Following the expiry of semaglutide's patent on March 20, 2026, multiple generic launches by domestic companies reshaped India's GLP-1 market, which reached around ₹1,579 crore by March 2026. For Eli Lilly, whose Mounjaro had only recently become India's top-selling drug by value, the pressure arrived faster than most forecasts anticipated. This isn't a product-level disruption. It is a structural shift in how pricing power behaves once exclusivity ends, and India is making that shift visible in real time.
From Monopoly to Market Flood
The transition from a branded-dominant segment to broad generic availability happened not over quarters, but within weeks. Over 40 domestic drugmakers launched or are preparing to launch more than 50 generic versions in the Indian market following patent expiry. Companies including Sun Pharma, Dr Reddy's, and Natco moved almost simultaneously, introducing semaglutide at price points that put the branded originals under immediate pressure. At least five domestic drugmakers undercut the original branded price by up to 80% within the first weekend of availability. The market response was measurable almost immediately. Semaglutide's share in India's GLP-1 segment jumped to 33% in March from 25% the month before, a gain that came directly at the expense of tirzepatide, the active ingredient in Lilly's Mounjaro, whose share fell to 64% from 71%. A segment that had taken years to build shifted its competitive balance within a single month, driven almost entirely by affordability rather than any change in clinical preference.
Margins Under Pressure
The financial impact on Eli Lilly became visible in the monthly numbers. Tirzepatide recorded a decline of ₹21 crore in March compared to February, while semaglutide continued to grow. Lilly's value share in the GLP-1 segment declined to approximately 56% from higher levels in preceding months. Mounjaro remains the segment's leading brand, but the direction of travel has clearly changed. The deeper dynamic is one that goes beyond any single company's performance. When generics enter a price-sensitive market at a fraction of the branded cost, the market doesn't simply split; it reorients. Volume expands as access improves, but revenue per unit compresses. Multinationals are left navigating a choice that rarely has a clean answer: hold the price point and lose share, or follow the market and protect volume at the cost of margin. A diabetes specialist noted that while nearly 50% of his patients could benefit from GLP-1 therapies, only 5% are currently using them, a gap that affordable generics are beginning to close, but one that also illustrates how much of this market's growth potential sits in the affordability-constrained segment rather than the premium tier. For multinationals, clinical differentiation, delivery innovation, and physician relationship depth are increasingly what sustain value once price exclusivity is no longer available as a lever.
Conclusion
India is not an isolated case. By the end of 2026, semaglutide's core patents will have expired in ten markets, including Brazil, China, South Africa, Turkey, and Canada. The pattern establishing itself in India, rapid multi-player generic entry, immediate price compression, and a measurable shift in brand share within weeks is a reasonable reference point for how post-exclusivity competition will unfold across each of those markets. For pharmaceutical executives, the strategic question India raises is not whether this pressure can be avoided. It cannot. The more productive question is what a company's value proposition looks like once price exclusivity is no longer part of it and how early that thinking needs to begin before the patent clock runs out. At InsightSphere, we analyse macroeconomic shifts and their real-world impact on business strategy, capital markets, and global trade.