations, cyclodextrins have been shown to increase water solubility, dissolution rate and, consequently, bioavailability of insolu- ble APIs. Cyclodextrins are cyclic oligosaccharides that have been shown to form inclusion complexes via molecular encapsulation that involves a guest molecule, i.e., an API, confined within the cavity of the host cyclodextrin mole- cule. This complexation depends largely on the dimensions of the cyclodextrin and the particular steric arrangement of the functional groups of the API, which leads to a relatively hydrophilic exterior and a hydrophobic interior within the host molecule. These complexes can be formed by a number of standard processing techniques, including blending, pre- cipitation, co-milling, and spray drying. T&C References Bajaj, H., Bisht, S., Yadav, M., and Singh, V. Bio- availability enhancement: A review. International Journal of Pharma and Bio Sciences, 2(2), 202-216. Beg, S., Swain, S., Rizwan, M., Irfanuddin, M., and Malini, D.S. Bioavailability enhancement strategies: Basics, formulation approaches and regulatory considera- tions," Current Drug Delivery, 8(6) 2011, 692-701. Crew, M. The second quadrant—A new year for sol- ubility enhancement. Drug Dev Delivery (14)1 2014, 22-25. FDA. Draft Guidance for Industry: Bioavailability and bioequivalence studies submitted in NDAs or INDs, General Considerations. March 2014. FDA. Draft Guidance for Industry: Waiver of in vivo bioavailability and bioequivalence studies for immediate- release solid oral dosage forms based on a Biopharmaceutics Classification System. May 2015. Hetal, T., Bindesh, P., Sneha, T. A review of techniques for oral bioavailability enhancements of drugs. International Journal of Pharmaceutical Sciences Review and Research, 4(3) 2010, 203-223. Lipp, R. The innovator pipeline: Bioavailability chal- lenges and advanced oral drug delivery opportunities." American Pharmaceuital Review. 16(3) 2013, 10-16. Patil, J.S., Kadam D.V., Marapur S.C., and Kamalapur M.V., Inclusion complex system: A novel technique to improve the solubility and bioavailability of poorly solu- ble drugs: A review. International Journal of Pharmaceutical Sciences Review and Research, 2(2) 2010, 31-34. Siew, A. and Van Arnum, P. Industry perspectives: Achieving solutions for the challenge of poorly water-sol- uble drugs. Pharm Tech (37)6 2013, 60-66. Singh, R. et al. Characterization of cyclodextrin inclu- sion complexes—A review. Journal of Pharmaceutical Science and Technology, 2(3) 2010, 171-183. Singh, S., Baghel, R.S., and Yadav, L. A review on solid dispersion. International Journal of Pharmacy and Life Sciences. 2(9) 2011, 1078-1095. Robert J. Timko, R.Ph., Ph.D., is president of RhoTau Pharma Ser- vices, 920 Sassafras Circle, West Chester, PA 19382. Tel. 484 437 2654. Website: www.RhoTauPharma.com. His consulting work focuses on the pharmaceutical and regulatory sciences. He has nearly 40 years of industry experience in developing and manufacturing innovator and generic drug products. 32 July 2016 Tablets & Capsules