Ledequimab Demonstrates Rapid Onset Within 2 Weeks and Sustained Efficacy Through 52 Weeks in Phase III Trial for Moderate-to-Severe Atopic Dermatitis, Highlighted in Late-Breaking Oral Presentation at AAD Annual Meeting

On March 30, Simcere Pharmaceutical (2096.HK) announced that the Phase III clinical study of ledebasemab, an innovative antibody drug developed in collaboration with ConquerBiopharma for adult and adolescent patients with moderate-to-severe atopic dermatitis, was selected as a Late-Breaking Abstract (LBA) for oral presentation at the 84th Annual Meeting of the American Academy of Dermatology.

Research data show that ledelibartan rapidly relieves pruritus and improves skin inflammation within two weeks, with the efficacy of deep clearance of skin lesions sustained for up to 52 weeks. The study was co-led by Professor Zhang Jianzhong and Professor Zhou Cheng from Peking University People’s Hospital as principal investigators. On March 28, Professor Zhou Cheng presented the findings on behalf of the research team to the international academic community at a conference in Denver, Colorado, USA.

Atopic dermatitis (AD) is primarily characterized by chronic, eczema-like rashes that recur frequently, accompanied by significant skin dryness and pruritus. It is estimated that there are approximately 70 million AD patients in China, with the number showing an upward trend. Among them, nearly 50% suffer from moderate-to-severe disease. Due to its large patient population and substantial impact on quality of life, AD is referred to as the “number one disease” in dermatology. Although biologics have been launched, clinical practice still faces challenges such as insufficient rates of deep remission and high recurrence, leaving current treatment options limited. There is an urgent need for new drugs with superior efficacy and safety profiles.

In this randomized, double-blind, placebo-controlled Phase III clinical trial (RADIANT-AD, NCT06477835), a total of 259 adult and adolescent subjects with moderate-to-severe AD were enrolled. Patients were randomly assigned in a 1:1 ratio to receive ledekipimab or placebo for 16 weeks, followed by a 36-week open-label period during which all subjects received ledekipimab.

At Week 16, the proportion of patients receiving ledeciqumab who achieved the following efficacy endpoints was significantly superior to that in the placebo group (p<0.0001):

At Week 52, the efficacy of ledebalimab was sustained and further demonstrated, with the proportions of patients achieving the aforementioned endpoints being 87.1%, 96.6%, 85.3%, and 91.2%, respectively.

Ladekibart demonstrated a favorable safety profile during long-term treatment (0–52 weeks), consistent with other anti-IL-4 monoclonal antibodies. At Week 16, the incidence of treatment-emergent adverse events (TEAEs) was 60.9% in the ladekibart group and 64.9% in the placebo group; by Week 52, the TEAE incidence in the ladekibart group was 82.2%. At Week 16, the rates of serious adverse events and permanent discontinuation due to adverse events were lower in the ladekibart group, and remained low through Week 52.

Professor Zhang JianzhongIt stated: “Ladekibart demonstrated a dual advantage in both efficacy and safety in clinical studies, with its long-term safety profile further bolstering clinical confidence. For clinical practice, the significance of ladekibart extends beyond merely adding another therapeutic option; it holds promise as a key driver in continuously elevating treatment goals for moderate-to-severe atopic dermatitis (AD) and facilitating the implementation of standardized long-term disease management.”

Professor Zhou Cheng“It demonstrates that lecanemab exhibits the ability to sustain deep remission of Alzheimer’s disease (AD) symptoms, with rapid onset of action, further enhanced benefits upon continuous treatment, and a favorable safety profile. This suggests that the drug has the potential to address the core challenges in the long-term management of patients with moderate-to-severe AD, providing clinicians and patients with a safe and effective new therapeutic option.”

Ledectibart is a fully human monoclonal antibody targeting IL-4Rα. Preclinical studies have demonstrated that it exhibits higher affinity for the receptor than dupilumab, inhibits the biological activities of IL-4 and IL-13, and exerts therapeutic benefits in inflammatory diseases such as atopic dermatitis (AD) and asthma by blocking the Th2-mediated inflammatory pathway.

In November 2023, Simcere entered into an exclusive license and collaboration agreement with ConnoMed, securing exclusive rights to develop, manufacture, and commercialize lecanemab for all indications in the Greater China region. Subsequently, Simcere collaborated with experts from 59 clinical centers across China to rapidly initiate a pivotal Phase III clinical study of the drug for the treatment of Alzheimer’s disease (AD), which has achieved its primary endpoint. The release of these Phase III clinical data provides robust evidence of the drug’s differentiated clinical value. In July 2025, the National Medical Products Administration (NMPA) accepted the New Drug Application (NDA) for lecanemab, holding promise for delivering a more effective therapeutic option for AD patients in China.