The board of Sirtex decided to terminate Wong's contract effective immediately last Friday after reviewing a report from legal advisers Watson Mangioni.
The company commissioned the law firm to investigate Wong's share trading activities after investor and ASX enquiries about the performance of the company.
In a statement to the market, the company says, "After due consideration, the Board of Sirtex has today terminated Mr Wong's employment with Sirtex, with immediate effect."
"Mr Wong's salary and statutory entitlements will be paid to the date of termination. All unvested performance rights previously issued to Mr Wong have been forfeited."
The contents of the report are privileged and confidential.
In October last year, Wong sold more than $2 million of his shares in the company.
Since Wong sold out of the company, Sirtex shares have fallen in dramatic fashion. In particular, the company's share price halved from around $28 to $14 when Sirtex released a revised trading update on December 9 which warned of slower than expected sales.
Current chief cperating officer, Nigel Lange, has replaced Wong as the acting chief executive officer of Sirtex.
Lange says he is looking forward to "delivering on our strategies, to maximise the potential of our SIR-Spheres microspheres technology, and to reinstate value to our shareholders."
Sirtex says it will be conducting an extensive executive search and recruitment process to fill the chief executive position and intends to appoint an executive search firm to oversee this process.
Sirtex is an Australian-based global healthcare business focused on cancer treatments.
The company's share price at 1.30 pm AEST is at $15.83, down by 2 cents from the commencement of trading today.
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