Where the blockbuster weight-loss drug market stands today — and what’s coming next

The market for injectable weight-loss and diabetes therapies continues to expand rapidly, driven by intense demand, ongoing supply scaling and a pipeline of competitors that could reshape access and pricing. Eli Lilly and Novo Nordisk remain the dominant suppliers, with Eli Lilly reporting market share gains through its third-quarter results; the company said its products now account for nearly six of every ten prescriptions within the injectable GLP-1 class. Despite broad momentum, the sector’s ultimate reach will hinge on factors such as insurance coverage, pricing strategies, the spread of compounded alternatives and the successful development of oral candidates.

Eli Lilly has built a lead in recent quarters, consistently increasing share while both firms scale production and pursue new clinical indications for their medicines. A wide range of pharmaceutical and biotech firms are pursuing the obesity market, and some analysts project a U.S. patient population of 25 million to 50 million users by 2030, implying a global market that could approach roughly $100 billion by decade’s end. Yet most experimental therapies remain several years from approval, and their commercial prospects will depend on confirmatory trial results and tolerability profiles.

Eli Lilly’s recent gains have cost Novo Nordisk ground, particularly in the U.S., where manufacturing disruptions, the rise of compounding and Eli Lilly’s clinical momentum have shifted prescribing patterns. Eli Lilly’s tirzepatide-based medicines outperformed in head-to-head and real-world comparisons, and the company reported sequential share growth—53% in the first quarter and roughly 57% in the second—helping explain investor rotation away from Novo Nordisk, whose shares have declined materially this year. Market watchers have pointed to weaker-than-expected data for some of Novo Nordisk’s pipeline assets and a slower commercial response to compounding as additional headwinds.

Novo Nordisk has responded with executive changes and workforce reductions, and it also faces longer-term pressure from impending Medicare price negotiations on semaglutide beginning in 2027. Eli Lilly’s tirzepatide portfolio is not scheduled for similar federal pricing reviews until later in the decade, which could influence competitive dynamics.

Compounded versions of GLP-1 medicines emerged when branded injections were constrained, and they remain a persistent regulatory and commercial issue. Although the FDA has declared shortages over and set limits on compounding for certain products, some mass compounding pharmacies continued to supply large volumes, and industry estimates suggest around 1 million U.S. patients have used compounded GLP-1s. Both Eli Lilly and Novo Nordisk have taken legal and commercial steps to restrict unauthorized copies, but enforcement has been uneven and the FDA’s approach to imported active ingredients has at times been permissive, complicating efforts to fully stem the flow of copycats.

Insurance coverage remains uneven, particularly for obesity indications; many payers cover GLP-1s for diabetes but not for weight management. Employer adoption has edged higher—surveys show roughly one-third of firms now offer coverage for these drugs—but concerns persist about cost, duration of therapy and workforce churn. Direct-to-consumer discount programs from manufacturers have improved affordability for cash-pay patients, and the U.S. administration’s experiments with broader Medicare pilots could expand access for older Americans. Still, payers are experimenting with controls such as BMI thresholds and other utilization limits to manage plan costs.

Oral GLP-1s are advancing through late-stage testing and could materially broaden the pool of patients willing to try pharmacologic therapy. Novo Nordisk’s oral semaglutide and Eli Lilly’s small-molecule candidate orforglipron both show promise, and some projections assign daily pills roughly a quarter of the market for weight-loss therapies by 2030. However, clinicians and analysts caution that pills may not match injectable efficacy and tolerability for many patients, and switching from injectable to oral regimens could risk partial weight regain. Manufacturing ease and dosing convenience are advantages for small-molecule approaches, but final positioning will depend on head-to-head performance and price.

A next wave of treatments—targeting different gut hormones such as amylin, or offering less frequent dosing—could diversify choices for patients and physicians. Amgen, for example, has advanced a monthly-dosed candidate into late-stage trials with mid-stage data showing notable weight reductions for some participants, albeit with elevated discontinuation rates. Larger pharma companies are also securing rights to investigational assets from international developers, and many smaller U.S. biotechs face a strategic decision point: pursue standalone development or partner with established players.

The obesity-drug market is set for continued expansion, but how broadly therapies penetrate will be determined by payer policy, pricing, the regulatory and legal environment around compounding, and the clinical performance of new oral and injectable entrants. For now, Eli Lilly leads the injectable segment while Novo Nordisk adjusts strategy and corporate structure to defend its position. Investors, clinicians and policymakers will be watching clinical readouts, reimbursement changes and the pace at which lower-cost or more convenient options reach patients—any of which could materially reshape market share and access over the next several years.