使用wordpress重写规则时忽略特定页面

I'm wondering how I can tell wordpress rewrites to IGNORE a specific page, such as: index.php?p=15 I've tried several things, like:

RewriteCond %{REQUEST_FILENAME}!^/index.php?p=15 !-d

Or trying to specify the rule before the wordpress rules etc, but nothing has worked out so far.

Any ideas on how I can make this work?

I've tried the following code, and it seems to work properly :

RewriteCond %{REQUEST_URI}:::%{QUERY_STRING} !test\.php:::p=15$
RewriteRule . /index.php [L]

Everything is redirect to /index.php except for test.php?p=15.