You may learn more about the API functionality in the VirusTotal Developer Hub.
Should you need to perform advanced searches, bulk file or URL submissions or simply need a higher request throughput or daily allowance, there is a premium VirusTotal API that may suit your needs. The premium API returns much more information about samples, URLs, domains and other items handled by VirusTotal. It also allows you to download malware for further scrutiny. Other features include reverse lookups that take you from characteristics (detection rates, file types, binary content, behavioural patterns, etc.) to lists of samples matching your search criteria, as well as programmatic interaction with VT Hunting and VT Intelligence features.