** Shares of AIM Vaccine Co Ltd 6660.HK jump as much as 13.2% to HK$6.35; on course for biggest one-day gain since October 17, 2024

** Stock on track for the second session of gain

** AIM says U.S. Food and Drug Administration (FDA) has approved its application for clinical trial of mRNA respiratory syncytial virus vaccines

** The Chinese mRNA vaccine products developer says it is U.S. FDA's first approval for the company's products, marking a "significant progress" for its global strategy

** Hang Seng Commerce & Industry Index .HSNC and Hang Seng Index .HSI both add 0.1%, healthcare index .HSCIH gains 0.2%

** Stock up 1.5% YTD

(Reporting by Donny Kwok)

((donny.kwok@thomsonreuters.com))