Hi Luis Carlos Agripino de Carvalho Jr.,
Yes you need an AnyConnect Apex license:
http://www.cisco.com/c/en/us/support/docs/security/asa-5500-x-series-firewalls/200353-ASA-Multi-Context-Mode-Remote-Access-A.html
Licensing
- AnyConnect Apex license required
- Essentials licenses ignored/not allowed
- Configurability to control maximum license usage per context
- Configurability to allow license bursting per context
Hope this info helps!!
Rate if helps you!!
-JP-