Cost-Effectiveness of Reclassifying Triptans in Australia: Application of an Economic Evaluation Approach to Regulatory Decisions.

BACKGROUND: Migraine is a common, chronic, disabling headache disorder. Triptans, used as an acute treatment for migraine, are available via prescription in Australia. An Australian Therapeutic Goods Administration (TGA) committee rejected reclassifying sumatriptan and zolmitriptan from prescription medicine to pharmacist-only between 2005 and 2009, largely on the basis of concerns about patient risk. Nevertheless, pharmacist-only triptans may reduce migraine duration and free up healthcare resources. OBJECTIVES: To estimate the cost-effectiveness of reclassifying triptans from prescription-only to pharmacist-only in Australia. METHODS: The study design included decision-analytic modeling combining data from various sources. Behavior before and after reclassification was estimated using medical practitioner and patient surveys and also administrative data. Health outcomes included migraine frequency and duration as well as adverse events (AEs) discussed by the TGA committee. Efficacy and AEs were estimated using randomized controlled trials and observational studies. RESULTS: Reclassifying triptans will reduce migraine duration but increase AEs. This will result in 337 quality-adjusted life-years gained at an increased cost of A$5.9 million over 10 years for all Australian adults older than 15 years (19.6 million). The incremental cost-effectiveness ratio was estimated to be A$17 412/quality-adjusted life-year gained. CONCLUSIONS: The incremental cost-effectiveness ratio is likely to be considered cost-effective by Australian decision makers. Serotonin syndrome, a key concern of the TGA committee, had little impact on the results. Further research is needed regarding pharmacist-only triptan use by migraineurs currently using over-the-counter medicines and by nonmigraineurs, the efficacy of triptans, and the risk of cardiovascular and cerebrovascular AEs and chronic headaches with triptans.

Linezolid, the first oxazolidinone antibacterial agent.

Linezolid (Zyvox) is the first member of an entirely new class of antibiotics to reach the market in over 35 years; it was approved for use in 2000. A member of the oxazolidinone class of antibiotics, linezolid is highly effective for the treatment of serious Gram-positive infections and has activity that compares favorably with vancomycin for most clinically relevant pathogens. Zyvox is approved for use against serious Gram-positive infections, including those caused by Streptococcus pneumoniae, and the very challenging methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecium organisms. Zyvox inhibits bacterial protein synthesis by binding to 23S rRNA in the catalytic site of the 50S ribosome. It can be administered both orally and intravenously and has good tissue distribution. Recent results have demonstrated that oxazolidinone analogs related to linezolid are effective in treating pulmonary tuberculosis caused by resistant Mycobacterium tuberculosis in animal infection models and suggest additional new therapeutic applications for these antibiotics.

Recent developments in the identification of novel oxazolidinone antibacterial agents.

The oxazolidinones are a promising new class of synthetic antibacterial agents. Here, we review recent efforts directed at the discovery of new antibacterial compounds of this class. New structures and structure-activity relationships (SAR) are discussed in the context of earlier work in the field. Key issues of potency, spectrum, selectivity, in vivo efficacy, and pharmacokinetic profile of the new analogs are addressed.

Oxazolidinones: a new class of antibacterials.

The oxazolidinones represent the first truly new class of antibacterial agents to reach the marketplace in several decades. They have a unique mechanism of action involving inhibition of the initiation step of protein synthesis and are not cross-resistant to other classes of antibiotics. The first marketed member of that class, linezolid (Zyvox), shows good efficacy with an impressive antibacterial spectrum (including activity against gram-positive organisms resistant to other drugs), and a pharmacodynamic/pharmacokinetic relationship best characterized by time above the minimum inhibitory concentration. The agent is effective by both the intravenous and oral route of administration. Although technically classified as bacteriostatic against a number of pathogens in vitro, linezolid behaves in vivo like a bactericidal antibiotic.