The two companies at the centre of the weight-loss drug surge delivered sharply different messages in the past week.
Novo Nordisk (NYSE:NVO) on Wednesday reported quarterly results that missed market expectations and lowered its full-year profit outlook, citing higher investment in manufacturing and continued constraints on supply for Wegovy. Eli Lilly and Co (NYSE:LLY), meanwhile, posted another set of strong numbers last week driven by rising demand for Zepbound and Mounjaro and upgraded guidance for the year ahead.
Investors drew a sharp divide: Novo shares slipped about 4.2% after its guidance cut, while Lilly shares jumped about 10% on the back of its earnings beat.
The split in performance comes as the US government is exploring ways to expand access to GLP-1 drugs by reducing headline pricing — potentially through a pathway that would allow Medicare to cover obesity treatment if manufacturers agree to a lower monthly price. While discussions are early and no terms have been finalised, the possibility of a national reimbursement framework adds a new layer to what has so far been a commercially driven market.
Novo and Lilly are still selling everything they can make. But now, the conversation is shifting from demand to execution and economics.
Novo Nordisk: Growth still strong, but guidance steps down
Novo’s results show the company is still expanding, though not as quickly as analysts expected. Revenue climbed on continued uptake of Wegovy and Ozempic, but profit growth lagged due to heavy capital commitments to increase manufacturing capacity. Management reduced its full-year profit guidance, signalling that scaling GLP-1 production is proving more expensive and more complex than early investor enthusiasm implied.
The company acknowledged that supply remains the limiting factor, not demand. It also confirmed that its semaglutide products are included in upcoming US pricing negotiations under the Inflation Reduction Act — a reminder that pricing flexibility for GLP-1s may tighten over the coming years.
Shares traded lower as the guidance cut filtered through analyst models.
Eli Lilly: Strong demand, smoother trajectory
Lilly’s update last week told a different story. Revenue accelerated on strong uptake of Zepbound and Mounjaro, particularly in the US, and the company lifted its full-year guidance. Importantly, management said additional manufacturing capacity is flowing through the system, reducing lost prescriptions and supporting further growth.
Where Novo is working to close the gap between demand and supply, Lilly is beginning to use its excess supply to win prescriptions.
Investors rewarded the clarity of the message: strong demand, improving capacity, rising guidance.
Why the US pricing discussions matter now
The reports out of Washington come at a moment when the competitive dynamics between Novo and Lilly are widening. The proposal being discussed — a simplified monthly price that would enable Medicare reimbursement for obesity treatment — would shift GLP-1s from high-price, cash-pay demand to reimbursed, population-scale therapy.
Both companies would gain access to a far larger patient base.
But if lower pricing becomes part of the trade-off, scale becomes the determining factor.
- Novo’s results this week showed that capacity growth requires heavy spending and may constrain margins in the near term.
- Lilly’s showed that it is already entering the next phase — with more supply and a cleaner runway to absorb pricing pressure.
The takeaway
Demand for GLP-1 drugs remains extraordinary, but the narrative is changing.
- Novo Nordisk is still the category leader, yet now managing slower profit growth and significant investment.
- Eli Lilly is growing into its momentum, supported by manufacturing scale and rising guidance.
The obesity-drug boom is no longer just about who has the best molecule. It’s about who can meet demand at scale — and who can adapt if national pricing rules enter the picture.