The 2018 West Virginia legislature passed HB 4434, to make it clear that people who lose a primary (for office other than president) can’t petition onto the general election ballot. See this story, which says that it doesn’t go into effect for 90 days after it was signed. It was signed on March 22, so it won’t be in effect until late June.
But Don Blankenship, who ran for U.S. Senate in the Republican primary for U.S. Senate this year, might want to petition as an independent. Whether the old law would block him is not clear.