Biopharma’s obsession with the weight loss sector—projected to exceed $130 billion in revenue by 2035—shows no signs of slowing down as analysts gear up for a year that will test the oral market and provide key data on novel mechanisms.
A month into 2026, the GLP-1 space continues to drive buzz across biopharma. Much of the recent discussion has centered on oral therapies—most notably, the so-far successful launch of Novo Nordisk’s oral Wegovy. Next-gen weight loss drugs such as Pfizer’s Metsera-acquired assets have also made recent headlines. Everyone is vying for a piece of a market already valued at north of $50 billion and expanding rapidly.
Making predictions in the obesity space has proven especially tricky, BMO Capital Markets analyst Evan Seigerman told BioSpace. “Obesity is a unique medical condition, [with] a unique set of challenges to help investors and others understand what’s real, what’s not real, what’s actually happening, and how these drugs actually help patients.”
Complicating matters is the question of access, Seigerman said, particularly noting the failure of Congress to renew healthcare subsidies under the Affordable Care Act in December and January.
“[This] laid bare some of the larger issues that we have in the system,” he said. “Premiums have been increasing, but they’ve just been hidden by subsidies and government workarounds.” The growing self-pay market for Wegovy (semaglutide) and Eli Lilly’s rival injectable Zepbound (tirzepatide), as well as the Trump Administration’s efforts to negotiate lower out-of-pocket costs, have made GLP-1s the poster child for systemic issues, he added.
These issues will take legislation and time to play out, and their influence on the future weight loss market for now remains an open question. In the meantime, the clinical race carries on. Here, BioSpace takes a deep dive into what to expect in the obesity sector this year, from oral therapies to amylin to the regulatory picture.
Next-Gen Weight Loss Drugs: Age of Amylin?
The first amylin-based drug for obesity could hit the market this year, after Novo in December filed for FDA approval of CagriSema. A combination of semaglutide and cagrilintide that targets amylin and calcitonin receptors, CagriSema has a distinct mechanism of action, but Novo is only one of several companies developing drugs that interact with amylin.
“Amylin is going be an important target,” Seigerman said. “There are still patients who don’t respond well to GLP-1s, so we do need alternative targets.” He noted that Pfizer will also share data in the first half of 2026 for its amylin analog, MET-233i, picked up in its recent Metsera acquisition.
Meanwhile, Lilly presented Phase II data on its own amylin receptor agonist, eloralintide, as a monotherapy in November last year, showing up to 20% weight loss after 48 weeks.
“Eloralintide was shown to have a much better gastrointestinal side effect profile than GLP-1s, and that’s what made it special,” Leerink Partners analyst David Risinger told BioSpace. He expects to see data sometime this year from a combination trial of eloralintide and tirzepatide.
“We’re looking forward to this combination study on top of tirzepatide to learn more about its potential to offer additional weight loss, and also to learn how Lilly will develop the two in combination in Phase III trials going forward,” Risinger said.
Lilly is hot on Novo’s tail with its own oral offering, orforglipron. While an FDA decision had been expected in March after the product was granted expedited review under the new Commissioner’s National Priority Voucher program, it now appears the company will need to wait a few weeks longer.
Will Orals Face Off? Decision Delayed for Lilly’s Orforglipron
“FDA had made promises for ultrafast reviews, but it’s already delayed some action on certain products,” Risinger said. “Lilly is targeting a launch in the second quarter, but neither the FDA nor Lilly has provided a PDUFA date.”
The new target action date for orforglipron is April 10, Reuters reported on Jan. 15, citing internal regulatory documents it was able to review.
Whenever Lilly receives a decision, it will be playing catch-up behind Novo but will likely gain market share quickly. “We do expect there to be significant patient demand for oral products,” Risinger said.
Seigerman is less certain about the impact oral alternatives will have on the market. The assumption has been that needle-phobic patients will drive a shift to pills over self-injections, but he noted that factors like dosing frequency, side effect profiles and maintenance therapy routine might be more important.
“I think maintenance is what’s going to really drive the longevity of this market,” he said. “Everyone asks, when do you stop taking these? What does that look like? We don’t have a good answer.”
Tea Leaves Expected at ADA
While Lilly and Novo have been head-to-head for years, there are more oral candidates on the horizon. Pfizer’s Metsera-acquired PF’3944 passed muster earlier this month with data that will send the asset into two Phase III studies. Analysts clamored for more detailed information on the company’s fourth quarter and full year earnings call but ultimately will have to wait until June when more details from the VESPER-3 study are revealed at the American Diabetes Association (ADA) conference.
Also presenting data at ADA is Structure Therapeutics, which announced in December what BMO called “highly competitive” topline Phase II data for its oral GLP-1 candidate, aleniglipron. In addition to more detailed data on this asset, Risinger noted that Structure may also present results from a Phase I trial of ACCG-2671, its dual amylin and calcitonin receptor agonist.
“There is probably a limit as to what you can do with a small molecule, which is why Structure is looking at amylin,” Seigerman said.
With new data pouring in from Roche, Pfizer and other challengers to Novo and Lilly’s reign over the obesity space, and constant M&A rumors surrounding Viking Therapeutics and others, 2026 is shaping up to be an eventful year.
Editor’s note: Heather McKenzie contributed reporting to this story.
