Amgen's Aggressive IP Defense and Its Implications for Biosimilar Competition

In the high-stakes arena of biopharmaceutical innovation, Amgen Inc. (NASDAQ: AMGN) has long positioned itself as a fortress of intellectual property (IP) protection. The company's recent settlements with biosimilar manufacturers like Celltrion and ongoing antitrust battles, such as the CareFirst of Maryland, Inc. v. Amgen Inc. case, underscore its strategic commitment to defending its blockbuster drugs. This article examines how Amgen's IP litigation tactics shape its financial resilience, investor confidence, and long-term earnings potential in the face of biosimilar competition.

Strategic IP Defense: A Double-Edged Sword

Amgen's aggressive patent litigation strategy has been a cornerstone of its business model. The January 2025 settlement with Celltrion over denosumab biosimilars-a class of drugs marketed as Prolia and Xgeva-exemplifies this approach. A U.S. court ruled Amgen's patents valid, enforceable, and infringed by Celltrion's biosimilars, allowing the latter to launch as early as June 1, 2025, according to an Amgen update. While this delay buys Amgen time to mitigate revenue erosion, it also signals the inevitability of biosimilar encroachment.

Similarly, the CareFirst case, which alleges Amgen extended its monopoly on etanercept (Enbrel) through strategic patent acquisitions, highlights the regulatory and reputational risks of aggressive IP enforcement. The court's denial of Amgen's motion to dismiss suggests that antitrust scrutiny could intensify, potentially leading to financial penalties or forced licensing agreements, as reported by BigMoleculeWatch.

Financial Resilience Amid Biosimilar Pressures

Despite these challenges, Amgen's financial performance in 2025 has defied expectations. For the quarter ending March 31, 2025, , , , according to BigMoleculeWatch. This outperformance, , reflects the strength of its core products like Repatha and Evenity, as well as cost discipline in R&D, according to TradingView.

However, biosimilar competition looms large. The expiration of patents for Prolia and Xgeva in key markets has already enabled three biosimilars to enter the fray, as noted in Sharewise. Analysts at Cantor Fitzgerald and Wells Fargo have adjusted price targets upward to $315 and $300, respectively, citing Amgen's robust earnings but cautioning that biosimilar pressures could weigh on margins in the medium term, as reported by Investing.com.

Investor Confidence: A Mixed Signal

Investor sentiment toward Amgen remains cautiously optimistic. Institutional investors, including Ausdal Financial Partners and Modern Wealth Management, have significantly increased holdings in 2025, with the latter boosting its position by 171.5% in Q4, as noted in MarketBeat. This activity suggests confidence in Amgen's ability to navigate biosimilar threats through innovation and market education, as CEO emphasized at the J.P. Morgan Healthcare Conference, as reported by KoreaBioMed.

Yet, the stock's performance tells a nuanced story. While Amgen's shares gained 14.4% year-to-date through November 2025, , as reported by Investing.com. Analyst ratings are split, with 's "Overweight" rating ($342 target) contrasting Baird's "Underperform" ($215 target), as reported by Investing.com. This divergence reflects divergent views on whether Amgen's IP strategy can sustain margins or if biosimilar competition will accelerate margin compression, as reported by Investing.com.

Future Outlook: Balancing Innovation and Defense

Amgen's long-term success hinges on its ability to balance IP defense with innovation. The company's diabetes/obesity pipeline and advancements in Repatha's cardiovascular indications offer growth avenues, as reported by TradingView. However, the June 2025 biosimilar launches for Prolia/Xgeva and the unresolved CareFirst case could create near-term headwinds.

For investors, the key question is whether Amgen's litigation-driven revenue protection justifies its premium valuation. While the company's strong cash flow and R&D pipeline provide a buffer, biosimilar erosion of high-margin products like Enbrel and Neulasta could pressure earnings beyond 2025.

Conclusion

Amgen's aggressive IP litigation strategy has bought time but not a permanent solution. The settlements with Celltrion and Sandoz, while delaying biosimilar entry, also highlight the industry's shifting dynamics. Investors must weigh Amgen's short-term financial strength against long-term risks, including antitrust penalties and margin compression. For now, the stock's mixed analyst ratings and institutional buying suggest a market bracing for both opportunities and challenges in the coming years.