On November 17, Novo Nordisk announced that its weight loss version of semaglutide (brand name "NovoYing") has officially launched in the Chinese market, which has more than 180 million people with obesity, ahead of Eli Lilly. In June, semaglutide received approval from the Chinese National Medical Products Administration (NMPA), and in July, Eli Lilly’s tirzepatide was also approved for weight loss, but it has not yet been launched in China.
As of now, whether in the diabetes or weight loss market, Novo Nordisk holds the top position. There's a saying in the pharmaceutical industry: “Being the first to market is good, but if you can’t be first, you should strive to be the best.” Following this advice, as the indications for GLP-1 drugs increase and the market expands, research on GLP-1 drug candidates has focused on addressing two major flaws in existing drugs:
Figure 1 GLP-1 drugs continue to grow
Novo Nordisk’s drugs Ozempic (for type 2 diabetes) and Wegovy (for obesity), along with Eli Lilly’s new drug Zepbound (for obesity), have seen impressive sales growth. JPMorgan estimates that by 2030, the GLP-1 drug market will exceed $100 billion. It is estimated that 9% of the U.S. population may eventually use these drugs, which represents a huge market. Currently, Novo Nordisk holds 65% of the global GLP-1 market share, Eli Lilly holds 32%, and the remaining companies only account for 3% of the market share.
Figure 2 Number of patients with diabetes and obesity using GLP-1 drugs worldwide
From 2019 to 2023, the diabetes market grew by 12%, with GLP-1-based injectable therapies increasing by 26%, driven by Ozempic. However, insulin has seen negative growth in the market, indicating that GLP-1 treatments are gaining market share at the expense of insulin. If governments lower insulin prices, this growth might not be sustainable.
Figure 3 Global diabetes market by therapeutic category
The global obesity treatment market continues to grow at an astronomical rate, with a 114% growth rate as of August 2024, reaching DKK 118.3 billion (approximately $16.63 billion). Due to Eli Lilly's strong market entry, Novo Nordisk has begun to lose some market share but still controls 73% of the market.
Figure 4 Global obesity market size and growth rate
Eli Lilly’s rapid market share acquisition and its emergence as a major competitor to Ozempic and Wegovy is due to one simple and obvious reason: Eli Lilly’s tirzepatide is superior to Novo Nordisk’s semaglutide.
A study published in the New England Journal of Medicine showed that tirzepatide reduced HbA1c (glycated hemoglobin) by 2% to 2.5%, while semaglutide only reduced it by 1% to 2%.
Figure 5 Changes in HbA1C
The study also indicated that tirzepatide resulted in weight loss ranging from 7 kg to 13 kg, while semaglutide’s weight loss range was 6 kg to 10 kg.
Figure 6 Changes in body weight
Currently, the leaders in the weight loss field—Eli Lilly and Novo Nordisk—are competing to develop pill-based obesity treatments, with Pfizer and AstraZeneca also entering the market. The competition in the oral GLP-1 drug space is intense, but Viking Therapeutics' oral VK2735 is leading the way.
This month, Viking reported phase 1 trial data for its oral VK2735, a dual GLP-1/GIP receptor agonist, similar to Eli Lilly’s blockbuster weight loss drug Zepbound, designed to treat obesity and other metabolic disorders. The results were built upon positive data from doses up to 40 mg, showing strong weight loss effects and good safety and tolerability.
Additional data presented at ObesityWeek showed that higher doses also resulted in good weight loss, with the 100 mg dose yielding the best results—8.2% absolute weight loss after just 4 weeks of treatment, compared to 6.8% weight loss in the placebo group.
Table 1 Body weight changes after 28 days of oral administration of VK2735
We noted that there were no significant differences between the 40 mg, 60 mg, and 80 mg doses, with similar weight loss and absolute changes of -5.1%, -4.1%, and -5.2%, respectively. The percentage of patients with ≥5% weight loss was 57%, 38%, and 63% for the 40 mg, 60 mg, and 80 mg doses. The 100 mg dose showed markedly better weight loss, and importantly, these results were not driven by outliers, as every patient experienced at least a 5% weight reduction.
Table 2 shows that VK2735 had good safety and tolerability at higher doses, with most adverse events (90%) being mild or moderate. 84% of gastrointestinal side effects were mild, with the remainder being moderate. Compared to other oral obesity drug trials, reports of nausea, vomiting, diarrhea, and constipation were significantly lower, far below the rates seen in Roche’s oral GLP-1 candidate, CT-996.
Table 2 Common gastrointestinal adverse events after 28 days of oral administration of VK2735
Roche briefly led the oral GLP-1 drug space earlier this year, but when detailed data was submitted showing poor tolerability, Roche’s advantage disappeared. Therefore, combining good weight loss results with acceptable safety and tolerability is key for oral weight loss drugs, and Viking’s VK2735 delivers on both.
