Conclusion

The authors conclude that HS can be applied for the development of sustained-release tablets. Experimental data confirmed the following points:

• Drug release from HS matrix tablets was well controlled under conditions of high ionic strength and high mechanical force
• The zero-order drug-release profile can be obtained by using a mixture of HS and PEG and is independent from drug solubility
• The HS matrix tablets show stable drug-release profiles even under accelerated conditions
• HS is a new matrix excipient that can control drug-release profiles from first- to zero-order sustained release and enables drug release independent of drug solubility and external conditions.

Masaaki Endo is an engineer, Kazuhiro Obae* is a chief engineer, and Yoshihito Yaginuma is a general manager, all in the Ceolus Research and Development Department at Asahi Kasei Chemicals Corporation, 1-105 Kanda Jinbocho, Chiyoda-ku, Tokyo 101-8101 Japan, obae.kb@om.asahi-kasei.co.jp

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