The approval of Eli Lilly’s orforglipron, sold as Foundayo, has changed the discussion around oral GLP-1s. Until recently, the GLP-1 receptor was widely seen as a poor target for conventional small-molecule chemistry. Injectable peptides proved that the biology worked, but an oral small molecule that could deliver meaningful efficacy remained a much harder proposition. Foundayo’s approval on 1 April 2026 shows that this barrier can be overcome.

The commercial forecasts explain the excitement, Fidelity has put 2026 sales at $1.5bn to $2.8bn, Citi has forecast peak annual revenues above $40bn, and Clarivate projects $11.1bn in obesity sales across the G7 by 2031. After years in which the category has been shaped by peptide manufacturing constraints, injector supply and access problems, a tablet is an attractive prospect.

However, no sooner had the breakthrough been achieved, than thoughts moved to what the broader small-molecule GLP-1 agonist landscape will look like as it matures. Foundayo is unlikely to sit alone for long. If other programmes make it through the clinic, oral GLP-1s could become a genuine class rather than just a single blockbuster product. While this would change the commercial equation, it would also change the scientific and patent questions companies need to think about now.

Although no other applications for approval are currently pending and the successful completion of clinical trials is not a certainty, Foundayo will not be the only approved small-molecule GLP-1 agonist for long. Structure Therapeutics’ aleniglipron is one of the clearest frontrunners. Data from the ACCESS II trial published in June 2026 showed dose-dependent, clinically meaningful weight loss with continued reduction beyond 36 weeks, up to 16.2% during the open-label extension, alongside a favourable tolerability profile and an overall 10.4% discontinuation rate.

That places aleniglipron among the most efficacious oral GLP-1 candidates reported to date, and the company has received positive end-of-phase 2 feedback from the FDA and anticipates initiating its phase 3 programme in Q3 2026.

For executives, the take-home is straightforward: within roughly three years, the oral small-molecule subclass is likely to have multiple approved members rather than one. That is when genuine price competition arrives, first in cash-pay and lower-income markets, where injectable logistics and refrigeration costs have always been hardest to sustain, and then gradually into reimbursed markets as patients gain leverage from having alternatives. Boards positioning against this wave should be asking now whether their obesity and diabetes strategies shortsightedly assume a Foundayo-shaped monopoly, because that will not last forever.

Obesity is a multifactorial disease, which is one reason injectable GLP-1 development has moved towards drugs that act on more than one receptor. The injectable peptide solved the demand for greater efficacy through single-molecule multi-receptor agonism, with tirzepatide (GLP-1/GIP) and retatrutide (GLP-1/GIP/glucagon) being the clearest examples that were engineered as single hybridised peptide sequences.

Small molecules cannot easily follow that path; there is no obvious chemical analogue to sequence hybridisation, and balanced multi-receptor agonism is difficult to engineer into one compound. The small-molecule answer is instead likely to be combination therapy.

Structure Therapeutics is already pursuing oral amylin candidates, ACCG-2671 and ACCG-3535, for possible fixed-dose pairing with its GLP-1 programme. It is also working at an earlier stage on GIP, glucagon and apelin receptor agonists.

Amylin is especially interesting because weight loss is not simply about how much weight patients lose. The composition of that loss matters too; older patients, in particular, may be vulnerable to loss of muscle mass and sarcopenia. Combinations with other muscle-preserving compounds are also an attractive proposition, including myostatin inhibitors and activin receptor antibodies (such as bimagrumab), which work by blocking the signalling pathways that restrain muscle growth.

In Eli Lilly’s phase 2 BELIEVE trial, published in March 2026, bimagrumab combination groups showed a small increase above baseline in lean mass and largely preserved lean mass relative to semaglutide-only groups. Selective androgen receptor modulators are also of interest to promote anabolic activity with fewer side effects than traditional androgens, such as testosterone.

For pharma companies, this means that the next race may be about assembling the right pairing, rather than squeezing every possible benefit out of a single molecule.

It also matters for corporate development: expect more licensing deals structured around backbone-plus-partner combinations, such as some that have recently been reported where there is an upfront deal relating to the backbone GLP-1 drug with milestone payments and royalties that will take into account, among other things, any successful combination therapies. Executives building or evaluating obesity and cardiometabolic pipelines should treat combination-readiness, not just monotherapy data, as a due-diligence criterion.

The least resolved issue for this drug class is arguably hepatic safety. Pfizer’s experience is the cautionary tale: danuglipron and lotiglipron, despite sharing biased Gs signalling and oral bioavailability with orforglipron, were both discontinued after drug-induced liver injury signals. That outcome challenged foundational assumptions about safety prediction in small-molecule GLP-1RA design, since biased agonism does not appear to confer protection against off-target hepatic effects.

Orforglipron’s own record so far is reassuring, but not yet definitive. Lilly’s ACHIEVE-4 trial included a thorough analysis of potential drug-induced liver injury, and the analyses confirmed there was no hepatic safety signal, consistent with all prior studies in the ACHIEVE and ATTAIN programmes. Regulators, however, are not treating the question as closed. The FDA’s approval letter required Eli Lilly to submit adjudicated cardiovascular safety data and a full DILI (drug-induced liver injury) assessment. A subsequent isolated liver-failure case captured in the FDA’s adverse event reporting system drew media attention, even as the company and independent analysts urged caution against over-interpreting a single report.

The commercial stakes here are asymmetric and difficult to plan for. A second confirmed hepatotoxicity signal on any approved small-molecule GLP-1 might not just affect one product, it could more broadly recalibrate the regulatory and commercial framework for the entire subclass, exactly as it did for Pfizer’s programme.

Taken together, the three waves point to a small-molecule market that will look quite different from the peptide-dominated GLP-1 landscape of the past two decades: more entrants, more combination products and a yet-to-be-resolved safety overhang that has already ended two major development programmes. This has direct implications for how companies protect and extend value. Small-molecule composition-of-matter patents are built on classical generic Markush claims around a much larger serviceable chemical space than peptide sequences ever occupied, which means the intellectual property contest in this category will often be broader and more heavily contested than anything the peptide GLP-1s have faced.

Novo Nordisk’s recent patent infringement litigation against compounding platforms over semaglutide, with an asserted patent not expiring until December 2031, is an early indicator of how aggressively originators will defend their market share as competition intensifies. Small-molecule players should expect a similar, likely more crowded, contest to unfold around composition, crystalline form, process and combination patents over the next decade.

The companies that treat this as three separate, sequential problems – approval, differentiation and safety – rather than one continuous strategic challenge, are the ones most likely to be reading their own blockbuster forecasts in 2031, rather than someone else’s.