The primary objective is to demonstrate the immunological non-inferiority between GC3102C and GC FLU inj. influenza vaccines by assessing geometric mean titers(GMTs) in healthy adults

Inclusion Criteria:

• Healthy adults, 18 to <60 years old
• Subjets willing to provide written informed consent and able to comply with the requirements for the study

Exclusion Criteria:

• Subjects with a history of hypersensitivity, especially anaphylactic reactions to egg, egg proteins, chicken or components of vaccine such as gentamicin, gelatin, and arginine
• Subjects with a history of Guillain-Barré syndrome
• Subjects with severe chronic diseases (e.g., cardiovascular diseases without controllable hypertension, hemoglobinopathy, respiratory, metabolic, and renal disorders) who are considered by the investigator to be ineligible for the study
• Subjects previously treated with anti-coagulant therapy or hemophiliac patients who may be at risk of severe hemorrhage after an intramuscular injection
• Subjects who have had an acute febrile (at least 38.0°C) episode at some time during the 72 hours before enrollment
• Subjects who have received a vaccination within 7 days before enrollment or who are scheduled for another vaccination (excluding the study vaccine) during the study
• Immunocompromised subjects with immunodeficiency diseases or those who are receiving immunosuppressive or immunomodulatory therapy, e.g., azathioprine, cyclosporin, interferon, granulocyte-colony stimulating factor, tacrolimus, everolimus, sirolimus
• Subjects who have received high-dose corticosteroids in the 3 months before vaccination or who will be administered a cumulative dose of 700 mg of corticosteroids during the study. Inhaled, intranasal, and local application of corticosteroids is permitted, regardless of dosage, and corticosteroids such as prednisolone at a maximum dose of 15 mg/day are allowed
• Subjects who have been administered immunoglobulins or blood-derived products 3 months before enrollment or who are scheduled for the administration during the study
• Subjects who have received an influenza vaccine within 6 months of enrollment
• A female subject who is pregnant or who is breast-feeding. Subjects of childbearing potential without an appropriate contraceptive measure within 30 days before enrollment and who do not agree to use a clinically acceptable method of birth control during the study (e.g., oral contraceptives, condom, diaphragm or intrauterine device, or vasectomy of male partner)
• Subjects who have participated in any other clinical trials within 30 days of the administration of the study vaccine
• Individuals with other clinically significant medical or psychological condition who are considered by the investigator to be ineligible for the study