Next is a new spin-off, which will focus on Josuke and Hol Horse and is written by Kouhei Kadono (Boogiepop and Others) with art by Tasuku Karasuma (No Guns Life). This is the first JoJo manga spin-off where Araki is not involved with the story or art. The spin-off will start this winter.
[Source: Manga Mogura RE (link 2), JoJo Wiki]