Per-oral tacrolimus administration is not always practicable.
Sublingual administration is a potential alternative, but its feasibility and effectiveness compared with oral route has not been established.
Dr Benitez and colleagues compared tacrolimus drug exposure after sublingual and oral administration in liver transplant recipients.
The research team performed an experimental, open-label, non-randomized, cross-over study.
Tacrolimus exposure was evaluated in 32 liver transplant recipients receiving oral administration.
The team calculated 12 hour tacrolimus area-under-the-curve using tacrolimus blood concentrations at 0-0.5-1-2-4-6-8-12 hours post-dose.
Recipients were switched to sublingual administration, and dose was adjusted to reach similar trough levels.
|Daily dose of tacrolimus required in sublingual phase was 37% lower than that used in oral phase|
|Alimentary Pharmacology & Therapeutics|
The researchers found that similar trough levels were accomplished with oral and sublingual administration.
Although concentration 2 hours post dose was higher in oral phase.
The team observed that daily dose of tacrolimus required in sublingual phase was 37% lower than that used in oral phase, suggesting significantly increased bioavailability of tacrolimus when employing sublingual route.
Good correlation between area-under-the-curve, and trough levels was observed in sublingual phase.
The research team noted that 22 recipients were maintained on sublingual administration after the end of study.
The researchers observed no difference in liver function tests or rejection rates during follow-up period.
Dr Benitez's team concludes, "Sublingual administration of tacrolimus is feasible and provides similar drug exposure compared with oral administration."
"In our study, at long-term follow-up, sublingual administration was not associated with liver transplant rejection."