(Adds details on AstraZeneca deal, and updates trial data for Novo, Amgen, Viking Therapeutics and Zealand Pharma)

Dec 4 (Reuters) - The race to grab a slice of the lucrative market for obesity treatments is heating up among drugmakers, with Swiss company Roche becoming one of the latest entrants following its $2.7 billion deal to buy Carmot Therapeutics.

The market for obesity treatments is estimated to be worth $100 billion by the end of the decade and already has Novo Nordisk and Eli Lilly making a big splash with their highly sought-after treatments.

The following is a list of companies targeting the next big blockbuster opportunity:

NOVO NORDISK

Novo Nordisk, in November, shared additional data from a late-stage study showing the heart protective benefits of Wegovy, its popular obesity drug, are not solely due to weight loss.

The study showed the difference in heart risk between patients who received Wegovy, known chemically as semaglutide, and those on placebo began to appear almost immediately after starting treatment.

Novo has submitted applications to the U.S. and European Union health regulators for expanded use of Wegovy to reduce the risk of cardiovascular events.

The company's weekly injection Wegovy, known as Ozempic when used for diabetes, has been launched in six countries so far including the United States.

ELI LILLY

Eli Lilly's weight-loss therapy, Zepbound, got the green light from the U.S. and UK regulators recently, paving the way for a powerful new rival to Novo's Wegovy.

Lilly's drug, chemically known as tirzepatide, has been available as Mounjaro for type 2 diabetes since 2022.

Lilly said a mid-stage trial of its next-generation obesity drug candidate, a once-weekly injection of retatrutide, showed it led to a weight loss of up to 24.2% after 48 weeks.

PFIZER

Pfizer said on Friday it was stopping further trials of a twice-daily version of its oral weight-loss drug, danuglipron.

The decision comes after most patients in a mid-stage trial dropped out with high rates of side effects such as nausea and vomiting.

The company said it will instead focus on a once-daily, modified release version of danuglipron. Data on how this version interacts with the human body is expected next year.

Pfizer had earlier scrapped the development of its once-a-day pill in June due to concerns over liver safety.

ROCHE AND CARMOT THERAPEUTICS

Roche acquired CT-388 as part of its $2.7 billion buyout of Carmot Therapeutics. Carmot's once-a-week injection belongs to the same class as Eli Lilly's Mounjaro, or Zepbound.

The newly acquired drug candidate has completed early-stage trials and is ready to be tested on humans in the second of three trial stages, Roche said.

ASTRAZENECA

AstraZeneca licensed an experimental weight-loss pill for up to $2 billion from China's Eccogene that it believes could cause fewer side effects than current injectable treatments.

Eccogene's drug candidate, ECC5004, is only in the first of three stages of clinical trials.

AMGEN

Amgen said in October it expects to report findings from an early-stage trial of experimental obesity pill, AMG786, in the first half of next year, and results from a mid-stage trial of a different, injected obesity candidate AMG133, by late next year.

AMG133 has shown a mean weight loss of 14.5% after 12 weeks of treatment at the highest monthly dose in a small study.

ALTIMMUNE

Altimmune said its drug candidate, pemvidutide, helped reduce weight by 15.6% on average and showed continued weight loss at the end of treatment in a mid-stage trial.

However, patients also experienced nausea and vomiting of mild and moderate severity.

VIKING THERAPEUTICS

Viking Therapeutics' drug, VK2735, showed up to 6% reduction in mean weight in an early-stage study.

The company said in October it plans to report data from a mid-stage study testing higher doses of the drug over a longer treatment window in the first half of 2024.

ZEALAND PHARMA AND BOEHRINGER INGELHEIM

Germany's Boehringer Ingelheim in August said it would conduct three late-stage studies testing experimental obesity treatment, survodutide, which it co-invented with Danish biotech Zealand Pharma.

The drug candidate has shown to reduce body weight by close to 19% in a mid-stage trial in participants who had reached the intended dosage level.

OPKO HEALTH

Opko Health has completed a mid-stage trial of its obesity drug candidate which it expects will have fewer side effects compared to existing treatments. (Reporting by Mariam Sunny, Pratik Jain, Sriparna Roy and Bhanvi Satija in Bengaluru; Editing by Sriraj Kalluvila, Anil D'Silva and Shinjini Ganguli)