http://www.cgmp.com/fda483.htm This is the form used by investigators to record their observations of non-compliance with cGMPs. While firms are not required to respond to 483's, it is considered prudent to do so, telling the FDA what will be done to correct not just the immediate, specific problem, but also the system(s) that are the root(s) of the problem.
BTW, I do not know of any occurrence of a company successfully not responding to a 483.