Biogen memo examined

US federal investors are examining a memo to see what officials at Biogen Idec Inc, the third-largest US biotechnology company, knew about the condition of two patients before the withdrawal of the drug Tysabri, the Wall Street Journal reported.

Securities and Exchange Commission investigators were trying to see if and when four executives involved in selling options in February knew about the condition of two patients given the drug as part of a clinical trial, the Journal said.

The memo indicated that the patients first developed symptoms of a rare brain disorder in December, before undergoing tests in February; one died that month and the second is showing signs of improvement. Tysabri, used for treating multiple sclerosis, was withdrawn on February 28, the day the memo was written, the paper said.

The Securities and Exchange Commission is probing sale of Biogen shares by four executives between February 14 and 18, the Journal said. The shares fell nearly 43% on February 28.

Two officials, named by the Journal, sold their share options on February 14 and 15 within a pre-planned program; two others sold outside the program but denied the sales were made in the knowledge that any patient had developed the brain disease progressive multifocal leukoencephalopathy (PML) the WSJ said, citing a company spokeswoman.