Empaveli, the kidney disease drug from Apellis Pharmaceuticals and Sobi, reported a Phase 3 trial success that could help the treatment keep pace with a competing therapy from Novartis.
On Thursday, the companies said the drug, when added to background therapy, spurred a 68% reduction in urine protein levels compared to placebo in patients with C3 glomerulopathy (C3G) or primary immune complex membranoproliferative glomerulonephritis (IC-MPG).
C3G and IC-MPG are rare kidney diseases that, untreated, harm the kidneys’ filtering ability and lead to the loss of organ function in under a decade. High levels of protein in the urine are a sign of kidney damage or loss of function. Apellis said the diseases affect roughly 5,000 patients in the US and up to 8,000 patients in Europe.
The results at week 26 were statistically significant, meeting the primary endpoint of the study. Apellis said the drug also succeeded on secondary endpoints including a composite of urine protein reduction and estimated glomerular filtration rate (eGFR) stabilization. Standalone changes to eGFR were not reported.
The companies plan to take the data to US and European regulators to get a label expansion for Empaveli, which is currently approved to treat another rare kidney disease, paroxysmal nocturnal hemoglobinuria.
The new data came less than a day after Novartis snagged accelerated approval for its rival drug, Fabhalta, to treat high proteinuria levels in patients with primary IgA nephropathy, another kidney disease. The Swiss pharma is also testing the drug in adult and pediatric patients with C3G, and reported in May that the drug spurred a 35.1% reduction in proteinuria levels in adult patients.
One difference between the two drugs is that Empaveli is delivered subcutaneously while Fabhalta is an oral pill. Andrew Bomback, the Phase 3 study’s primary investigator and a nephrologist at Columbia University, relayed to investors Thursday that the improvement in efficacy will likely keep Empaveli competitive.
“If these data hold out, most people will be inclined to choose the one that has the greater proteinuria reduction, all things being equal,” he said.
Pegcetacoplan, the same compound behind Empaveli, is also approved in the US to treat geographic atrophy via an injection into the eye. Apellis has had a harder time reaching the European market after regulators there did not recommend its use in June. The application for Syfovre is being re-examined by the Committee for Medicinal Products for Human Use and a final decision is expected in the fourth quarter.
Apellis reported $179.1 million in total US sales in the second quarter, the vast majority of which came from treating geographic atrophy. Empaveli earned $24.5 million, and Sobi holds commercial rights outside of the US. Fabhalta earned $22 million in the second quarter.