The film Van Helsing was released in May of 2004. The hero, Gabriel Van Helsing, is not the same character as Bram Stoker's 1897 Dracula character Abraham Van Helsing, the character whose name and role as Dracula's foe - and nothing else - inspired the former.
Kyūketsuki Hantā Dī, or Vampire Hunter D, was first published in 1983, predating Van Helsing by twenty-one years.
Solomon Kane first appeared in the August 1928 issue of Weird Tales, in the story "Red Shadows," one of the first Sword-and-Sorcery tales. It predates Vampire Hunter D by fifty-five years, and Van Helsing by seventy-six years.
The next person who says Solomon Kane is a Vampire Hunter D ripoff or unofficial sequel to Van Helsing, is going to get shot by a cannon.