Elon Musk just dropped a bombshell about losing weight. The Tesla (NASDAQ: TSLA) CEO and Space Musk’s endorsement underscores the skyrocketing demand for GLP-1 inhibitors, drugs that were originally intended to treat diabetes but are now the hottest drug in weight loss treatments. Novo Nordisk (NYSE:NVO) and Lilly are at the top, with annual sales in the category expected to reach $150 billion by 2033. But here’s the twist: A growing flood of cheaper, licensed copies from countries like Bangladesh and Russia could put things in jeopardy for these pharmaceutical giants.

Just last week, a Reuters investigation found that a growing wave of semaglutide and tirzepatide copycats is affecting markets with looser patent rules. These generics are no joke and cost just $3 per month in Bangladesh, compared to $935.77 in the US. This is a huge gap, and it’s not just a niche problem. With patents expiring in countries like China and India by 2026, the clock is ticking for Novo and Lilly to defend their turf. While demand is currently outstripping supply, experts warn that increasing competition could push prices down faster than expected, particularly in emerging markets.

For investors, this market is a double-edged sword. The growth story here is undeniable. Global obesity rates mean unprecedented demand, but margin pressure from cheap generics cannot be ignored. Novo and Lilly increase production to maintain their lead, but the game is changing quickly. With over a billion people worldwide considered obese, it’s not just about profits, it’s about staying ahead in a market that’s redefining the future of healthcare and potentially your portfolio.

This article first appeared on GuruFocus.