Regeneron Pharmaceuticals operates a fully integrated biotechnology business model that combines proprietary drug discovery platforms, internal manufacturing capabilities, and a hybrid commercialization strategy that relies on both direct U.S. product sales and international profit-sharing collaborations to generate $14.3 billion in annual revenue. The company's revenue architecture is fundamentally bifurcated between products that Regeneron sells directly in the United States and antibody therapies that are commercialized globally through strategic partnerships, creating a complex financial structure where collaboration revenue accounts for approximately 42% of total sales while direct U.S. net product sales contribute the remaining 58%. The EYLEA franchise, comprising both the original aflibercept 2mg formulation approved in 2011 and the high-dose EYLEA HD 8mg formulation approved in August 2023, represents the company's largest direct revenue stream, generating $5.97 billion in U.S. net product sales during fiscal year 2024, which constituted 42% of total company revenues. EYLEA HD, designed to extend dosing intervals from every 8 weeks to every 12 or 16 weeks for patients with neovascular age-related macular degeneration and diabetic macular edema, captured $1.2 billion in U.S. sales during its first full year on the market in 2024, representing a 20% share of the combined EYLEA franchise, while the original EYLEA formulation contributed the remaining $4.77 billion. Outside the United States, Bayer Healthcare records all net product sales of EYLEA and EYLEA HD, with Regeneron receiving a 39% share of profits, which translated to $1.4 billion in collaboration revenue for 2024, a figure that declined slightly from $1.49 billion in 2023 due to currency fluctuations and competitive dynamics in key European and Japanese markets. The Dupixent collaboration with Sanofi represents the second pillar of Regeneron's revenue model and, by global sales volume, the largest therapeutic franchise, with the IL-4Rα-blocking monoclonal antibody generating $14.15 billion in worldwide net product sales during 2024, a 22% increase over the $11.59 billion recorded in 2023. Under the terms of the amended Antibody License and Collaboration Agreement, Sanofi records all global Dupixent sales and bears the commercialization costs, while Regeneron receives a profit share that increased to 27% in 2024, up from 26% in 2023 and 23% in 2022, reflecting the growing profitability of the franchise as manufacturing scale and pricing power improved across dermatology, asthma, chronic rhinosinusitis with nasal polyps, eosinophilic esophagitis, prurigo nodularis, and chronic obstructive pulmonary disease indications. This 27% profit share generated $3.92 billion in collaboration revenue for Regeneron in 2024, while an additional $607.9 million came from reimbursement for manufacturing commercial supplies of Dupixent and Kevzara, bringing total Sanofi collaboration revenue to $4.53 billion. The Kevzara IL-6 receptor antagonist for rheumatoid arthritis and the Praluent PCSK9 inhibitor for hypercholesterolemia, both developed under the Sanofi collaboration umbrella, contributed smaller but still meaningful amounts, with Kevzara generating $458.7 million in global sales and Praluent reaching $765 million in 2024, though Praluent faces significant competitive and reimbursement headwinds from Amgen's Repatha. Libtayo, the PD-1 inhibitor for cutaneous squamous cell carcinoma that Regeneron reclaimed full worldwide rights to from Sanofi in 2022, generated $1.22 billion in global net sales during 2024, with U.S. sales of $787.3 million growing 46% year-over-year as the drug expanded into first-line non-small cell lung cancer and basal cell carcinoma indications. Regeneron's direct commercial operations in the United States sell products primarily to wholesalers and specialty distributors, with Besse Medical and McKesson Corporation collectively accounting for 74% of gross product revenue in 2024, a concentration that creates working capital and credit risk but reflects the consolidated nature of U.S. pharmaceutical distribution. The company's manufacturing model has historically relied on internal production at its Rensselaer, New York and Limerick, Ireland facilities, but the $9 billion infrastructure commitment announced in recent years includes expanding internal capacity and partnering with FUJIFILM Diosynth Biotechnologies through a $3 billion agreement to ensure sufficient supply for Dupixent, EYLEA HD, and pipeline candidates. Research and development spending reached $5.9 billion in 2025, representing 41% of revenue, a ratio that sustains the pipeline of nearly 50 clinical candidates while compressing near-term margins. The company's revenue recognition practices involve recording product sales net of provisions for rebates, chargebacks, discounts, and distribution fees, with the 2024 10-K revealing that sales-related deductions reduced gross product sales by a substantial percentage, though the exact net-to-gross adjustment varies by product and payer mix. Collaboration revenue is recognized based on profit-sharing calculations that depend on Sanofi and Bayer's reported sales, cost of goods sold, and agreed-upon development expense reimbursements, creating quarterly volatility that is partially smoothed by annual true-ups. The company's business model is therefore uniquely exposed to the commercial decisions of its partners: Sanofi's pricing strategy for Dupixent in Europe, Bayer's marketing investment for EYLEA in Japan, and the manufacturing efficiency achieved at shared facilities all directly impact Regeneron's reported revenue and operating income. This hybrid model has enabled Regeneron to achieve profitability while maintaining scientific independence, but it also means that approximately $5.9 billion of annual revenue—roughly 42% of the total—flows through collaboration accounting rather than direct customer invoices, creating transparency challenges and partner dependency risks that are uncommon among U.S. biotech companies of comparable scale.