Yes. Secure email configuration which allows email communication during the submission process has been completed and the FDA considers these email domains secure:
Use of secure email allows communication between FDA and sponsors. It is not a substitute for formal submissions. Formal submissions (e.g., new INDs and amendments) must be submitted to the respective center’s document room (paper submissions) or via the electronic gateway, as applicable.
For more information see FDA Guidance: Best Practices for Communication Between IND Sponsors and FDA During Drug Development