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Shares of Eli Lilly & Co. LLY slid 4.73% to $869.58 Friday, on what proved to be an all-around positive trading session for the stock market, with the S&P 500 Index SPX rising 0.55% to 5,770.20 and the Dow Jones Industrial Average DJIA rising 0.52% to 42,801.72.

Eli Lilly and Company’s LLY shares dipped almost 5% on Monday after rival Novo Nordisk NVO announced disappointing data from a late-stage study on next-generation obesity drug, CagriSema. Top-line data from the phase III REDEFINE 2 study on Novo Nordisk’s CagriSema showed that treatment with the drug led to a weight loss of 15.

Eli Lilly (NYSE: LLY) stock has had plenty of good trading sessions over the past year or so, but Monday's sure wasn't among them. The storied pharmaceutical company's shares lost nearly 5% of their value during the big market sell-off that day,