The positive results from the SURMOUNT-OSA phase 3 trials of tirzepatide in treating obstructive sleep apnea, along with the significant body weight reduction observed, are likely to enhance investor confidence in Eli Lilly. The announcement of plans to submit these findings to the FDA and other global regulatory bodies further supports the potential for tirzepatide's approval for this new indication, which could expand its market significantly. The immediate positive reaction in premarket trading indicates strong investor optimism about the drug's future prospects.