New concepts of clinical trials in rheumatoid arthritis: a boom of noninferiority trials

Influence of active versus placebo control on treatment responses in randomised controlled trials in rheumatoid arthritis

OBJECTIVES

To investigate whether treatment effects of pharmaceutical compounds compared with placebo controls are systematically different to the effects of the same compounds compared with active treatment controls in rheumatoid arthritis (RA) clinical trials.

METHODS

We systematically identified randomised controlled trials (RCTs) in RA, and matched active treatment arms with comparable regimens, populations, background therapy, and outcome reporting, by the nature of their control group (active comparator or placebo). Medline, EMBASE and CENTRAL were used to identify RCTs investigating disease modifying anti-rheumatic drug therapies until December 2021. Using mixed-model logistic regression we estimated OddsRatios (OR) for achieving an American College of Rheumatology (ACR) 20/50/70% response at weeks 12 and 24. Risk of bias was assessed using the Cochrane Tool.

RESULTS

We screened 8328 studies and included 40 for analysis after detailed review of 590 manuscripts; unique compounds had significantly higher responses in active comparator trials compared with their effects observed in placebo controlled trials, with ORs of 1.67 (95% CI 1.46 to 1.91; p<0.001) for ACR20, 1.50 (95% CI 1.29 to 1.75; p<0.001) for ACR50 and 1.65 (95% CI 1.30 to 2.10; p<0.001) for ACR70 (week 12); corresponding ORs for ACR 20, 50, and 70 (week 24) were 1.93 (95% CI 1.50 to 2.48; p<0.001), 1.75 (95% CI 1.32 to 2.33; p<0.001) and 1.68 (95% CI 1.21 to 2.34; p<0.001), respectively. Sensitivity analyses showed consistent results.

CONCLUSION

Placebo controlled trials lead to smaller effect sizes of active compounds in RCTs compared with the same compound in head-to-head trials. This difference may be explained by potential nocebo effects in placebo-controlled settings and needs to be considered when interpreting head-to-head and placebo-controlled trials, by patients, investigators, sponsors and regulatory agencies.

Methotrexate plus ustekinumab versus ustekinumab monotherapy in patients with active psoriatic arthritis (MUST): a randomised, multicentre, placebo-controlled, phase 3b, non-inferiority trial

BACKGROUND

The role of methotrexate in combination with biological agents in patients with psoriatic arthritis remains unclear. The MUST phase 3b trial aimed to compare the efficacy of ustekinumab plus placebo with ustekinumab plus methotrexate in patients with active psoriatic arthritis.

METHODS

In this investigator-initiated, randomised, multicentre, placebo-controlled, phase 3b non-inferiority trial done in 22 centres in Germany, patients with active psoriatic arthritis received open-label ustekinumab and were randomly assigned (1:1) to masked concomitant therapy with placebo or methotrexate (ongoing or new). The primary outcome was non-inferiority of mean Disease Activity Score-28 joints (DAS28) at week 24 for ustekinumab monotherapy (ustekinumab plus placebo) versus ustekinumab combination therapy (ustekinumab plus methotrexate), stratified by previous methotrexate treatment. The key secondary analysis was non-inferiority of DAS28 at week 52. The primary analysis was based on a stratified van Elteren test with an α of 2·5% and a non-inferiority margin of 12·5% by Mann-Whitney estimator. Adverse events and serious adverse events were assessed. This study is registered with ClinicalTrials.gov, NCT03148860.

FINDINGS

Between Jan 24, 2017, and April 12, 2021, 186 patients with active psoriatic arthritis were screened, of whom 173 (93%) patients were enrolled and randomly assigned (1:1) to receive concomitant methotrexate therapy (n=88) or placebo (n=85). 84 patients were receiving methotrexate at baseline, and 89 patients had no previous methotrexate treatment. 166 (96%) patients (87 in the ustekinumab plus methotrexate group and 79 in the ustekinumab plus placebo group) were included in the safety and efficacy analyses at week 24 (69 [42%] female; 97 [58%] male; mean age 48·2 years [SE 1·1]). Ustekinumab plus placebo was non-inferior to ustekinumab plus methotrexate in DAS28 at week 24 (2·9 [SD 1·31] vs 3·1 [1·42]); the stratified Mann-Whitney estimator for treatment comparison was 0·5426 (95% CI 0·4545-0·6307). Non-inferiority for ustekinumab plus placebo was also observed in DAS28 at week 52. Serious adverse events occurred in seven (9%) patients in the ustekinumab plus placebo group and eight (9%) patients in the ustekinumab plus methotrexate group. No specific serious adverse events affected more than one patient, and there were no deaths.

