The Peptide Market Update: A Two-Drug Story Starts to Widen
For the past few years, the peptide story has mostly been told through two drugs: Novo Nordisk’s semaglutide (Ozempic, Wegovy, Rybelsus) and Eli Lilly’s tirzepatide (Mounjaro, Zepbound). They still dominate. But in the span of three days this October, a weight-loss pill entered late-stage trials, the FDA sent the White House a proposal that could loosen rules on experimental peptides, and a rare-disease treatment won a key European endorsement.
These are very different businesses with very different risks, and we don’t think they should be lumped together. But they point in the same direction: peptides are spreading into new diseases, new delivery formats and the manufacturing and testing businesses behind them. That broadening is the story to follow.
At a Glance
October at a Glance
Peptides are the body’s chemical messengers.
Peptides are short chains of amino acids (think of them as small proteins) that the body uses as chemical messengers. Insulin and GLP-1 are both peptides, and drugs built on them can mimic or strengthen those natural signals.
FDA and Compounding
A proposal now under White House review could let qualified pharmacies make certain experimental peptides. It’s a potential new market, but it is not a drug approval.
GLP-1 Sales
Lilly’s and Novo’s leading franchises generated about $71 billion in 2025. The demand is proven; the open question is who else profits from it.
Ascendis Pharma
A positive European opinion for TransCon CNP, a once-weekly treatment for achondroplasia. A final decision is expected this quarter.
Viking Therapeutics
Phase 3 trials of a daily weight-loss pill are under way. The big test is whether a pill can compete with injections.
Washington Opens the Door, Partway, to Experimental Peptides
On October 15, the FDA sent a proposed interim policy on peptide access to the White House Office of Management and Budget, a standard review step before many federal policies are released. According to Reuters and the Associated Press, the proposal could allow qualified compounding pharmacies (pharmacies that prepare customized medications) to make certain peptides on a temporary basis without facing FDA enforcement. As of October 20, the policy had not been finalized or published in full.
The groundwork was laid in July, when the FDA’s Pharmacy Compounding Advisory Committee reviewed several experimental peptides, including forms of BPC-157, TB-500, MOTS-c and KPV. According to reporting at the time, the committee recommended easing restrictions on six of the seven substances it reviewed. Those recommendations are advice, not binding decisions.
Here’s the part investors shouldn’t miss: permission to compound is not the same thing as drug approval. Peptides like these are often promoted for recovery, inflammation, metabolism or longevity, but the human evidence behind those claims is often thin. If the FDA chooses not to act against certain compounding, that says nothing about whether a substance is safe or effective, and it wouldn’t let anyone market it as an approved medicine.
Supporters argue that regulated pharmacies beat the status quo, in which many buyers turn to unverified online sellers. Critics point to risks around manufacturing quality, contamination, inconsistent dosing and the lack of solid clinical data. Both arguments have merit. The AP cited estimates of $2 billion to $3 billion for this market, though it’s hard to measure.
This development has the widest range of possible outcomes of anything this month. If the policy holds, it could open real opportunities for ingredient makers, testing labs and compounding pharmacies that can meet quality standards. But this is a policy bet, not a product bet. How much it’s worth depends on which substances are covered, which pharmacies qualify, the fine print on enforcement and whether an interim policy becomes a lasting one. We’d treat it as a separate, more speculative corner of the market, not an extension of the FDA-approved drug business.
Two Drugs, $71 Billion, and the Question That Matters More
If anyone doubts that peptides are big business, the numbers settle it. According to the companies’ 2025 annual disclosures, Eli Lilly’s Mounjaro and Zepbound brought in about $36.5 billion combined. Novo Nordisk’s semaglutide family (mainly Ozempic, Wegovy and Rybelsus) generated sales in the mid-$30 billion range in U.S. dollars, depending on the exchange rate used. Together, that’s roughly $71 billion in a single year, a scale rarely reached by any single area of medicine.
Two caveats keep that figure in perspective. It covers these specific products, not the whole peptide drug market. And the growth behind it reflects pricing, product mix, insurance coverage and expansion into new countries, not just more prescriptions.
Be wary, too, of eye-catching forecasts built on how many people could qualify for obesity or metabolic treatment. We’d read those as scenarios, not predictions. Real demand depends on cost, insurance, prescribing, side effects, whether patients stay on treatment and whether manufacturers can keep up.
The more interesting action may be behind the scenes. Every dose has to be made, filled and packaged, and rising volumes could support investment in peptide manufacturing, fill-finish (putting sterile drug into vials, syringes and pens), delivery devices, quality control and contract manufacturing. How much any one supplier benefits will depend on how full its plants are, its patents and know-how, its pricing power and how much it leans on a few big customers.
Demand for metabolic drugs is well established. The more useful question now is who earns money from it, and how much. We think the economics (margins, capacity and contract terms) will tell investors more than any headline estimate of market size.
