An international, yearlong investigation led by the International Consortium of Investigative Journalists, Deutsche Welle and 46 media partners examined how Merck’s cancer immunotherapy Keytruda (pembrolizumab) became both a major medical advance and a focal point of unequal access to care. Reporters reviewed hundreds of interviews, exclusive pricing and patent records, and more than 1,000 public records requests across 27 countries to show how pricing systems, patents and regulatory rules shape who can get this life‑saving treatment.
A medical milestone and a commercial powerhouse
First approved in 2014, Keytruda is part of a class of drugs that release brakes on the immune system so it can attack tumors. It is now approved for at least 19 tumor types, has extended survival for millions of patients and in some cases converted fatal diagnoses into chronic conditions.
At the same time Keytruda has become one of the best‑selling medicines in history. In 2025 it generated $31.7 billion in sales and roughly $163 billion since launch, with about 60% of sales in the United States. Merck returned nearly $75 billion in dividends and spent $43 billion on share buybacks. Between 2020 and 2024 sales jumped sharply in several markets: France (+232% to $2.8 billion), Brazil (+265% to $753.7 million), Mexico (+491% to $137.3 million) and Turkey (+584% to nearly $100 million), based on IQVIA data shared with the investigation.
Those revenues contrast with the strain Keytruda places on health systems. Annual treatment costs cited in the probe range from about $80,000 in Germany to $208,000 in the United States, with comparable high prices in Lebanon, Colombia, South Africa and Croatia. Investigations in the UK suggested the NHS may have overpaid in some cases, with prices up to five times assessed value for certain lung cancer patients.
Patents, pricing and market power
Reporters identified at least 1,212 patent applications related to Keytruda across 53 jurisdictions. Primary patents expire in 2028, but follow‑on filings covering new uses, formulations and combinations could extend exclusivity into the 2030s or 2040s, delaying cheaper competitors. Critics call this a patent fortress meant to deter competition; Merck says the filings reflect ongoing innovation.
List prices and confidential discounts produce wide variation between countries. A 100 mg vial costs about $850 in Indonesia and more than $6,000 per vial in the United States, but net prices are often hidden behind secret deals. Affordability is also relative: a median‑income person in the US can afford fewer than five doses a year, while someone on median income in South Africa cannot afford a single 200 mg dose annually.
The company routinely engages in national price negotiations and works with intermediaries. Between 2018 and 2024 Merck made nearly $52 million in Keytruda‑related payments to US healthcare professionals, according to records cited by the probe. Merck says such collaborations inform the medical community and that support for patient groups is independent of prescribing decisions.
Disputed development costs
Merck’s CEO testified that the company invested $46 billion from 2011 to 2023 on researching, developing and manufacturing Keytruda and planned further investment. Independent analysts dispute that scale. The Swiss nonprofit Public Eye estimates core R&D costs around $1.9 billion, rising to $4.8 billion when costs of failed trials are included—figures that represent a small fraction of the drug’s global revenue. Merck does not publish R&D spending broken down by individual medicines.
Secrecy, real‑world consequences and legal routes
A recurring theme in the investigation is opacity. Authorities in multiple countries refused to disclose payments, discounts or patient numbers, citing trade secrets. That secrecy hampers cross‑country comparisons and assessments of fairness.
When public coverage is unavailable or inadequate, patients turn to courts, crowdfunding or private markets. The ICIJ found at least 632 crowdfunding campaigns for Keytruda in 51 countries. In parts of Latin America skyrocketing drug costs have driven thousands of lawsuits seeking court‑ordered access. In countries with limited supply clinicians have sometimes been forced to ration treatment; one oncologist in Guatemala likened choosing who received Keytruda to playing God. The probe documented cases of patients who died while legal claims were pending.
Dosing debates and potential savings
Standard dosing strategies have come under scrutiny. Some researchers and hospitals argue that higher fixed doses are used more often than necessary. The World Health Organization estimated that switching to weight‑based dosing for lung cancer patients alone could save about $5 billion globally over 15 years in modeled scenarios. Hospitals in Singapore, Malaysia and Taiwan testing lower‑dose approaches report similar effectiveness, and countries including the Netherlands, Canada and Israel have begun adopting weight‑based dosing. Merck maintains its dosing recommendations are supported by extensive clinical evidence and regulatory approvals.
Turkey as a detailed example
Turkey illustrates how exchange‑rate rules, reimbursement systems and courts interact. Drug prices there are calculated using a government‑fixed euro reference rate that has often been set below market levels. As of April 1, 2026 the reference rate was raised to 29.11 Turkish lira, producing a retail price of 88,783.52 lira (about €3,049) per vial. Keytruda is typically given in two doses every three weeks, so a treatment cycle costs roughly 177,567 lira (about €6,099), or about 6.5 times Turkey’s monthly net minimum wage of 28,075.50 lira.
Keytruda was not reimbursed by the Social Security Institution for years, prompting patients to seek access through the courts. It entered reimbursement in July 2025 for six indications, but restrictions and disputes over off‑label use remain. A Deutsche Welle analysis of 50 lawsuits found that in 10 of 34 open labor court cases the patient died while proceedings were ongoing, illustrating how judicial delays can negate legal remedies for life‑saving care.
Merck’s response and access efforts
Merck defends Keytruda’s price as reflecting its value to patients and health systems and points to differential pricing, patient assistance programs and targeted access initiatives in low‑ and middle‑income countries. The company reported providing $1.7 billion in free medicines across its portfolio in 2024 and about $125 million in co‑pay assistance. Merck also notes that access depends on multiple actors, including governments, insurers and intermediaries, not only the manufacturer.
Wider implications
The investigation concludes the trends seen around Keytruda are not unique: patent protections, pricing strategies and regulatory frameworks often favor manufacturers and can produce uneven access to new therapies. For patients, outcomes increasingly depend on geography, income and the ability to navigate complex legal and financial systems.
The Keytruda story crystallizes a broader question about medical innovation: should major breakthroughs be treated primarily as shared gains for public health or as commercial assets protected by intellectual property that can exacerbate global inequality? The drug has saved lives for some while remaining out of reach for many others, exposing widening divides in access to advanced care.