MEDICAL RESEARCH INVESTMENT FUND, INC.
                           SUPPLEMENT DATED JULY 23, 1996 
                       TO PROSPECTUS DATED DECEMBER 29, 1995


     At a meeting held July 17, 1996, the Board of Directors of Medical Research
Investment Fund, Inc. ("Fund") approved the following proposals, several of
which are subject to approval of Fund shareholders at a meeting to be held
August 29, 1996:

1.   To change the Fund's structure to a "hub-and-spoke" (TM) arrangement,
     subject to shareholder approval.  Under this arrangement, the Fund, as
     "spoke," would have a new investment policy to invest all its investable
     assets in a corresponding "hub" portfolio having substantially the same
     investment objective, policies and restrictions as the Fund.  The Fund's
     current investment adviser, G/A Capital Management ("G/A"), would become
     investment adviser to the hub pursuant to a new investment advisory
     agreement with the hub.  The new investment advisory agreement would retain
     the current advisory fee schedule but would (a) add additional breakpoints
     (reductions) applicable at such time as the Fund's assets reach $500
     million and (b) would add a performance fee providing for fees to G/A to be
     increased or decreased in the event the hub over- or under-performs the
     Standard & Poor's Index of 500 Common Stocks for the preceding 36-month
     period.

2.   To replace the Fund's present administrator, Capstone Asset Management
     Company, with Eaton Vance Management; and to replace the Fund's present
     distributor, Capstone Asset Planning Company, with Eaton Vance
     Distributors, Inc.  The Eaton Vance organization, founded in 1924 and based
     in Boston, advises, administers and distributes more than 150 mutual funds
     investing in more than 60 different investment portfolios with assets of
     over $16 billion.  In connection with this change, the Fund's shares will
     be sold with a maximum 4.75% front-end sales charge.  Shareholders of
     record on the effective date of the restructuring will be permitted to
     purchase additional shares of the Fund with no sales charge for as long as
     they remain shareholders.

3.   To nominate six new directors to replace the Fund's current Board, which
     would resign.  The new directors must be elected by shareholders.

4.   To eliminate, reclassify and amend certain of the Fund's fundamental and
     non-fundamental investment restrictions, subject to shareholder approval.
     The changes are intended primarily to reflect current applicable regulatory
     requirements.

     If shareholders approve the proposed changes, Eaton Vance has agreed to
maintain the Fund's total expenses to ensure that they do not exceed 2.0% of the
Fund's average daily net assets through August 31, 1999.

     These changes will be described in greater detail in a proxy statement to
be distributed shortly to shareholders.