INTERPRETATION

Interleukin (IL)-12 and IL-23 inhibition with ustekinumab is an effective treatment for psoriatic arthritis independent of methotrexate use; concomitant methotrexate did not increase efficacy of ustekinumab (based on DAS28). On the basis of these data, there is no evidence to support the addition or maintainance of methotrexate when initiating ustekinumab in patients with active psoriatic arthritis.

FUNDING

Janssen Cilag.

bDMARD Dose Reduction in Rheumatoid Arthritis: A Narrative Review with Systematic Literature Search

Introduction

Although bDMARDs are effective in the treatment of RA, they are associated with dose-dependent side effects, patient burden, and high costs. Recently, many studies have investigated the possibility of discontinuing or tapering bDMARDs when patients have reached their treatment goal. The aim of this review is to provide a narrative overview of the existing evidence on bDMARD dose reduction and to provide answers to specific dose-reduction-related questions that are of interest to clinicians.

Methods

We systematically searched for relevant studies in four scientific databases. Furthermore, we screened the references of reviews and relevant studies.

Results

Our searches resulted in 45 original studies of bDMARD dose reduction in RA patients (15 RCTs and 30 observational studies). Current evidence shows that bDMARD dose reduction can be considered in all RA patients who achieve stable (e.g., ≥6 months) low disease activity or remission. The best strategies seem to be disease-activity-guided dose optimization and fixed dose reduction, since direct bDMARD discontinuation (without restarting) results in a high flare rate, worse physical functioning, and more joint damage. When tapering the bDMARD treatment of a patient, disease activity should be monitored closely, and if a flare occurs, the dose should be increased to the lowest effective dose. Current evidence shows that restarting bDMARD treatment is effective and safe. Unfortunately, no clear predictors of successful dose reduction have been identified so far.

Conclusion

The current evidence and rising healthcare costs urge that dose reduction should be considered for eligible patients. However, the decision to start dose reduction should be made in shared decision-making. Future research should focus not only on a better understanding of the effects of dose reduction on clinical outcomes but also on the perspectives of patients and physicians as well as the implementation of this new treatment principle.

Electronic supplementary material

The online version of this article (doi:10.1007/s40744-017-0055-5) contains supplementary material, which is available to authorized users.

The -174G/C Interleukin-6 Gene Promoter Polymorphism as a Genetic Marker of Differences in Therapeutic Response to Methotrexate and Leflunomide in Rheumatoid Arthritis

Objective. To evaluate the association of -174G/C IL-6 polymorphism with failure in therapeutic response to methotrexate (MTX) or leflunomide (LEF). This prospective, observational cohort included 96 Mexican-Mestizo patients with moderate or severe rheumatoid arthritis (RA), initiating MTX or LEF, genotyped for IL-6 -174G/C polymorphism by PCR-RFLP. Therapeutic response was strictly defined: only if patients achieved remission or low disease activity (DAS-28 < 3.2). Results. Patients with MTX or LEF had significant decrement in DAS-28 (p < 0.001); nevertheless, only 14% and 12.5% achieved DAS-28 < 3.2 at 3 and 6 months. After 6 months with any of these drugs the -174G/G genotype carriers (56%) had higher risk of therapeutic failure compared with GC (RR: 1.19, 95% CI: 1.07-1.56). By analyzing each drug separately, after 6 months with LEF, GG genotype confers higher risk of therapeutic failure than GC (RR = 1.56; 95% CI = 1.05-2.3; p = 0.003), or CC (RR = 1.83; 95% CI = 1.07-3.14; p = 0.001). This risk was also observed in the dominant model (RR = 1.33; 95% CI = 1.03-1.72; p = 0.02). Instead, in patients receiving MTX no genotype was predictor of therapeutic failure. We concluded that IL-6 -174G/G genotype confers higher risk of failure in therapeutic response to LEF in Mexicans and if confirmed in other populations this can be used as promissory genetic marker to differentiate risk of therapeutic failure to LEF.