Pharmacokinetic assessment and level-A IVIVC establishment of rifampicin-loaded 3D printed tablets using SLS 3D printing

Background This study investigated the in vitro dissolution and in vivo absorption of rifampicin (RIF)-containing 3D-printed tablets using Selective Laser Sintering (SLS) technology.Methods In vitro dissolution was assessed in acidic (pH 1.2) and alkaline (pH 6.8) buffer media, while in vivo absorption was evaluated in a New Zealand White rabbit model. Both analytical and bioanalytical methods were rigorously developed and validated using LC-ESI-MS/MS, following ICH Q2 (R1) and FDA guidelines, respectively.Results In the acidic medium, 16.22% of RIF was released within the first 2 h, whereas in the alkaline medium, the release increased to 41.75%, indicating a sustained release from the sintered 3D printed tablets. Pharmacokinetic parameters and their corresponding values of Cmax (445.38 ± 193.62 ng/mL), Tmax (02 ± 0.00 hr), AUC0-t (841.51 ± 334.13 ng.h/mL), AUC0-∞ (861.66 ± 340.54 ng.h/mL), Kel (0.61 ± 0.13 h−1), and t1/2 (1.18 ± 0.25 hr) were obtained, demonstrating effective RIF absorption in the rabbit. Additionally, an in vitro-in vivo correlation (IVIVC) model was developed, demonstrating a good correlation between in vitro release and in vivo absorption, with R2 value of 0.9696.Conclusion The results underscore the potential of SLS 3DP technology in advancing the development of RIF-containing 3D printed tablets by sustaining in vitro dissolution following in vivo absorption profiles.