Clozapine was first introduced as Clozaril, a brand name of the pharmaceutical company Novartis. However, clozapine is now also available as a generic drug from multiple manufacturers and markets under several generic names worldwide. This can lead to confusion around the identity and interchangeability of products for prescribers, pharmacists, and patients.
United States
In the US, clozapine is available under two generic names – clozapine and clozaril. Both refer to the same compound and are considered interchangeable, however there may be variation between manufacturers in inactive ingredients, dosage forms (tablet, orally disintegrating tablet), and product packaging. The lowest cost generic should be dispensed where possible.
Canada
In Canada, clozapine is sold under three generic names – clozapine, clozaril, and fazaclo. Again, these all refer to the same clozapine compound. Dosage forms, quality, and bioequivalence standards are regulated to be consistent between brands. Cost may vary and guide product selection.
UK and Europe
In the UK, Europe and other markets, clozapine is marketed under additional generic names including clopine, clorilex, denzapine, dozic and zaprine. These are all considered interchangeable forms of clozapine that meet relevant standards around dosage, quality and bioequivalence. The generic name used depends on the specific manufacturer and where it is marketed. Selection is often based primarily on cost and availability.
Australia and New Zealand
The generic names clozapine and clozaril also apply to products marketed in Australia and New Zealand. Additional names include Ciapil, Clopine, and Zaprine. These are all bioequivalent clozapine products from different manufacturers, however only a limited range may be subsidized under national formularies at any given time based on pricing agreements. The longest standing subsidized versions are usually clozapine and clozaril.
In summary, clozapine is marketed under several different generic names internationally, including clozapine, clozaril, fazaclo,zaprine, denzapine, and clopine. While these products are considered interchangeable, there may be variability in cost, dosage forms, package inserts and inactive ingredients between different generic versions and manufacturers. Where multiple options exist, the choice of product is usually based on controlling costs and ensuring consistent supply. However, close monitoring is still required with any change in brand or manufacturer of clozapine due to potential variability in effects between products. Patients should be maintained on a consistent brand where possible for safety and stability of treatment.