MIRAVANT MEDICAL TECHNOLOGIES

                                336 Bollay Drive

                             Santa Barbara, CA 93117

                                                     August 4, 1999



Via Facsimile *****
and Federal Express

Mr. Michael D. Farney
*****

         Re:      Miravant Medical Technologies ("Miravant")

Dear Mike:

     This letter  agreement  (the  "Letter  Agreement")  will reflect our mutual
agreement regarding Miravant's guaranty of your Sanwa Bank ("Sanwa") loan.

     1. You agree that the properties  listed below (the  "Properties")  will be
immediately put up for sale at their appraised  values based on an MAI appraisal
or other appraisal  acceptable to Miravant,  and you will provide  Miravant with
copies of the  appraisals  on the  Properties  as well as copies of the  Listing
Agreements.  All proceeds from the sale of any of the Properties will be used to
pay down the Sanwa Loan. If the Properties have not been sold within one hundred
twenty (120) days from the date of this Letter  Agreement,  you will immediately
reduce the selling prices to prices which, in the opinion of the listing broker,
will lead to a sale but not less than a reduction of ten percent (10%) following
each  additional  ninety  (90)  days,  and  reoccurring  each  ninety  (90) days
thereafter that the Properties remain unsold, either by the owner or the broker,
or you have made the *****  pay-down by another  means.  You will  pay-down  the
Sanwa Loan by ***** through the refinancing of the Properties or by other means.
If you do secure such refinancing, then you need not sell the Properties.

     2. You will  grant  Miravant a Second  Trust Deed on each of the  following
Properties,  and in the case of the vacant lot, a First Trust Deed. Miravant has
terminated the request for a Trust Deed on your ***** residence  subject to this
matter  being  resolved  immediately.  You  represent  that the  status of these
Properties are as follows:

***** Confidential Treatment Requested



                          Debt              Cost             Acquisition
                                                                Date

         *****

(collectively, the "Properties").

     3. You will grant Miravant a security interest in the *****
Promissory Note.

     Any proceeds from that asset will be immediately applied to the Sanwa Loan.
You will also sign a Form UCC-1 regarding the White Plains Promissory Note.

     4. You  hereby  consent to the  transfer  by Sanwa of  Miravant  shares for
payment to Miravant of its original  Credit  Enhancement  Fee of 4,343 shares of
Miravant stock in accordance with the  Indemnification  Agreement dated February
27, 1998 (the "Indemnification Agreement").

     5. *****

     6. *****

     7. For the foregoing accommodations,  you will pay to Miravant, in Miravant
shares held by Sanwa, an Extension Fee of Two Percent (2%) of the balance of the
Sanwa Loan, payable in cash, or shares of Miravant stock,  valued as of the last
sale on the trading day prior to the execution of this Letter  Agreement,  which
is payable upon the execution of this Letter Agreement.

     8. Miravant will ask Sanwa to continue its forbearance and extend the Sanwa
Loan, and would also agree to continue to guaranty your obligations to Sanwa for
a period of one year from July 31, 1999,  subject to your timely  performance of
all obligations to Sanwa or to Miravant.

     9. Time is of the  essence  in this  matter  since it  cannot  be  resolved
overnight,  and we  need  your  immediate  agreement  so  that  you  can  secure
appraisals on the real estate and we can take steps  necessary to implement this
transaction,  including  securing  the  approval  of  Pharmacia & Upjohn to this
transaction as well as Miravant's Board of Directors.

     10. You ratify and confirm the Indemnification Agreement including, without
limitation,  the General Release  contained in Paragraph 13 thereof,  which will
now apply to all matters through the date of this Letter Agreement.

     11. You will  either pay  Miravant,  or  authorize  Sanwa to pay  Miravant,
shares in an amount equal to Miravant's legal fees and costs which are estimated
to be not more than $5,000.

     12. You hereby authorize  Miravant to view credit reports on you,  obtained
by Sanwa.

     Please indicate your agreement to the foregoing by signing in the space set
forth below.


***** Confidential Treatment Requested


                         Very truly yours,

                         MIRAVANT MEDICAL TECHNOLOGIES

                         By:      /s/       Gary S. Kledzik
                                  -------------------------
                                  Gary S. Kledzik,
                                  Chairman





         We agree to the foregoing.



Date:    August 5, 1999           /s/ Michael D. Farney
                                  ---------------------
                                  MICHAEL D. FARNEY


Date:    August 5, 1999           /s/ Sally Farney
                                  ---------------------
                                  SALLY FARNEY


***** Confidential Treatment Requested