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MFS(R) INSTITUTIONAL TRUST
MFS(R) INSTITUTIONAL LARGE CAP GROWTH FUND
Supplement to the Current Prospectus
The description of portfolio managers under the "Management of the Funds -
Investment Adviser" section is hereby restated as follows:
Large Cap Growth Fund - Stephen Pesek and S. Irfan Ali, Vice
Presidents of the Adviser are the Fund's portfolio managers. Mr. Pesek
has been employed as a portfolio manager by the Adviser since 1994.
Mr. Ali has been employed as a portfolio manager by the Adviser since
1993.
The date of this Supplement is March 5, 1999.
