改善高吸濕性藥品(pyridostigmine bromide)之長效處方設計及其體內體外相關性之研究

A sustained-release formulation study on the hygroscopic drug (pyridostigmine bromide) and the investigation of in vitro/in vivo correlation characteristics

黃郁婷(Yuh-Tyng Huang)

指導教授 ： 詹道明

高雄醫學大學/藥學院/藥學研究所/博士(2007年)

摘要

本研究選擇一具高吸濕特性之藥品（pyridostigmine bromide；以下簡稱PB）為模式藥。在整個實驗過程，利用擠壓搓圓法、直接壓錠法及流動床包衣法將PB製成長效劑型（長效圓粒錠及長效圓粒）；並利用實驗設計法來篩選最佳處方及探討製備過程中最具有影響之因子。在體外試驗的部份，首先利用Taguchi實驗設計法來篩選以擠壓搓圓方法製備含藥之核心圓粒最佳處方；並探討於製程中最具有影響的因子。進一步再利用23複因子實驗設計法來篩選一組最佳之長效製劑處方進行動物體內體外相關性實驗。我們期許這組最佳處方能於溶離之特定時間點能釋出特定的藥量；並以零階次的模式來釋出藥品。（對於最佳的長效圓粒錠而言，藥品於1小時，6小時及12小時的溶離時間點分別釋出15.84%，58.56% 及93.10%；而對於最佳的長效圓粒來說，藥品於1小時，6小時，12小時及24小時的溶離時間點則分別釋出6.24%，33.48%，75.18% 及95.26%）。由卡式水分測定儀所得之結果得知，本實驗所製備的二組最佳長效製劑處方均有改善PB吸濕特性的缺點。
在體內試驗，由計算所得的藥物動力學數據顯示，本實驗中製備的兩組最佳長效製劑處方所達血中最高濃度之時間（Tmax）比市售速效錠長，且血中時間-濃度曲線下面積也比市售速效錠大，並具有良好的體內-體外相關性。最後，取最佳長效圓粒處方進行動物體內之微透析試驗。經投藥後，由體內乙醯膽鹼及游離藥品（蛋白未結合藥品）之釋出百分率得知，本實驗中自製之長效圓粒處方於體內釋出之速率比市售速效錠及注射劑慢；此種現象就代表自製之長效圓粒處方於體內作用時間比市售速效錠及注射劑長，能達長效持續釋出之作用。
我們期許本實驗自製之長效製劑處方，未來若運用於危險恐怖攻擊或戰爭時能改善一些事後解毒劑之限制，並減少投藥次數及增加藥品於體內作用的時間。

關鍵字

長效圓粒錠 ； 長效圓粒 ； 壓搓圓法 ； 直接壓錠法 ； 流動床包衣法 ； Taguchi實驗設計法 ； 23複因子實驗設計法 ； 零階次模式 ； 吸濕特性 ； 體內-體外相關性 ； 乙醯膽鹼 ； 游離藥品（蛋白未結合藥品） ； 微透析技術

並列摘要

Pyridostigmine bromide (PB), a highly hygroscopic drug was selected as the model drug. The PB sustained-release (SR) dosage forms (SR tableted-pellets and SR pellets) that were developed by extrusion-spheronization, direct compression and fluid-bed methods using Taguchi experimental and 23 full factorial design. Preceding in vitro studies, Taguchi experimental design was used to optimize formulations and process parameters for the extrusion-spheronization process to prepare drug-containing core pellets. Moreover, 23 full factorial design was utilized to search for the optimal PB-SR dosage forms with specific release rate at different time intervals (the released % of 1h, 6h and 12h were 15.84%, 58.56% and 93.10% for SR tableted-pellets and the release % of 2h, 6h, 12h and 24 h were 6.24 %, 33.48 %, 75.18 % and 95.26 % for SR pellets) and follow zero-order mechanism. The results of moisture absorption by Karl Fischer meter shown the optimal PB-SR dosage forms could improve the hygroscopic defect of pure drug (PB).
In the in vivo study, the results of the bioavailability data showed the Tmax and AUC0-t were prolonged and increased for optimal PB-SR dosage forms when compared with commercial immediate release (IR) tablets. Furthermore, a good linear regression relationship was observed between the fraction dissolution and fraction absorption for the optimal PB-SR dosage forms. Finally, the PB-SR pellets were chosen to proceed the microdialysis study. According to the results of microdialysis technique shown that the release of acetylcholine and the release of protein unbound drug for the PB-SR pellets were slower than IV-injection and commercial IR tablets; this phenomenon indicating that the occupancy time of drug efficacy in vivo of PB-SR pellet was longer than the others, that is to say, the PB-SR pellets provided with SR effect in vivo as well.
We believe that PB-SR dosage forms designed in our study would improve limitations of post-exposure antidotes, decrease the frequency of administration and enhance the retention period of drug efficacy in vivo, for personnel exposed to contamination situations in wars or terrorist attacks in the future.

並列關鍵字

Sustained-release tableted-pellets ； Sustained-release pellets ； Extrusion-spheronization method ； Direct-compression method ； Fluid-bed method ； Taguchi experimental design ； 23 full factorial design ； Zero-order mechanism ； Hygroscopic character ； In vitro-In vivo correlation ； Acetylcholine ； Protein unbound drug ； Microdialysis technique

參考文獻

Agrawal, A.M.; Howard M.A.; Neau, S.H. Extruded and spheronized beads containing no microcrystalline cellulose: influences of formulation and process variables. Pharm. Dev. Technol. 2004, 9 (2), 197-217.

Aulton, M.E.; Dyer, A.M.; Khan, K.A. The strength and compaction of millispheres. Drug Dev. Ind. Pharm. 1994, 20 (20), 3069-3104.

Aulton, M.E.; Twitchell, A.M.; Hogan, J.E. Physical properties of HPMC solutions and their role in the film coating process and the quality of the coated product. In Aqueous Polymeric Coatings for Pharmaceutical Dosage Forms; McGinity, J.W., Ed.; Marcel Dekker, Inc.: New York, 1997; 227-266.

Baert, L.; Remon, J.P. Influence of amount of granulation liquid on the drug release rate from pellets made by extrusion spheronisation. Int. J. Pharm. 1993, 95 (1-3), 135-141.

Bashaiwoldu, A.B.; Podczeck, F.; Newton, J.M. A study on the effect of drying techniques on the mechanical properties of pellets and compacted pellets. Eur. J. Pharm. Sci. 2004, 21 (2-3), 119-129.