Safety and Effectiveness of Propagermanium in Focal Segmental Glomerulosclerosis Participants Receiving Irbesartan

This study will be evaluating the safety and efficacy of propagermanium for the treatment of participants with FSGS who are already taking irbesartan by: * monitoring symptoms that participants may experience while on the study, * measuring levels of protein in participant's urine and kidney function during the course of the study, * measuring the levels of propagermanium and irbesartan that enters into participant's urine and blood, and * comparing the propagermanium outcomes to participants' pre-study and placebo outcomes. Eligible participants will randomly be assigned to one of two arms to receive both the propagermanium and placebo in different orders as follows, either: Treatment Period 1 taking a propagermanium capsule twice a day for 16 weeks, followed by a six week washout period followed by Treatment Period 2 taking a placebo capsule twice a day for 16 weeks. OR Treatment Period 1 taking a placebo capsule twice a day for 16 weeks, followed by a six week washout period followed by Treatment Period 2 taking a propagermanium capsule twice a day for 16 weeks.