Amgen aims to enter the weight-loss drug market with a new approach

Amgen International is taking a new approach in its quest to stand out in a crowded field of drugmakers racing to develop the next blockbuster weight loss drug.

The biotech company is testing an injectable treatment that helps people lose weight differently than existing injections Novo Nordisk And Eli Lilly, and other obesity drugs are under development. Amgen's treatment, called MariTide, appears to help patients maintain weight after they stop taking it.

The drug company is also testing the drug to be taken once a month or even less frequently, which may provide greater relief than weekly medications on the market.

It's too early to say how competitive Amgen will be in the emerging weight-loss drug space, which has been dominated so far by Novo Nordisk and Eli Lilly.

Some analysts expect the market to be worth $100 billion by the end of the decade, which could leave room for new competitors to enter. Goldman Sachs also predicts that between 10 million and 70 million Americans will be taking weight-loss medications by 2028.

The available data on Amgen's injectable drug is promising, but is from a small, early-stage clinical trial. The company, based in Thousand Oaks, California, is developing an oral drug and other treatments for obesity, but has revealed few details about them.

Investors and health experts will likely get a better idea of ​​Amgen's prospects later this year: The drug company expects to release preliminary data from its ongoing mid-stage trial of MariTide, along with Phase 1 data on its obesity pill.

It's also unclear whether Amgen's treatments will be cheaper than current weight-loss drugs, which cost about $1,000 a month.

Novo Nordisk's Wegovy and Eli Lilly's Zepbound lead a new category of obesity treatments that have attracted relentless patient demand — and investor interest — despite their steep prices and limited insurance coverage.

Eli Lilly and Novo Nordisk have also struggled to provide adequate supplies of their treatments, which could give other companies a chance to gain market share.

Amgen offers a new twist in weight loss.

As with Wegovy and Zepbound, part of Amgen's treatment activates a gut hormone receptor called GLP-1 to help regulate a person's appetite.

But while Zepbound activates a second hormone receptor called GIP, Amgen's drug blocks it. Wegovy does not target GIP, which suppresses appetite like GLP-1 but may also improve how the body breaks down sugar and fat.

Amgen's decision to reduce rather than boost GIP activity is based on genetics research that suggests blocking the receptor is associated with decreased fat mass and body weight, company executives said.

This seems to go against how Zepbound works. Eli Lilly's approach has proven successful: The treatment helped obese patients lose up to 22.5% of their weight after 72 weeks in a late-stage trial.

But Amgen's MartiTide was also effective in a small, early-stage study.

Patients who got the highest dose of Amgen — 420 milligrams — each month lost an average of 14.5% of their body weight in just 12 weeks, according to data from a phase 1 trial published last month in the journal Nature Metabolism.

There is a broader debate among researchers about why both approaches – blocking and activating GIP – are effective in promoting weight loss.

One theory is that repeated activation of the GIP receptor, as Zepbound does, eventually causes the body to “self-regulate” and make sure there isn't too much GIP activity, says Dr. Carolyn Apovian, director of the Weight Center. Administration and Wellness at Brigham and Women's Hospital.

This reduces overall GIP activity, which is thought to essentially mimic what the Amgen drug achieves when it blocks the GIP receptor. But Apovian cautioned that “none of this has been proven” and that more data is needed.

Preliminary trial data suggests Amgen's treatment may be better at helping people maintain weight loss than competitors, even though patients take it less frequently.

The Amgen study included 110 patients with obesity but not diabetes. Patients in one group were randomly assigned to receive a single dose of the drug and were followed for 150 days, while the second group was given a dose every four weeks for three months.

Patients who received a single dose of the highest dose of MariTide lost up to 8.2% of their body weight after 92 days. This suggests that a single injection of the drug has a long-term effect on weight loss, according to the study authors.

In the group that received multiple doses of the drug, patients appeared to maintain maximum weight loss until about two months after the last dose. Body weight slowly began to return after that. However, their weight decreased by 11.2% five months after receiving the last dose.

“We think the meaningful weight loss is actually 5%,” said Dr. Holly Lofton, director of Weight Loss. “If you take Amgen, lose 14.5%, stop taking the medication, and continue to lose 11.2% after a few months, that's significant.” Management Program at NYU Langone Health and Obesity Medicine Physician. But she pointed out the need to study the treatment on a larger group of people.

The sustained weight loss in the Amgen study appears to be in contrast to the results seen in the clinical trials of Zepbound and Wegovy. Patients in these studies noticed that their weight regained faster after stopping the injections.

Amgen's drug frequency also sets it apart. Wegovy or Zepbound users must take weekly doses, compared to MariTide which is taken once a month.

Amgen's trial used monthly dosing in part because patients saw sustained weight loss whether they got a single injection or multiple doses of the company's drug, according to the study authors.

Amgen's treatment can also remain in the body much longer than current treatments such as Wegovy and Zepbound because it includes a monoclonal antibody, the researchers added.

Amgen's MariTide has this advantage in that it will last much longer. Even if you give a high dose, your body will still be exposed to the drug for a month or two, so this clearly shows that you don't. “You don't need to take it every week,” Matt Phipps, a William Blair & Company analyst, told CNBC.

People typically don't want to get injections that often, so some patients may prefer a monthly injection like Amgen's MariTide for a disease that will likely require chronic treatment, Phipps said.

But he noted that patient choice may also depend on whether the level of weight loss and side effects of Amgen's drug are on par with those of current weekly injections.

Amgen's ongoing phase 2 trial is exploring whether patients can take the drug less frequently than once a month.

Amgen's long-term Phase 2 study in nearly 600 patients will provide more clarity on how MariTide competes against Wegovy and Zepbound. The company is exploring which dosage strength and schedule is best for patients. It expects to publish preliminary trial results later this year.

Some analysts said the phase 2 trial could help address several questions, including how well patients can tolerate treatment at different dosing regimens.

The 52-week study is testing 11 different patient groups in a variety of dose levels and treatment regimens. This involves starting with a lower dose of the medication for some patients and gradually increasing it until they reach a higher target dose.

Dose escalation could help reduce the side effects some patients experienced after taking the first dose of MariTide in the phase 1 trial, according to Phipps.

In that trial, Amgen's safety and side effects were similar to other GLP-1 drugs. Nausea and vomiting were the most common side effects, usually lasting for approximately 72 hours.

According to the study, four out of eight patients in the group that received the highest dose of the treatment withdrew before getting a second dose after reporting mild gastrointestinal problems. But no other patients stopped taking the drug due to adverse events across any of the different dose groups, Paul Burton, Amgen's chief medical officer, said during a conference earlier this month.

“It's a bit too early to jump to the conclusion that patients won't tolerate the drug based on the phase 1 data,” William Blair & Co.'s Phipps said.

Another part of Amgen's Phase 2 trial will also examine weight loss after 52 weeks, which will provide a clearer picture of how long the drug is effective.