Meme stock Bed Bath & Beyond Inc. /zigman2/quotes/209801102/composite BBBY -5.92% soared another 22% in premarket trade Wednesday, extending its prior-day gains and a winning streak that has seen it gain 59% in the week to date. Tuesday's rally came even as yet another Wall Street analyst downgraded the stock to sell and warned investors of "unrealistic" valuations. "BBBY has recently gained the attention of retail traders in the Wall Street Bets Reddit forum again, which gained notoriety during the GameStop saga back in January 2021," B.Riley analyst Susan Anderson wrote in a note to clients. "We believe BBBY is currently trading at unrealistic valuations." GameStop Corp. /zigman2/quotes/203755179/composite GME +1.38% stock was up 1.3% premarket. Other recent meme stock successes were lower, with AMC Entertainment Holdings Inc. /zigman2/quotes/200235402/composite AMC +1.78% down 0.3% and bankrupt cosmetics company Revlon Inc. /zigman2/quotes/207032377/composite REV -1.67% down 1.5%.