A Study of SNP-ACTH (1-39) Gel in Patients With Primary Membranous Nephropathy

This head-to-head, open-label, 2-phase superiority trial compares SNP-ACTH (1-39) Gel to rituximab in the treatment of PMN that commences with an adaptive trial design for dose finding. The trial will be divided into 2 parts: Phase 3a and Phase 3b. Dose finding Phase 3a part of the study will enroll up to 24 patients randomized to 2 different dose levels of SNP-ACTH (1-39) Gel treatment for 12 months. Dose levels will be: * approximately 12 patients at 3mg SNP-ACTH Gel subcutaneous (sc) injection 3 times per week; * approximately 12 patients at 5mg SNP-ACTH Gel sc injection 3 times per week Data from the Phase 3a part of the study will be assessed at regular intervals (at months 2, 3, 4, 5, 6, 9, 12) and will inform the dose selection for the Phase 3b. The optimal dose will be determined based on a risk/benefit assessment from data obtained from the Phase 3a part of the study, with the earliest assessment being conducted after all patients have completed at least 2 months of therapy. The Phase 3b part of the study will enroll 132 patients randomized 1:1 to either 12 months of 1g Rituximab therapy (2 treatment cycles at month 1 and month 6) or 12 months of SNP-ACTH (1-39) Gel treatment at the dose level determined in the Phase 3a.