Kuslima Shogen, chief executive officer and scientific founder of Alfacell Corp., will retire from the company on or before March 31, 2009. The company also announced that the royalty agreement between Ms. Shogen and Alfacell has been terminated.      The termination of the royalty agreement could reduce payments to Ms. Shogen by an estimated $20 million during the next 10 years, if the company’s lead compound Onconase, is granted marketing approval by the FDA.     Under the terms of...