A Delhi High Court verdict on January 12 may have cleared the way for a significantly cheaper version of a blockbuster cancer therapy drug in India.The drug, Nivolumab, is effective against a range of cancers. Global pharmaceutical company ER Squibb and Sons, better known as Bristol Myers-Squibb (BMS), currently holds its patent in India. The patent expires in May.The High Court verdict, which took the public interest into account, will enable Indian pharma company Zydus Lifesciences to manufacture and sell a ‘biosimilar’ version of the drug that could be much cheaper. This is why the High Court ruled in favour of Zydus, and why it matters for patients in India.Why has Nivolumab been so successful in cancer therapy?To fight an infection, our bodies create proteins known as antibodies. Nivolumab is a monoclonal antibody drug which acts by enhancing the immune response to fight cancerous cells.Monoclonal antibodies are lab-produced antibody molecules that can restore, enhance, modify or mimic our immune systems. These are used for targeted cellular action.This is what makes the treatment protocol stand out from, say, chemotherapy, which targets cancerous as well as healthy cells.This form of treatment is called immunotherapy. Nivolumab is similar to another immunotherapy monoclonal drug called Pembrolizumab, marketed as Keytruda by Merck (also currently under patent protection in India).Story continues below this adThis class of drugs has changed the landscape of medical oncology, especially in the domain of lung cancers, improving duration and quality of life, says Dr Shashank Pandya, director of Gujarat Cancer Research Institute.It can be prescribed in multiple scenarios — after primary treatment such as surgery; when the cancer has spread to other cells and organs; or when chemotherapy or radiotherapy is given before surgery to reduce the size of the tumors.What makes Nivolumab special is the range of cancers it has proven to be effective against: lung, renal, head and neck, melanoma, urothelial, oesophageal and gastric cancers.BMS has been granted patents on the drug in more than 50 countries. The US Food and Drug Administration (FDA) has designated it as a “Breakthrough Therapy” by . This tag effectively meant that the FDA could work closely with the firm and expedite the drug’s development and rollout.The cost factorStory continues below this adNivolumab, sold under the brand name Opdivo outside India, and Opdyta in India, has seen significant commercial success. The sales of the patent-protected drug has helped BMS tide over the challenge from the larger generic drugs market.According to BMS, Nivolumab generated revenue of around $9 billion in 2023. Financial reports from 2025 suggest that the company has been making upwards of $2 billion in each quarter from the drug.In India, however, the price point has been a pain, making it unaffordable for most patients. While the Central Government Health Scheme covers immunotherapies, the PMJAY does not.Opdyta vials can cost between Rs 45,000 and around Rs 1 lakh per vial, depending on the dosage strength (40 mg to 100 mg). So, treatment costs can increase by Rs 2-3.5 lakh per month.Story continues below this adWith India pharma companies now making biosimilars, the cost can be cut to one-third or one-fourth the present cost. For example, Zydus, in its marketing material, has pegged the cost of Tishtha (its current branding Nivolumab) at Rs 3.86-6.46 lakh — for a year’s treatment.Administered intravenously, the most commonly used adult schedules of Nivolumab at present advises 240 mg every two weeks or 480 mg every 4 weeks.While drugmakers such as BMS have claimed in court that its pricing for the drug in India is “at a low end”, multiple medical oncologists suggest that this is usually the trend when patents are about to expire. At times, such subsidies are made possible by patient assistance programme schemes run by the drugmakers.The BMS case against ZydusIn 2024, BMS moved the Delhi High Court against Zydus. It alleged that the Gujarat-based drugmaker was all set to launch a biosimilar version of Nivolumab despite its patent being in force until May 2026.Story continues below this adThe patent was filed by BMS in India in 2005 and granted in 2020. One of the early arguments by BMS in 2024 was that they “only have a couple of years to benefit from the suit patent”.A single-judge bench of the High Court, on May 8, 2024, directed that Zydus should not place its products in the market without court permission.Why did the Delhi HC overturn the earlier ruling?The division bench of Justices C Hari Shankar and Om Prakash Shukla weighed in two key factors before ruling in favour of Zydus.One was public interest — Zydus claimed that its biosimilar drug “would be 70% cheaper”.Story continues below this adThe other was the fact that the patent was anyway expiring in around four months.The division bench said: “Where the product in question is a life-saving drug, the Court has to err in favour of public interest… Withholding such therapy from the public can cause untold and irreparable prejudice to lakhs of lives…”The division bench also took into account the fact that the single-judge bench had mapped product-to-product claim to arrive at a conclusion of prima facie patent infringement, instead of product-to-claim mapping.Product-to-product mapping involves comparison of the plaintiff’s patented product with the defendant’s product while product-to-claim mapping is a legal test where the infringement is decided on the basis of mapping the said infringing product to the original patent claims.