The Strategic Implications of Sandoz-Regeneron Patent Settlement for Biosimilar Market Dynamics

The biosimilar market for Regeneron’s Eylea (aflibercept) has become a battleground for patent litigation, regulatory maneuvering, and strategic settlements, reshaping competitive dynamics and investment risks for developers. As of September 2025, the unresolved Sandoz-Regeneron dispute over Enzeevu™, coupled with recent settlements involving Biocon and Amgen, underscores the fragility of market entry for biosimilars and the enduring influence of originator companies in delaying generic competition.

The Sandoz-Regeneron Stalemate: A Case Study in Legal Leverage

Regeneron’s aggressive litigation strategy has delayed Sandoz’s Eylea biosimilar for over a year. Despite FDA approval of Enzeevu™ in August 2024, Sandoz has yet to announce a launch date due to ongoing litigation involving 46 patents [1]. This contrasts sharply with the Biocon settlement in April 2025, which allowed Yesafili™ to secure a 2026 launch window [2]. The disparity highlights how originator companies can exploit patent thickets to extend market exclusivity, even as biosimilars navigate regulatory hurdles.

According to a report by Big Molecule Watch, Regeneron’s litigation tactics have created a “chilling effect” on market entry, with developers facing average delays of 18–24 months post-FDA approval [3]. For Sandoz, the unresolved case represents a dual risk: legal costs and reputational damage from prolonged litigation, compounded by the uncertainty of a delayed launch in a market already saturated with pending biosimilars.

Settlements as Strategic Tools: Lessons from Denosumab and Aflibercept

The Sandoz-Amgen settlement for denosumab biosimilars offers a contrasting model. By agreeing to a May 31, 2025, launch date for Wyost® and Jubbonti®, Sandoz avoided protracted litigation and secured a foothold in a market where Celltrion’s biosimilar followed just one day later [2]. This “coordinated entry” strategy minimized price erosion risks while ensuring market share.

In contrast, the Biocon-Regeneron settlement—though granting a 2026 launch—includes vague clauses about “undisclosed circumstances” that could further delay entry [2]. Such ambiguity reflects the growing trend of originator companies using settlements to extract concessions, such as delayed launches or revenue-sharing agreements, rather than outright exclusivity extensions.

Market Dynamics: Fragmentation and Pricing Pressures

The Eylea biosimilar landscape is now highly fragmented, with six approved products (including Enzeevu™ and Pavblu™) but only one (Amgen’s Pavblu™) commercially active as of Q3 2024 [1]. This fragmentation creates a paradox: while multiple entrants theoretically drive down prices, overlapping litigation and staggered launches prevent meaningful competition.

Data from FiercePharma indicates that Eylea’s U.S. sales remain resilient at $3.2 billion annually, with biosimilars capturing less than 5% market share despite five years of litigation [4]. The delay in market entry has allowed Regeneron to maintain pricing power, even as generic alternatives proliferate. For investors, this underscores the risk of overestimating biosimilar penetration in markets where originator companies retain legal and regulatory leverage.

Investment Risks: Beyond Legal Uncertainty

The Sandoz-Regeneron case highlights three critical risks for biosimilar developers:
1. Prolonged Litigation Costs: Legal battles can drain R&D budgets and delay ROI. Sandoz’s $150 million investment in Enzeevu™, for instance, now faces indefinite deferral [3].
2. Regulatory Scrutiny: The BPCIA’s 20-day information-sharing requirement has become a litigation tool. Regeneron’s claim that Sandoz failed to disclose its aBLA underscores how procedural noncompliance can trigger costly delays [3].
3. Market Saturation: With six Eylea biosimilars approved but only one launched, developers face the risk of oversupply once multiple products enter the market simultaneously.

Conclusion: Navigating the New Normal

The Sandoz-Regeneron dispute exemplifies the evolving playbook of originator companies in the biosimilar era. While settlements like the Biocon agreement offer a path forward, they often come at the cost of delayed market access and reduced pricing flexibility. For investors, the lesson is clear: biosimilar development is no longer a race to FDA approval but a marathon through legal and regulatory labyrinths.

As the Eylea market approaches its inflection point in 2026, developers must prioritize robust IP strategies, early regulatory engagement, and diversified product pipelines to mitigate risks. Those who fail to adapt may find themselves trapped in the same cycle of litigation and delayed entry that has defined the past decade.

Source:
[1] Patent Infringement, Regeneron, Pharmaceutical Industry [https://www.jdsupra.com/topics/patent-infringement/regeneron/pharmaceutical-industry/]
[2] Regeneron and Biocon Settle Litigation over EYLEA Biosimilar Yesafili, [https://biologicshq.com/regeneron-and-biocon-settle-litigation-over-eylea-biosimilar-yesafili/]
[3] The Landscape of Regeneron's Eylea® Litigation After the Federal Circuit Affirmed, [https://quicktakes.loeb.com/post/102k069/the-landscape-of-regenerons-eylea-litigation-after-the-federal-circuit-affirmed]
[4] The top 10 drugs losing US exclusivity in 2025 [https://www.fiercepharma.com/special-reports/top-10-drugs-losing-us-exclusivity-2025]