Investigators found positive results when examining the safety and efficacy of filgotinib in the FINCH 2 phase 3 clinical trial.
Results of the FINCH 2 trial revealed that filgotinib use resulted in a significantly greater proportion of patients with moderate to severe rheumatoid arthritis (RA) achieving a clinical response at 12 weeks.
The multinational trial, which examined filgotinib 100 mg or 200 mg daily, explored the use of the drug in patients with moderate to severe RA who had an inadequate response or intolerance to at least 1 biologic disease-modifying anti rheumatic drug (bDMARD).
FINCH 2 was a 24-week randomized, placebo-controlled, phase 3 trial that was conducted between July 2016 and June 2018 at 114 sites, which included hospitals, clinics, academic centers, and private research sites, internationally. The trial included a total of 448 patients who were randomized in a 1:1:1 ratio to receive filgotinib 200 mg, filgotinib 100 mg, or placebo tablets.
All patients included were 18 or older with a diagnosis of RA, 6 or more swollen joints, and 6 or more tender joints at both screen and baseline. Additionally, patients needed a serum C-reactive protein (CRP) level of 4 mg/L and bDMARDs needed to be discontinued 4 or more weeks prior to randomization.
The mean age of patients treated was 56 years and 80.4% (360) of the participants were women. All patients included within the study, whether randomized to filgotinib or placebo, continued use of 1 to 2 pre-specified stable conventional synthetic DMARDs.
The primary end point of the FINCH 2 trial was the proportion of patient with an American College of Rheumatology 20% (ARC20) response at week 12. Investigators noted that the secondary efficacy end pints included change from baseline in Health Assessment Questionnaire-Disability Index (HAQ-DI) score, proportion of patients with disease activity score in 28 joints count, and change from baseline in the 36-item Health Assessment Questionnaire-Disability Index, 36-item Short-Firm Health Survey Physical Component, and Functional Assessment of Chronic Illness Therapy-Fatigue scores, as well as a week 24 assessment of remission and adverse events.
Results of the analysis demonstrated that more patients receiving filgotinib 200 mg (66%) or 100 mg (57.5%) achieved ACR20 response (placebo, 31.1%; difference vs placebo: 34.9% [95% CI, 23.5%-46.3%] and 26.4% [95% CI, 15.0%-37.9%], respectively; both P < .001). Investigators noted similar results among those with prior exposure to 3 bDMARDS or more (70.3%, 58.8%, and 17.6%, respectively; difference vs placebo: 52.6% [95% CI, 30.3%-75.0%] for filgotinib, 200 mg, and 41.2% [95% CI, 17.3%-65.0%] for filgotinib, 100 mg; both P < .001).
For 200 mg filgotinib, the most commonly reported adverse event was nasopharyngitis (10.2%). In the 100 mg filgotinib group, headache, nasopharyngitis, and upper respiratory infection (5.9% each) were the most commonly reported adverse events. Among those who received placebo, RA (6.7%) was most common.
Investigators noted 4 uncomplicated herpes zoster cases an d 1 retinal vein occlusion within the filgotinib groups. Additionally, they found no instances of opportunistic infections, active tuberculosis, malignancies, gastrointestinal perforation, or deaths.
In an invited commentary published in JAMA, Jasvinder Singh, MBBS, MPH, professor of medicine and epidemiology at the University of Alabama at Birmingham, wrote that the results of the study were encouraging but additional trials would be needed to compare efficacy head-to-head with other RA treatments. Singh added that while new therapies for treating RA are in high demand, keeping out-of-pocket costs of the patients in mind is paramount.
"RA is a heterogeneous disease, and a significant proportion of patients with RA are either nonresponders or are intolerant to all current therapies However, to help promote use, these oral JAK inhibitor therapies will need to be priced at levels comparable with the conventional synthetic DMARDs rather than the biologics," Singh explained. "Patients and clinicians express frustration over the high pricing of new RA therapies because a portion of the cost is often passed on to the patients by the health insurance plan, which limits access to these therapies."
This study, titled “Effect of Filgotinib vs Placebo on Clinical Response in Patients With Moderate to Severe Rheumatoid Arthritis Refractory to Disease-Modifying Antirheumatic Drug Therapy,” is published in JAMA.
In addition to trials evaluating safety and efficacy as a treatment for RA, is being examined in clinical trials for ankylosing spondylitis, uveitis, psoriatic arthritis, and lupus nephropathy among others. Filogitinib is also being evaluated via phase 3 clinical trials for the treatment of Crohn’s Disease and ulcerative colitis.