Comparative bioavailability study of two haloperidol decanoate containing products

Area of Science:

• Pharmacology
• Pharmaceutics
• Clinical Pharmacy

Background:

• A hospital pharmacy prepared an injectable haloperidol decanoate formulation.
• The formulation contained haloperidol decanoate 141 mg/ml (equivalent to haloperidol 100 mg/ml) in sesame oil.

Purpose of the Study:

• To establish the bioequivalence of the hospital-prepared haloperidol decanoate injection compared to the reference product, Haldol Decanoas.
• To assess the pharmacokinetic profile of the test formulation in schizophrenic patients.

Main Methods:

• An open, randomized, cross-over study involving 15 schizophrenic patients stabilized on Haldol Decanoas.
• Patients received intramuscular injections every three weeks at doses of 100 mg, 200 mg, and 300 mg.
• Concentration-time profiles of haloperidol were established after the fourth injection of both the test and reference products, with pharmacokinetic parameters AUC0-21 and Cmax evaluated.

Main Results:

• The pharmacokinetic parameters AUC0-21 and Cmax were statistically analyzed.
• The study demonstrated that the hospital-prepared haloperidol decanoate injection is bioequivalent to Haldol Decanoas.

Conclusions:

• The hospital-prepared injectable haloperidol decanoate solution is bioequivalent to the reference product.
• This in-house preparation results in substantial annual cost savings of approximately $39,000 for the hospital pharmacy.