Why Apellis Pharmaceuticals Stock Was Tumbling on Tuesday

Sales of the company's top commercialized product didn't meet expectations.Tuesday's big news with Apellis Pharmaceuticals (APLS -1.70%) wasn't all that favorable to the company. It released its third-quarter results, and the market wasn't all that pleased with the figures.In late-session trading, investors were selling out of Apellis, to the point where its price was down by nearly 6%. By contrast, the S&P 500 (^GSPC 1.23%) index was comfortably in positive territory, with a more than 1% gain at that stage ...