What is the Cancer Calculus investigation?

The Cancer Calculus is a yearlong investigation by the International Consortium of Investigative Journalists that reveals how Merck & Co. keeps the price of its blockbuster cancer drug Keytruda extraordinarily high while stifling competition.

The investigation, led by ICIJ in collaboration with 47 media partners, shows how the pharmaceutical giant has exploited the global patent system and pushed to widen Keytruda’s use, even in cases with limited benefits, driving up costs for patients and hospitals. The Cancer Calculus draws on hundreds of interviews with oncologists, cancer patients and their families, patent experts, regulators, pharmaceutical industry insiders and others to tell the story of a breakthrough medicine whose transformative power has been constrained by its manufacturer’s quest for profits.

ICIJ and its partners filed 1,018 public record requests in 27 countries to unearth public health records, meeting minutes, pricing and reimbursement data, and other documents in order to pull back the curtain on how Merck maintains Keytruda’s dominance, even as countless patients struggle to access the lifesaving treatment.

What is Keytruda?

Keytruda, known generically as pembrolizumab, is a type of immunotherapy that restores the body’s ability to fight cancer cells. Unlike chemotherapy, which targets rapidly dividing cancer cells, Keytruda disrupts a process that allows some cancers to circumvent the immune system.

The U.S. Food and Drug Administration approved it in 2014 to treat advanced melanoma, the most aggressive form of skin cancer. The FDA has since approved it for 19 types of tumors.

What are some of the key findings of the Cancer Calculus investigation?

The Cancer Calculus found that Merck and other cancer research businesses exploited the patent system to build a fortress around Keytruda of at least 1,212 patent applications in 53 countries, regions and territories. This stream of follow-on patents could help Merck stifle competition and maintain high prices — and billions of dollars in revenue — for 14 years after its original patents expire in 2028.

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Merck has promoted a higher dosage of Keytruda than is necessary, according to some leading cancer researchers. The World Health Organization estimates that switching patients with lung cancer to weight-based dosing could save $5 billion globally by 2040.

The drug giant has taken advantage of industry regulatory shortcuts, orchestrated a costly global lobbying campaign, and operated with a gross lack of transparency in pricing. It has distributed tens of millions of dollars in the U.S. in consulting fees, travel costs and other Keytruda-related payments to doctors and health-care professionals.

An ICIJ analysis shows that Merck has generated about $163 billion in Keytruda sales since 2014, reaching more than 3 million people. The company funneled nearly $75 billion in dividends to shareholders and $43 billion into share buybacks while reducing its U.S. taxes by recording profits in lower-tax jurisdictions. In its 2025 annual report, Merck disclosed it paid around $1.6 billion in U.S. income taxes, compared with $4.5 billion in other countries, including $2.1 billion in Switzerland.

Meanwhile, Keytruda’s steep prices are straining government budgets, even in wealthy countries. List prices for a typical treatment range from about $80,000 a year in Germany to $208,000 in the U.S., $93,000 in Lebanon to about $130,000 in Colombia, and $65,000 in South Africa to $116,000 in Croatia. According to ICIJ’s analysis, Keytruda is more expensive for median income earners in the U.S. and poorer Eastern European countries, like Bulgaria and Hungary, than in some wealthy Western European countries.

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How did Merck & Co. respond to ICIJ’s findings?

The CEO and chairman of Merck & Co., Robert M. Davis, declined to comment. But Merck senior vice president Johanna Herrmann defended the company’s pricing practices.

“We have a long history of responsibly pricing our medicines to reflect their value to patients, payers and society,” she said in a letter to ICIJ.

Herrmann acknowledged in a separate letter that Merck faces “increasing political and business pressures” over access and pricing in emerging markets. But she said the company is working to ensure health care is “affordable, efficient, equitable and sustainable on a global scale.”

What data was used in the Cancer Calculus investigation?

ICIJ and its partners obtained data from a wide range of public and exclusive sources. For pricing information, the Austrian National Public Health Institute (GÖG) gathered and calculated the price data in national currency units (unweighted raw data) from national databases as part of its PPI (Pharma Price Information) service. ICIJ also gathered pricing information from Merck’s website, government sources, and Knowledge Ecology International’s drugdatabase.info.

To analyze patents, ICIJ first identified U.S. Keytruda patents and cross-checked them against the Initiative for Medicines, Access & Knowledge (I-MAK)’s research, then built patent families using Espacenet and Google Patents.

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Merck’s Keytruda-related payments to U.S. doctors and health care professionals are tracked in the U.S. government’s Open Payments database. The company discloses payments to U.S.-based patient groups through grants. ICIJ cross-checked that data with KFF’s list of advocacy organizations. In Belgium, De Tijd gathered data from betransparent.be that was used to identify payments made by MSD Belgium to patient and health care organizations. ICIJ cross-checked that information with LobbyFacts.

Swiss advocacy organization Public Eye analyzed Keytruda’s research and development costs for ICIJ and its partners, relying on clinicaltrials.gov data. And the Healthcare Cost Institute and Serif Health shared data about treatment costs in the U.S.

