BURLINGTON, Mass. — Eli Lilly’s and Amylin Pharmaceuticals’ Type 2 diabetes drug, Bydureon, appears to work better at promoting weight loss than drugs made by Takeda and Merck, but it could face a challenger of its own.

Market research firm Decision Resources found that while Lilly’s and Amylin’s Bydureon (exenatide) was better able to promote weight loss among patients than Takeda’s Actos (pioglitazone hydrochloride) and Merck’s Januvia (sitagliptin), Bristol-Myers Squibb’s and AstraZeneca’s investigative drug dapagliflozin could challenge Bydureon in this aspect as well.

Decision Resources said the Type 2 diabetes market would experience strong growth over the next decade, increasing from $20.5 billion in 2009 to $36 billion in 2019 in the United States, United Kingdom, France, Germany, Italy, Spain and Japan.