The current practice of ‘a’ flagging in the Schedule of Pharmaceutical Benefits denotes that brand substitution may be undertaken by pharmacists at the point of dispensing without differences in clinical effect.

An ‘a’ located immediately before brand names of a particular strength of an item indicates that the sponsors of these brands have submitted evidence of bioequivalence or therapeutic equivalence, or that justification for not needing bioequivalence or therapeutic equivalence has been provided to the TGA.

Note that ‘a’ flagging does not apply to similar biological medicinal products, which are biological products that demonstrate a degree of similarity to an already-approved product, sometimes referred to as ‘biosimilars’.

The equivalence for other brands not indicated under ‘a’ flagging is unknown and may be due to bioequivalence data not being considered necessary when products were registered or advice not being forthcoming from sponsors. This does not necessarily reflect a lack of safety or efficacy, but under these circumstances, caution should be taken when brands are interchanged.

A 'b' attached to the brand names indicates that these brands are also equivalent, but that it is not known if there is equivalence between brands marked 'a' and brands marked 'b'.

Brand equivalence denoted ‘b’ is distinct from the 'B' located immediately before an amount in the premium column, which indicates a brand premium applies to the item (see Figure 1).

Figure 1: Symbols used to indicate aspects of brand equivalence in a PBS listing
Symbols used to indicate aspects of brand equivalence in a PBS listing

A brand premium applies to multi-branded items listed on the PBS that are priced above the lowest priced brand and available for brand substitution. Generic equivalents are clinically equivalent and undergo the same strict quality controls.

This means consumers may have to pay extra for more expensive brands (e.g. those to which a brand premium applies).

Brand substitution by pharmacists is permitted without reference to the prescriber when the patient agrees to substitution and the prescriber has not indicated on the prescription form that substitution should not occur.

Only brands identified in the Schedule of Pharmaceutical Benefits as being interchangeable (i.e. brand equivalent ‘a’ or ‘b’) and permitted under the relevant State or Territory legislation are available for substitution.

If a prescription is written generically or for the lowest priced brand and the lowest priced brand is supplied, no brand premium applies.

If a brand of drug subject to a therapeutic group premium also has a brand premium, there will be two amounts shown on separate lines in the premium column, prefixed by ‘T’ and ‘B’ respectively. The ‘T’ here denotes that a therapeutic group premium applies.

For more information, visit the PBS website