Purpose: Gastroretentive (GR) systems are designed to prolong gastric residence time, thereby achieving sustained absorption and improved oral bioavailability for drugs with a narrow absorption window in the upper part of the gastrointestinal tract. The present study aimed to develop a novel GR system for acyclovir by using 3D printing technologies.
Methods: The GR system consists of a novel gastro-floating device that can be buoyant in the gastric fluid and a conventional sustained release (SR) acyclovir tablet that is inserted inside of the gastro-floating device to allow sustained release of the drug in the stomach. The oblong-shaped gastro-floating device that has inner compartments of air pockets and the inner tablet was designed and printed with polylactic acid filament using a fused deposition modeling (FDM) printer. The in vitro buoyancy and dissolution were determined by the paddle method. The in vivo pharmacokinetic study was performed following oral administration of the novel GR system in Beagle dogs. Concentrations of acyclovir in the dissolution medium and dog plasma were determined by high-performance liquid chromatography (HPLC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis, respectively.
Results: In the in vitro dissolution test, the GR system was buoyant for more than 24 h and sustained release characteristics were identified with the average time to reach 80% dissolution (T80) being 3.59 h. Following oral administration, the time to reach the maximum concentration (Tmax) and mean residence time (MRT) of acyclovir were significantly prolonged, while maximum concentration (Cmax) was significantly decreased compared with those obtained after reference tablet administration. The relative bioavailability was 122.67% for GR system compared to the reference immediate release (IR) tablet. The abdominal X-ray images showed that the developed GR system stayed in the stomach more than 12 h.
Conclusion: A novel GR system of acyclovir was developed by combining a 3D printed gastro-floating device with an acyclovir SR tablet. The potential of a novel GR system was demonstrated to reduce dosing frequency and improve the oral bioavailability. The developed GR system can be applied to various drugs and holds great promise to design and develop novel controlled release formulations.
JUNYOUNG LIM– Master's Course, Sungkyunkwan University, Suwon-si
SEUNG EUN CHUNG– Master's Course, Sungkyunkwan university, Suwon-si
DAYOUNG LEE– Sungkyunkwan University
HYEONMYEONG JEONG– Graduate Student, Sungkyunkwan University, Suwon, Kyonggi-do
Soyoung Shin– Wonkwang University
BEOM SOO Shin– Sungkyunkwan University, Kyonggi-do