Absorption of Apriso (Mesalamine)
Yes, Apriso (mesalamine) is partially absorbed into the bloodstream, with approximately 21-22% of the administered dose being systemically absorbed. 1
Pharmacokinetics of Apriso
- Apriso consists of mesalamine granules in a polymer matrix with an enteric coating that dissolves at pH ≥6.0, targeting drug release to the mid-ileum and colon 2
- The total absorption of mesalamine from delayed-release formulations is approximately 21-22% of the administered dose 1
- Plasma concentrations of mesalamine become detectable after about 2-4 hours and reach maximum levels by 8-12 hours after administration 1
- Mesalamine's pharmacokinetic parameters are highly variable among individuals 1
Absorption Characteristics by Gastrointestinal Region
- Apriso shows minimal mesalamine levels in the stomach, low to medium levels in the duodenum and proximal jejunum (from 4-7 hours), and high levels in the distal jejunum (from 3-7 hours) 3
- The pH-dependent polymer coating breaks down at or above pH 6.8, normally in the terminal ileum where mesalamine begins to be released from the tablet core 1
- Food intake increases systemic exposure of mesalamine (mean Cmax increased by 91%; mean AUC increased by 16%) compared to the fasted state 1
Metabolism and Elimination
- Mesalamine that is absorbed is metabolized to its primary metabolite acetyl-5-mesalamine 3
- Approximately 43% of mesalamine is bound to plasma proteins 1
- Unabsorbed mesalamine continues through the gastrointestinal tract and is excreted in the feces 3
Clinical Implications
- The limited systemic absorption of Apriso is by design, as mesalamine is intended to work locally in the colon to reduce inflammation in ulcerative colitis 4
- This targeted delivery system helps maximize the therapeutic effect at the site of inflammation while minimizing systemic side effects 2
- Monitoring of renal function is recommended during mesalamine therapy due to potential renal effects from the absorbed portion 5
Comparison to Other Mesalamine Formulations
- Different mesalamine formulations have varying release profiles and absorption characteristics 3
- Pentasa shows higher levels of mesalamine in solution throughout the GI tract from stomach to distal jejunum 3
- Lialda shows minimal mesalamine levels in the stomach and early small intestine 3
Understanding the partial absorption of Apriso is important for monitoring potential systemic effects while recognizing that its primary therapeutic action occurs locally in the colon.