The Apellis lawsuit picture has three parts: a securities fraud class action that was dismissed in March 2025 and is now on appeal to the First Circuit, product-liability suits from patients who lost vision after Syfovre injections, and a shareholder case filed in April 2026 challenging disclosures around Biogen’s $5.6 billion acquisition of the company.
Why Apellis Is Being Sued
Syfovre (pegcetacoplan) became the first FDA-approved treatment for geographic atrophy on February 17, 2023.1AHDB Online. FDA Approval of Syfovre and Izervay Reshapes Management of GA2Apellis Pharmaceuticals. Apellis Provides Update on Review of Rare Safety Events With Syfovre3Apellis Pharmaceuticals. Syfovre Safety Update Letter to US ECPs
Apellis initially identified structural variations in 19-gauge filter needles included in some injection kits and voluntarily recalled those kits, though it said a causal link “has not been established.”3Apellis Pharmaceuticals. Syfovre Safety Update Letter to US ECPs In December 2024, the FDA updated Syfovre’s prescribing label to add a dedicated warning about retinal vasculitis and retinal vascular occlusion, noting these events may occur after the first dose and may result in severe vision loss.4FDA. Syfovre Prescribing Information
The Securities Fraud Class Action
The safety disclosures triggered a sharp stock slide across two weeks in July 2023, with shares falling from a pre-disclosure level in the $80s to close at $25.75 on July 31 after Apellis confirmed a seventh case and disclosed a possible eighth.5Glancy Prongay & Murray LLP. Apellis Pharmaceuticals Class Action
A securities fraud class action was filed on August 2, 2023, in the District of Delaware on behalf of investors who bought Apellis stock between January 28, 2021, and July 28, 2023.6Stanford Law School Securities Class Action Clearinghouse. Apellis Pharmaceuticals, Inc. Securities Litigation The complaint named Apellis, CEO Dr. Cedric Francois, CFO Timothy Sullivan, and former Chief Medical Officer Federico Grossi as defendants. Ray Peleckas and the Michigan Laborers’ Pension Fund were appointed lead plaintiffs in October 2023.7Justia. Peleckas v. Apellis Pharmaceuticals, Memorandum and Order
What the Investors Alleged
The amended complaint, filed in February 2024, alleged violations of Section 10(b) of the Securities Exchange Act and SEC Rule 10b-5, plus a Section 20(a) control-person claim against Francois. Plaintiffs conceded Apellis truthfully told investors no retinal vasculitis had been observed in the OAKS and DERBY Phase 3 trials, but argued those statements were misleading because Apellis had not disclosed how infrequently it used fluorescein angiography — the main tool for detecting the condition — during the trials. The complaint contended the trial protocol was inadequate to catch vasculitis because it did not require angiography for patients who dropped out or who developed intraocular inflammation or ischemic optic neuropathy.7Justia. Peleckas v. Apellis Pharmaceuticals, Memorandum and Order
Dismissal and Appeal
The case was transferred to the District of Massachusetts in May 2024 and assigned to Judge Julia E. Kobick. On March 17, 2025, Judge Kobick dismissed the amended complaint with prejudice and without leave to amend.8GovInfo. Apellis Pharmaceuticals Securities Litigation – Memorandum and Order The court found the defendants’ statements were not actionable “half-truths” because the trial protocol, including its angiography frequency, was publicly available on ClinicalTrials.gov and had been incorporated into investor presentations. The court characterized the challenge to the trial methodology as a “scientific disagreement” rather than a basis for securities fraud, noting the FDA had approved the protocol, and it ruled the complaint failed to adequately plead scienter.7Justia. Peleckas v. Apellis Pharmaceuticals, Memorandum and Order
The lead plaintiffs filed a notice of appeal on April 16, 2025, to the U.S. Court of Appeals for the First Circuit under docket number 25-1383.6Stanford Law School Securities Class Action Clearinghouse. Apellis Pharmaceuticals, Inc. Securities Litigation Oral arguments were heard on January 6, 2026, and the appeal remains pending.9Kessler Topaz Meltzer & Check LLP. Apellis Pharmaceuticals Securities Litigation Apellis has argued the investors “reframed” their claims on appeal but that the case still amounts to a scientific disagreement over trial design.10Bloomberg Law. Apellis Says Investors Reframed Appeal, Still Scientific Spat
Product-Liability Suits by Injured Patients
Separately from the investor case, Apellis has faced product-liability litigation from patients who suffered vision loss after Syfovre injections. One active case is Lyday v. Apellis Pharmaceuticals, pending in the Northern District of Texas. Tricia Lyday alleges she suffered a retinal vasculitis reaction after a Syfovre injection in September 2023 that caused permanent blindness in both eyes and required surgical removal of her left eye. Her projected future medical and attendant care costs exceed $5 million, according to court filings.11Dunn Sheehan LLP. Memorandum and Brief in Support of Plaintiffs Second Motion to Compel Discovery – Lyday v. Apellis
The Lyday complaint alleges that Apellis marketed Syfovre for off-label uses and pursued what the plaintiffs call a “delay and obfuscation strategy” regarding known vasculitis risks. According to the plaintiffs’ brief, the FDA instructed Apellis to update the Syfovre label to warn of vasculitis at least five times before the company made the change in November 2023. The filing also alleges that CEO Cedric Francois sold 150,000 shares of Apellis stock for $6.2 million on August 30, 2023, two business days after a meeting at which the FDA rejected the company’s theory that faulty needles caused the vasculitis events. The case remains in active litigation with expert designation deadlines set for late 2025.11Dunn Sheehan LLP. Memorandum and Brief in Support of Plaintiffs Second Motion to Compel Discovery – Lyday v. Apellis
The Lyday filing further states that European regulators rejected Apellis’s application to market Syfovre three times between September 2023 and June 2026, citing safety concerns and the drug’s propensity to cause vasculitis.11Dunn Sheehan LLP. Memorandum and Brief in Support of Plaintiffs Second Motion to Compel Discovery – Lyday v. Apellis
Shareholder Challenge to the Biogen Deal
On March 31, 2026, Biogen announced it would acquire Apellis for $41.00 per share in cash plus a non-transferable contingent value right worth up to $4.00 per share tied to Syfovre sales milestones, valuing the upfront equity consideration at approximately $5.6 billion.12Apellis Pharmaceuticals. Biogen to Acquire Apellis, Enhancing Company’s Growth Portfolio Biogen completed the acquisition on May 14, 2026, after approximately 82.4% of outstanding shares were tendered.13Biogen. Biogen Completes Acquisition of Apellis Pharmaceuticals
On April 27, 2026, an Apellis stockholder named Elissa Schwartz filed suit in Massachusetts Superior Court challenging the merger disclosures. Schwartz v. Chan et al. named Apellis, its directors, Biogen, and the acquisition subsidiary as defendants. The complaint alleged the proxy filings misrepresented or omitted material information and asserted claims for negligent misrepresentation and general negligence under Massachusetts common law.14Biogen. Biogen SC 14D-9/A Filing – Litigation Disclosure The lawsuit did not prevent the deal from closing.