8MAY - 2022TECH OUTLOOKIN MY OPINIONPharmaceutical Tablet Coating ­ Past, Present and FutureBy Steve Brown, Senior Director EU and APAC Global Manufacturing Science and Technology, Teva Pharmaceuticals [NYSE:TEVA]Pharmaceutical tablet coating was initially developed from the confectionary industry and transferred to the pharmaceutical industry to produce sugar coated tablets.These tablets are elegant and easy to swallow with the taste and odour of the active ingredient masked. This process was very effective but required long process times of upto 5 days and highly skilled operators. In the 1950s and 60s compression coating, also known as a tablet in a tablet,was developed as a replacement to sugar coating but due to complex tabletting machines and slow compression speeds this technology did not take off. In parallel, the advancement in soluble cellulosic polymers and the development of Pellegrini and side-vented coating pans soon became the standard for modern tablet film coating technology and replaced the traditional sugar coating process.The first commercially available film-coated tablet was developed and introduced by Abbott Laboratories in 1954. This was produced from ahydroxyl propyl methyl cellulose polymer dissolved in organic solvent and sprayed onto the tablets using a Wurster fluid bed process. The principle of spraying a coating solution or suspension onto a tablet which is then rapidly dried and repeated until the desired coating appearance or functionality has been achieved is still the same now as it was in 1954. The processing equipment evolved from the Wurster fluid bed process to the side vented coating pan, which is significantly more efficient.The cellulosic polymers also advanced to be aqueous soluble removing the requirement for solvent handling systems. The science of film coating and the knowledge developed to understand this process has evolved and is now a well understood technology.Steve Brown
< Page 7 | Page 9 >