This study is a single center, randomized, double-blind, placebo-controlled Phase I clinical study in a single dose escalation to evaluate its safety, tolerability, pharmacokinetics, pharmacodynamics, and immunogenicity of CM383 in male healthy subjects.

Alzheimer's disease (AD) is the most common type of dementia, which is a degenerative disease of the central nervous system with insidious onset and progressive development. Its clinical features mainly include memory impairment, cognitive impairment, psychobehavioral abnormalities, and social decline.

Inclusion Criteria:

• Healthy males, voluntarily participate;
• 18 and 80 years old (including boundary values);
• able to communicate well with the researchers and follow up the protocol requirements.

Exclusion Criteria:

• The average daily smoking volume within three months before screening is greater than 5 cigarettes;
• Excessive alcohol consumption within three months before screening, or positive alcohol breath test;
• Urine drug abuse screening is positive;
• Having a family planning or sperm donation plan; Disagree to adopt efficient contraceptive measures.