Readers are invited to write in with their questions about decisions of the Pharmaceutical Benefits Advisory Committee (PBAC). Australian Prescriber publishes selected questions from readers, together with answers from the PBAC. Questions may address issues such as regulatory decisions, pharmaceutical benefits listings and withdrawals.
This exclusive arrangement helps Australian Prescriber readers understand how the contents of the Pharmaceutical Benefits Scheme (PBS) are determined.
Letters and responses are reviewed by the Editorial Executive Committee and may be edited before publication. It may not be possible to reply to all individual questions.
Your questions to the PBAC
The listing of celecoxib as a general benefit on the Pharmaceutical Benefits Scheme (PBS) from 1 August 2000 was welcomed by arthritis sufferers Australia-wide. However, the decision to list the 200 mg capsules with an issue quantity of 60 rather than 30 has surprised many pharmacists. This exceeds the 30 day supply rule, taking into account the manufacturer's recommended one capsule a day dosage.
Correction (added June 2001)
This letter mentioned celecoxib as a general benefit on the Pharmaceutical Benefits Scheme (PBS). This is incorrect. Celecoxib is listed on the PBS as a restricted benefit for chronic arthropathies (including osteoarthritis) with an inflammatory component.
A more serious problem is the number of potential adverse sulfonamide-type reactions that may occur around Australia, and the subsequent waste of Commonwealth funds when celecoxib is discontinued by the patients. In our town of 5000 there has been a high demand for celecoxib and within one week of listing we had six adverse sulfonamide-type reactions, with swelling of the throat, body rash and fever. One patient ended up in Moruya Hospital and the rest were referred to their general practitioner.
As a medication review pharmacist, I am concerned about the incidence and severity of these reactions. They usually occur within a few days of commencing celecoxib and the patient has to cease the medication. As celecoxib 200 mg is the most commonly prescribed dose, I believe that the decision by the Pharmaceutical Benefits Advisory Committee to list the 200 mg capsules in a quantity of 60 was a poor one, and will result in a significant waste of PBS funds.
The Pharmaceutical Benefits Advisory Committee (PBAC) recommends the maximum quantity and the number of repeats that should apply to the prescribing of a particular medication. The maximum quantity recommended for listing by the PBAC usually corresponds to the pack size produced by the manufacturer.
For drugs which are intended for use in chronic conditions, the PBAC recommends a maximum quantity and number of repeats which will provide sufficient supply of the drug for six months' therapy at normal dosage levels.
The current dosage of celecoxib for the treatment of osteoarthritis is 200 mg once daily or 100 mg twice daily, with some patients requiring 200 mg twice daily. The dosage for rheumatoid arthritis is 100 mg or 200 mg twice daily. The PBAC therefore recommended a maximum quantity of 60 capsules for both the 100 mg and 200 mg strengths of celecoxib in an attempt to encompass the complete dosage range required by patients. The maximum quantity listed in the Pharmaceutical Benefits Scheme (PBS) Schedule for celecoxib 200 mg provides for one month's therapy at maximum dosage levels and for two months' therapy at minimum dosage levels. The maximum number of repeats (three, for consistency with the listings of the non-steroidal anti-inflammatory drugs) provides for a supply of four months or eight months of medication depending on the patient's dose.
Doctors are under no obligation to prescribe the full maximum quantity specified in the Schedule for a particular drug. They may, at their discretion, prescribe smaller quantities than those listed in the Schedule.
The mechanism via which adverse drug reactions are monitored in Australia is administered by the Adverse Drug Reactions Advisory Committee (ADRAC) of the Therapeutic Goods Administration. Pharmacists who see unexpected reactions can notify the ADRAC Secretariat by filling out the blue report card which is enclosed in every copy of the PBS Schedule.