Travere Therapeutics (NASDAQ:TVTX) is pursuing growth through expanded use of FILSPARI in rare kidney diseases while advancing a late-stage treatment candidate for classical homocystinuria and building its renal pipeline through the recently in-licensed BTK inhibitor civorebrutinib, Chief Financial Officer Chris Cline said at a Canaccord Genuity discussion.
Cline said the commercial-stage biotechnology company is exclusively focused on rare diseases and has organized its strategy around four pillars: continued FILSPARI growth in IgA nephropathy, the newly approved FSGS indication for FILSPARI, the Phase III development of pegtibatinase in classical homocystinuria, and development of civorebrutinib across multiple rare kidney conditions.
FILSPARI Launch in FSGS Exceeds Expectations
Cline said early FSGS demand has exceeded the company’s expectations, particularly due to the breadth of prescribing physicians. He said Travere’s commercial team was prepared for the launch and was able to apply experience gained from marketing FILSPARI in IgA nephropathy, where there is significant overlap among treating physicians.
“What we saw did exceed our expectations,” Cline said. “I think the most notable aspect of that is the breadth of demand that we’ve seen.”
The company has not seen evidence that the initial FSGS demand reflects drug warehousing or a short-lived bolus of prescriptions, Cline said. Rather, he pointed to a potential market of more than 30,000 identified patients who are biopsy-confirmed, under physician care and consistent with FILSPARI’s label.
Cline said the opportunity could expand as patients move out of an active nephrotic state and become eligible for treatment, and as the availability of an approved therapy encourages more diagnosis and earlier biopsy confirmation.
IgA Nephropathy Demand Continues
In IgA nephropathy, Cline said FILSPARI has maintained its position as the most prescribed medicine in the market. Travere previously reported more than 900 patient start forms for the indication in each of the last two quarters for which it separately disclosed the metric, he said, and the company reported sequential growth in IgA nephropathy during its second-quarter call.
Travere has said FILSPARI could potentially reach more than 100,000 patients across its indications, including more than 70,000 patients with IgA nephropathy and more than 30,000 with FSGS. The company has estimated a peak sales opportunity of more than $3 billion for the product.
The company also received a Notice of Allowance in June for a method-of-use patent relating to certain uses of FILSPARI in IgA nephropathy. Cline said Travere expects the patent to be granted and Orange Book-listed, with an anticipated expiration in October 2037. A similar patent application for FSGS remains under review by the U.S. Patent and Trademark Office, though Cline said the process does not have a fixed timeline.
As more treatments enter the IgA nephropathy market, Cline said Travere expects FILSPARI to remain foundational and increasingly be used in combination regimens. He cited KDIGO guidelines, which he said call for addressing both kidney and immune-system overactivation and targeting proteinuria levels of 0.3 grams or 0.5 grams.
Cline said physicians are already using FILSPARI alongside SGLT2 inhibitors, newer APRIL-directed therapies, TARPEYO and other steroids in some commercial settings. He said newer APRIL-class medicines were studied on top of standard-of-care RAS therapy, which Travere views as the role FILSPARI is positioned to replace.
Late-Stage HCU Program Targets Second-Half Readout
Travere’s Phase III HARMONY study of pegtibatinase is actively enrolling patients with classical homocystinuria, or HCU. Cline described pegtibatinase as potentially the first and only disease-modifying treatment for the disorder, which he said has limited available treatment options.
The company estimates that HCU affects roughly 7,000 to 10,000 patients in the U.S. and a similar number in Europe, although Cline said about half of the populations are currently addressable because diagnosis remains limited. He said newborn screening can measure methionine, but levels are not always elevated at birth, causing some patients to be missed.
Travere expects HARMONY data in the second half of next year. In the earlier Phase I/II COMPOSE study, Cline said the highest-dose cohort showed an approximately 67% reduction from baseline in total homocysteine and brought all patients below 100 µmol.
The company hopes to replicate or approach those results in HARMONY, Cline said, as physicians seek to reduce total homocysteine levels below 100 µmol or 50 µmol to help avoid outcomes including cognitive decline, lens dislocation, osteoporosis and stroke.
Civorebrutinib Adds Renal Pipeline Opportunities
Travere recently licensed civorebrutinib, a next-generation BTK inhibitor, which Cline said could address immune-mediated components of kidney disease and complement FILSPARI’s focus on kidney overactivation.
The company has identified three initial potential indications for the candidate:
- Primary membranous nephropathy, or PMN
- Immune-mediated FSGS
- Minimal change disease
Cline said the three conditions represent a combined prevalent population of about 130,000 patients. He said there are currently no approved treatments for PMN or minimal change disease, while FILSPARI is approved for FSGS and civorebrutinib could target the immune-mediated component of that disease.
Travere plans to apply its clinical, regulatory and commercial infrastructure from FILSPARI to civorebrutinib’s development. Cline said the company will continue to selectively evaluate additional pipeline opportunities in rare renal and rare metabolic diseases.
About Travere Therapeutics (NASDAQ:TVTX)
Travere Therapeutics, Inc (NASDAQ: TVTX) is a biopharmaceutical company headquartered in San Diego, California, dedicated to the development and commercialization of therapies for rare kidney and genetic disorders. The company’s mission is to address unmet needs in conditions with limited treatment options by focusing on diseases that affect small patient populations. Travere combines research, development and commercial capabilities to bring innovative medicines to market.
The company’s lead product is sparsentan, a dual endothelin angiotensin receptor antagonist that has received accelerated approval from the U.S.
