5 min readNew DelhiUpdated: Apr 16, 2026 11:44 AM IST
With at least seven Indian manufacturers in the race to develop generic versions of Merck & Co’s best-selling cancer immunotherapy drug Keytruda, doctors and researchers say a far cheaper alternative could be available within two years when the drug’s patent expires in June 2028 — offering hope at a time when each mandated 200mg dose costs more than Rs 3 lakh.
“We have seen this with other immunotherapies. The entry of biosimilars leads to a significant drop in prices, sometimes by as much as 70%. This is the simplest way to make cancer drugs more affordable and accessible. In the long run, however, India needs to invest in developing its own therapies,” said Dr Tarun Durga, associate director of medical oncology, Medanta-Noida.
The lack of access to Keytruda is one of the key findings of an investigation by The Indian Express in association with the International Consortium of Investigative Journalists (ICIJ) into how a growing multi-city counterfeit racket in the drug is fuelled by a company mandate for standardised high dosing and an opaque patient programme.
According to minutes of expert committee meetings under the drug regulator, Central Drugs Standard Control Organization (CDSCO), and data from the country’s clinical trials registry, companies conducting trials or seeking approvals include Sun, Hetero and Intas, among others.
In January, Biocon said they would include three more cancer biosimilars to its portfolio, including pembrolizumab. Trials for generic versions developed by Chinese firm BioThera and Russian company Biocad are also underway in India.
Vials of counterfeit Keytruda seized by Delhi Police.
While Merck & Co (MSD) holds only one valid patent on the molecule pembrolizumab in India, it holds nearly 1,000 patents and patent families linked to it globally, with almost 84% filed after the drug’s first approval in 2014. The company is also seeking patents for a pre-filled pen and subcutaneous version of the drug in India.
“Biosimilar versions can enter the market soon after patent expiry, unless the company, which has deep pockets, takes them to court. This has happened with the other checkpoint inhibitor nivolumab as well… Although two secondary patents for pembrolizumab has been rejected by the Indian patent office, patent clusters around a molecule can be used to block biosimilar production even after the principal patent expires,” said K M Gopakumar, co-convenor of Working Group on Access to Medicines & Treatment, a coalition of activists, academics and patient right groups.
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Checkpoint inhibitors come under a class of drugs that remove the brakes preventing the body’s T cells, a crucial weapon in the immune system, from attacking cancerous cells.
In January, the Delhi High Court cleared the way for Zydus Lifesciences to manufacture and sell a biosimilar of nivolumab made by Bristol-Myers Squibb (BMS) — months before the patent is set to expire on May 2. In February, the Supreme Court dismissed a plea by BMS to block Zydus from selling the generic version.
Outside the medical oncology department of Nair Hospital in Mumbai. (Express photo by Nayonika Bose)
Significantly, in March, the Government announced Bio Pharma SHAKTI — a Rs 10,000-crore scheme to build a domestic ecosystem for biosimilars to reduce import dependence on high-cost drugs, with manufacturers asked to focus on cancer and autoimmune disorders.
Gopakumar said that with pembrolizumab now on WHO’s model list of essential medicines, India must “actively support” its biosimilar development. “Organisations such as BIRAC (Biotechnology Industry Research Assistance Council) should develop the cell lines and let several companies build their biosimilars on it. There is also a need to do away with clinical trials for biosimilars to establish safety and efficacy, in line with WHO and UK guidelines, and then bring these drugs under the national list of essential medicines to regulate prices,” he said.
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Excerpts from a purported WhatsApp chat between a supplier of fake vials and a pharmacist — both are in custody
Unlike standard drugs such as paracetamol, biosimilar developers must currently conduct full trials, adding significant cost and time. Experts say the trajectory of trastuzumab — a targeted therapy for a type of breast and stomach cancers that lost its patent in 2012 — illustrates the challenge. “It took several years for eight-nine companies to enter the market after which the price finally dropped to Rs 7,000 from Rs 1.15 lakh for the originator product,” said Gopakumar.
© The Indian Express Pvt Ltd
