Regeneron Pharmaceuticals, Inc. (REGN) Stock Price & How to Invest

Regeneron makes money primarily through two large franchises. Dupixent, an anti-inflammatory antibody used for eczema, asthma, COPD, and other conditions, is developed and commercialized in collaboration with Sanofi, and Regeneron records its share through Sanofi collaboration revenue (about $1.6 billion in Q1 2026, up roughly 36%). Eylea and the higher-dose Eylea HD treat retinal diseases such as wet age-related macular degeneration and diabetic eye disease, generating combined U.S. net product sales of about $941 million in Q1 2026, with Eylea HD now roughly half of that mix. Libtayo in oncology and a pipeline of nearly 50 clinical candidates round out the revenue base.

Regeneron was founded in 1988 by Leonard Schleifer, who remains a central leader, with chief scientific officer George Yancopoulos shaping its science-first culture. The company built its reputation on proprietary VelociSuite antibody-discovery technologies and the Regeneron Genetics Center, an internal engine that turns large-scale human genetics into drug targets. That R&D productivity, rather than acquisitions, has historically driven its growth. In 2025 the board initiated its first quarterly dividend and expanded share repurchases, signaling a more mature capital-return posture alongside heavy ongoing R&D investment.

The clearest risk is Eylea biosimilar erosion. Amgen's Pavblu launched in late 2024 and pressured sales, and settlements clear paths for Sandoz, and Alvotech and Teva, to launch competing copies in the U.S. around the fourth quarter of 2026, with erosion expected to accelerate. Eylea HD and Dupixent growth are the offsets, but the timing gap matters. The business is also concentrated in a few franchises, so a single setback in Dupixent or a major pipeline failure would weigh heavily, and the collaboration structure with Sanofi means Regeneron does not control all of its largest product's economics.

A simple financial snapshot. These are approximations and refresh quarterly; for current figures see Regeneron Pharmaceuticals, Inc.'s investor relations page or your broker.

• Total revenue (TTM, approx): ~$14 billion
• Q1 2026 total revenue: ~$3.6 billion (up ~19% YoY)
• Dupixent global net sales (Q1 2026): ~$4.9 billion (up ~31%)
• Eylea + Eylea HD U.S. net sales (Q1 2026): ~$941 million combined
• Cash and marketable securities (approx): ~$17 billion
• P/E (approx): ~15x
• Market capitalization (approx): ~$66 billion

Figures are approximate and tied to the asOf date; verify current numbers with a live quote before acting. Regeneron reported about 19% revenue growth and adjusted EPS of roughly $9.47 in Q1 2026, beating estimates, and authorized an additional $3 billion buyback. The mid-teens P/E reflects the market weighing strong Dupixent growth against expected Eylea biosimilar erosion.

These are the investment theses REGN naturally fits into. Each links to a full theme guide listing every other stock that belongs and the ETFs commonly used as a passive proxy.

Other names that show up alongside REGN in the same themes. Worth a look if you're thinking about diversification within a single thesis rather than concentration on one ticker.

There are three common ways to get REGN exposure. Buy shares (or fractional shares) directly at any major broker. Hold an ETF that includes it, which spreads the position across many companies. Or build it into a focused thematic basket, so REGN sits alongside other stocks that express the same thesis.

Walnut takes the basket route. Describe a thesis where REGN fits (for example “AI infrastructure” or “dividend-growth large-caps”) and the AI proposes 5 to 6 constituents with target weights. You review the plan and fund it through your own broker when you're ready.

Regeneron today is two stories layered on top of each other: a Dupixent-led immunology franchise that grew global net sales roughly 31% to about $4.9 billion in Q1 2026, and a legacy Eylea eye-disease business now facing direct biosimilar competition. The company is broadening into oncology (Libtayo, fianlimab) and other areas while Eylea HD, a higher-dose formulation, defends share. If you believe the pipeline and Dupixent growth can outrun the Eylea decline, the question becomes sizing and overlap with other healthcare holdings you already own, not timing. The risk is that biosimilar erosion accelerates faster than newer products scale.

Whether REGN is worth buying today depends more on your time horizon and what you already hold than on any single call. We walk through valuation, what would have to go right, and the risks in is REGN a buy?, and where the stock could go from here in the REGN stock forecast.

For income investors, whether REGN pays a dividend and how the payout looks is covered in does REGN pay a dividend? And to weigh REGN against a peer, read the full side-by-side comparisons: REGN vs GILD.