An established sales force and payer authorization criteria will fuel a fast launch for Travere Therapeutics’ Filspari in its new indication and power the franchise to peak sales of $3.1 billion, Guggenheim Securities analysts predicted in a note to investors.
Travere won FDA approval for the drug in focal segmental glomerulosclerosis (FSGS) earlier this month. Sales of Filspari in its first indication, IgA nephropathy (IgAN), have grown gradually since Travere won approval in the setting three years ago, climbing to $322 million last year. Guggenheim analysts expect Filspari to make a more explosive start in the rare kidney disease FSGS.
The FSGS launch “begins from a materially warmer starting point” than the IgAN rollout, the analysts said. Travere’s nephrology sales force has three years of experience calling on an IgAN prescriber base that largely overlaps with their FSGS prospects.
Peter Heerma, chief commercial officer at Travere, said on a call with investors this month that the sales team previously focused on 6,000 U.S. nephrologists who cover about 90% of IgAN patients. Travere expanded its sales team late last year, adding reps to target pediatric nephrologists who treat people with FSGS.
Guggenheim analysts expect physicians to be receptive to the new drug because FSGS carries higher clinical urgency than IgAN. Nephrologists managing more symptomatic and rapidly progressing patients should be more likely to get patients on a new drug as soon as possible than those treating people with less urgent conditions.
With launch foundations in place, Guggenheim analysts predict Filspari will generate $68 million in net sales from FSGS in its first 8.5 months on the U.S. market. Filspari generated $29 million in net revenue over the 10.5 months following FDA approval for drug in IgAN. Guggenheim analysts said the consensus among their peers is that Filspari will generate $58 million in FSGS in its first 8.5 months on the market.
The gap between expectations at Guggenheim and the wider analyst community widens over time. By 2029, Guggenheim analysts expect Filspari to be approaching blockbuster sales in FSGS, a forecast that is roughly double the consensus of their peers.
Travere’s ability to ramp Filspari sales quickly in FSGS is particularly important because the biotech has a relatively short window of opportunity in the indication. The company aims to extend patent protection for Filspari, but its current intellectual property only covers the drug until 2033. Guggenheim analysts predict sales across FSGS and IgAN will peak above $3 billion in 2032 and fall to below $2 billion in 2033.