First-in-human Trial of RBD2080 in Healthy Participants

The goal of this clinical trial is to evaluate the safety, tolerability, dose-dependent pharmacokinetics and pharmacodynamics effects of RBD2080 in healthy volunteers to inform its further development for the treatment of patients with complement-mediated diseases. Participants will: * Be vaccinated against encapsulated bacterial infection prior to any IMP administration * Receive single or multiple doses of RBD2080 or placebo and attend 10-11 visits to the trial site for checkups and tests until End of trial (EoT). * Following End of trial visit, participants may enter an open-label follow-up period consisting of additional outpatient visits.

Key Inclusion Criteria: 1. Willing and able to give written informed consent for participation in the trial. 2. Healthy male or female participant aged 18 to 50 years. 3. BMI ≥ 18 and ≤ 32.0 kg/m2 at the time of the screening period. 4. Medically healthy without abnormal clinically significant medical/surgical history, physical findings, vital signs, ECG, and laboratory values at the time of the screening period, as judged by the Investigator. 5. Vaccinated against meningococcal disease (caused by Neisseria meningitidis) with a meningococcal ACWY conjugate vaccine and a serogroup B vaccine, or willing to be vaccinated against meningococcal disease, Streptococcus pneumoniae vaccine, Haemophilus influenzae type B vaccine during the screening period of the trial. Key Exclusion Criteria: 1. History of any clinically significant disease or disorder which, in the opinion of the Investigator, may either put the participant at risk because of participation in the trial, or influence the results or the participant's ability to participate in the trial. 2. Known or suspected hereditary asymptomatic complement deficiency. 3. Any clinically significant illness, medical/surgical procedure, or trauma within four weeks of the first administration of IMP. 4. Malignancy within the past five years, with the exception of in situ removal of basal cell carcinoma. 5. Any planned major surgery within the duration of the trial. 6. Extensive tattoos covering all potential injection areas, extensive scarring, or other barriers to subcutaneous injection, as judged by the investigator. 7. Participants who are pregnant, currently breastfeeding, or intend to become pregnant during the course of the trial. 8. At community risk for contracting meningococcal/ pneumococcal/Hib disease, at the discretion of the Investigator. Including recent contact with meningococcal disease and/or recent travel to risk areas for meningococcal disease contagion.