Lilly commits up to $650 million to Juvena for muscle-boosting drugs

Eli Lilly has agreed to pay Juvena Therapeutics an upfront fee plus more than $650 million in milestone payments to search for drugs that improve muscle health and body composition ^[1]. The partnership will use Juvena's artificial-intelligence-enabled screening platform, which maps proteins secreted by stem cells to specific disease effects, combining a database, computer modeling, and lab testing on human cells ^[1].

This is the third Lilly deal aimed at muscle preservation during incretin treatment, a category that includes drugs like Zepbound (tirzepatide) ^[1]. Interest in muscle-boosting drugs has grown alongside demand for GLP-1 medicines, because these drugs cause people to lose lean mass along with fat ^[1]. Losing lean mass could, in theory, affect physical function and raise the risk of falls and fractures, especially in older adults ^[1].

Under the agreement, Lilly holds an exclusive license for lead drug candidates against multiple biological targets that Juvena's platform identifies ^[1]. Lilly will decide whether to advance any program only after Juvena hits certain milestones; if Lilly moves forward, its own teams take over research, development, and commercialization ^[1]. Juvena has already used its platform to find JUV-161, a fusion protein designed to help muscle regenerate, and recently started a first-in-human trial of that molecule in myotonic dystrophy type 1, a disease affecting skeletal and smooth muscle ^[1].

The Juvena deal builds on Lilly's earlier $1.92 billion purchase of Versanis Bio in 2023, which gave Lilly bimagrumab, an antibody that blocks a receptor to stimulate skeletal muscle growth ^[1]. Lilly expects data later this year from a phase 2 trial testing bimagrumab alongside semaglutide, Novo Nordisk's GLP-1 drug marketed as Ozempic and Wegovy ^[1]. Lilly has also started phase 2 trials combining bimagrumab with its own tirzepatide ^[1].

Why it matters for patients

People taking GLP-1 drugs for weight loss lose both fat and lean muscle mass, and researchers are still working out how much that muscle loss matters for daily function, strength, or fracture risk ^[1]. Lilly's chief scientific officer, Daniel Skovronsky, said on a February earnings call that the company will likely need to see either extra weight loss or a clear functional benefit from preserving lean mass, because lean mass changes alone are hard to interpret ^[1]. He also said Lilly has not seen signs that lean mass changes from tirzepatide, or any incretin drug, are harmful ^[1]. That means the muscle-preservation drugs described here are still experimental and years from being available; nothing in this deal changes what current GLP-1 users should expect from their existing prescriptions.

Lilly is not alone in targeting this niche. Roche paid $2.7 billion to buy Carmot Therapeutics for obesity drug candidates, and Regeneron paid Hansoh Pharma $80 million for a GLP-1/GIP receptor drug, as both companies try to combine obesity treatments with muscle-focused candidates to compete against Lilly and Novo Nordisk ^[1].

What happens next

Lilly expects phase 2 trial results this year testing bimagrumab combined with semaglutide ^[1]. The company has also launched phase 2 trials pairing bimagrumab with tirzepatide, though no timeline for those results was given in the available reporting ^[1]. Under the Juvena partnership, any specific candidates will only advance toward development after Juvena's platform hits agreed milestones, and no target molecules or trial timelines have been named yet ^[1].