Apellis Pharmaceuticals announced a $300 million capped royalty purchase agreement with Sobi that provides significant non-dilutive financing while maintaining the company's U.S. commercialization rights for its rare kidney disease therapy. The transaction underscores both companies' confidence in the growth potential of systemic pegcetacoplan for treating rare kidney diseases.
Under the agreement, Apellis will receive $275 million upfront and up to $25 million in milestone payments upon European Medicines Agency (EMA) approval of Aspaveli for C3 glomerulopathy (C3G) and primary immune complex membranoproliferative glomerulonephritis (IC-MPGN). In exchange, Sobi will acquire 90% of Apellis' future ex-U.S. royalties for the therapy.
"This transaction reflects our shared conviction in the potential of Aspaveli/EMPAVELI to transform the treatment landscape for patients with rare diseases, including C3G and IC-MPGN," said Timothy Sullivan, chief financial officer at Apellis. "The non-dilutive funding from this transaction further strengthens our balance sheet and provides significant operational flexibility as we approach sustainable profitability."
Regulatory Timeline and Market Opportunity
Aspaveli (known as EMPAVELI in the U.S.) is currently approved in the European Union, other countries globally, and the United States for treating paroxysmal nocturnal hemoglobinuria (PNH), a rare blood disorder. The therapy is now under regulatory review in both the EU and U.S. for C3G and IC-MPGN treatment.
An opinion by the EMA's Committee for Medicinal Products for Human Use is expected before year-end, while the U.S. Prescription Drug User Fee Act action date is set for July 28, 2025.
C3G and primary IC-MPGN represent significant unmet medical needs, affecting an estimated 5,000 people in the United States and up to 8,000 in Europe. These rare and debilitating kidney diseases can lead to kidney failure, with approximately 50% of patients suffering kidney failure within five to 10 years of diagnosis, requiring kidney transplant or lifelong dialysis.
Strategic Partnership Structure
The agreement includes defined caps tied to Aspaveli's performance. Sobi retains 90% of ex-U.S. royalties until these caps are achieved, after which 100% of all ex-U.S. royalties revert to Apellis. Under the companies' existing 2020 collaboration agreement, Apellis is eligible for tiered royalties on ex-U.S. sales ranging from high teens to high twenties.
"We are pleased to reaffirm our ongoing partnership with Apellis and share their strong belief in Aspaveli/EMPAVELI's potential to deliver significant long-term growth," said Guido Oelkers, chief executive officer at Sobi. "We are confident in our ability to reach patients with C3G and IC-MPGN globally following regulatory approvals, by leveraging our broad commercial footprint, deep rare disease expertise, and proven success in PNH."
Apellis retains exclusive commercialization rights for systemic pegcetacoplan in the United States, while Sobi maintains exclusive ex-U.S. commercialization rights. The companies continue their global co-development rights for systemic pegcetacoplan, with Sobi's opt-in rights for future development programs remaining unchanged.
Disease Burden and Treatment Challenge
The targeted kidney diseases present substantial clinical challenges. Excessive C3 deposits serve as a key marker of disease activity, leading to kidney inflammation, damage, and failure. Additionally, approximately 90% of patients who previously received a kidney transplant experience disease recurrence, highlighting the persistent nature of these conditions.
The transaction positions both companies to address this significant unmet medical need while providing Apellis with substantial financial flexibility to advance its innovative pipeline and expand the reach of its approved products.
