With two approved medicines to treat primary immunoglobulin A nephropathy (IgAN) and a third therapy in phase 3 testing, Novartis is on its way to cornering the market for the indication.
On Friday its first drug to hit the market for IgAN, Fabhalta, gained a full blessing from the FDA, with the U.S. regulator converting the drug's accelerated approval into a traditional nod. Fabhalta is now endorsed to slow kidney function decline in adult IgAN patients who are at risk for disease progression.
The original, speedy IgAN approval for the first-in-class factor B complement inhibitor came two years ago to reduce proteinuria.
“Today’s approval reinforces Fabhalta’s role in preserving kidney function by significantly slowing disease progression, an outcome that matters deeply to patients at risk of long-term kidney damage,” Victor Bultó, Novartis’ US president, said in a release.
Backing the approval was data from a phase 3 placebo-controlled trial that showed statistically significant and clinically meaningful improvement in estimated glomerular filtration rate (eGFR) over two years on Novartis' drug. When done over time, an eGFR blood test can assess kidney functioning and the progress of an IgAN patient.
Fabhalta’s first approval in the indication was based on surrogate endpoint data from the same trial, which measured the reduction in patients’ proteinuria (protein in the urine) at nine months versus placebo. That endpoint is an “increasingly recognized surrogate marker correlating with progression to kidney failure,” Novartis said at the time of that readout.
Autoimmune kidney disease IgAN is diagnosed in roughly 25 per million people worldwide. Up to 50% of IgAN patients with proteinuria progress to kidney failure within 10 to 20 years of diagnosis, often requiring dialysis and/or kidney transplantation, Novartis said.
“The ability to significantly slow kidney function decline is a critical treatment goal,” Dana Rizk, M.D., of the Division of Nephrology at the University of Alabama at Birmingham, said in a release. “This approval of Fabhalta reinforces the importance of targeting underlying disease mechanisms, including complement activation, in treating IgAN to help preserve kidney health.”
In addition to Fabhalta, Novartis gained an FDA accelerated approval last year for another of its oral medicines Vanrafia, which it picked up in a $3.2 billion buyout of Chinook Therapeutics in 2023. Early this year, the Swiss company said it would seek full approval for the endothelin A (ETA) receptor antagonist, even though it came up short in a phase 3 study assessing kidney function improvement.
Novartis is testing its anti-APRIL antibody zigakibart in a phase 3 IgAN study, too. The company amended the trial’s protocol to focus on eGFR and potentially gain a full approval. An interim eGFR readout is expected in the first half of next year.
Also on the IgAN treatment landscape are Travere Therapeutics with Filspari, which gained a full approval in the indication in 2024, and Calliditas Therapeutics’ Tarpeyo, which was cleared a year earlier, becoming the first drug to treat the disorder in the U.S. In 2024, Japanese chemical giant Asahi Kasei acquired Sweden-based Calliditas for $1.1 billion.
Last year, sales of Fabhalta reached $505 million, which were up 291%. In the first quarter of this year, Novartis reported sales of Fabhalta at $169 million, while Vanrafia chipped in an additional $16 million. Fabhalta originally reached the market in 2023 for paroxysmal nocturnal hemoglobinuria (PNH). Last year, Novartis tacked on an FDA nod for Fabhalta to treat C3 glomerulopathy, as well.