Viking plans to launch phase 2 studies of oral VK2735 for obesity by the end of 2024. This oral formulation is being developed as an alternative for patients who are hesitant about injectable therapies and want to maintain their weight loss results.
Zepbound, Ozempic, and Wegovy are all injected weekly using a dedicated device, but due to a shortage of medical device injectors, Eli Lilly announced that it would distribute Zepbound in vials, with patients needing to self-inject. The shortage of current GLP-1 drugs is due to limited supply of injectors, not the drugs themselves. This trend indicates a growing demand for longer-acting GLP-1 drugs.
Amgen has abandoned the development of an early obesity pill and is focusing on the development of a more durable injectable GLP-1 receptor agonist, AMG133, also known as MariTide. This candidate drug is considered a potential competitor to Novo Nordisk’s Wegovy and Eli Lilly’s Zepbound.
According to Amgen’s phase 1 trial data, MariTide shows excellent pharmacokinetic properties, helping to differentiate it from competitors.
At various dose levels, MariTide has a long retention time in the blood, with a half-life of 14 to 15 days, allowing the therapeutic levels to last up to 4 weeks after a single injection.
Figure 7 MariTide PK data
Based on these results, MariTide can be administered once every 4 weeks, with dose-dependent weight loss observed compared to the placebo.
Figure 8 MariTide efficacy data
On the 26th, Amgen announced positive results from a 52-week phase 2 trial of MariTide for treating type 2 diabetes and obesity.
MariTide’s weight loss advantage was not significant. In obese or overweight individuals without type 2 diabetes, MariTide led to an average 20% weight loss after 52 weeks , while tirzepatide’s phase 3 trial showed a 21-22% weight loss after 72 weeks of treatment. Therefore, MariTide’s weight loss was below market expectations. 
Figure 9 Weight loss effect of MariTide treatment for 52 weeks in obese or overweight patients without T2D
In obese or overweight individuals with type 2 diabetes, MariTide led to an average weight loss of 17% after 52 weeks. No weight loss plateau was observed in either group.
Figure 10 Weight loss effect of MariTide treatment for 52 weeks in obese or overweight patients with T2D
HbA1c dropped by up to 2.2% at week 52, similar to the results from CagriSema (a combination of semaglutide and cagrilintide developed by Novo Nordisk) in its phase 2 trial. In addition, MariTide improved blood sugar control, reduced systolic blood pressure, triglycerides, and hs-CRP.
Figure 11 Results of cardiometabolic disease markers in obese or overweight patients with T2D treated with MariTide for 52 weeks
Based on phase 2 data, MariTide is expected to show a weight loss increase from 20% at 52 weeks to 22-23% after 68 or 72 weeks of treatment in phase 3 trials. In contrast, CagriSema and retatrutide (a triple receptor agonist developed by Eli Lilly) are expected to show weight loss results in the range of 24-27% based on available phase 2 data.
Although MariTide may not be competitive with the next-generation therapies from Novo Nordisk and Eli Lilly, the commercial potential of a monthly dosing formulation remains promising. Unlike weekly subcutaneous injections of tirzepatide, semaglutide, CagriSema, or retatrutide, MariTide offers the convenience of monthly dosing, which could be a significant advantage. MariTide is the first weight loss therapy to show safe and effective weight loss with a monthly or longer dosing interval in phase 2 trials.
Given the severe shortage of GLP-1 drugs due to huge demand, Amgen’s long-acting injectable drug, if approved, should capture a significant market share.
GLP-1 weight loss drugs are undoubtedly a long-term growth story, with pharmaceutical companies racing to find the next breakthrough. In the coming months, data from several new GLP-1 drugs will be released. With a fast-paced “you take your turn, I take mine” situation, the speed of updates for best-in-class GLP-1 drugs has never been faster.
When I first began drafting this article, Amgen’s MariTide phase 2 data had not been released yet, and based on phase 1 data, expectations were high. Now, with phase 2 clinical results showing positive but not significantly superior efficacy, MariTide’s position as a best-in-class candidate is precarious. However, the commercial prospects of its monthly dosing formulation remain broad. Attention can now turn to Viking’s phase 2 clinical results for oral VK2735.
https://www.novonordisk.com/content/nncorp/global/en/news-and-media
https://www.statnews.com/2024/05/02/amgen-maritide-obesity-injectable/
https://seekingalpha.com/news/4303757-novo-nordisk-reportedly-launches-wegovy-in-china
https://vikingtherapeutics.com/
https://www.nejm.org/doi/full/10.1056/NEJMoa2107519#ap0%20
https://investors.amgen.com/static-files/0176d78e-920b-45b3-b9cc-a727e58e80da
