Description:
Doryx Tablets contain doxycycline hyclate pellets coated with a pH dependent polymer; the coated pellets are blended with excipients and compressed into tablets. Two studies were conducted to characterize doxycycline bioavailability following single-dose, oral administration of a Doryx Delayed-Release Tablet sprinkled over applesauce versus a Doryx Delayed-Release Tablet in healthy volunteers. Two single-center, randomized, balanced, single-dose, 2-treatment, 2-period, 2-sequence crossover studies were conducted in healthy male volunteers under medical supervision. In both studies subjects received a single Doryx Delayed-Release Tablet in each of two treatment periods. In Study #1, the tablet was administered intact (Reference) or sprinkled over a spoonful (15 mL) of applesauce (Test); both treatments were administered with 240 mL of water. In Study #2, water was not administered with the Test treatment. Serial blood samples were collected for 96 hours following dose administration. Plasma doxycycline concentrations were determined by a validated HPLC/UV method. The washout period between treatments was 14 or 21 days. Twenty-five subjects completed Study #1, and 24 subjects completed Study #2; the pharmacokinetic data from all subjects was evaluable. All treatments were generally well tolerated.
Following administration of Doryx Tablets either swallowed whole or sprinkled on applesauce plasma doxycycline concentrations increased rapidly (median tmax = 2.0-2.5 hours for all treatments). Doxycycline concentrations then decreased in a log-linear fashion over the remainder of the 96-hour period.
The pharmacokinetic results from the two studies were comparable. The geometric mean doxycycline Cmax values following administration of one Doryx Tablet sprinkled into applesauce was slightly higher than when one tablet was administered whole. For both studies the 90% confidence intervals about the ratio of the Test geometric means to the Reference geometric means were within the 80.00% and 125.00% bioequivalence limits for AUCinf.
Doryx (Doxycycline Hyclate) Delayed-Release tablets, 100 mg either swallowed whole or sprinkled on a spoonful of applesauce were generally well tolerated. When Doryx Tablets are sprinkled over applesauce and taken with or without water, extent of doxycycline absorption is equivalent, but absorption rate is increased slightly. |