(Bloomberg) -- The Eli Lilly & Co. executive who oversaw development of Mounjaro, its blockbuster diabetes medicine that’s also used for weight loss, will retire at the end of the year.

Mike Mason will step down as executive vice president of diabetes and obesity, the company said Wednesday in a statement, and will be replaced by Patrik Jonsson, who will also continue in his role as president of Lilly USA. 

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Long a leader in diabetes, Lilly has seen GLP-1 diabetes medications that also help patients lose weight become a huge driver of growth. Now approved only for diabetes treatment, Mounjaro is under review for clearance in weight loss, and doctors already prescribe it for that purpose. Lilly is developing more obesity therapies, including a shot that led to patients shedding as much as 24% of their body weight in a study that lasted just less than a year. 

Daniel Skovronsky will relinquish his role as chief medical officer to David Hyman, who will continue to oversee oncology business development. Skovronsky will remain chief scientific officer and take on Jonsson’s duties as president of immunology, which includes marketed and experimental drugs for dermatology, gastroenterology and rheumatology.

“The deep experience of our leadership team ensures that we will continue to accelerate our efforts in effective, innovative ways,” Chief Executive Officer David Ricks said in the statement. 

The shares rose 1% at 9:45 a.m. in New York trading. The stock has gained 44% this year through Tuesday’s close. 

(Updates with opening shares in final paragraph)

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