(Can't comment much on 2015 and its python integration as we're still on 2013, but here's a legacy solution: )
If the script is strictly external and doesn't interact with 3ds max, you could get away with DOScommand() and HiddenDOScommand(). You could format the arguments to strings, pass them in the command string, then parse them from sys.argv on the script side.
DOScommand ("python \"C:\\path\ o\\your\\script.py\" " + arg1 as string + " " + arg2 as string + " " + and_so_on as string)
HiddenDOScommand() works similar, it's what you'd use if you want the CMD window not to show.
There's only so much that can do, though. The command length is limited by windows and dealing with CMD quirks rarely means happy times.
If all else fails, there's always writing and reading a temp file...