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.

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.

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.

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.

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Who are ICIJ’s partners on the Cancer Calculus investigation?

The ICIJ-led investigation included 124 journalists from 48 newsrooms: Paper Trail Media, DER SPIEGEL and ZDF in Germany; Reporters United in Greece; L’Espresso in Italy; direkt36 in Hungary; El Espectador in Colombia; Plaza Pública in Guatemala; El Sol de México and Quinto Elemento Lab in Mexico; El País in Mexico and Spain; La Nación in Costa Rica; DARAJ in Lebanon; Yle in Finland; USA Today in the U.S.; The Bureau of Investigative Journalism in the U.K.; KCIJ-Newstapa in South Korea; and 31 others.

How can I join an ICIJ investigation?

ICIJ welcomes new offers to collaborate with journalists and prioritizes those with a proven record of high-quality investigations. Journalists seeking to partner with ICIJ should email contact@icij.org. ICIJ only partners with journalists.

How do I get in touch with ICIJ if I want to share a tip or documents?

ICIJ ​encourages​ ​whistleblowers​ ​to ​submit​ ​all​ ​forms​ ​of​ ​content​ ​that​ ​might​ ​be​ ​of​ ​public​ ​concern​ — ​documents,​ ​photos, video​ ​clips​ ​and​ ​story​ ​tips — and to do so securely. We​ ​accept​ ​all​ ​information​ ​that​ ​relates​ ​to​ ​potential​ ​wrongdoing​ ​by​ ​corporate,​ ​government​ ​or public​ ​service​ ​entities​ ​in​ ​any​ ​country,​ ​anywhere​ ​in​ ​the​ ​world.​ ​We​ ​do​ ​our​ ​utmost​ ​to​ ​guarantee the​ ​confidentiality​ ​of​ ​our​ ​sources.

Find out how to contact us securely here.

Who funds ICIJ?

ICIJ relies entirely on donations to fund our work. Please consider donating to ICIJ.

Some of the philanthropic foundations that fund ICIJ have programs or campaigns advocating for reform of the pharmaceutical industry to increase transparency, affordability and access to health care. Funders have no involvement in ICIJ’s editorial decisions.

You can find a list of our recent supporters here.

How do I speak to an ICIJ journalist about the Cancer Calculus investigation?

Please direct requests to media@icij.org or call +1 202-808-3310.