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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 section entitled "Prospectus Summary-Advisory Fee" and the fourth
paragraph of the section entitled "Investment Advisory Agreement" in the above
Prospectus are revised to reflect that, effective May 1, 2000, the Trustees of
the Trust have amended the Trust's Investment Advisory Agreement to reduce the
compensation received by the Investment Advisor under the Agreement for assets
exceeding $3 billion, so that the compensation under the Agreement is
calculated daily by applying the following annual rates to the Trust's net
assets determined as of the close of each business day: 0.90% of the portion of
daily net assets not exceeding $500 million; 0.85% of the next $1 billion;
0.825% of the next $1 billion; 0.80% of the next $500 million; and 0.775% of
the portion of daily net assets exceeding $3 billion.
May 1, 2000
