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Filed Pursuant to Rule 497(e)
Registration File No.: 333-67701
SUPPLEMENT TO THE PROSPECTUS OF
MORGAN STANLEY DEAN WITTER PRIME INCOME TRUST
DATED DECEMBER 20, 1999
The second paragraph of the section entitled "Determination of Net Asset
Value" in the Prospectus is hereby replaced by the following:
Senior Loans that meet certain pricing criteria are valued based on
quotations received from an independent pricing service. Senior Loans that
do not meet these pricing parameters generally are valued based on prices
received from an independent pricing service that are calculated pursuant
to a derived pricing methodology. The derived pricing methodology
calculates a price for a Senior Loan by incorporating certain market
information, including a Senior Loan's credit rating and interest rate,
and comparing such information to Senior Loans in similar industries for
which market information is available. All other Senior Loans are valued
at their fair value in accordance with procedures established in good
faith by the Board of Trustees of the Trust.
November 6, 2000
