Redirect traffic from a virtual service to a knative service

I am trying it like this but I cannot get it to work, I get 404.

apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: app-api-virtual-service
spec:
  hosts:
    - api.mydomain.io
  gateways:
    - app-ingress-gateway
  http:
    - route:
        - destination:
            host: app-api-serverless

If I replace destination with a specific knative revision on its private service, it works, like:

        - destination:
            host: app-api-serverless-00013-private