A Study of the C3 Complement Inhibitor AMY-101 in Adults With Gingivitis

Inclusion Criteria: 1. Provision of signed and dated informed consent form. 2. Stated willingness to comply with all study procedures and availability for the duration of the study. 3. Age 18-65 years old. 4. Equal to or greater than 18 natural teeth present (excluding third molars). 5. Generalized periodontal inflammation determined by modified gingival index and percent bleeding on probing (MGI≥2.0, BOP ≥ 40%). 6. In good general health as evidenced by medical history. 7. For women of reproductive potential, use of licensed hormonal contraception or barrier methods or abstinence for at least 1 month prior to screening and agreement to use such a method during study participation. 8. For men of reproductive potential, agreement to use condoms or other methods to ensure effective contraception with partner. Exclusion Criteria: 1. Presence of orthodontic appliances (including fixed lingual retainer). 2. A soft or hard tissue tumor of the oral cavity. 3. Carious lesions requiring immediate treatment. 4. Participation in any other clinical study within 30 days of screening or during the study. 5. Antibiotic therapy within the last 30 days. 6. Chronic use (≥3 times/week) of anti-inflammatory medications \[e.g., non-steroidal anti-inflammatory drugs (NSAIDs), steroids\]. Low dose (\<325 mg) aspirin is allowed. 7. Immune compromised subjects (e.g., subjects with HIV infection, neutropenia, complement deficiency, etc.). 8. Any medical history or any concomitant medication that might affect the assessment of the study treatment or periodontal tissues, such as diabetes (irrespective of level of control), rheumatoid arthritis, Crohn's disease, nifedipine, phenytoin (Dilantin), anticoagulant medications (e.g., warfarin \[Coumadin\] etc.), ongoing cancer treatment either with radiation or chemotherapy. 9. Involvement in the planning or conduct of the study. 10. History of any clinically significant disease or disorder which, in the opinion of the investigator, may either put the subject at risk because of participation in the study, or interfere with interpretation of the subject's study results. 11. Pregnancy or lactation. 12. Uncontrolled chronic diseases (e.g., kidney disease, COPD, pulmonary fibrosis, Hepatitis C) 13. Autoimmune disorders (Down's Syndrome, Sjogren's Disease, Psoriasis, Chediak-Higashi Syndrome) 14. Conditions requiring antibiotic prophylaxis. 15. Periodontal therapy within the past one year. 16. Gross tooth decay, as determined by the investigator. 17. Periodontal or dental abscesses. 18. Root fragments, pericoronitis, endo-perio lesions. 19. Use of cigarettes or other tobacco products (including e-cigarette or recreational drug use) within 1 year before the screening visit.