Inclusion Criteria for Cohort A and B:
Written informed consent must be obtained before any assessment is performed
Male and female patients between the ages of 18 to 65 (inclusive) at screening
C3G patients wit proteinuria
Able to communicate well with the investigator, to understand and comply with the requirements of the study
At screening and baseline visits, patients must weigh at least 35 kg
Supine vital signs should be within the following ranges :
oral body temperature between 35.0-37.5 °C systolic blood pressure, 80-170 mm Hg diastolic blood pressure, 50-105 mm Hg pulse rate, 45 - 100 bpm
Inclusion Criteria for Cohort A:
Estimated GFR (using the CKD-EPI formula) or measured GFR ≥30 mL/min per 1.73 m2 for patients on a maximum recommended or maximum tolerated dose of an angiotensin converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB)
UPCR ≥ 100 mg/mmol (equivalent to ≥ 1 g/24h total urinary protein excretion)
Prior to entry, all patients must have been on supportive care including a maximally tolerated dose of ACEi or ARB for at least 30 days.
Inclusion Criteria for Cohort B:
No histological/laboratory/clinical signs of allorejection
If applicable, induction treatment after allotransplantation needs to be completed >30 days before inclusion.
Transplantation of a kidney allograft >90 days before inclusion
Patients need to be on a stable dose of immunsuppressive regimen prior to inclusion. Any approved treatments are allowed for this purpose.
Exclusion Criteria for Cohort A and B:
Use of other investigational drugs at the time of enrollment, or within 5 half-lives of randomization, or within 30 days, whichever is longer; or longer if required by local regulations
A history of clinically significant ECG abnormalities,
Known family history or known presence of long QT syndrome or Torsades de Pointes
Use of agents known to prolong the QT interval unless they can be permanently discontinued for the duration of the study
Pregnant or nursing (lactating) women, where pregnancy is defined as the state of a female after conception and until the termination of gestation, confirmed by a positive hCG laboratory test.
Women of child bearing potential, defined as all women physiologically capable of becoming pregnant, unless they are using highly effective methods of contraception during dosing and for 1 week after stopping of investigational drug.
History of immunodeficiency diseases, or a positive HIV (ELISA and Western blot) test result.
Chronic infection with Hepatitis B (HBV) or Hepatitis C (HCV).
Patients who cannot receive vaccinations against N. meningitidis, S. pneumoniae, or H. influenzae