This study is an exploratory, randomized, double-blind, multicenter, placebo-controlled study with repeated doses of AP1189. The study population will consist of patients with idiopathic membranous nephropathy (iMN) and severe proteinuria who are on ACE inhibitor or angiotensin II receptor blocker treatment.
Written informed consent has been obtained prior to initiating any study-specific procedures
Male and female subjects, 18 to 85 years of age diagnosed with iMN within 6 months prior to inclusion
Diagnosed as anti-PLA2-Receptor positive by local laboratory within 6 months prior to inclusion
Severe proteinuria defined by a U-protein/creatinine ratio >3.0 g/g and/or U-albumin/creatinine ratio >2.0 g/g and a P-albumin below the lower normal limit
Participation in any other study involving investigational drug(s) during the study and within 4 weeks prior to study entry
Clinicial findings that in the opinion of the investigator would suggest condition(s) other than iMN as a major cause of severe proteinuria
Major surgery within 8 weeks prior to screening or planned surgery within 1 month following randomization
Blood pressure with systolic pressure above 160 mmHg and/or diastolic pressure above 100 mmHg despite antihypertensive treatment will in all cases be considered "uncontrolled"