Simcere Pharmaceutical Group has announced a significant milestone in the development of SIM0278, its regulatory T cell (Treg)-preferential IL-2 mutant Fc fusion protein, which has officially entered Phase II clinical trials in China for the treatment of moderate-to-severe atopic dermatitis. The first dose was administered at Hangzhou First People's Hospital, marking a crucial advancement in addressing unmet medical needs for this challenging skin condition.
Phase II Trial Design and Objectives
The Phase II study is designed as a randomized, double-blind, placebo-controlled, multi-center trial aimed at evaluating the efficacy, safety, and pharmacokinetics of continuous subcutaneous administration of SIM0278 in participants with moderate-to-severe atopic dermatitis. This comprehensive approach will provide critical data on the drug's therapeutic potential and safety profile in the target patient population.
Addressing Significant Medical Need
Atopic dermatitis represents a chronic, recurrent, inflammatory skin disease characterized by symptoms such as dry skin, intense itching, and erythema, which significantly impact patients' quality of life. According to the company, a high medical need for the treatment of moderate to severe AD remains, creating opportunities to further optimize treatment options and technologies.
Novel Mechanism of Action
SIM0278 was developed on Simcere's proprietary protein engineering platform and represents an innovative approach to immune modulation. The drug's mechanism of action involves introducing mutations that reduce its affinity for effector T cells while maintaining high affinity for regulatory T cells. This selectivity allows SIM0278 to activate Tregs specifically, helping to restore immune balance without affecting effector T cells or natural killer cells.
The critical role of Treg cells in peripheral immune tolerance has become a major focus in current immunology research and was recently recognized with the 2025 Nobel Prize, highlighting the scientific significance of this therapeutic approach.
Promising Phase I Results
SIM0278 has demonstrated encouraging results in its completed Phase I clinical study in China, showing good tolerability, appropriate pharmacokinetic properties, and preliminary efficacy. These positive outcomes have positioned the drug as a potential best-in-class product with the expectation of achieving sustained efficacy across various immune disorders.
Global Development Strategy
The advancement to Phase II trials represents a significant step forward in SIM0278's global clinical development plan. In September 2022, Simcere signed an exclusive license agreement with Almirall, S.A., granting Almirall rights to develop and commercialize SIM0278 for all indications outside Greater China. The Phase I clinical study conducted by Almirall in the United States has been completed, and a Phase II study on another skin condition is scheduled to begin in the coming months.
Industry Perspectives
Karl Ziegelbauer, Chief Scientific Officer at Almirall, expressed enthusiasm about the development, stating, "We are excited about what SIM0278's entry into Phase II means for AD patients and the long-term management of the disease. This partnership reinforces our commitment to pushing the boundaries of science and patient-centric innovation to deliver impactful solutions for unmet dermatological needs."
Dr. Aik H Goh, Chief Medical Officer of Simcere, emphasized the strategic importance of this milestone: "The clinical progress of SIM0278 significantly strengthens Simcere's leading position in the field of autoimmune diseases. The initiation of Phase II clinical trials also marks a significant step forward in the project's global clinical development plan. We look forward to working with our partner to bring this innovative drug to patients worldwide as soon as possible."
