Shares of Impax Laboratories Inc. (IPXL) soared 13.2% to $24.40 in afternoon trading on Thursday, Sept. 21, following a report by the Wall Street Journal that the drug maker is in merger discussions with closely held Amneal Pharmaceuticals LLC.

A deal could materialize next month, the report said, citing people familiar with the matter.

An Impax spokesperson said the company does not comment on rumors. An Amneal representative said the firm does not comment on rumor or innuendo.

The report came after China's Shanghai Fosun Pharmaceutical (Group) Co. Ltd. disclosed a passive 5.19% stake in Impax on Aug. 31.

Impax on Aug. 9 reported second-quarter adjusted income per share of $0.18, compared with $0.21 in the year-ago period. Revenue grew 17.1% year-over-year to $202.1 million.

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