More than a year after Apellis Pharmaceuticals proved its C3 inhibitor pegcetacoplan could go head-to-head with industry heavyweight Soliris in patients with the rare blood disorder paroxysmal nocturnal hemoglobinuria (PNH), the biotech is finally getting its shot at the market.
The FDA on Friday approved Apellis' pegcetacoplan, an under-the-skin injection now dubbed Empaveli, to treat adults with PNH. The disease is a rare, chronic blood disorder characterized by the destruction of healthy, oxygen-carrying red blood cells.
The destruction is driven by an uncontrolled immune system and defective bone marrow not making enough blood components. Apellis’ C3 therapy, which targets a different enzyme than Alexion's C5 inhibitors, is designed to regulate that excessive immune response.
Leading up to the FDA's decision, it wasn't clear whether the agency would limit its approval to patients who didn't respond to prior treatments. It didn’t, but Apellis will still kick off Empaveli's launch by focusing on patients with suboptimal responses to C5 inhibitors—namely Soliris and its follow-up Ultomiris—before moving on to the broader patient population, Chief Commercial Officer Adam Townsend said in an interview ahead of the FDA's decision.
“Post-approval, we plan to be out appropriately speaking to PNH patients and the physicians within about two weeks,” he said, declining to comment on the inhibitor’s price tag.
The fledgling biotech has already proven Empaveli can face off against Alexion’s Soliris—and beat it—at least in a clinical trial. In the phase 3 Pegasus study, Empaveli topped Soliris in improving patients' hemoglobin levels at 16 weeks. In the 80-patient study, those in the pegcetacoplan arm had increased hemoglobin levels by 3.8 g/dL over the Soliris group.
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More late-stage trial data for the drug is coming down the pike soon for patients who are treatment-naïve, meaning they haven’t been treated with another inhibitor within three months before the trial start. That study, known as Prince, was designed to hedge Apellis’ full FDA application. The biotech was able to move forward without that trial thanks to the positive results from Pegasus, CEO Cedric Francois said in an interview.
The company is also targeting a handful of new indications for Empaveli and expects phase 3 trial data for geographic atrophy (GA)—an advanced form of age-related macular degeneration (AMD) that leads to progressive and irreversible vision loss—in the third quarter.
“It’s truly, we believe, a platform opportunity to control C3 systemically in the body of patients with a multitude of indications,” Francois said.
Apellis says roughly a third of the approximately 1,500 patients now treated with C5 antibodies in the U.S. don’t respond fully. After the company targets those initial patients, it will expand its outreach “where the unmet need exists," Townsend said.
“Those patients have a low and falling hemoglobin, and they have to continually be transfused and have constant transfusions,” Townsend said. "We have identified where they are, who their physicians are, and we've spent a lot of time with the PNH community through digital engagements."
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Still, Apellis could have an uphill battle on its hands with Soliris and Ultomiris, Alexion’s follow-up C5 antibody that touts a more convenient dosing schedule. Those two drugs together reeled in $5.1 billion in sales last year, the bulk of Alexion’s total revenue. That's not to mention an oral candidate from Novartis, known as LNP023, which could also end up vying for a slice of the PNH market.
Alexion has already caught the attention of one Big Pharma player, however, which could make Apellis’ ambitions even more difficult. AstraZeneca announced late last year that it will dish out $39 billion to acquire Alexion, and that transaction should close in the third quarter this year.
A point that was particularly enticing for AZ and could spell uncertainty for Apellis: Alexion has successfully moved more than 70% of its PNH patients from Soliris to Ultomiris, which gained an FDA nod in late 2018. Sales of that drug climbed 218% in 2020 to $1.08 billion.