The objective of the present study was to develop a colon targeted system of
meloxicam for potential application in the prophylaxis of
colorectal cancer. Efficacy of selective
cyclooxygenase-2 inhibitors has been proven in
colorectal cancer.
Meloxicam is a selective
cyclooxygenase-2 inhibitor with pH-dependent solubility. To achieve pH-independent drug release of
meloxicam, pH modifying agents (buffering agents) were used.
Meloxicam tablets containing
polyethylene oxide were dually coated with
ethyl cellulose containing hydrophilic material,
polyethylene glycol as an inner coating layer and
methyl acrylate, methyl
methacrylate, and
methacrylic acid copolymer (Eudragit® FS 30D) as outer coating layer for colon targeting. Optimized
tablet formulations demonstrated good potential to deliver the
drug to the colon by successfully exhibiting a lag time of 5 h during in vitro drug release study. An in vivo evaluation study conducted to ascertain pharmacokinetic parameters in rabbits revealed that the onset of
drug absorption from the coated
tablets (T(lag time) = 4.67 ± 0.58 h) was significantly delayed compared to that from the uncoated
tablets. The AUC(0→)(t) and AUC(0→∞) for coated
tablets were lower than of uncoated
tablets, although the difference was not significant (p > 0.01). The roentgenography study revealed that the
tablet remained intact, until it reached the colon (5 h), which demonstrates that the system can efficiently deliver the
drug to the colon. This study demonstrated that a
meloxicam-loaded colon targeted system exhibited promising targeting and hence may be used for prophylaxis of
colorectal cancer.