Ascendis Shows There’s More to Peptides Than Weight Loss
On October 16, Ascendis Pharma (ASND) said the European Medicines Agency’s scientific committee, known as the CHMP, had recommended approval of TransCon CNP (navepegritide) for children aged two and older with achondroplasia whose growth plates have not yet closed, meaning they are still growing. Achondroplasia is a genetic condition and the most common cause of dwarfism. The European Commission makes the final call, with a decision expected in the fourth quarter of 2026.
TransCon CNP is a prodrug, an inactive form of a medicine designed to release the active drug gradually in the body. Here, that’s C-type natriuretic peptide (CNP), a natural signal involved in bone growth, delivered with one dose a week. For families giving a young child regular injections, fewer doses could make a real difference.
A committee recommendation is a major step, and the Commission typically follows the CHMP’s advice, but it isn’t final approval. After that, success will depend on doctor adoption, reimbursement, competition and how much families value the weekly schedule. Ascendis expects to launch first in Germany in the first quarter of 2027, if the treatment is authorized.
This is a useful reminder that peptides aren’t only about obesity and diabetes. Some of the most attractive opportunities may be differentiated treatments for well-defined, smaller patient groups with a clear medical need. For Ascendis, the questions to watch are straightforward: does final approval arrive on schedule, how well does the launch go, and how many eligible patients actually start treatment?
Obesity Pipeline
Viking Takes Its Weight-Loss Candidate Into Pill Form, and Into Phase 3
On October 14, Viking Therapeutics (VKTX) launched SUNRISE, its Phase 3 program for an oral version of VK2735. Phase 3 is the final, large-scale stage of testing before a company can apply for approval. VK2735 is an investigational drug designed to act on two hormone receptors, GLP-1 and GIP, the same dual approach behind Lilly’s tirzepatide.
The program includes two randomized, placebo-controlled studies, each aiming to enroll 560 participants and testing a once-daily pill over 68 weeks. One study includes adults with obesity or overweight who don’t have type 2 diabetes; the other includes adults with type 2 diabetes.
The injectable version has already produced encouraging data. In September, Viking reported 22% placebo-adjusted weight loss at week 33 for a weekly-dosing group (that is, after subtracting the change seen in the placebo group), along with early signs that some participants kept much of the weight off on less frequent maintenance doses. One caution: those results come from the injection, not the pill now in Phase 3, and they don’t tell us how the oral version will perform.
Why a pill? Many people would rather swallow a tablet than take a shot, and in a market this large, convenience could be a real edge. But neither a pill nor a less frequent injection wins automatically. Each still has to show competitive weight loss, tolerable stomach-related side effects, practical manufacturing, workable dosing rules and insurer coverage, all while competing with established treatments.
Viking now has two shots on goal, a pill and an injection, each with its own clinical and commercial questions. That gives the company more flexibility than a developer betting on a single product. But with 68 weeks of treatment still ahead, Phase 3 results are well over a year away, and approval, differentiation and market share all remain open questions.
Company Check-In
Where Things Stand
Next milestone: the European Commission’s final decision on TransCon CNP, expected this quarter, with a German launch planned for early 2027 if approved.
Phase 3 trials of oral VK2735 are now under way. The central question is whether a daily pill can compete with today’s leading treatments.
Mounjaro and Zepbound generated about $36.5 billion in 2025 sales. With demand established, the focus shifts to keeping volume growing, managing net prices (what Lilly keeps after discounts and rebates) and setting its next generation of treatments apart.
Posted substantial 2025 sales across Ozempic, Wegovy and Rybelsus. Competition, patient access and how its pill and injection lineup evolves will shape the outlook.
Offers exposure to oral peptides outside of obesity. Its drug ICOTYDE (icotrokinra), approved by the FDA in March 2026 for eligible patients with moderate-to-severe plaque psoriasis, is sold by Johnson & Johnson. Protagonist earns milestone payments and royalties rather than booking all product sales itself, so its results are closely tied to how well J&J executes.
A specialized manufacturer that makes peptides for drug companies, giving it a supplier’s seat in this market’s growth. The numbers that matter: how full its plants are, how quickly new facilities are qualified, what customers commit to and whether spending on expansion stays disciplined.
Where Does the Money Actually End Up?
October made one thing clear: peptides are no longer just a two-drug story.
Approved medicines are generating enormous sales and attracting new competitors. At the same time, regulators are rethinking how some experimental peptides can be compounded, without lowering the bar a medicine has to clear to prove it is safe and effective.
That widening is what makes this an interesting moment, and a more complicated one. Rare-disease drugs, oral and longer-acting formats, and peptide manufacturing and testing are all part of the opportunity, but each has its own risks, barriers to entry and profit potential. Overall market growth won’t reward them equally.
The question we’d keep asking is simple: where does the money actually end up? It could flow to companies with standout clinical data and strong patents, to manufacturers with scarce, qualified production capacity, or to suppliers that make drugs easier and more reliable to take. The answer will come from trial results, regulatory decisions, pricing, manufacturing costs and competition, not from peptide market growth alone.
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