This study is a randomized, double-blind, placebo-controlled single ascending dose study of SGB-9768 in healthy volunteers. The purpose is to evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of subcutaneously administered SGB-9768.

It is a phase 1, randomized, double-blind, placebo-controlled single ascending dose study of SGB-9768. The primary objective is to evaluate the safety, tolerability of SGB-9768 when administered subcutaneously as a single dose to healthy volunteers. The secondary objective is to characterize the pharmacokinetics and pharmacodynamics of subcutaneously administered SGB-9768 in healthy volunteers.

Inclusion Criteria:

• Male and female subjects aged 18 to 55 years are included at the time of informed consent.
• Body mass index between 18 and 28 kg/m2 at screening, inclusive, at screening a weight of at least 45 kg for female and 50 kg for male.
• Physical examination, vital signs, 12-lead electrocardiogram, and laboratory tests be normal or slightly abnormal but not clinically significant according to investigator's judgement.
• Women of child-bearing potential who are not exclusively in same-sex relationships and males with partners of child-bearing potential must agree to use adequate contraception from signing the informed consent until 12 weeks after completion of the follow-up visit.
• Willing to comply with the protocol required visit schedule and visit requirements and provide written informed consent.

Exclusion Criteria:

• A history of or current surgical or medical condition that, in the opinion of the Investigator, may put the subject at significant risk (according to Investigator's judgment) or interfere with the subject's participation in the clinical study.
• History of or evidence of tuberculosis.
• History of recurrent or chronic infections.
• Subjects with a history of meningococcal infection, or subjects who are exposed to Neisseria meningitidis.
• History of asplenia or splenectomy.
• History of abnormalities in complement or hereditary complement deficiency.
• Received an investigational agent within 30 days or 5-half-lives (whichever is longer) before the first dose of the study drug or being in other clinical study.
• History or clinical evidence of drug abuse within 12 months before screening or positive screen for drugs of abuse.
• Used prescribed or over-the-counter medication within 14 days or 5 half-lives (whichever is longer) before the first dose of the study drug unless determined not clinically relevant by the Investigator.
• Any conditions which, in the opinion of the Investigator, would make the subject unsuitable for enrollment or could interfere with the subject's participation in or completion of the study.