Bioavailability of two selegiline hydrochloride tablet products

Area of Science:

• Pharmacokinetics
• Drug bioavailability
• Clinical pharmacology

Background:

• Selegiline hydrochloride (CAS 14611-52-0) is a medication used in treating Parkinson's disease.
• Assessing the bioavailability of generic drug formulations is crucial for ensuring therapeutic equivalence.

Purpose of the Study:

• To compare the bioavailability of a test selegiline HCl tablet formulation against a reference product.
• To determine the bioequivalence of the two selegiline HCl preparations.

Main Methods:

• A single-blind, randomized, two-way crossover study was conducted in 25 healthy volunteers.
• Participants received single doses of both test and reference selegiline HCl (4 x 5 mg tablets) separated by a 6-14 day washout period.
• Key pharmacokinetic parameters, including Cmax and AUC(0-infinity) of metabolites desmethylselegiline and methamphetamine, were analyzed.

Main Results:

• For desmethylselegiline, the test/reference mean ratio for Cmax was 98.4% (91.2%-106%) and for AUC(0-infinity) was 103% (97.6%-109%).
• For methamphetamine, the test/reference mean ratio for Cmax was 101% (96.8%-105%) and for AUC(0-infinity) was 102% (95.3%-109%).
• Confidence intervals for all key parameters fell within the accepted bioequivalence range (80%-125%).

Conclusions:

• The test selegiline HCl tablet preparation is bioequivalent to the reference preparation.
• Both the rate and extent of formation of key metabolites, desmethylselegiline and methamphetamine, are comparable between the two products.