Amazon API Gateway simplifies accessing private APIs by allowing you to associate one or more Amazon Virtual Private Cloud (VPC) Endpoints to a private API. API Gateway will create and manage Route53 alias records necessary for easily invoking the Private APIs. With this feature, you can leverage Private APIs in web applications hosted within your VPCs.  

from Recent Announcements https://aws.amazon.com/about-aws/whats-new/2019/09/amazon-api-gateway-simplifies-invoking-private-apis/