BOSTON (MarketWatch) -- Shares of Human Genome Sciences HGSI -21.13% sank 20% to $10.18 the day after the biotech firm reported weaker-than-expected sales of its new lupus drug Benlysta. According to analysts at Leerink Swann on Wednesday, Benlysta's net sales of $18.8 million for the quarter were in line with its lowered estimate of $19 million, but about 6% below the Wall Street consensus of $20.1 million. The first drug approved to treat lupus in over 50 years, industry watchers have estimated that Benlysta could be a blockbuster. As a result, Human Genome shares have been pushed markedly higher in recent weeks on rumors that it might be bought by Benlysta's co-marketer, GlaxoSmithKline PLC GSK +0.45% , for around $25 a share.
BLT Price at posting:
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