The world's top-selling drug
Keytruda (pembrolizumab), first approved in 2014, is now approved for at least 19 types of tumors [1][2]. In 2025, it generated $31.7 billion in sales, and has brought in around $163 billion globally since its launch [3][4]. About 60% of those sales come from the United States [5]. Meanwhile, Merck funneled nearly $75 billion in dividends to shareholders and $43 billion into share buybacks [6].
Sales have surged in multiple countries. From 2020 to 2024, Keytruda sales rose by 232% in France to $2.8 billion, by 265% in Brazil to $753.7 million, by 491% in Mexico to $137.3 million, and by 584% in Turkey to nearly $100 million [7][8][9][10].
A global price chasm
The price of Keytruda varies enormously. Annual treatment costs range from about $65,000 in South Africa to $208,000 in the United States [15][12]. In Germany, it is about $80,000; in Lebanon, $93,000; in Colombia, $130,000; in Croatia, $116,000 [11][13][14][16]. Per vial (100 mg), the list price is about $850 in Indonesia and more than $6,000 in the United States [24][25].
In the United Kingdom, the NHS overpaid for Keytruda in some cases, with one study finding the drug cost up to five times more than its assessed value for certain lung cancer patients [17].
Patent thickets extend exclusivity
Reporters identified at least 1,212 patent applications related to Keytruda across 53 jurisdictions [18]. Keytruda's main patents are set to expire in 2028, but follow-on patents could extend market exclusivity until at least 2042 [19][20].
Merck made Keytruda-related payments to healthcare professionals in the US totaling nearly $52 million between 2018 and 2024 [21]. Merck CEO Robert M. Davis said the company invested $46 billion between 2011 and 2023 to research, develop and manufacture Keytruda [22]. An analysis by Swiss nonprofit Public Eye estimates Keytruda's R&D costs at around $1.9 billion [23].
Unaffordable for many
In the United States, a patient earning the median income can afford fewer than five doses of Keytruda per year [26]. In South Africa, a person earning the median income cannot afford even a single dose (200 mg) in a year [27]. Since Keytruda came to market in 2014, ICIJ found at least 632 cases in which patients in 51 countries used crowdfunding to raise money for Keytruda treatments [28].
In Turkey, the situation is stark. As of April 1, 2026, the reference exchange rate for drug pricing was increased to 29.11 Turkish lira per euro [29]. The retail price per vial is 88,783.52 lira (approximately €3,049) [30]. A single treatment cycle costs approximately 177,567 lira (€6,099) [31]. The monthly net minimum wage is 28,075.50 lira, meaning a treatment cycle costs 6.5 times the minimum wage [32]. Keytruda entered the Turkish SSI reimbursement system in July 2025 for six indications [33]. A DW Turkish analysis of 50 lawsuits found that in 10 out of 34 open labor court cases, the patient died while proceedings were ongoing [34].
What to watch next
The WHO estimates that switching to weight-based dosing for lung cancer patients could save around $5 billion globally over 15 years [35]. Merck reported providing $1.7 billion in free medicines across its portfolio in 2024 in the United States, and about $125 million in co-pay assistance [36][37]. But as patent cliffs approach and new biosimilars emerge, the pressure on Merck to lower prices—or face compulsory licensing—will only grow.
