BIIB vs REGN: Correlation
Biogen (BIIB) and Regeneron Pharmaceuticals (REGN) show a moderate relationship: their 3-year correlation of weekly returns is 0.46.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are BIIB and REGN?
Across a 3-year window, the weekly returns of BIIB and REGN correlate at 0.46, moderate. Recent behaviour matches the longer record: 0.40 over 1 year against 0.46 over 3. Stretching to 5 years gives 0.36, with an annualized covariance of 439.2 %².
By 3-year correlation, REGN places #13 of the 32 assets tracked against BIIB. Correlation aside, the last 12 months split them widely, with BIIB ahead by 24.1 points (+62.4% versus +38.3%). This link changes with the market regime, having swung between 0.02 and 0.61 on a rolling one-year basis.
How is this computed?
Pearson correlation on weekly returns: ρ(A,B) = cov(rA, rB) / (σA · σB), over windows of 52, 156 and 260 weeks. Covariance is annualized (×52) and expressed in %². Full definitions on the methodology page.
BIIB vs REGN: side by side
| BIIB (Biogen) | REGN (Regeneron Pharmaceuticals) | |
|---|---|---|
| 1-year return | +62.4% | +38.3% |
| 5-year return | -35.7% | +20.4% |
| Volatility (ann.) | 30.1% | 31.8% |
| Beta vs S&P 500 | 0.53 | 0.61 |
| Max drawdown (3Y) | -57.7% | -59.7% |
| Market cap | $32.7B | $83.2B |
| P/E (trailing) | 39.2 | 20.2 |
| Dividend yield | 0.00% | 0.45% |
| Sector / category | Health Care | Health Care |
Year-by-year returns
| Year | BIIB | REGN |
|---|---|---|
| 2022 | +15.4% | +14.2% |
| 2023 | -6.6% | +21.7% |
| 2024 | -40.9% | -18.9% |
| 2025 | +15.1% | +9.0% |
| 2026 | +25.9% | +5.0% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are BIIB and REGN good diversifiers for each other?
A fair diversifier. At 0.46, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
FAQ
What is the correlation between BIIB and REGN?
Using weekly returns as of 2026-08-27: 0.46 over 3 years, with 0.40 over the last year and 0.36 over 5 years.
Is REGN a good diversifier for BIIB?
A fair diversifier. At 0.46, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
What does a correlation of 0.46 mean?
On the −1 to +1 scale, 0.46 describes how much the two returns move together: +1 is lockstep, 0 is independence, negative values mean opposite directions. It says nothing about which performed better.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/biib-vs-regn.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/biib-vs-regn/)
The core API is free. Terms and every endpoint in the API documentation.
Related comparisons
Hubs: BIIB correlations · REGN correlations
