It its cGMP regulations for medical devices (21 CFR 820 (Quality System Regulations), the FDA also addresses the topic of validation (21 CFR 820.75). It states that "where the results of a process cannot be fully verified by subsequent inspection and test, the process shall be validated [...]". This should be documented according to the respective procedures established.
In the course of its inspections, the FDA reviews the validation of the manufacturing processes. That's why the FDA criticised a Taiwanese manufacturer of medical devices in a Warning Letter last autumn for not having any validation documents (validation plans and reports). Besides, a storage period hadn't been validated at that company. Interestingly, the FDA required a random statistical sample for the validation of the storage period.
The company responded to those deficiencies but not to the extent expected by the FDA, though. Among other things, the FDA criticised that only extracts of the validation plan were sent and that neither a document number, nor the date of the coming into force, nor signatures were included. Again, the missing rationales for a sampling plan were criticised. Finally, the FDA required an assessment (review) of all processes not completely verified and the justification for their validation. Furthermore, the FDA required CAPA measures with regard to those reviews.
Please also see the complete FDA Warning Letter to BroadMaster Biotech Corp.