EXTON, PA, Aug. 21, 2025 (GLOBE NEWSWIRE) -- The treatment landscape for focal segmental glomerulosclerosis (FSGS), a rare and often progressive kidney disease, is approaching a critical inflection point. New data from Spherix Global Insights’ seventh annual Market Dynamix™: FSGS (US) study highlight both the urgency for effective therapies and growing enthusiasm for late-stage pipeline agents, particularly to target APOL1-mediated disease.
In a survey of 102 U.S. nephrologists conducted in late June 2025, only about half of FSGS patients were considered ‘optimally managed,’ underscoring continued physician reliance on supportive care and systemic corticosteroids in the absence of FDA-approved, disease-targeted treatments. Despite this gap, physician sentiment points to mounting momentum for novel agents, especially those promising to reduce dependence on immunosuppressive regimens.
Emerging FSGS Drugs Like Filspari and Inaxaplin Capture Strong Physician Interest
Within a competitive field of ten emerging therapies, several brands are differentiating themselves through targeted mechanisms, potential for genetic subtyping, proven efficacy in other indications, and broad applicability across patient populations.
Many nephrologists indicate they would prescribe leading candidates quickly upon approval, with some considering off-label use in advance of regulatory clearance, highlighting the potential for Travere’s Filspari, Novartis’ Vanrafia, and Apellis’ Empaveli. Notably, physicians estimate that over 40% of their FSGS patients could be candidates for Filspari, reflecting the drug’s potential to impact a broad segment of the population.
Steroid-Sparing Strategies Gain Traction in FSGS Management
While supportive care with renin-angiotensin-aldosterone system inhibitors (RAASi) and sodium-glucose co-transporter-2 (SGLT2) inhibitors remain foundational, minimizing steroid exposure has become an increasingly important treatment goal. Safety and tolerability concerns continue to drive interest in non-immunosuppressive approaches, particularly for patients facing long-term disease progression and relapse risk.
APOL1 Genetic Testing Expands Precision Medicine in FSGS
Growing adoption of genetic testing—especially for APOL1—is enabling more tailored treatment strategies. A notable share of patients test positive for APOL1, and nephrologists view these individuals as prime candidates for investigational therapies, such as Vertex’s inaxaplin, specifically designed for this population. Physicians report a need for more aggressive, targeted, and non-immunosuppressive options in managing APOL1-positive patients.
Next 12–18 Months Expected to Redefine FSGS Treatment Standards
As multiple agents advance toward regulatory milestones, including a potential FDA decision for Travere Therapeutics’ Filspari in early 2026, the nephrology community is preparing for what could be a much-needed shift in FSGS care. While enthusiasm runs high, nephrologists emphasize that robust clinical evidence—particularly for proteinuria reduction and preservation of estimated glomerular filtration rate (eGFR)—remains the deciding factor for adoption.
As one nephrologist noted, “FSGS needs an FDA-approved targeted therapy that has been clinically shown and proven to actually make a big difference… beyond background therapy.” With several promising therapies on the horizon, the next 12 to 18 months could mark the beginning of a new era in FSGS management—one that finally offers patients and physicians a path beyond symptomatic control toward meaningful, disease-modifying outcomes.
Market Dynamix™ is an independent, data-driven service focused on understanding the evolving dynamics of specialty markets poised for disruption. Leveraging quantitative and qualitative research, the service evaluates current treatment approaches, unmet needs, and likely impact of pipeline agents over a three-to-five-year horizon.
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Kari McCarthy, Nephrology Franchise Head Spherix Global Insights 4848794284 kari.mccarthy@spherixglobalinsights.com