A trademark application filed on an intent-to-use basis confers no right of enforcement prior to actual use of the trademark with the goods covered by the application. That is, without actual commercial use of the trademark in U.S. commerce, an applicant of an intent-to-use trademark application has an unenforceable trademark and should not claim trademark infringement. Use in commerce occurs when branded goods are transported or sold across state or federal borders and is a requirement to achieve federal trademark registration in the U.S.
If you have received a letter alleging trademark infringement, it is important to look closely at the rights being asserted. Some trademarks even though registered are unenforceable trademarks.