Session Information
Date: Sunday, November 13, 2016
Title: Rheumatoid Arthritis – Small Molecules, Biologics and Gene Therapy - Poster I
Session Type: ACR Poster Session A
Session Time: 9:00AM-11:00AM
Background/Purpose: Although evidence from randomized trials suggest similar efficacy and safety on a group level for the different anti-TNF drugs available for the treatment of RA, and many treatment guidelines rank them as interchangeable in terms of effect, there are few head-to-head comparisons and limited real world data on their comparative effectiveness in clinical practice. Our objective was therefore to perform a head-to-head comparison of the initial effectiveness of different TNF inhibitors among bionaïve patients with RA in a large population-representative sample
Methods: The Swedish Rheumatology Register (SRQ) covers about 95% of all biological treatment of RA, with data on clinical characteristics prospectively recorded at treatment initiation and at subsequent patient visits. We included all patients with RA registered in the SRQ as starting etanercept, infliximab (including originator product and its biosimilar), adalimumab, certolizumab pegol, or golimumab as their first ever biological DMARD (N=6149) between 1st Jan 2010 and 31st July 2015, with follow-up through March 31st2016. Effectiveness was defined as 1) remaining on therapy, 2) being in remission or low disease activity (DAS28<2.6), and 3) having achieved a EULAR response, all at the evaluation visit at 5 (3-8) months after start (defined as the visit closest to 151 days of all visits between 60 and 242 days; this method has previously been shown to capture 95% of patients with follow-up visits within one year of treatment initiation). Differences in crude proportions were tested across drugs using χ2-tests. To take baseline differences in patient characteristics into account, relative risks were estimated using generalized log-binomial regression adjusting for sex, age, concomitant use of DMARDs, Rheumatoid Factor, HAQ, and disease duration.
Results: : Across all anti-TNF drugs, about 90% remained on therapy until the evaluation visit, and most patients remaining on drug also had a positive response, with about 40% having DAS28 below 2.6, and almost half reaching a good EULAR response. As shown in the Table, only the crude proportion with DAS28 below 2.6 was statistically significantly different across treatments (p=0.011), but this difference was no longer significant after taking baseline characteristics, and proportions discontinuing drug, into account. Although some one-on-one comparisons approached borderline significance (e.g. lower proportion discontinuing therapy in adalimumab vs.etanercept, p=0.06), the number of pairwise tests lead to risk of false positives, and the global test showed no significant inter-drug difference.
Conclusion: These results suggest limited differences in effectiveness among available TNF inhibitors for the treatment of RA in current clinical practice, at least regarding the initial response among previously bionaïve patients
Status at evaluation visit at 5 months among all patients with RA initiating TNFi as first ever biologic DMARD 2010-2015 in Sweden | |||||||||
Etanercept |
Infliximab |
Adalimumab |
Certolizumab pegol |
Golimumab |
P-value |
||||
N |
1826 |
1495 |
1087 |
979 |
762 |
||||
Observed percentage | |||||||||
Discontinued |
11.5 |
9.8 |
9.2 |
11.6 |
9.2 |
0.11 |
|||
DAS28 < 2.6* |
42.9 |
35.9 |
42.2 |
39.1 |
41.9 |
0.01 |
|||
EULAR response* | |||||||||
Good |
47.3 |
42.0 |
46.8 |
46.0 |
46.0 |
0.23 |
|||
Moderate |
29.2 |
32.8 |
30.3 |
31.6 |
30.5 |
0.58 |
|||
None |
23.5 |
25.2 |
22.9 |
22.4 |
23.6 |
0.79 |
|||
Adjusted relative risk† | |||||||||
Discontinued |
Ref. |
0.89 (0.71-1.13) |
0.77 (0.59-1.01) |
1.01 (0.80-1.29) |
0.83 (0.62-1.12) |
0.25 |
|||
DAS28 < 2.6‡ |
Ref. |
0.92 (0.81-1.04) |
1.03 (0.91-1.16) |
0.95 (0.83-1.09) |
0.99 (0.85-1.14) |
0.54 |
|||
EULAR response¶ | |||||||||
Good |
Ref. |
0.94 (0.83-1.06) |
1.01 (0.88-1.15) |
1.05 (0.92-1.20) |
1.03 (0.89-1.20) |
0.57 |
|||
Good or Moderate |
Ref. |
0.99 (0.91-1.07) |
1.02 (0.93-1.12) |
1.06 (0.97-1.15) |
1.05 (0.95-1.15) |
0.59 |
|||
None or discontinued |
Ref. |
1.07 (0.93-1.23) |
0.93 (0.80-1.09) |
1.08 (0.93-1.26) |
0.95 (0.80-1.14) |
0.32 |
|||
Notes: P-values from χ2-tests for proportions, and type 3 Wald test in regression model, *) Proportion among those remaining on drug. | |||||||||
†) Adjusted for sex, age, RF, baseline disease duration, HAQ, and concomitant use of MTX, non-MTX DMARD, corticosteroids | |||||||||
‡) Comparing “remission” to “no-remission, or no longer on therapy” | |||||||||
¶) Comparing each response category to “any other response, or no longer on therapy” |
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To cite this abstract in AMA style:
Frisell T, Dehlin M, Di Giuseppe D, Feltelius N, Kastbom A, Turesson C, Askling J. Comparative Effectiveness of Different Anti-TNF Drugs As First Biological DMARD in RA: Results from the Nationwide Swedish Register 2010-2015 [abstract]. Arthritis Rheumatol. 2016; 68 (suppl 10). https://acrabstracts.org/abstract/comparative-effectiveness-of-different-anti-tnf-drugs-as-first-biological-dmard-in-ra-results-from-the-nationwide-swedish-register-2010-2015/. Accessed .« Back to 2016 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/comparative-effectiveness-of-different-anti-tnf-drugs-as-first-biological-dmard-in-ra-results-from-the-nationwide-swedish-register-2010-2015/