ICIJ reviewed 163 judicial requests from patients requesting access to Keytruda from government health systems in Guatemala, Mexico and Chile. For Brazil, judicial requests were gathered from a public dashboard. ICIJ also analyzed 27 decisions related to Keytruda access from the California Department of Managed Healthcare’s public search engine.

https://www.icij.org/investigations/cancer-calculus/merck-keytruda-cancer-drug-price/

OVERVIEW How Merck turned its wonder drug into a blockbuster — and priced out cancer patients worldwide Apr 13, 2026

https://www.icij.org/investigations/cancer-calculus/cancer-drug-counterfeits-keytruda-immunotherapy/

COUNTERFEITS Counterfeiters cash in on the world’s bestselling cancer drug Apr 13, 2026

https://www.icij.org/investigations/cancer-calculus/cancer-patients-legal-battle-keytruda-lifesaving-drug/

INSURERS ‘They deny the medication that is keeping you alive’: Patients wage grueling legal battles for lifesaving cancer drug Apr 13, 2026

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yearlong investigation by the International Consortium of Investigative Journalists has uncovered how Merck & Co. has kept the price of its blockbuster cancer drug Keytruda extraordinarily high while deterring competition.

The Cancer Calculus, an investigation by ICIJ and 47 media partners in 37 countries, also sheds new light on the strategies that have allowed Merck to widen Keytruda’s use — even in cases where its benefits are more limited and lower dosages may be just as effective.

A game changer in cancer treatment, Keytruda, known generically as pembrolizumab, weaponizes a patient’s immune system against cancer cells. The U.S. Food and Drug Administration approved it in 2014 to treat advanced melanoma, the most aggressive form of skin cancer. The FDA has since approved it for 19 types of tumors.

ICIJ’s investigation found that Merck’s list prices, or the initial pre-discount prices, vary wildly across countries, ranging from about $850 for a single 100 milligram vial in Indonesia to $6,015 for the same vial in the U.S.

Usually administered via intravenous infusion in 200 mg doses every three weeks or 400 mg doses every six weeks, treatment can last up to two years — amounting to a staggering $416,000 according to the drug’s list price in the U.S. — and sometimes longer, though insurance companies often stop covering the drug after the initial two years.

With the cost of prescription drugs continually soaring, President Donald Trump convened top executives from major drug companies at the White House this past December and promised to lower U.S. drug prices. Among the executives was Robert M. Davis, head of Merck. All the companies pledged price cuts, but Merck made no such commitment with Keytruda, which generated $31.7 billion in 2025 — nearly half the company’s revenue. And 60% of the drug’s sales were in the U.S.

U.S. President Donald Trump shakes hands with Merck CEO Robert Davis during the White House event announcing lower drug prices in December. Image: Alex Wong/Getty Images

Based on hundreds of interviews with oncologists, cancer patients and their families, patent experts, regulators, pharmaceutical industry insiders and others, as well as exclusive pricing data and patent analyses, together with thousands of pages of company presentations, patent board documents, lawsuits and corporate and regulatory records, and more than 1,000 public records requests in 27 countries, the Cancer Calculus investigation pulls the curtain back on precisely how Merck maintains its dominance.

A patent fortress: An ICIJ analysis of Keytruda patents based on patent databases and data shared by I-MAK, a nonprofit that examines inequities in the patent system, shows that there are at least 1,212 patent applications that form part of the Keytruda patent families in 53 countries, regions and territories. The drug’s primary patents are set to expire in 2028, but ICIJ found that Merck has continued to file and obtain secondary patents beyond Keytruda’s main pharmaceutical component, potentially extending the drug’s commercial exclusivity until at least 2042 in the U.S. These additional patents, which can overwhelm and deter competitors, could deny hundreds of thousands of patients cheaper alternatives over the next 15 years.

Merck told ICIJ that it’s a common myth that pharmaceutical companies “game the patent system” by filing multiple overlapping patents to delay the entry of generic or biosimilar alternatives to the market. Instead, the company said, it had been repeatedly shown that patent counts do not predict when generics are introduced.

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Calculated dosing: Researchers report that Keytruda is often prescribed at higher doses or for longer periods than needed. The World Health Organization estimates that switching just patients with lung cancer to weight-based dosing could save $5 billion globally by 2040. Hospitals in Singapore, Malaysia and Taiwan have arrived at the same conclusion, and several nations, including the Netherlands, Canada and Israel, have started to switch to weight-based dosing — in which a patient’s body weight determines how much medication to use — with promising results.

Merck told ICIJ that while strategies to save health care costs were vital, it was more vital to provide appropriate care to patients, especially for potentially life-changing drugs such as pembrolizumab. “The two FDA-approved dosing regimens for KEYTRUDA for the treatment of cancer are based upon wide-ranging preclinical data and extensive clinical evidence,” the company said in its statement to ICIJ, adding that guidance on dosing varied depending on the type of cancer and whether Keytruda was used alone or in combination with other treatments.

