BECLATE Nasal spray Ref.[50453] Active ingredients: Beclometasone

Absorption

The absolute bioavailability of B-17-MP, following intranasal administration of BDP is 44% and <1% of the dose is absorbed by the nasal mucosa. The remainder cleared from the nose by either mucocilary clearance or drainage, is available for absorption from the gastrointestinal tract. Plasma B-17-MP is almost entirely due to conversion of beclomethasone dipripionate absorbed from the swallowed dose. Absolute bioavailability of the active metabolite (B-17-MP) is 41%, following oral administration of beclomethasone dipripionate.

B-17-MP is absorbed slowly following an oral dose, and peak plasma levels are reached 3-5 hours after dosing.

Metabolism

Following oral or intranasal dosing BDP, is cleared very rapidly from the circulation and plasma concentrations are undetectable (<50 pg/ml). The majority of the swallowed portion of BDP, is metabolized during its first passage through the liver. The main product of metabolism is the active metabolite (B-17-MP). Minor inactive metabolites, beclomethasone-21-monopropionate (B-21-MP) and beclomethasone (BOH), are also formed but these contribute little to systemic exposure.

Distribution

The tissue distribution at steady-state for BDP is moderate but more extensive for B-17-MP. Plasma protein binding of BDP is moderately high (87%).

Elimination

The elimination of BDP and B-17-MP are characterised by high plasma clearance (150 and 120 L/h) with corresponding terminal elimination half-lives of 0,5 h and 2,7 h. Approximately 60% of the dose was excreted in the faeces mainly as free and conjugated polar metabolites, within 96 hours following oral administration of tritiated BDP. Approximately 12% of the dose was excreted as free and conjugated polar metabolites in the urine.