Definitely not necessary and probably discouraged unless we have anything substantial to say. Their FAQ says they’ll take pubs, awards, etc.
Grading: For the upcoming admissions cycle (2026) we will accept courses on a Pass/Fail, Pass/No Pass, and Satisfactory/Unsatisfactory basis. In addition, Duke will also accept online courses. We prefer, however, that science and laboratory classes are conducted in person and for a letter grade.
medschool.duke.edu
Unclear if it matters a week after your interview anyways tho since your portal will close to updates. I’ve also heard mixed things about sending intent letters because so many students back out later and they don’t explicitly say they take them but I’m not an expert there.