Biological disease-modifying antirheumatic drugs (bDMARDs) for rheumatoid arthritis (RA) treatment were among the first high-cost medicines to be subsidised in Australia. High-cost medicines pose several challenges to the Australian National Medicines Policy, which aims to provide timely access to effective medicines at a cost individuals and the community can afford. Thus, novel restriction criteria were developed to encourage cost-effective use of bDMARDs. Government expenditure on bDMARD subsidies for RA treatment grew to about $383 million in 2014. Evidence that initiation and continuation criteria for bDMARDs meet usually applied cost-benefit criteria is lacking. The combined expenditure on tocilizumab, certolizumab pegol and golimumab (added to the Australian Government's Pharmaceutical Benefits Scheme in 2010) was $93 million in 2014, which is 210% over the initial estimate. Present and future challenges with regard to bDMARDs for RA and other high-cost drugs include improved expenditure predictions, monitoring of cost-effectiveness in relation to actual use and strategic development, regulation and use of biosimilars. Ten years of documentation on clinical and laboratory findings indicating eligibility to initiate and continue on bDMARDs remains un-used. These data represent an untapped opportunity to promote quality of use of bDMARDs and biosimilars and to improve cost predictions for high-cost drugs.