Pharmaceutical Benefits Scheme
Certain medications listed on the PBS are available only for specific therapeutic indications or to patients meeting specific criteria where the PBAC has deemed that the cost-benefit analysis is favourable only in those indications/patients. These are noted as "restricted benefits" on the Schedule. Medicare Australia places the onus of policing restricted benefits on the prescribers themselves and the pharmacists dispensing (unless the listing is also 'Authority Required'). For example, the COX-2 inhibitor celecoxib is listed on the PBS as a restricted benefit for the symptomatic treatment of osteoarthritis and rheumatoid arthritis. Prescribers using celecoxib for other indications are expected to indicate "non-PBS" on the prescription, and/or the pharmacist dispensing the celecoxib should charge the patient the full cost.
Proxalutamide
Proxalutamide (developmental code name GT-0918) is a nonsteroidal antiandrogen (NSAA) – specifically, a selective high-affinity silent antagonist of the androgen receptor (AR) – which is under development by Suzhou Kintor Pharmaceuticals for the treatment of prostate cancer. It inhibits AR-mediated gene transcription more potently than bicalutamide (by ~5- to 10-fold) and enzalutamide (by 2- to 5-fold) and maintains silent antagonism in castration-resistant prostate cancer (CRPC) cells. It has also been found to downregulate the AR, which could further confer it greater efficacy against CRPC compared to existing NSAAs. Unlike enzalutamide, the drug showed low central nervous system distribution and no induction of seizures in animals. As of 2017, it is in phase II clinical trials for prostate cancer. It is also in preclinical investigation for the treatment of AR-positive breast cancer.