Prescribing influence: Merck has invested financially — and heavily — in relationships with doctors and patient groups and in the distribution of research grants. Studies show such payments increase prescriptions, sometimes without improving survival rates. In the U.S. alone, records show, Merck made nearly $52 million in Keytruda-related consulting and other payments to health care professionals from 2018 to 2024, with five doctors receiving more than $1 million each.

Blockbuster profits: Merck’s targeted medical influence practices, combined with aggressive marketing, have helped Keytruda reach about $163 billion in sales since 2014, making it one of the bestselling drugs of all time. Meanwhile, the company has funneled nearly $75 billion in dividends to shareholders and $43 billion into share buybacks.

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Sky-high pricing: Prices for Keytruda vary widely but remain high everywhere. ICIJ found Keytruda treatment costs for patients are particularly uneven in the U.S. Data compiled by Serif Health, a San Francisco firm that analyzes health care reimbursement information and shared with ICIJ, show that patient and insurer costs vary dramatically. Across the U.S., estimated costs range from $5,858 to $43,800 for a typical 200 mg Keytruda treatment, depending on where the drug is given, which commercial insurance company and provider are involved, and how it’s billed.

Merck told ICIJ it had a long history of “responsibly pricing our medicines to reflect their value to patients, payers and society.” It also said that to ensure its products reached as many patients as possible, it priced them “differentially across markets, and sometimes within markets, according to numerous factors.”

Those factors, the company said, included the value a therapy brings to patients and the health care system, countries’ pricing and reimbursement systems, and the ability of governments to finance health care.

R&D rodeo: Merck claims to spend tens of billions of dollars in development of Keytruda, but a new analysis by Public Eye, a Swiss-based nonprofit advocating for corporate accountability, estimates Keytruda’s research and development costs at $1.9 billion — 1% of the drug’s global revenue since its launch in 2014. Adding the cost of failed clinical trials, the R&D estimate is $4.8 billion, or 3% of the drug’s revenue. Patrick Durisch, Public Eye’s pharma specialist, said he based his numbers on a review of Keytruda clinical trials and their average costs — the largest share of R&D expenses. Critics argue that Merck’s prices are driven more by profit-seeking than innovation costs.

The investigation also shows how the market maneuvers can lead to desperate measures: Patients often turn to crowdfunding or even black markets in search of cheaper prices. Since Keytruda came to market in 2014, ICIJ found 632 cases in which patients in 51 countries used GoFundMe and other crowdfunding sites to raise money for Keytruda treatments. Some patients turn to the court systems for access to Keytruda, only to die waiting for a verdict.

Doctors in poorer countries can be forced to ration treatment, deciding who lives and who goes without. The high price of Keytruda has also helped fuel a trade in counterfeit versions of the drug. In Mexico, for example, ICIJ and partners identified four cases in which fake Keytruda was supplied to hospitals.

The Cancer Calculus highlights how a system that protects pharmaceutical pricing monopolies prioritizes profit over access. The project also shows that Merck used regulatory shortcuts such as accelerated approvals and orphan drug designations (for any rare disease that the FDA says affects fewer than 200,000 people in the U.S.) to maintain its dominance and protect its profit margin even as patients wage desperate struggles to stay alive.

Keytruda has undeniably transformed cancer care by extending survival for patients with melanoma and lung cancers, as well as other hard-to-treat tumors. It even helped former president Jimmy Carter live years longer after he developed advanced skin cancer. But the Cancer Calculus reveals that Merck’s secret pricing negotiations with governments around the globe have reinforced a world of inequity where burdened health care systems foot the bill — sometimes at the expense of other drugs they can no longer afford to pay for — and doctors are forced to choose which patients they can treat.

Ultimately, the Cancer Calculus is a case study of a broken global system for drug pricing and distribution. These stories highlight the urgent need to rethink how the world balances innovation, cost and access. For hundreds of thousands of patients, that balance will determine their survival.

https://www.icij.org/investigations/cancer-calculus/cancer-drug-counterfeits-keytruda-immunotherapy/

COUNTERFEITS Counterfeiters cash in on the world’s bestselling cancer drug Apr 13, 2026

https://www.icij.org/investigations/cancer-calculus/merck-keytruda-cancer-drug-price/

OVERVIEW How Merck turned its wonder drug into a blockbuster — and priced out cancer patients worldwide Apr 13, 2026

https://www.icij.org/investigations/cancer-calculus/cancer-patients-legal-battle-keytruda-lifesaving-drug/

INSURERS ‘They deny the medication that is keeping you alive’: Patients wage grueling legal battles for lifesaving cancer drug Apr 13, 2026

Recommended reading COUNTERFEITS Counterfeiters cash in on the world’s bestselling cancer drug Apr 13, 2026 OVERVIEW How Merck turned its wonder drug into a blockbuster — and priced out cancer patients worldwide Apr 13, 2026 INSURERS ‘They deny the medication that is keeping you alive’: Patients wage grueling legal battles for lifesaving cancer drug Apr 13, 2026