Biological drug use: US perspectives on indications and monitoring

An estimated 20% of patients with rheumatoid arthritis (RA) receive tumour necrosis factor (TNF) inhibitor treatment. This paper presents the results of an online survey of US rheumatologists (1023 respondents) conducted in April 2005 on issues relating to use of TNF inhibitors in RA. The primary determinant of TNF inhibitor use among the participating rheumatologists was physician preference rather than patient preference or payor guidelines. Qualitative (rather than quantitative measures) assessments (physician overall assessment, symptom review, etc.) and laboratory measures were more frequently employed when assessing and treating patients with RA. Clinical assessments with hepatic enzymes and complete blood count as an additional safety tool were most commonly employed to monitor drug safety. Nearly all the rheumatologists (≥92%) felt that a partial purified derivative (PPD) test was indicated when using a TNF inhibitor, but were equally split with regard to those with a history of PPD positivity or BCG vaccination. The frequency of serious adverse events was estimated and included tuberculosis, systemic fungal infection, demyelinating disorders, cytopenia, drug induced lupus, lymphoma, and hepatic failure. Among 454 RA patients who became pregnant while receiving biological therapy there were 378 normal deliveries, 9 premature babies, 5 therapeutic abortions, and 25 miscarriages. It was concluded that a greater than expected number of US rheumatologists are familiar with biologicals and TNF inhibitor therapies, but uncertainties and educational gaps still exist regarding their use and monitoring.