A randomized, double‐blind, placebo‐controlled phase 1b study to evaluate the safety, tolerability, and pharmacodynamics of an anti‐amyloid‐β antibody SHR‐1707 in patients with mild cognitive impairment and mild Alzheimer’s disease

Abstract

AbstractBackgroundSHR‐1707 is a humanized monoclonal antibody against amyloid‐β (Aβ). Pharmacodynamic studies in vitro showed that SHR‐1707 is more potent than lecanemab. SHR‐1707 had similar affinity to Aβ fibrils and protofibrils and relatively higher affinity to Aβ monomers than lecanemab. In 5xFAD transgenic mouse model of Alzheimer’s disease (AD), SHR‐1707 safely reduced brain Aβ deposition and ameliorated memory deficits. Phase 1 studies in China (NCT04973189) and Australia (NCT04745104) had demonstrated the safety and tolerability of SHR‐1707 in healthy young adults and elderly subjects at up to 60 mg/kg. The preclinical and clinical evidence support further development of SHR‐1707. Hence, we designed a phase 1b trial of SHR‐1707 to evaluate the safety, effective dosage, and effects on brain Aβ deposition in patients with mild cognitive impairment (MCI) due to AD or mild AD.MethodThis is a randomized, double‐blind, dose‐escalation, placebo‐controlled phase 1b study (NCT05681819; Figure 1). Patients with MCI due to AD or mild AD aged 55‐85 years will be randomized to placebo or intravenous SHR‐1707 at escalated doses of 5, 10, 20, and 40 mg/kg every 2 weeks for 26 weeks. Randomization will be based on the treatment to placebo ratio of 3:2 for 5 mg/kg dose group (N = 5, ≥3 ApoE ε4 carriers) and 10:2 for the remaining dose groups (for each group: N = 12, ≥5 ApoE ε4 carriers). In the following open‐label extension study, all patients will be assigned to SHR‐1707 for 52 weeks. The primary objective is to assess the safety and tolerability of 26‐week treatment of SHR‐1707. Secondary objectives are to assess effects on brain Aβ deposition by positron‐emission tomography, pharmacokinetic and pharmacodynamic profiles in blood and cerebrospinal fluid, immunogenicity, and clinical efficacy with 26‐week treatment of SHR‐1707; and long‐term safety, tolerability, and effects on brain Aβ deposition with 78‐week treatment. Figure 2 lists all study endpoints.ResultThe study is ongoing in China. Topline results are expected in Q1 2024.ConclusionThis trial will obtain safety, tolerability, pharmacokinetics, pharmacodynamics, immunogenicity, and clinical efficacy data of SHR‐1707 to support advancement to confirmatory phase 2 or 3 studies in patients with MCI due to AD and mild AD.