IgAN or primary immunoglobulin A neuropathy is an autoimmune disease that occurs when clumps of antibodies are deposited in your kidneys, causing inflammation and kidney damage.
Tarpeyo was first approved in December 2021 under accelerated approval, based on the surrogate marker of proteinuria. Marking a significant milestone, it is now the first fully FDA-approved treatment for IgAN based on a measure of kidney function.
Tarpeyo is now approved with a confirmed and statistically significant benefit over placebo in estimated glomerular filtration rate (eGFR) over the two-year period that consisted of 9 months of treatment with Tarpeyo plus optimized renin-angiotensin system inhibitor (RASi) or placebo and optimized RASi and 15 months of follow-up off study drug.
The treatment is a B-cell immunomodulator designed to target a source of the disease and reduce the production of pathogenic galactose-deficient IgA1 antibodies, which cause IgAN.
The company says significant proteinuria reduction was achieved with Tarpeyo plus RASi at 9 months was durable and maintained throughout the 15-month off-drug period.
The FDA approval is for adults with primary IgAN who are at risk of disease progression, irrespective of proteinuria levels.
“The evidence of sustained reductions in proteinuria and a clinically significant reduction in the loss of eGFR, which can help slow the progression towards dialysis or transplant care, highlights the potential of Tarpeyo as a disease-modifying agent in IgAN,” said Richard Lafayette, medical director, Stanford Healthcare.
“Tarpeyo provides physicians and patients an effective treatment option to help improve disease outcomes.”
The approval is based on data from the company’s phase 3 NefIgArd clinical trial, a randomized, double-blind, multicenter, study that assessed the efficacy and safety of Tarpeyo dosed at 16 mg once daily versus placebo on a background of optimized RASi therapy in adult patients with primary IgAN.
IgAN patients access to treatment
“We are thrilled that adult IgAN patients at risk for progression in the United States can now have access to this pioneering treatment option that could help preserve their kidney function and, hence, impact the progression of their disease,” said Renee Aguiar-Lucander, CEO of Calliditas.
“This medicine was specifically developed to target an underlying cause of IgAN, and I would like to express my gratitude to the Calliditas team, study investigators, and most importantly, the patients and caregivers who made this significant milestone possible. I am incredibly proud of the team’s unwavering commitment to the goal of preventing end-stage renal disease in patients with this challenging rare disease.”
Critical step in battle against IgAN
Tarpeyo was generally well-tolerated in the phase 3 NefIgArd clinical trial. The most common adverse reactions in this study were peripheral edema, hypertension, muscle spasms, acne, headache, URT infection, face edema, weight increase, dyspepsia, dermatitis, arthralgia, and white blood cell count increased.
“This first-ever IgAN treatment to get full approval based on kidney function represents a beacon of hope for the entire IgA nephropathy community and signifies a critical step forward in the battle against IgAN,” said Bonnie Schneider, director, and co-founder of the IgAN Foundation.
“The foundation is elated and personally this is so rewarding and validating after a nearly 20-year journey since founding this volunteer-run organization to raise awareness and promote research for IgAN.”