A Phase I Trial of Subcutaneous QLS7305 in Healthy Adults

The goal of this clinical trial is to evaluate the safety, tolerability, and preliminary characteristics of the investigational drug QLS7305 in healthy adult participants in China. The main questions it aims to answer are:

What is the safety and tolerability profile of single and multiple subcutaneous doses of QLS7305 in healthy adults? What are the pharmacokinetic (PK) characteristics of QLS7305 and its major metabolites? What are the pharmacodynamic (PD) effects of QLS7305 on the complement system (e.g., serum C3 levels and complement activity)? Does QLS7305 induce an immunogenic response (anti-drug antibodies)? What is the effect of QLS7305 on the QTc interval? Investigators will compare different dose levels of QLS7305 to a placebo group to see the effects on safety, tolerability, and the measured parameters.

Participants will:

Be enrolled in one of two parts of the study:

Part A (Single Ascending Dose): Receive a single dose of QLS7305 or placebo. Part B (Multiple Ascending Dose): Receive multiple doses of QLS7305 or placebo (doses selected based on Part A results).

Receive prophylactic antibiotics (Penicillin V) after the first dose until their serum complement C3 level recovers, as a safety precaution.

Undergo close safety monitoring throughout the study, including a follow-up period of up to 337 days to ensure safety parameters return to acceptable levels.