The first effective oral weight-loss medications are expected to reach the market this year, marking a major milestone in obesity treatment, according to a research note published Sunday by Guggenheim Securities. Analysts say the development is only one part of what is shaping up to be a pivotal year for obesity drugs.
Pill versions of the blockbuster injectable GLP-1 treatments from Novo Nordisk and Eli Lilly are likely to enter the market in the first half of 2026. Meanwhile, the lucrative injection segment will continue to evolve, with upcoming study results on long-acting GLP-1 drugs designed for monthly dosing instead of weekly injections, as well as non-GLP-1 therapies from AstraZeneca, Pfizer, and Zealand Pharma.
The pharmaceutical industry is investing heavily in obesity drug development, fueled by multibillion-dollar acquisitions and an expanding pipeline of research programs, said Guggenheim analyst Seamus Fernandez. More than 2,300 clinical trials are currently recruiting patients, and the number of late-stage Phase 3 studies has nearly doubled over the past year to about 140.
Eli Lilly leads the field in research activity, with 69 active studies—47 of them in Phase 3—targeting more than a dozen biological pathways involved in weight regulation. Novo Nordisk ranks second in terms of research breadth, though Fernandez noted that the market remains wide open for additional competitors.
“Large, untapped markets with multi-blockbuster potential have captured the interest of investors and biopharma alike,” Fernandez wrote.
Investor attention in the near term will focus on the rollout of Novo Nordisk’s Wegovy pill, which received U.S. Food and Drug Administration approval three weeks ago, and the anticipated second-quarter launch of Eli Lilly’s oral drug orforglipron, pending FDA approval. Analysts will closely watch whether gastrointestinal side effects limit the commercial uptake of either pill.
Several other companies are expected to release Phase 2 trial data on obesity pill candidates in the first half of the year, including programs from AstraZeneca in partnership with U.S.-China startup Eccogene, as well as Structure Therapeutics.
New entrants may also seek to compete with Novo and Lilly by offering longer-acting alternatives to current weekly injections. In September, Pfizer acquired Metsera in a deal valued at up to $10 billion, driven largely by Metsera’s experimental monthly GLP-1 therapy and its complementary weight-loss compound, amylin.
Pfizer CEO Albert Bourla said at the J.P. Morgan Healthcare Conference that Phase 2 results for both the long-acting GLP-1 and amylin candidates will be presented at major scientific meetings later this year.
Even longer dosing intervals could emerge through RNA-interference technology, which suppresses the production of disease-related proteins at the cellular level. Early clinical data from RNA-interference obesity treatments have boosted shares of Wave Life Sciences and Arrowhead Pharmaceuticals, with additional results expected in 2026.
Despite the growing pipeline, Guggenheim expects GLP-1 drugs to remain the backbone of obesity treatment for the foreseeable future. However, amylins—an alternative drug class that may cause fewer digestive side effects—are gaining attention. Versions are being developed by Novo Nordisk, Eli Lilly, and a partnership between Zealand Pharma and Roche Holding.
In December, Novo submitted an FDA application for approval of CagriSema, a once-weekly injection combining Wegovy with an amylin. A regulatory decision could come later this year.
Zealand and Roche are scheduled to release Phase 2 data on their amylin candidate petrelintide in the first quarter. Additional results on long-acting amylins from Pfizer and AstraZeneca, as well as an oral amylin therapy from Structure Therapeutics, are also expected this year.
According to Fernandez, amylin-based treatments could open a new segment of the obesity market, particularly for patients who are unable to tolerate GLP-1 drugs.
