Patterns of use for biologics in rheumatoid arthritis are complex, according to Australian research presented at the 2019 ACR/ARP Annual Meeting in Atlanta.

According to an analysis of 3,470 participants in ARAD (Australian Rheumatology Association Database) from 2001 to 2018, first-line bDMARDS were largely etanercept (ETA, n=1,414) and adalimumab (ADA, n=1,024), followed by infliximab (INX, n=155), golimumab (n=98), abatacept (ABA, n=66), certolizumab (n=38), tocilizumab (TOC, n=21), rituximab (n=24) and tofacitinib (TOF, n=23).

The median time on first-line bDMARD varied from 258 days for ABA to 98 days for TOF, according to the data presented by Professor Marissa Lassere of  the Department of Rheumatology, St George Hospital, Sydney.

Almost half the patients (47.7%) who started first-line bDMARD therapy switched to another bDMARD, while a similar proportion (50.5%) switched from second-line therapies and 42.3% switched from third-line therapies.

“Compared with first-line ETA, participants were more likely to stop first-line ADA (HR 1.16; 95%CI: 1.04-1.29) and INX (HR 1.52; 95%CI: 1.26-1.85), whereas no differences were seen for other first-line bDMARDs,” the study authors said.

“For second-line therapies, compared to ETA, the risk of stopping was higher for INX and lower for TOC and TOF. For third-line, the risk of stopping was lower for all bDMARDs except INX.”

The analysis found lack of treatment efficacy (52.8%) then side effects (20.6%) were the most commonly cited reason for stopping therapy, irrespective of the line of treatment.

Factors associated with switching biologics compared to continuing first-line use were female gender, tertiary education, more recent questionnaire year, higher HAQ score, current prednisolone and current opioid use.

Switching due to side effects was more strongly associated with a higher HAQ score and longer duration of disease compared to switching due to inefficacy.