Biotech company Biogen has announced the sudden departure of its executive vice president Thomas J. Bucknum.
Mr Bucknum's sudden departure comes nearly two weeks after Biogen and Elan withdrew the Multiple Sclerosis drug Tysabri after it emerged that the drug was linked to a rare disease that killed one patient and was contracted by another.
The SEC has begun an investigation into Mr Buckum's sale of 89,700 shares of Biogen stock on February 18th, just before the company announced the bad news about Tysabri.
According to documents the company filed with the SEC, Mr Bucknum netted about $1.9 million from the sale.
A string of recent shareholder lawsuits charge Biogen violated securities laws by allegedly failing to disclose that Tysabri could raise vulnerability to PML, a central nervous system disorder.
Biogen chairman William H. Rastetter also sold shares prior to the withdrawal of Tysabri, although his sale was made on February 15th. Mr Rastetter sold 120,313 shares, netting $7.7 million. The company said Bucknum will not receive severance compensation.