Regeneron Plummets 3.7%—What’s Driving the Sell-Off?

• Regeneron (REGN) sinks to $549.26, erasing $3.3B market cap after breaching critical $550 support.
• Q1 earnings miss ($8.22 vs $8.83 estimates) triggered institutional selling, with CenterBook unloading 64% of its stake.
• Biotech sector under pressure: Amgen (AMGN) slips 1.39%, but Regeneron’s decline outpaces peers.
• Traders eye 52-week low ($476.49) as Bollinger Bands tighten, with MACD divergence hinting at exhaustion.

Regeneron’s brutal intraday plunge to a near-year low marks a pivotal test for its technical underpinnings. Shares have shed 11% from their 200-day moving average ($698.81), while institutional outflows and sectorwide Medicare pricing concerns amplify downside risks.

Earnings Miss and Portfolio Liquidation Ignite Selling
Regeneron’s collapse stems directly from its April 29 Q1 earnings miss, where EPS of $8.22 fell short of $8.83 estimates and revenue dropped 3.7% to $3.03B. Institutional investors reacted swiftly: CenterBook Partners slashed holdings by 64.3%, offloading 10,270 shares to reduce its stake to 5,714. This exodus, paired with broader sector rotation out of high-multiple biotechs, fueled the selloff. Analysts now question whether Regeneron’s pipeline can offset looming patent cliffs for Dupixent and EYLEA biosimilar threats, creating existential uncertainty for bulls.

Biotech Sector Mixed as Amgen Leads Weakness
While Regeneron’s decline outpaces the sector, peers like Amgen (AMGN) and Eli Lilly (LLY) face similar headwinds. AMGN’s 1.39% drop reflects Medicare drug-price negotiation fears, but Regeneron’s unique challenges—including $735M in Dupixent sales at risk from 2027 patent expirations—create sharper downside risks. The sector’s 200-day SMA ($618.18) contrasts sharply with Regeneron’s current $549.26, signaling it’s among the hardest-hit names in a consolidating biotech space. However, sector-wide declines don’t fully explain Regeneron’s 12% underperformance vs. peers this month.

Bullish Calls vs Bearish Breaks—Regeneron’s Options Landscape
Technical Indicators:
• 200-day MA: $698.81 (resistance)
• RSI: 85.82 (deep overbought, signaling exhaustion)
• Bollinger Bands: Squeeze between $495 and $572 (break below $550 risks $476 collapse)
• MACD: +6.40 vs Signal Line -0.22 (bullish divergence but fading momentum)

Aggressive traders should focus on call options targeting the $550-$520 zone. Among the most compelling contracts:

REGN20250725C550: Strike $550 | Delta 51.98% | Leverage 47.62%
Why it works: Moderate delta balances risk/reward. A 5% downside to $523 would still allow profit capture near strike price. High turnover (3,786) ensures liquidity.

REGN20250725C555: Strike $555 | Delta 43.40% | Leverage 76.39%
Why it works: Higher leverage amplifies gains if price stabilizes above $550. Gamma of 0.017 ensures sensitivity to volatility spikes. Theta decay (-1.28) demands execution by mid-July.

Action Alert: Fade the bounce—short REGN20250725C550 if $550 breaks, targeting $520 with a stop above $574. Bulls must hold $550 to avoid a freefall to $476.

Backtest Regeneron Stock Performance
The backtest of Regeneron (REGN) after a -4% intraday plunge shows mixed results. While the 3-day win rate is high at 50.91%, the returns over 10 and 30 days are negative at -0.12% and -0.04%, respectively. This suggests that while REGN may bounce back in the short term, long-term returns are not significantly positive following such a plunge.

Hold $550 or Tumble to $476—Regeneron’s Critical Crossroads
Regeneron faces an inflection point: sustained trading below $550 risks a collapse toward its 52-week low ($476.49), while a rebound above $574 could reignite short-covering. Analysts’ $823.54 consensus target remains distant against near-term institutional outflows and patent-related risks. Monitor Amgen’s performance—its 1.39% dip signals sectorwide pressures—as a proxy for biotech sentiment. Traders should prioritize stop-loss discipline: a breakdown below $530 invalidates bullish calls, triggering a shift to puts targeting $520. Final warning: This is a ‘fade the rally’ environment—exit longs if $550 fails. Watch for FDA updates on Dupixent’s expanded uses as the next catalyst.