If Q7A does not apply to API starting materials, is it necessary or mandatory to, first of all, audit manufacturers of API starting materials? And B, if an API manufacturer decides to audit the manufacturers starting materials, against which document should the audit be conducted?

There is no expectation in Q7A to audit a manufacturer of an API starting material because Q7A is very clear and states that the document does not apply to the manufacture of an API starting material. In general, API starting materials are subject to the sections of Q7A regarding qualification of a raw material vendor, and an API starting material supplier should be qualified like any other raw material supplier. The language in Q7A does not specifically talk about and does not mention auditing as a function. It talks about verifying the laboratory test results from your vendor by doing your own testing in house and comparing your laboratory test results against the test results received on a Certificate of Analysis. That doesn’t prohibit you from auditing an API starting material manufacturer if you feel that there is a need, in your particular situation.