Senate Scrutiny Intensifies: The Battle Over Keytruda, Patent "Gimmicks," and the Future of Cancer Care

In a significant escalation of congressional oversight regarding the pharmaceutical industry’s pricing strategies, U.S. Senator Maggie Hassan (D-N.H.) has launched a pointed inquiry into Merck & Co., demanding accountability for what she characterizes as anti-competitive patent practices surrounding the blockbuster cancer immunotherapy, Keytruda. As the ranking member of the Senate Finance Subcommittee on Health Care, Hassan’s intervention signals a growing bipartisan appetite for curbing the tactics that keep life-saving medications prohibitively expensive for millions of patients.

At the heart of the dispute is the practice of “evergreening”—a strategy wherein drug manufacturers secure a thicket of secondary patents for minor modifications to existing drugs, effectively extending their market monopoly well beyond the expiration of their primary patents. For patients and healthcare systems worldwide, this translates into years of inflated costs and restricted access to biosimilar competition.

The Core Allegations: Patent Thickets and “Product Hopping”

Senator Hassan’s letter to Merck CEO Robert Davis, sent earlier this week, is a direct challenge to the company’s intellectual property strategy. The senator has requested a granular explanation of the patent maneuvers linked to both the established intravenous version of Keytruda—a staple of oncology treatment for over a decade—and the newer injectable formulation, which hit the market last year.

“I continue to have serious concerns about how Merck’s anti-competitive practices have boosted profits at the expense of patients,” Hassan wrote. She contends that these “patent gimmicks” are designed to create a regulatory fortress, delaying the entry of lower-cost biosimilars into the marketplace while allowing Merck to implement annual price hikes in the United States.

The inquiry is informed by the “Cancer Calculus” investigation conducted by the International Consortium of Investigative Journalists (ICIJ). The investigation exposed how pharmaceutical giants use a combination of strategic pricing, dosing shifts, and aggressive patent filings to maintain dominance. According to the data, Merck and its research partners have filed 1,212 patent applications across 53 jurisdictions. While the primary patents for Keytruda are slated to expire in 2028, these secondary filings could potentially grant the company market exclusivity until at least 2042.

A Chronology of Market Dominance and Oversight

To understand the current tension, one must look at the timeline of Keytruda’s rise and the subsequent legislative pushback:

• 2014: Keytruda receives initial FDA approval, beginning its trajectory as a global oncology blockbuster.
• 2014–2023: Merck files over a thousand patent applications globally, covering various aspects of the drug, including methods of administration and dosing regimens.
• 2023: Merck launches an injectable version of Keytruda, a strategic move that critics argue is designed to shift patients away from the intravenous version just as competition looms.
• Early 2024: During a Senate hearing, Sen. Hassan challenges Merck CEO Robert Davis on the company’s commitment to allowing biosimilar entry. Davis asserts that the company supports a robust generic market and will not block biosimilars once primary patents expire.
• June 2024: The Senate Committee on Health, Education, Labor, and Pensions advances the Medication Affordability and Patent Integrity Act, co-sponsored by Hassan and Sen. Josh Hawley (R-MO).
• July 2024: Senator Hassan issues a formal demand for information to Merck, requiring a response by July 20 regarding the potential for “product hopping”—the practice of switching patients to a new version of a drug to reset the clock on patent protection.

Supporting Data: The High Cost of Exclusivity

The financial data surrounding Keytruda reveals a global disparity in access. Because the drug is protected by a vast web of patents, Merck has been able to set list prices that strain the budgets of even the most affluent nations.

Current pricing benchmarks illustrate the severity of the issue:

• United States: Up to $208,000 per year.
• Colombia: Approximately $130,000 per year.
• Lebanon: Approximately $93,000 per year.
• Germany: Over $80,000 per year.

These exorbitant costs have created a secondary, dangerous ripple effect. The high price point has fueled an illicit global trade in counterfeit cancer medication, with suspicious supplies of Keytruda being seized in jurisdictions like Mexico. Beyond the threat of counterfeit drugs, the financial burden has forced countless patients into protracted legal battles with insurance providers, fighting for the coverage necessary to access treatment.

Official Responses and Corporate Defenses

In response to the growing scrutiny, Merck has consistently maintained that its patent practices are standard industry procedure, intended to protect innovation. When reached for comment regarding the ICIJ investigation earlier this year, a spokesperson for the company described the notion that companies use “patent thickets” to block competition as a “common myth.”

The company argues that the number of patents filed does not dictate the timing of biosimilar or generic entry into the market. Merck contends that its R&D investment, which has been substantial, necessitates long-term protection to ensure the continued development of new cancer therapies. However, this defense has failed to satisfy regulators, who argue that the sheer volume of secondary patents creates a legal barrier that few biosimilar manufacturers have the resources or risk tolerance to challenge.

During the 2024 Senate hearing, CEO Robert Davis emphasized that the system requires both patent protection and a healthy biosimilar environment. Yet, Senator Hassan’s recent letter points out the logical disconnect in this position: “Despite these statements, existing patents for intravenous Keytruda and a new form of the medication may help block or minimize competition from biosimilars for years.”

Implications for the Pharmaceutical Industry

The inquiry into Keytruda is not an isolated event; it is a flagship case in a broader, systemic challenge to the U.S. healthcare model. The Medication Affordability and Patent Integrity Act represents the legislative manifestation of this frustration. If passed, the bill would reform the patent review process, making it more difficult for companies to use secondary patents to create “evergreening” scenarios.

The Impact on Innovation vs. Affordability

The pharmaceutical industry often argues that any restriction on patent rights will stifle innovation. However, lawmakers like Hassan are increasingly distinguishing between “meaningful innovation”—such as the discovery of a new molecule—and “strategic innovation,” which involves minor tweaks to administration or formulation specifically intended to prolong monopoly status.

The Regulatory Landscape

If the Senate successfully forces transparency regarding Merck’s secondary patents, it could set a powerful precedent. Other pharmaceutical companies holding major cancer therapies with approaching patent cliffs may face similar inquiries. This could lead to:

1. Increased Scrutiny from the USPTO: The United States Patent and Trademark Office may face pressure to increase the threshold for secondary patent approvals.
2. Market Realignment: Companies may shift their strategies to rely less on “patent walls” and more on legitimate therapeutic advancements to maintain market share.
3. Biosimilar Acceleration: By challenging the validity of these patent thickets, the government could significantly reduce the time it takes for lower-cost, high-quality biosimilars to enter the U.S. market, potentially saving billions in healthcare spending.

Conclusion: The July 20 Deadline and Beyond

The deadline of July 20 for Merck to respond to Senator Hassan’s 10 questions serves as a critical checkpoint. The senator’s questions are direct: Why does Merck rely on such a high number of secondary patents? How does the transition to an injectable version serve the patient versus the company’s bottom line? And what specific, actionable steps is the company taking to ensure that, come 2028, the path is truly clear for biosimilar competition?

For the patients relying on Keytruda, the stakes are not merely financial—they are a matter of survival. As Congress continues to pull back the curtain on the business of oncology, the pharmaceutical industry finds itself at a crossroads. The era of “patent-driven” market dominance is under siege, and the outcome of the battle over Keytruda will likely define the legislative framework for drug pricing and intellectual property for years to come.

Whether Merck chooses to offer transparency or further defend its status quo, the message from the Senate is clear: the era of unchecked “patent gimmicks” is being challenged, and the cost of the status quo is a price the American public is increasingly unwilling to pay.