Calliditas Therapeutics advances kidney disease drug, meeting primary endpoint in study

15-Aug-2023 - Last updated on 15-Aug-2023 at 13:34 GMT

Calliditas Therapeutics AB’s phase 3 study looking at a cure for a kidney disease called IgA nephropathy (IgAN) has met its primary endpoint and the full data has been published in The Lancet.

The NeflgArd Study with Nefecon (Tarpeyo ((budesonide)) delayed release capsules Kinpeygo) in adults with IgAN met its primary endpoint, an estimated glomerular filtration rate (eGFR), that showed Nefecon demonstrating significant kidney protective effect over placebo.

IgAN is also known as Berger disease, is a kidney disease. It happens when germ-fighting protein immunoglobulin A (IgA) builds up in the kidneys. This causes inflammation that, over time, can make it harder for the kidneys to filter waste from the blood.

End-stage kidney disease

Jonathan Barratt, professor of renal medicine at the University of Leicester said: “IgAN is a severe debilitating disease leading to end-stage kidney disease in more than 50% of the patients. The full results from NefIgArd study demonstrate the ability of Nefecon to slow kidney function deterioration and as such to slow down the disease progression and delay the need for dialysis and kidney transplantation.

“These results also support the key role of the gut immune system in the pathogenesis of IgAN and the differentiated effect of Nefecon treating the disease at its origin.”

The analysis published in The Lancet shows that Nefecon demonstrated a highly statistically significant and clinically relevant benefit compared to placebo in eGFR over the two-year period of 9-months of treatment with Nefecon and 15-months of follow-up off drug.

Calliditas said that after the two-year period, there was a 6.11 mL/min/1.73 m2 decline in eGFR in the Nefecon arm compared with a 12.0 mL/min/1.73 m2 decline in the placebo arm, corresponding to a difference in two-year eGFR total slope of 2.95 mL/min/1.73m2 per year (p<0·0001).

Reduction in UPCR

The reduction in urine protein creatinine ratio (UPCR) observed with Nefecon treatment was durable, reflecting a long-lasting treatment effect during the 15-month follow-up period off treatment.

Patients treated with Nefecon maintained a greater than 30% proteinuria reduction from the end of the 9-month treatment through the entire follow-up period, with a reduction in UPCR of over 50% observed at 12 months.

Nefecon was generally well tolerated, with the majority of treatment-emergent adverse events (TEAE) being mild or moderate, and with TEAEs leading to discontinuation of study drug in less than 10% of patients. Objective measures of mean weight and blood pressure showed non-clinically relevant changes.

“The data demonstrated supportive 2-year total slope analyses that were not only statistically significant but also clinically meaningful, showcasing a sustained treatment benefit. The eGFR benefit was observed across the entire study population, irrespective of baseline urine protein-to-creatinine ratio,” said Richard Lafayette, of Stanford Healthcare and lead author of the publication.

“The sustained reduction of proteinuria and the protective effect on kidney function support the disease-modifying effect of Nefecon. These robust results provide new hope for patients and reinforce Nefecon's potential to make a meaningful difference in the lives of those affected by this challenging disease.”

Reduce proteinuria in adults

Nefecon is currently approved under accelerated approval to reduce proteinuria in adults with Primary IgAN at risk of rapid disease progression, generally a UPCR greater than or equal to 1.5 g/g.

In June 2023, Calliditas submitted a supplemental new drug application (sNDA) to the US Food and Drug Administration (FDA) seeking full approval based on the full NefIgArd study data. Calliditas is supporting its partner STADA Arzneimittel AG with the filing for full approval with the European Commission and The Medicines and Healthcare products Regulatory Agency (UK MHRA) in the second half of this year (2023).

“We are thrilled to see the NefIgArd phase 3 data published in The Lancet, highlighting these important results for the IgAN patient community,” said Renée Aguiar-Lucander, chief executive officer at Calliditas.

“The established long-term eGFR benefit reflects Nefecon’s ability to slow kidney function decline by targeting the origin of the disease and providing a differentiated and disease-modifying treatment alternative.”