From Zepbound to Foundayo: Lilly's Latest Results Support Oral GLP-1 Outlook

Key Points

• Eli Lilly saw a huge gain after its recent earnings report, but the wins didn't stop there
• Lilly also recently got a boost after releasing strong results for its oral GLP-1, Foundayo
• The data provides evidence that Foundayo is effective in helping keep lost weight off, supporting an emerging growth vertical for Lilly

Shares of Eli Lilly and Company NYSE: LLY, the world’s most valuable pharmaceutical stock, started 2026 in a bad way. Near the end of April, LLY shares had fallen as much as 20%. However, the stock has rebounded mightily since then.

Lilly’s highly impressive earnings report kicked off the rally, with shares surging nearly 10% in one day. Lilly has continued to trudge higher, now down only around 5% in 2026.

One event that recently helped Lilly's stock move up was the latest results surrounding its oral GLP-1 medication Foundayo. While Foundayo is already approved by the Food and Drug Administration, the need to continue testing does not stop there. By generating more robust and a wider variety of data on the medication, Lilly can improve the chances of doctors prescribing it. Lilly’s latest results support this all-important goal.

Foundayo’s 2-Pronged Attack: Needle Fear Patients and Maintenance Patients

The trial in question focuses on weight-loss maintenance—helping patients keep lost weight off after they stop taking high-dose GLP-1s. For Lilly, this is part of a two-pronged strategy to generate demand for Foundayo.

The first part is based on attracting completely new patients. Researchers estimate that up to 25% of U.S. adults have a fear of needles, preventing certain patients who want to lose weight from taking injectable GLP-1s. Through pill-based medications, Lilly can unlock demand from this patient group.

However, Lilly is falling behind Novo Nordisk A/S NYSE: NVO on oral uptake, as Novo received approval for its oral weight-loss drug several months earlier. Novo’s pill has also demonstrated efficacy that moderately surpasses Foundayo. Novo notes an average weight loss of 14% after 64 weeks among patients taking the Wegovy pill. This compares to an average weight loss of 12.4% after 72 weeks for Foundayo.

According to BMO Capital Markets, “While Foundayo scripts have been trending upward since launch in April, scripts have lagged vs. those of the Wegovy Pill and Street expectations.”

However, Lilly may be able to better differentiate itself in the second prong of its strategy: weight loss maintenance. Injectables are more efficacious than either pill, with Lilly touting an average weight loss of 20.2% at 72 weeks for patients using Zepbound. Thus, after losing a lot of weight on injectables, patients can transition to pills in order to keep lost weight off.

With this, Lilly can drive recurring sales of Foundayo as patients make the switch. Its latest Foundayo results provided encouraging data on this front.

Foundayo: Weight Loss Maintenance Improves Dramatically Versus Going Cold Turkey

In its ATTAIN-MAINTAIN trial, Lilly looked at patients who had lost significant weight through taking Zepbound. Throughout the Zepbound period, patients lost an average of 55 lbs. Patients then transitioned onto Foundayo for 52 weeks, gaining back 11 lbs. So, when using Foundayo as a maintenance treatment, patients regained only 20% of their original weight loss.

This is actually a strong showing, as patients who get off GLP-1s completely regain much more weight. A recent analysis of 48 studies found that after one year of getting off GLP-1s, patients regained 60% of their original weight loss. Thus, the percentage of weight loss kept in Lilly’s study is three times higher than that of those who got off GLP-1s completely.

Lilly also performed the same test with patients who originally lost 41 lbs by taking injectable Wegovy. After switching to Foundayo for 52 weeks, these patients regained just 2 lbs—another very strong result. In the end, Zepbound to Foundayo patients lost 17.2% of their weight, and Wegovy to Foundayo patients lost 15.5% of their weight on average.

Clearly, these results provide evidence that transitioning to Foundayo after taking injectables can be an effective pathway for keeping lost weight off. Notably, on the day of this data release, Lilly's shares rose by 2.4%.

There is also reason to believe that Foundayo will have greater appeal as a weight-loss maintenance treatment than the Wegovy pill. This is because it comes with no dietary restrictions. Meanwhile, doctors advise Wegovy pill patients not to eat or drink for 30 minutes after taking the medication.

Ultimately, the convenience factor of pills is a key reason why people would want to switch from injectables. With no dietary restrictions, Lilly has an advantage here. However, it will be interesting to see if Novo conducts a similar maintenance study that could shift the playing field in this vertical.

Analysts Forecast Substantial Upside in Lilly After Recent Rebound

Overall, targeting the weight-loss maintenance market is one of many levers Eli Lilly can pull to continue growing its GLP-1 business. Notably, even with Lilly only down less than 10% from its all-time high, Wall Street analysts continue to forecast substantial gains ahead. The MarketBeat consensus price target on the stock sits near $1,218, implying upside of just over 20%.