New medicine added for pharmacist substitution due to serious shortages
Pharmacists are now able to substitute isosorbide mononitrate 60 mg modified release tablets for isosorbide mononitrate 120 mg modified release tablets without prior approval from the prescriber under the TGA’s new Serious Scarcity Substitution Instrument (SSSI), “so long as the permitted circumstances provided within the SSSI are met”.
Shortages of Imdur Durules and Monodur Durules isosorbide mononitrate 120 mg modified release tablets, used for treatment of angina pectoris, are expected to continue until 19 December 2022, according to the TGA.
The TGA’s SSSI requires that the amount of isosorbide mononitrate 60 mg dispensed results in the patient receiving an equivalent dosage regimen and duration to their prescription for isosorbide mononitrate 120 mg.
Under the legislation, the pharmacist must have advised the patient, or the person acting on behalf of the patient, that two tablets of substitutable medicine are equivalent to one tablet of scarce medicine.
The patient must have a valid prescription for the scarce medicine and the prescriber must not have indicated on the prescription for the scarce medicine that substitution is not permitted.
Pharmacists must also have a process in place to inform the prescriber of the substitution as soon as possible after dispensing the medicine.
The SSSI for Imdur Durules and Monodur Durules tablets is in force from 18 September 2021 until 19 December 2022, however it may be revoked before its end date if the serious scarcity is resolved, or safety concerns are identified.
“Use your professional and clinical judgement to determine whether a patient is suitable for substitution and ensure the patient is fully informed and consents to the change,” said the TGA.
“You must refer patients back to their prescriber if substitution is not appropriate or where alternative treatments may be more appropriate.”
PBS subsidy arrangements for medicines subject to a SSSI have been in place as of 20 August. PBS subsidy will be determined by the Minister for Health for each SSSI that is issued by the TGA.
Only consumers eligible to receive benefits under the PBS will receive subsidised substitute medicines under these arrangements.
Medicines currently covered under these arrangements include tocilizumab 162 mg/0.9 mL injection, 4 x 0.9 mL pen devices; tocilizumab 162 mg/0.9 mL injection, 4 x 0.9 mL syringes; and estradiol 2 mg tablet.
Supply must be in accordance with the SSSI for each medicine.
For example, the TGA’s SSSI requires that the amount of Zumenon (estradiol) 2 mg dispensed results in the patient receiving an equivalent dosage regimen and duration to their prescription for Progynova (estradiol valerate) 1 mg.