Mexico seizes suspicious Keytruda in raid to dismantle counterfeit medication ring
Federal authorities in Mexico seized vials labeled as Keytruda, the world’s bestselling drug, during an operation to dismantle a counterfeit ring in a suburb outside of the capital city, sources with direct knowledge of the raid told the International Consortium of Investigative Journalists Friday. This is the second operation that has led to arrests where vials labeled as the cancer medication were seized.
In a joint operation in March, Mexico’s security ministry, Secretariat of the Navy (known as SEMAR) and the Attorney General’s office seized 15,000 doses of clonazepam, more than 100 counterfeit vaccines and 1,000 vaccine labels, believed to be used to produce falsified medication, according to an April press release. They also found guns, cocaine and five vials labeled Keytruda, two sources told ICIJ. Merck could not confirm whether the vials were real or counterfeit.
Keytruda, known generically as pembrolizumab, has been a game changer in cancer treatment — with a price to match. ICIJ’s Cancer Calculus investigation, published in April, revealed how the high cost of the drug has fueled demand for counterfeits.
Vials that appear to be labeled as Keytruda found in a raid by Mexican authorities in the town of Huixquilucan. Image: Mexico Security Ministry
The investigation, which brought together reporters in 37 countries, exposed the inner workings of a system that protects pharmaceutical pricing monopolies and prioritizes profit over access. Keytruda is produced by the pharmaceutical company Merck and Co., known as MSD outside of the United States and Canada.
In Mexico, reporters from Quinto Elemento Lab, El País, El Sol de México and Univision found that falsified vials of the cancer drug were supplied to public hospitals through medication distributors that, at times, do not comply with national health standards. One patient died while being infused with fake Keytruda, Merck confirmed as part of ICIJ’s previous reporting. Another patient, whose case was documented by Univision, claimed to suffer painful side effects after being administered falsified Keytruda twice in a public hospital in Mérida, the largest city in the state of Yucatán.
Only Merck can confirm if vials are authentic or counterfeit, since the patented formula is known only to the company. The five vials seized in the March raid remain in the custody of authorities and have not yet been provided to MSD for analysis, Anthony Zook, associate vice president for MSD Global Security, said in a statement to ICIJ.
“Therefore, we are not in a position to confirm their authenticity or whether they are genuine or falsified,” Zook said. “We continue to closely monitor the situation and stand ready to support the authorities should our technical expertise be requested.”
Two people, a man and a woman, were arrested during the March raid in the town of Huixquilucan, 59 miles west of Mexico City, according to the press release.
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/
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