What’s Keytruda, why is it a big deal in India’s cancer fight

Keytruda is the brand name of pembrolizumab, an immunotherapy drug manufactured by US-based global pharma major Merck & Co (MSD) for treating several cancers. It belongs to a class called “checkpoint inhibitors” — drugs that remove the brakes preventing the body’s T cells, which are a crucial weapon in the body’s immune system, from attacking cancerous cells. In other words, it uses the body’s own immune system to fight cancer.

Pembrolizumab works by attaching to receptors called PD-1 on T cells. This prevents T cells from binding with corresponding PD-L1 receptors on cancer cells, letting them identify the abnormal cells and triggering an immune response.

First approved by the US FDA in 2014 for advanced skin cancer, Keytruda is now used globally for certain lung cancers, cervical cancer, renal cell cancer and aggressive breast cancer, among others. It is the best-selling drug globally, generating $29.5 billion in 2024 — nearly half of Merck & Co’s revenue.

Keytruda is part of immunotherapy — an umbrella term for treatments that train the immune system to tackle disease, primarily cancers. It is a part of cancer treatment that also includes radiotherapy, chemotherapy, and if needed, surgery.

How is immunotherapy different from chemotherapy and radiation?

While chemo and radiotherapy directly kill cancer cells — and some healthy cells along with it — immunotherapy pushes the body’s own immune system to recognise and kill cancer cells. Being highly targeted, immunotherapy spares healthy cells. Importantly, it has shown some remarkable results in late stage cancers, with tumours disappearing completely in some patients. These therapies have been shown to extend life even in patients with aggressive forms of cancer.

What is Keytruda’s place in the category of immunotherapies?

Keytruda belongs to the category of monoclonal antibodies, which are laboratory-made molecules designed to bind with specific targets, enabling the immune system to identify and destroy cancerous cells.

The other important immunotherapy treatments are:

* CAR-T cell therapy involves collecting a patient’s own T cells, engineering them to create chimeric receptors, multiplying these modified cells, and returning them to the patient. These engineered T cells can then identify, attach to, and destroy cancer cells that would normally evade immune detection.

* mRNA vaccines for cancer are currently under development. Unlike vaccines for infections given to healthy individuals, cancer vaccines are administered to patients who already have certain cancers to prevent relapse. These vaccines train the immune system to identify proteins called neoantigens found only in cancer cells. Once recognised, the immune system remembers these markers for years, continuing to fight cancer and prevent recurrence.

Are immunotherapies available in India?

Several monoclonal antibodies, including Keytruda, are available in tertiary care hospitals across India. Generic versions of some monoclonal antibodies exist, including trastuzumab and nivolumab, another PD-1 checkpoint inhibitor.

CAR-T therapy remains cost-intensive and technology-driven. ImmunoAct, an IIT-Bombay incubated startup, developed India’s first indigenous CAR-T therapy called NexCar19, currently the most readily available option in the country.

What does Keytruda cost in India? What’s the standard dose? How does one get it? What kinds of health insurance cover it? Do specialised cancer care policies cover it?

Merck & Co’s recommended dosage is 200 mg every three weeks. With every 100mg vial marketed at a price upwards of Rs 1.5 lakh, patients without health coverage or assistance schemes would have to spend over Rs 3 lakh every month.

Most patients in India, therefore, get the drug through the company’s Patient Access Programme. This programme provides patients with 30 free vials on purchasing five initially for a total cost of around Rs 10 lakh. Patients may use a third-party health insurance to pay for the initial dose. Accessing the drug through the programme has some stipulations — the patient should not have a sum-insured or income of over Rs 25 lakh.

 

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While general health insurance policies may provide limited cover for these therapies, there are specialised cancer care policies that are designed to pay for these expensive drugs. Patients may also access the treatment through certain Government health schemes such as CGHS.

Why is Keytruda so expensive? Is a cheaper version coming?

Drugs such as Keytruda are monoclonal antibodies, which are more complex to manufacture than small-molecule medicines, such as Paracetamol. Yet, most costs arise from patent rights. Keytruda’s patent expires in 2028, with several companies already developing generic versions, which could bring down costs by up to 70%.

Why is India important for Merck in the Keytruda market?

With one of the largest populations in the world and a rising cancer burden, access to immunotherapies in India remains largely constrained by cost. Although India’s cancer incidence rate is currently below the global average, it is climbing steadily. The latest Global Burden of Disease estimates indicate that the rate of cancer occurrence rose from 84.8 per 100,000 population in 1990 to 107.2 per 100,000 in 2023.

Data from the WHO’s Global Cancer Observatory shows that India recorded 14.13 lakh cancer cases in 2022, a figure projected to surge by 73.8% to 24.56 lakh cases by 2045. The GLOBOCAN database puts India’s current incidence at 98.5 per 100,000. By contrast, Australia, which has one of the world’s highest incidence rates at 462.5 per 100,000, is expected to see a comparatively modest 49.9% increase by 2045, with absolute case numbers rising from 2.12 lakh in 2022 to 3.18 lakh by 2045.

In this context, to make Keytruda more affordable, the Government decided to do away with basic custom duty on the drug last year. Union Finance Minister Nirmala Sitharaman said in her Budget speech last year that Keytruda and its patient access programme were among the 36 drugs and 13 such programmes exempt from the duty.

What is the key finding of The Indian Express investigation?

Cancer Calculus, the investigation by The Indian Express in association with The International Consortium of Investigative Journalists (ICIJ), found an alarming rise of a counterfeit market in Keytruda fuelled by lack of access for most patients, and use of standardised high dosing that increases costs. It found hospital-level breaches and insider involvement, glaring loopholes in the system and how police investigators have unearthed evidence linking hospital staff to the counterfeit supply. The investigation exposes a broader systemic failure involving high drug prices, regulatory gaps and compromised hospital oversight.

For a patient who needs Keytruda and can access it, how do they ensure they are getting the genuine vial and not a counterfeit version?

The challenge is that counterfeit Keytruda is sold in genuine vials and packaging, making it very hard even for the trained eye to make a distinction. The best way to ensure that the product is genuine is to purchase from a hospital pharmacy — these drugs are mostly sold directly to the hospital by licensed distributors. Getting the drug through the patient access programme also ensures that you get genuine products.