Lilly and Novo are the kings of weight-loss drugs. The companies coming for their crowns.

While Lilly and Novo are still the only two companies with approved weight-loss drugs on sale in the U.S., others are coming for a share of the growing sector.

Any way you slice it, the market for weight-loss drugs like the so-called GLP-1 medication made by Lilly and Novo is likely to be huge. Morningstar is one of the most optimistic on this potential, seeing a $200 billion market by 2031.

Goldman Sachs cut its estimate in April to $95 billion by 2030, down from $130 billion. That is arguably still a very large number and has attracted more companies to the lucrative industry.

Both well-established pharma companies as well as smaller, clinical-stage firms are investing heavily to be able to someday compete with Lilly and Novo.

Here’s a look at some of the contenders:

Amgen

As one of the largest pharmaceutical companies in the U.S., Amgen has pockets deep enough to invest in the booming obesity drug space, and its drug MariTide has shown potential. Its distinct advantage over current jabs is that it would only have to be injected once a month, as opposed to once a week like Lilly’s Zepbound and Novo’s Wegovy.

In a mid-stage trial, patients lost on average about 20% of their body weight after a year on MariTide, roughly on par with rivals, but a surprisingly large number of participants dropped out due to side effects. A late-stage trial is ongoing.

Viking Therapeutics

Small cap Viking Therapeutics is a clinical-stage biotech and doesn’t yet generate revenue. It announced as late as June 25 that it started a late-stage trial of its injectable weight-loss treatment VK2735.

VK2735 is a so-called dual GLP-1 and GIP receptor, meaning it targets two different gut hormones to help control blood sugar levels and appetite, thereby helping patients lose unwanted weight.

It’s also conducting a mid-stage trial for VK2735 in pill form. An early-stage trial showed adults on the highest dosage of the drug lost on average 8.2% of their body weight in four weeks.

Zealand Pharma

This Danish up-and-comer has partnered with Roche and privately held Boehringer Ingelheim to develop next-generation weight-loss drugs.

Zealand’s portfolio includes medicines targeting both GLPs and GIPs receptors (Dapiglutide/Survodutide/ZP6590) as well as a so-called amylin analog (Petrelintide), which works differently from GLP-1s to increase feelings of fullness. There are hopes that amylin could produce fewer side effects than GLP-1 drugs.

Structure Therapeutics

Structure Therapeutics is a San Francisco-based clinical-stage biotech that is also developing an amylin receptor agonist, ACCG-2671. It expects to start an early-stage trial of the drug by the end of 2025. Preclinical trials have shown significant weight-loss, but also less severe side effects and muscle mass preservation, according to Structure executives.

The company also has an oral GLP-1 candidate in the pipeline.

AstraZeneca

The U.K.’s most valuable company by market capitalization AstraZeneca is another Big Pharma player wanting to get into weight-loss drugs with its candidate AZD5004.

The treatment is a small molecule oral GLP-1. Type 2 diabetes patients lost 5.8% of their body weight loss after four weeks of taking the daily pill, with mild to modest gastrointestinal side effects. The drug was licensed by AstraZeneca in 2023 from China’s Eccogene and is currently in a mid-stage trial.

It has two other injectable weight-loss drugs in the pipeline as well.

Roche Holdings

Swiss-listed Roche is developing three different weight-loss drugs, one in partnership with Zealand Pharma.

Its portfolio includes both oral and injectable weight-loss medicines, and both single and dual receptor antagonists. Hopes are high, especially for its oral version, but there have been concerns about side effects.

Its jab is in a mid-stage trial while its pill is in an early-stage trial.

Write to Elsa Ohlen at elsa.ohlen@barrons.com