Evaluation of Step-Up Versus Step-Down Therapeutic Strategies in Juvenile Idiopathic Arthritis Using Etanercept and Methotrexate Combination Therapy

The primary objective of this study is to compare the effectiveness of two therapeutic strategies in the management of **juvenile idiopathic arthritis**. The first strategy is a conventional therapeutic regimen that involves treatment escalation, known as the Step-up strategy, which is guided by the treat-to-target approach. The second strategy is an early aggressive intervention that combines conventional and biological disease-modifying antirheumatic drugs (DMARDs), referred to as the Step-down strategy. This comparison is clinically relevant as it aims to determine the most effective approach for achieving optimal disease control in pediatric patients, potentially influencing treatment guidelines and improving patient outcomes.

The clinical trial involves participants diagnosed with **juvenile idiopathic arthritis**. The study population includes both male and female subjects, aged between 2 to 16 years, who are newly diagnosed and have not previously been treated with synthetic or biologic DMARDs, except for one NSAID. Participants must have active arthritis and the onset of symptoms must have occurred no more than six months prior to randomization. The trial includes a vulnerable population, as it involves children. Female participants of child-bearing potential are required to have a negative pregnancy test at the start of the trial and must use highly effective contraceptive measures if sexually active. Similarly, post-pubertal males must agree to use effective contraception if sexually active. The ability to comply with study procedures and communicate effectively with the investigational staff is necessary, and informed consent must be obtained from the parents or patients. The sponsor has not provided information regarding the total number of participants in the trial.

The clinical trial is designed to evaluate the effectiveness of two therapeutic strategies in the management of **juvenile idiopathic arthritis**. This is a randomized, double-blind, controlled trial comparing a conventional treatment escalation approach (Step-up strategy) with an early aggressive intervention combining conventional and biological DMARDs (Step-down strategy). The trial is expected to run from May 2019 to May 2026, with a primary endpoint of achieving clinical remission on or off medication at 12 months. Secondary endpoints include the rate of patients achieving the JADAS/JIA ACR state of inactive disease at any point during the study.

Participants will be involved in the study for a maximum of six months, with the treatment period being the same duration. The study will include several key visits: an initial screening visit to confirm eligibility, regular follow-up visits to monitor progress and adjust treatment as necessary, and a final end-of-study visit to assess outcomes. The inclusion criteria specify that participants must be newly diagnosed, DMARD-naïve children aged 2 to 16 years, with active arthritis and symptom onset no more than six months prior to randomization. Exclusion criteria are not specified in the provided data.

Participants may be withdrawn from the study early if they are unable to comply with study procedures, experience adverse effects, or if the investigator deems it necessary for their safety. The trial involves the administration of **etanercept** and **methotrexate**, both delivered subcutaneously in solution form. The maximum daily dose for etanercept is 7.1 mg, with a total dose limit of 1200 mg, while methotrexate has a maximum daily dose of 2.9 mg and a total dose limit of 480 mg. The trial is conducted under the sponsorship of Pfizer Europe MA EEIG and Alfasigma S.P.A., with the products being authorized for use in the European Union and Italy, respectively.

The clinical trial involves the administration of **Enbrel**, a solution for injection containing the active substance **etanercept**. Enbrel is available in pre-filled syringes with dosages of 25 mg and 50 mg, as well as a 10 mg powder and solvent formulation for pediatric use. The pharmaceutical form is a solution for injection, and the route of administration is subcutaneous. The maximum daily dose is 7.1 mg, with a total maximum dose of 1200 mg over a treatment period of up to 6 months. Enbrel is produced by Pfizer Europe MA EEIG and is classified under the ATC code L04AB01. Participant compliance with the dosing schedule will be monitored throughout the trial.

Additionally, the trial includes the administration of **Reumaflex**, which contains the active substance **methotrexate**. Reumaflex is provided as a 50 mg/ml solution for injection in pre-filled syringes. The pharmaceutical form is a solution for injection, administered subcutaneously. The maximum daily dose is 2.9 mg, with a total maximum dose of 480 mg over a 6-month treatment period. Reumaflex is manufactured by Alfasigma S.P.A. and is classified under the ATC code L04AX03. Compliance with the dosing regimen will be closely monitored to ensure adherence to the study protocol.

Efficacy in this clinical trial will be assessed using both primary and secondary endpoints. The primary endpoint is the achievement of clinical remission on or off medication at 12 months. This will be evaluated to determine the effectiveness of the treatment strategies being compared. The secondary endpoint involves comparing the rate of patients who achieve the Juvenile Arthritis Disease Activity Score (JADAS) or the Juvenile Idiopathic Arthritis (JIA) American College of Rheumatology (ACR) state of inactive disease (ID) at any single point in time throughout the study period between the two treatment arms. These endpoints will provide a comprehensive assessment of the treatment efficacy in managing juvenile idiopathic arthritis.