A closer look at the role of bDMARDs in psoriatic arthritis

Infliximab, etanercept, adalimumab, ixekizumab, ustekinumab, secukinumab, and certolizumab pegol provided improvements in health assessment questionnaire-disability index scores from baseline.

14 randomized clinical studies were evaluated

Infliximab, etanercept, adalimumab, ixekizumab every 2 weeks, ustekinumab, secukinumab 150 mg, and certolizumab pegol provided improvements in health assessment questionnaire-disability index (HAQ-DI) scores from baseline, which were significantly better than placebo in biologic-naïve patients with active psoriatic arthritis (PsA).

Analyses also indicate that changes from baseline in HAQ-DI scores were more pronounced in psoriatic arthritis response criteria (PsARC) responders than in PsARC non-responders for each treatment.

Apart from a decreased quality of life, PsA is also characterized by a substantial economic burden (See 1,2). Biologic treatments for PsA are increasingly scrutinized in health technology assessments, and the most commonly used economic model framework for assessing biologics in PsA is the York Assessment Group model developed as part of a NICE appraisal (the so-called “York model”) (See 3). In this model, improvement in HAQ-DI reflects physical function and is linked to initial treatment response measured by joint improvement assessed by PsARC. Ruyssen-Witrand et al. assessed the effectiveness of biologic disease-modifying antirheumatic drugs (bDMARDs) on HAQ-DI among active biologic-naïve PsA patients through Bayesian network meta-analysis to understand the relationship between HAQ-DI and PsARC response. 

Data were identified through a systematic literature review, and Bayesian network meta-analyses were conducted in line with NICE guidelines to assess the mean HAQ-DI scores change from baseline for ixekizumab, adalimumab, ustekinumab, etanercept, golimumab, infliximab, apremilast, secukinumab, certolizumab pegol, and placebo in the biologic-naïve overall population as well as in PsARC responders and non-responders (See 4). Results were expressed as absolute mean change from baseline and associated standard deviations, and 95% credibility intervals. Treatment effects were estimated based on results at 12 weeks where available; otherwise, data relating to the closest time period after 12 weeks were used (up to 16 weeks). 

A total of fourteen randomised clinical studies were identified for inclusion in the analyses evaluating effects on HAQ-DI scores, which included ixekizumab every 2 weeks (n=1) and every 4 weeks (n=1), etanercept (n=1), infliximab (n=2), ustekinumab (n=1), golimumab (n=1), apremilast (n=3), secukinumab (n=1), and adalimumab (n=3). For apremilast, certolizumab pegol and secukinumab, data were not available specifically from biologic-naïve patients, and data from the full study population (i.e. biologic naïve and biologic experienced) were used. It was shown that in the overall population, all biologic agents apart from ixekizumab every 4 weeks, golimumab and apremilast significantly improved HAQ-DI scores from baseline when compared to placebo. Improvement in the overall population was greatest for ixekizumab every 2 weeks, etanercept, infliximab, certolizumab pegol, and secukinumab. Among PsARC responders, the greatest improvement from baseline in HAQ-DI scores was observed for infliximab, etanercept and ixekizumab every 2 weeks, secukinumab and ixekizumab every 4 weeks (see 5).

Sources 
1. Lee S, et al. The burden of psoriatic arthritis. PT Dec 2010;35(12):680-689.
2. Kawalec P, et al. The indirect costs of psoriatic arthritis: systematic review and meta-analysis. Expert Rev Pharmacoecon Outcomes Res. Feb 2015;15(1):125-132.
3. Woolacott N, et al. Etanercept and infliximab for the treatment of psoriatic arthritis: a systematic review and economic evaluation. Health Technol Assess Sep 2006;10(31):iii-iv, xiii-xvi, 1-239. 
4. Dias S, et al. Nice DSU technical support document 2: A generalized linear modeling framework for pairwise and network meta-analysis of randomized controlled trials.  National Institute for Health and Clinical Excellence 2011. 
5. Ruyssen-Witrand A, et al. Effects of biologic DMARDs on physical function in patients with active psoriatic arthritis: Results of network meta-analyses. Abstract THU0290. EULAR 2018.