A yearlong international investigation into one of the world’s most important cancer drugs shows how a medical breakthrough has also become a fault line in global health, exposing how pricing systems, patent protections and regulatory frameworks determine who can access life-saving treatment and who cannot.
The Cancer Calculus, coordinated by the International Consortium of Investigative Journalists (ICIJ) with Deutsche Welle and 46 media partners, brought together 124 journalists in 37 countries. Drawing on hundreds of interviews with oncologists, patients and their families, lawyers, regulators, pharmacists, pharmaceutical industry insiders and others as well as exclusive pricing data and patent analyses, the project examines how Merck’s cancer drug Keytruda became both a therapeutic milestone and a symbol of unequal access. ICIJ’s media partners also obtained public health records, meeting minutes, and pricing and reimbursement data through at least 1,018 public records requests across 27 countries.
Partners including The Indian Express, De Tijd, El País, La Nación and DW Turkish documented how the drug’s impact varies dramatically across regions — from hospitals forced to ration treatment to patients turning to courts or crowdfunding to survive.
A drug that changed cancer care
Keytruda (pembrolizumab), first approved in 2014, belongs to a class of immunotherapy drugs that enable the immune system to attack cancer cells. Now approved for at least 19 types of tumors, it has extended survival for millions and, in some cases, turned previously fatal diagnoses into manageable conditions.
But it has also become one of the most best sellings drugs in pharmaceutical history. Keytruda generated $31.7 billion (€27.1 billion) in sales in 2025 — nearly half of Merck’s total revenue — and around $163 billion globally since its launch. About 60% of those sales come from the United States. Meanwhile, the company has funneled nearly $75 billion in dividends to shareholders and $43 billion into share buybacks.
Keytruda’s global expansion has accelerated sharply in recent years. From 2020 to 2024, sales rose by 232% in France to $2.8 billion, 265% in Brazil to $753.7 million, 491% in Mexico to $137.3 million, and 584% in Turkey to nearly $100 million, according to exclusive data shared with ICIJ by the IQVIA Institute for Human Data Science.
As drug prices continue to rise, US President Donald Trump met with pharmaceutical executives in December and pledged to lower costs. While companies signaled price cuts, Merck did not publicly commit to reductions for Keytruda.
At the same time, the cost of treatment has placed growing pressure on health systems worldwide. Annual treatment costs — about $80,000 in Germany to $208,000 in the United States, $93,000 in Lebanon to around $130,000 in Colombia, and from roughly $65,000 in South Africa to $116,000 in Croatia — are straining government budgets, even in wealthy countries.
In the United Kingdom, research has shown that the National Health Service has overpaid for Keytruda in some cases, with one study finding that the drug cost up to five times more than its assessed value for certain lung cancer patients.
Prices, patents and power
The investigation found that Merck has relied on a combination of legal and commercial strategies to maintain its dominance.
One of the most significant is its extensive use of the patent system. Reporters identified at least 1,212 patent applications related to Keytruda across 53 jurisdictions. While the drug’s main patents are set to expire in 2028, follow-on patents could extend market exclusivity until at least 2042, delaying cheaper alternatives for more than a decade.
Critics describe this as a “patent fortress” designed to deter competition. Merck rejects that characterization, saying its filings reflect ongoing innovation, including new uses, formulations and combinations.
The investigation also points to regulatory pathways and lobbying efforts that helped expand the drug’s use, alongside financial relationships with doctors and patient groups. In the United States alone,records show that Merck made Keytruda-related payments to healthcare professionals totaling nearly $52 million between 2018 and 2024.
Merck says such collaborations help inform the medical community and improve patient care, and that any support for patient organizations is independent of prescribing decisions.
The scale of Keytruda’s development costs is also contested. In 2024 congressional testimony, Merck CEO Robert M. Davis said the company had invested $46 billion between 2011 and 2023 to research, develop and manufacture the drug, citing more than 2,200 clinical trials and plans to invest another $18 billion in future studies.
But an analysis by Swiss nonprofit Public Eye estimates the drug’s R&D costs at around $1.9 billion, or about 1% of its global revenue since launch. Even when costs of failed trials are included that estimate only rises to $4.8 billion, or roughly 3% of total revenue.
Extreme prices, opaque systems
Keytruda’s list prices vary widely, from about $850 per vial (100 mg) in Indonesia to more than $6,000 in the United States, reflecting opaque pricing systems shaped by confidential discounts and negotiations.
Even where prices appear lower, affordability is often worse. In the United States, a patient earning the median income can afford fewer than five doses per year.
In South Africa, by contrast, a person earning the median income cannot afford even a single dose (200 mg) in a year, underscoring how differences in income — not just price — determine access.
