A number of clinical trial data provided a peek into the stiff competition developing in the obesity treatment space as three drug giants battle for a piece of what is estimated to be a $100 billion market by the end of the decade.

Novo Nordisk (NVO), the market leader, currently has two drugs on the market approved for Type 2 diabetes (Ozempic) and obesity (Wegovy) — both of which are injectables. It also has Rybelsus, its pill for Type 2 diabetes, which the company is also studying for treating obesity.

Results from a Phase 3 trial show the pill, at a higher dosage, was effective in reducing weight by 15% for participants.

Novo Nordisk's greatest competition remains Eli Lilly (LLY). The two are already fierce competitors in the diabetes care and insulin space, and Eli Lilly has a number of competing products on the market and in the pipeline.

Eli Lilly announced Phase 2 data last week for its oral candidate, orforglipron, showing up to 14.7% weight loss. On Monday, it revealed Phase 2 data for its experimental weight loss injection, retatrutide, showing up to 24% weight loss.

The latter is a different subclass of drugs but shows better data than the company's current Type 2 diabetes injectable, Mounjaro. Eli Lilly is also pursuing FDA approval for Mounjaro as a weight loss option for those without diabetes.

Pfizer (PFE), meanwhile, is finding its footing in the oral treatment race. Pfizer said it would pursue its twice-daily pill, danuglipron, over its once-daily candidate, lotiglipron, due to concerns of elevated liver damage risk in early-stage trials. The company is moving the drug into Phase 2 to figure out the most effective dosing but said it will also work on trying to make it a once-daily pill in order to compete with Rybelsus and orforglipron. In that regard, Pfizer is a laggard.

Meanwhile, insurance coverage remains a hurdle to access. Due to concerns that patients may have to stay on the drugs forever to keep the weight off, insurers are wary of covering them. And though a new study showed half of US adults would be willing to pay $100 per month for a weight loss drug, the cost of Wegovy and Ozempic ranges from more than $800 to more than $1,300 out of pocket.

Follow Anjalee on Twitter @AnjKhem

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