The main purpose of this study is to evaluate the safety, efficacy and tolerability of ARGX-117 in Deceased Donor Kidney Transplant Recipients at Risk for Delayed Graft Function.

The study consists of 2 parts: part A comprises the main study period, and part B comprises the long-term observational follow-up period. During part A, after the screening period, eligible participants will be randomized to receive either ARGX-117 or placebo, entering the treatment and evaluation period (duration of up to 52 weeks). After the treatment period, participants will enter a follow-up period of up to 12 weeks.

The total study duration varies from approximately 64 weeks up to 5 years post-transplant depending on whether a participant enrols in part B of the study.

Inclusion Criteria:

• Is at least the local legal age of consent for clinical studies and at least aged 18 years and less than 70 years
• Agree to use contraceptive measures consistent with local regulations
• Are diagnosed with ESRD and have been stable on chronic dialysis for at least 3 months
• Are recipients of de novo or second-time, single kidney transplant from a deceased donor, either DCD (donation after cardiac/circulatory death) or DBD ( (donation after brain death)
• Are ABO compatible with donor allograft, except for type A2 donor to type B recipient kidneys
• Have a negative cross match
• Have received pretransplant vaccinations for: Neisseria meningitidis, Streptococcus pneumoniae, and Haemophilus influenzae, or are willing to receive the vaccinations approximately 3 to 4 months posttransplant

Exclusion Criteria:

• Any history of prothrombotic disorder or history of thrombosis or hypercoagulable state, excluding vascular access clotting
• Any known history of complement deficiency
• Evidence of peritonitis in participants on peritoneal dialysis
• Received any solid organ, bone marrow, or hematopoietic stem cell transplant, with the exception of prior first kidney transplant
• High risk within the study period for recurrence of underlying renal disease in the opinion of the investigator
• Clinically significant comorbidity, recent major surgery (within 3 months of screening), history of any treatment nonadherence, or intention to have surgery during the study other than kidney transplantation; or any other medical condition that, in the investigator's opinion, would confound the results of the study or put the participant at undue risk
• Clinically significant active bacterial, viral, or fungal infection
• History of malignancy unless considered cured by adequate treatment, with no evidence of recurrence for 5 years or more before first study drug administration. Adequately treated participants with the following cancers can be included at any time: Basal cell or squamous cell skin cancer; Carcinoma in situ of the cervix; Carcinoma in situ of the breast; Incidental histological finding of prostate cancer
• History of current alcohol, drug, or medication abuse as assessed by the investigator
• Pregnant or lactating state or intention to become pregnant during the study

The full list of criteria can be found in the protocol.