On October 7, 2013 version 7.5 of ITMS was made generally available. Symantec Corporation will End of Life (“EOL”) the earlier releases of this product including Components, Agents, Options any Maintenance Packs (MPs) and/or patches for each version, in all released languages.
The official source of information for end of life dates is here:
Choose the product and then the 'release details' link on the right hand side. Then select the required version.