The endpoint of both drugs are quite similar to an extend. They...

The endpoint of both drugs are quite similar to an extend. They could work symbolically together. They both aim to reduce/prevent protein into the urine but the protein targets are quite different. FILSPARI® (sparsentan) targets the 'buildup deposits of the protein' immunoglobulin A (IgA) (a protein that helps the body fight infections) inside the filters (glomeruli) in the kidney. Note there is no scarring or ruptures in the kidney yet, just IgA getting clogged the kidney so essentially you want to prevent protein IgA from clogging your kidney filtering. Its more of a chronic kidney disease that lasts 10 -20 years eventually causing protein or blood to leak into the bladder or other renal related problems like FSGS. Also its noted that FILSPARI also has a toxicity warning related to liver toxicity, foetal toxicity and certain drug interactions.

FSGS on the other hand is more serious, almost feel like you're close to renal failure. In this disease you already started having protein leakage in the kidney filtration system. Symptom's at this point are pretty much foaming urine, swelling of hands and feet plus probably develop other health problems like diabetes, blood clots, blood pressure problems, kidney failures...etc. I believe DMX-200 is able to investigate how sparsentan work and use this research to its advantage to produce a drug that safer with less side effects and specifically target in the 'prevention of proteinuria (Albumin) and minimise/heal the filters' of the kidney to prevent further scarring. So yes specifically, DMX-200 is the only therapy in phase 3 development for 'FSGS'.

Anyways, based on my understanding I hope that helps.