If U are thinking of Running the QTP Script without opening QTP than it can be done directly by VBScript alone.
Make a base driver which will be opening the QTP Application also call and execute your testcases drivers.
It must be a .net app because of other business rules.
We can do this creating a COM object of QTP right?
But I have to know wich files we need in the client machine to run the script. Every developer and tester will run thoses tests here.