Not exactly on topic but whatever happened with J&J? Disappeared and I never hear anything pro or con.
I also wonder. I had the J&J vax in Apr 2020. My sister was immune compromised and panicked, so I waited for JJ. All I know about it is that it was not gene therapy. Guess it had to be killed.
To answer your question on the J&J...
https://www.hematology.org/covid-19/vaccine-induced-immune-thrombotic-thrombocytopenia