Long-Term Safety and Efficacy Evaluation of Filgotinib in Rheumatoid Arthritis: An Open-Label Extension Study

The primary objective of this study is to evaluate the long-term **safety** and tolerability of **filgotinib** in subjects with rheumatoid arthritis who have completed one of the parent studies of filgotinib. This is clinically relevant as it aims to ensure that the therapeutic benefits of filgotinib are sustained without adverse effects over an extended period, which is crucial for chronic conditions like rheumatoid arthritis.

Secondary objectives include:

• Evaluating the long-term efficacy of filgotinib in subjects with rheumatoid arthritis.
• Assessing the long-term effects of filgotinib on subject-reported outcomes, such as disability, fatigue, and quality of life.

The clinical trial involves a total of **1554 participants** diagnosed with **rheumatoid arthritis**. The study population includes both male and female subjects, with an age range corresponding to categories 3 and 4, which typically encompass adults and older adults. Participants were selected based on their completion of a Gilead-sponsored filgotinib parent study for rheumatoid arthritis, either on study drug or standard of care therapy. The trial includes individuals who may benefit from filgotinib as assessed by the investigator. Participants are required to have stable doses of protocol-permitted rheumatoid arthritis medications prior to the study's commencement. The study population is characterized by a vulnerable group, indicating the inclusion of individuals who may require additional considerations. Lifestyle factors such as diet and physical activity are not specified, but female participants of childbearing potential must adhere to specific contraceptive measures during the study. The trial's primary objective is to evaluate the long-term safety and tolerability of filgotinib in this population.

The clinical trial is designed as a **multicenter, open-label, long-term extension study** to assess the safety and efficacy of **filgotinib** in subjects with **rheumatoid arthritis**. The primary objective is to evaluate the long-term safety and tolerability of filgotinib in subjects who have completed one of the parent studies of filgotinib in rheumatoid arthritis. The trial is expected to run from February 28, 2017, to May 28, 2025, with a maximum treatment period of 312 days for each participant. The study involves the administration of Jyseleca film-coated tablets, available in 100 mg and 200 mg dosages, taken orally.

Participants will undergo a series of study visits, beginning with an inclusion (screening) visit to confirm eligibility based on specific criteria, such as completion of a Gilead-sponsored filgotinib parent study and the ability to provide informed consent. The study will include regular follow-up visits to monitor safety through adverse events, clinical laboratory tests, and vital signs. The secondary endpoint will assess ACR-N responses in each arm. The end-of-study visit will conclude the participant's involvement, ensuring all safety assessments are completed.

The expected length of participant involvement is up to 312 days, with conditions for early termination including non-compliance with study protocols or the occurrence of adverse events that necessitate withdrawal. Participants must adhere to protocol-specified methods of contraception and discontinue nursing if applicable. The study is not classified as low intervention and is categorized under Phase III, focusing on safety and efficacy. The trial does not include a pediatric formulation, and the active substance, filgotinib, is of chemical origin.

The clinical trial involves the administration of **Jyseleca 100 mg film-coated tablets**, which contain the active substance **filgotinib**. This medication is provided in the form of film-coated tablets and is intended for **oral use**. The maximum daily dose is 100 mg, with a total treatment period extending up to 312 days. The tablets are of chemical origin and are not formulated for pediatric use. The administration schedule requires participants to adhere to the prescribed dosage and frequency, with compliance monitored throughout the study duration.

Additionally, the trial includes the use of **Jyseleca 200 mg film-coated tablets**, also containing the active substance **filgotinib**. Similar to the 100 mg formulation, these tablets are designed for **oral use** and are chemically derived. The maximum daily dose for this formulation is 200 mg, with the same maximum treatment period of 312 days. As with the 100 mg tablets, these are not pediatric formulations. Participants are required to follow the dosing schedule precisely, and adherence is monitored to ensure compliance with the study protocol.

No non-experimental treatments, such as standard-of-care therapy, placebo, or comparator treatments, are specified in the trial documentation. The focus of the study is to evaluate the long-term safety and tolerability of filgotinib in subjects with **rheumatoid arthritis** who have completed one of the parent studies. The trial is conducted in an open-label format, allowing for direct observation of the treatment effects over the specified period.

The efficacy of **filgotinib** in the treatment of Rheumatoid Arthritis will be assessed in a multicenter, open-label, long-term extension study. The primary endpoint for evaluating efficacy is the safety profile, which will be monitored through adverse events (AEs), clinical laboratory tests, and vital signs. Secondary endpoints include the American College of Rheumatology-N (ACR-N) responses in each arm of the study. These endpoints will provide a comprehensive assessment of the drug's efficacy and safety over the course of the trial.