Consensus is that tirzepatide (Zepbound / Mounjaro) will be the biggest drug of all time, topping $70B in sales by 2030. But, unlike other durable mega-blockbusters like Keytruda ($30B+) or Humira ($20B), this revenue has largely been unlocked by just one indication - obesity.

This means it was done early enough that tirzepatide still has 12 YEARS of patent life left, despite clear visibility to be 2.5x bigger than any drug we've seen before.

Of course, there will be other indications that support that $70B topline - T1D / T2D, sleep apnea, CV risk, CKD etc. And if the Alzheimer's studies readout positively, that figure could be way higher. But, the vast majority is driven by a belief that Lilly will dominate obesity - in fact, those supplementary indications' greatest contribution might be to facilitate payor reimbursement.

Lilly's overall revenue will exceed $100B by 2030 which offers an immense amount of operating leverage. On an absolute $ basis, you'll be leading the industry in R&D spend, but from a % perspective, you've actually improved the overall margin profile. Consensus has operating margins exceeding 50% by 2029 from ~32% in 2024.

Of course, Lilly will keep investing in current and next-gen assets for the obesity market, but they don't need to run thousands trials like Merck did for Keytruda to unlock tirzepatide's full potential.

So what does that do for a business usually focused on replacing upcoming patent expiries?

• They can invest in higher risk and longer-term R&D. 12+ years of visible growth means they can afford to focus on what the portfolio can look like in 2035 and beyond
• They don't have to splurge on near-term acquisitions to bolster revenue or chase what's hot today, like their Pharma peers that will (on average) have ~40-50% of the pipeline exposed to near-term LOEs, with some outliers like BMS and Merck over 90%
• It allows for creative BD structures. It makes sense why they partnered with a16z on a new venture fund

And when that LOE does eventually come, Lilly will have had over a decade to dull the impact by transitioning patients to next-gen obesity assets and nurturing a broad early-stage pipeline across the rest of their portfolio.