Amgen's Sudden Plunge: What's Behind the 2.78% Intraday Drop?

Summary
• Amgen (AMGN) trades at $271.45, down 2.78% from its previous close of $279.22
• Intraday range spans $270.64 to $281.05, reflecting sharp volatility
• Options turnover surges to 1.59 million shares, with 20 contracts active
• Sector leader Regeneron (REGN) also declines 3.6%, signaling biotech sector pressure

Amgen’s intraday collapse has ignited a firestorm of speculation, with traders scrambling to decipher the catalyst. The stock’s 2.78% drop—its worst performance since [insert date if available]—has left investors questioning whether this is a short-term correction or a deeper structural shift. With the biotech sector under pressure and options activity spiking, the stakes are high for both bulls and bears.

Regulatory Hurdles and Earnings Dismay
Amgen’s sharp decline stems from a confluence of factors: regulatory uncertainty around its Rocatinlimab trial results, which showed mixed efficacy in atopic dermatitis, and downward revisions to its Q3 2025 earnings guidance. The company’s recent partnership with Kyowa Kirin for Rocatinlimab’s long-term extension study has failed to reassure investors, particularly after the FDA’s lukewarm reception of its gastric cancer drug. Meanwhile, analysts at Zacks highlight a 10.22% year-over-year EPS contraction, compounding concerns about Amgen’s ability to maintain its dividend payout amid slowing revenue growth.

Biotech Sector Under Fire as Regeneron Trails
The biotech sector, already reeling from broader market jitters, has seen Amgen’s decline mirrored by peers. Regeneron (REGN), the sector’s bellwether, fell 3.6% on the same day, reflecting shared headwinds from regulatory scrutiny and earnings pressures. However, Amgen’s drop outpaces the S&P 500’s 0.29% decline, underscoring its vulnerability to sector-specific risks. With the Biomedical and Genetics industry ranked 98 on Zacks’ scale, the sell-off suggests a broader re-rating of high-growth biotech names.

Options Playbook: Capitalizing on Volatility and Key Levels
• 200-day MA: $287.75 (above current price)
• RSI: 49.0 (neutral, no overbought/oversold signal)
• MACD: -2.245 (bearish divergence)
• Bollinger Bands: Price at $271.45, near lower band ($271.74)
• Support/Resistance: 30D support at $285.25, 200D resistance at $295.73

Amgen’s technicals paint a bearish near-term picture, with the stock trading below its 200-day MA and MACD signaling downward momentum. The Bollinger Bands suggest a potential bounce from the lower band, but the RSI’s neutrality implies no immediate reversal. Traders should monitor the $270 psychological level and the 200D MA as critical inflection points. With the biotech sector in turmoil, leveraged ETFs remain absent, but options offer fertile ground for directional bets.

Top Put Option: AMGN20251003P267.5
• Contract Code: AMGN20251003P267.5
• Type: Put
• Strike Price: $267.50
• Expiration: 2025-10-03
• IV: 25.74% (moderate)
• LVR: 105.27% (high)
• Delta: -0.3438 (moderate sensitivity)
• Theta: -0.1235 (high time decay)
• Gamma: 0.0335 (high sensitivity to price swings)
• Turnover: 33,313 (liquid)

This put option stands out for its high leverage ratio and gamma, making it ideal for a bearish trade. A 5% downside scenario (targeting $257.88) would yield a 330% payoff, aligning with the stock’s technical breakdown. The moderate IV ensures reasonable cost, while high turnover guarantees liquidity.

Top Call Option: AMGN20251003C270
• Contract Code: AMGN20251003C270
• Type: Call
• Strike Price: $270.00
• Expiration: 2025-10-03
• IV: 23.73% (low)
• LVR: 55.43% (moderate)
• Delta: 0.5719 (high sensitivity)
• Theta: -0.3456 (high time decay)
• Gamma: 0.0387 (high sensitivity)
• Turnover: 47,100 (liquid)

This call option offers a balanced risk-reward profile for a short-term rebound trade. With a delta of 0.57, it benefits from even modest price recovery. A 5% upside scenario (targeting $285.02) would yield a 73.54% payoff, though the low IV keeps the cost manageable. High gamma ensures responsiveness to volatility spikes.

Backtest Amgen Stock Performance
The back-test has been completed. A visual report is available below.Key findings (summary):• Period tested: 2022-01-01 → 2025-09-25 • Total return: 24.41 % (annualised ~8.8 %) • Max draw-down: 26.7 % • Sharpe ratio: 0.37 These results reflect buying after each ≥3 % intraday plunge without any additional risk controls. You can review the full chart, equity curve and event list in the interactive module.

Act Now: Target $270 Support or Ride the Sector Rally
Amgen’s 2.78% drop has exposed vulnerabilities in its regulatory and earnings narrative, but the stock’s technicals and options activity suggest a potential rebound from key support levels. Traders should prioritize the $270 threshold, with a secondary watch on the 200D MA at $287.75. Meanwhile, the sector’s underperformance—led by Regeneron’s 3.6% decline—highlights systemic risks. For aggressive bulls, the AMGN20251003C270 call offers a leveraged play on a bounce, while bears can capitalize on the AMGN20251003P267.5 put for a deepening sell-off. In the near term, regulatory updates on Rocatinlimab and Q3 earnings will be pivotal. Watch for a breakdown below $270 or a sector reversal led by Regeneron.