Ep. 8 – New Frontiers in FSGS: A Discussion of Recent Data and Developments (with Dr. Howard Trachtman)

In this episode, Bluestar Principal Jeff Fineberg is joined by Dr. Howard Trachtman, a pediatric nephrologist and researcher, who has been a principal investigator on many NIH- and industry-sponsored clinical trials in glomerular diseases, including FSGS. Following a brief recap of the recent history of sparsentan in FSGS, and some recent developments in its hopeful path toward FDA approval, Jeff and Dr. Trachtman define what FSGS really is, before the two of them dive into the long-term efficacy and safety data of sparsentan in FSGS from the DUET and DUPLEX clinical trials. This includes a discussion of the PARASOL working group, and their efforts to find good surrogate endpoints for clinical trials in FSGS. From there, the conversation turns toward treatment response rates and durability of remission as observed in a recent study, and the implications toward finding biomarkers for both better targets, as well as a more personalized approach to FSGS therapy. Finally, Dr. Trachtman shares the results of a recent clinical trial of BI-764198, a TRPC6 inhibitor from Boehringer Ingelheim, in development for FSGS, including the rationale for this target, and what we can conclude from the study results. Chapters 00:00 - Intro. 03:40 - What is FSGS? 07:25 - Can near-term changes in proteinuria quantitatively predict long-term outcomes in FSGS? (DUET and DUPLEX Trials of Sparsentan in FSGS). 14:00 - The PARASOL Working Group to find surrogate endpoints in FSGS. 20:40 - Are there certain patient subgroups for whom we can tailor therapy in FSGS? (Treatment response rates and kidney outcomes in FSGS). 25:20 - Potential for additional diagnostics to predict treatment response. 28:30 - What is TRPC6, and what is its role in FSGS? 30:45 - A double-blind RCT of BI-764198, a TRPC6 inhibitor, in FSGS. 37:40 - Closing thoughts. Article links Campbell, et al., 2024, Kidney Medicine Sim, et at., 2025, CJASN Trachtman, et al., 2026, Lancet