According to ICIJ’s analysis, people with median incomes in the United States can afford less Keytruda than those in some Western European countries such as France and Belgium, while the drug is even less affordable in lower-income Eastern European countries like Bulgaria and Hungary.
In India, where access largely depends on out-of-pocket payments or limited assistance programs, treatment costs can exceed a patient’s annual income, effectively restricting access to a small share of the population.
In Brazil, the high cost of cancer drugs has driven a surge in litigation, with thousands of lawsuits filed in recent years as patients seek court-ordered access to treatment. Similar patterns have been observed across Latin America, where legal systems have become a critical pathway to access.
The investigation also documented cases in which limited supply forced doctors to make life-and-death decisions. In Guatemala, one oncologist described being forced to choose which patients would receive treatment, saying it felt like “playing God.”
Since Keytruda came to market in 2014, ICIJ found at least 632 cases in which patients in 51 countries used GoFundMe and other crowdfunding sites to raise money for Keytruda treatments. In some cases, patients have turned to black markets, exposing themselves to counterfeit medicines. Others have taken governments to court — and in some cases died before their claims were resolved.
Across countries, a common feature emerges: secrecy. Authorities in several countries refused to disclose public spending or patient numbers for Keytruda, often citing “trade secrets,” making it difficult to compare prices or assess fairness across health systems.
Turkey: Price policy, reimbursement gaps and litigation
Against this global backdrop, Turkey illustrates how pricing policy, reimbursement rules and judicial processes intersect in access to high-cost cancer drugs.
In Turkey, drug prices are calculated based on a government-set fixed euro exchange rate, which is typically below the market rate. As of April 1, 2026, the reference rate was increased to 29.11 Turkish lira, and the retail price rose to 88,783.52 lira per vial (approximately €3,049).
The drug is administered in two doses every three weeks, bringing the cost of a single treatment cycle to approximately 177,567 lira (€6,099). This corresponds to about 6.5 times the monthly net minimum wage in Turkey, which stands at 28,075.50 lira.
For years, Keytruda remained outside the Social Security Institution (SSI) reimbursement system, pushing patients to seek access through the courts. The drug entered reimbursement in July 2025 for six indications, but eligibility restrictions and off-label uses continue to generate disputes.
A DW Turkish analysis of 50 lawsuits filed in Turkey shows how legal processes themselves have become a defining factor in access. In 10 out of 34 open labor court cases, the patient died while proceedings were still ongoing.
This points to a structural problem: even where a legal right to treatment exists, delays in the judicial process can render that right ineffective, particularly in life-threatening conditions such as cancer.
Dosing debates and rising costs
The investigation also raises questions about how the drug is prescribed. Some researchers argue that Keytruda is often administered at higher doses than necessary.
The World Health Organization estimates that switching to weight-based dosing for lung cancer patients alone could save around $5 billion globally over 15 years, based on modeling scenarios.
Hospitals in several countries have begun testing lower-dose approaches, with early findings suggesting similar effectiveness. 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 maintains that its dosing recommendations are based on extensive clinical evidence and regulatory approvals.
Merck: Prices reflect value
In responses to ICIJ, Merck defended its pricing strategy, saying Keytruda’s price “reflects its value to patients and health care systems.”
Merck also said that access to medicines is “multifactorial,” depending on healthcare systems, reimbursement policies and infrastructure, not just price.
The company said it uses differential pricing across markets and operates patient assistance programs. It added that it actively engages in access programs in low- and middle-income countries to expand availability. In the United States, it reported providing $1.7 billion in free medicines across its portfolio in 2024, along with about $125 million in co-pay assistance.
Merck also pointed to broader systemic factors, including insurers and intermediaries, as major drivers of high costs, particularly in the US.
Merck has not publicly detailed how it calculates R&D costs for individual medicines but has consistently argued that pricing reflects long-term investments and risks across its portfolio.
At the same time, the company acknowledged “increasing political and business pressures” over pricing and access, especially in emerging markets, but said it is working to make healthcare more “affordable, efficient, equitable and sustainable.”
A global system under pressure
The investigation concludes that Merck’s practices are not unique, but reflect broader dynamics in the pharmaceutical industry where patent protections, pricing strategies and regulatory frameworks often favor manufacturers.
For patients, however, the consequences are immediate.
Access to a life-extending treatment often depends not only on medical need, but on geography, income and the ability to navigate complex legal and financial systems.
For Nasır Nesanır, chair of the public health branch of the Turkish Medical Association, these disparities point to deeper structural questions. Speaking to DW Turkish, he said the issue goes beyond healthcare itself.
“Should medical innovation be regarded as a common gain of humanity?” Nesanır asked. “Or should it remain a commercial asset under patent protection that deepens global inequality?”
The result is a deep global divide, where a breakthrough drug can mean survival for some, and remain out of reach for many others.
