Phase IB Open-Label Extension Basket Trial of RAY121 in Classical Complement Pathway Inhibition for Various Immunological Diseases

The primary objective of this study is to evaluate the efficacy of **RAY121** in inhibiting the classical complement pathway in patients with various **immunological diseases**. This is clinically relevant as the classical complement pathway plays a significant role in the pathogenesis of several autoimmune conditions, and its inhibition could potentially ameliorate disease symptoms and improve patient outcomes. The diseases under investigation include **Immune Thrombocytopenia**, **Antiphospholipid syndrome**, **Behçet’s Syndrome**, **Immune-mediated necrotizing myopathy**, **Bullous pemphigoid**, and **Dermatomyositis**. The study is designed as a Phase IB open-label, long-term extension basket trial, known as the RAINBOW-LTE trial.

The clinical trial involves a total of **66 participants** diagnosed with conditions such as **Immune Thrombocytopenia**, Antiphospholipid syndrome, Behçet’s Syndrome, immune-mediated necrotizing myopathy, bullous pemphigoid, and dermatomyositis. The study population includes both male and female subjects, with an age range that spans from 18 to 64 years. Participants were selected without targeting any vulnerable populations. The trial does not specify any particular lifestyle considerations such as diet or physical activity. The sponsor has not provided detailed information regarding the principal inclusion or exclusion criteria for this study.

The clinical trial is designed as a **Phase IB open-label, long-term, extension basket trial** to evaluate the efficacy of RAY121 in inhibiting the classical complement pathway in various **immunological diseases**. The trial will include participants diagnosed with conditions such as **Immune Thrombocytopenia**, **Antiphospholipid syndrome**, **Behçet’s Syndrome**, **Immune-mediated necrotizing myopathy**, **Bullous pemphigoid**, and **Dermatomyositis**. The trial is expected to commence recruitment on March 1, 2025, and conclude by December 28, 2026.

The trial will follow a structured sequence of study visits, beginning with an inclusion (screening) visit to assess eligibility based on predefined criteria. Participants who meet the inclusion criteria will be enrolled in the study. Throughout the trial, participants will attend regular follow-up visits to monitor their response to the treatment and assess any adverse events. The end-of-study visit will mark the completion of the participant's involvement, during which final assessments will be conducted to evaluate the overall outcomes of the treatment.

Participant involvement is expected to last until the end of the trial in December 2026, unless early termination is warranted. Conditions that may lead to early termination include significant adverse events, withdrawal of consent, or any other protocol-defined criteria. The trial's methodology ensures rigorous monitoring and data collection to maintain the integrity and reliability of the study outcomes.

The clinical trial documentation does not provide specific details regarding the experimental medication, including its name, pharmaceutical form, dosage, route, and frequency of administration. Consequently, no detailed description of the experimental treatment can be provided based on the available data.

Similarly, there is no information available about any non-experimental treatments used in the study, such as standard-of-care therapy, placebo, or comparator treatment. As such, no description of these elements can be included.

Additional relevant information about drug administration, dosing schedules, and participant compliance monitoring is also not provided in the source data. Therefore, no further details can be offered regarding these aspects of the clinical trial.

The clinical trial is designed to assess efficacy in a Phase 3 study. The trial is scheduled to commence recruitment on March 1, 2025, with an estimated completion date of December 28, 2026. The efficacy assessment will be conducted through a series of planned evaluations, although specific parameters or endpoints for efficacy evaluation are not detailed in the provided data. The trial will follow a structured timeline to ensure systematic data collection and analysis. The methods and tools for measuring efficacy, as well as the specific timepoints for these assessments, are not specified in the available information. The trial's focus on efficacy is aligned with the objectives typical of a Phase 3 study, which generally aims to confirm the effectiveness of a treatment in a larger patient population. The trial's design and execution will adhere to rigorous standards to ensure the reliability and validity of the efficacy data collected.