Pfizer Inc. (PFE) presented Phase 2 data for its eczema antibody tilrekimig on the same day Florida's attorney general sued the company over its COVID-19 vaccine. The simultaneous developments present investors with a complex mix of potential legal liability and clinical progress, though the immediate market reaction was modest.
Shares closed down 1.40% at $28.12, while the S&P 500 rose 0.19%. The decline trimmed approximately $2.3 billion from Pfizer's market value, a move that cannot be attributed to either event alone. The company's third-quarter report, due November 3, is expected to provide clearer direction for the stock than either headline.
The legal action, filed in St. Lucie County circuit court under Florida's Deceptive and Unfair Trade Practices Act, alleges Pfizer misled consumers by calling the vaccine safe without disclosing risks such as heart inflammation. The state seeks an injunction, penalties per violation, and the return of profits from more than $80 billion in vaccine sales. Pfizer stated the allegations have no merit and described its vaccine statements as accurate and science-based. Similar litigation in Texas was dismissed in December 2024 under the PREP Act, a federal liability shield, though it is not yet known if that defense applies to Florida's state-court claims.
The financial impact of the lawsuit is difficult to size because penalties are counted per violation. However, the conduct Florida challenges concerns a franchise that is already shrinking. Alexandre de Germay, Pfizer's EVP and Chief International Commercial Officer, noted that COVID-19 revenue fell from $11 billion in 2024 to about $6.7 billion in 2025, with a guide of $4 billion for 2026. That 2026 projection represents roughly 6.5% of the company's about $61.5 billion revenue guidance midpoint.
On the clinical front, data from the EADV Congress showed that tilrekimig outperformed placebo in biologic-naive adults. Monthly doses of 400 mg, 200 mg, and 50 mg produced week-16 EASI-75 responses in 58.5%, 61.0%, and 47.8% of patients, respectively, compared to 9.1% on placebo. This metric signifies a substantial reduction in symptom severity for the majority of treated patients. No serious adverse events linked to the treatment were reported in the data presented.
Tilrekimig will be tested against dupilumab, an eczema drug jointly developed by Sanofi (SAN) and Regeneron (REGN), in Phase 3 studies. Since Pfizer already markets the oral eczema drug Cibinqo, tilrekimig would extend an existing franchise rather than create a new one.
Analysts have lifted 2026 revenue estimates to near the top of Pfizer's guidance range, while trimming long-term forecasts for 2029 and 2030 by about 2%. The key metric for investors is growth excluding Comirnaty and Paxlovid, which ran at 5% operationally in the second quarter. If that growth rate holds while COVID-19 revenue declines as expected, the business fundamentals may overshadow the legal proceedings.