To be even more pedantic, it's "Sic transit gloria + genitive case". If we use Leica, ae (I declination) than it must be Sic transit gloria Leicae (genitive singular).
I defer to the native speaker of modern Latin, i.e. Italian, and his knowledge of ancient Latin, far superior to my 40-year-old hazy memory of high school Latin.
I was in my bank a couple of months ago at lunchtime at the counter getting some cash, when a guys wife came in and caught him with his girl friend, there was a terrible fight that the police had to be called to break it up, and they arrested them all.