Exhibit 10.1

AGREEMENT

 

Until  the earlier of 12:00 p.m. noon Eastern time on August 20, 2003 or the
termination of this letter agreement by Xmark in accordance with the next
sentence, Photogen Technologies, Inc. (“Photogen”) agrees that it will not file
any court actions (including any petition under bankruptcy, insolvency or
debtor’s relief law) directed to prevent Xmark Fund, Ltd. and/or Xmark Fund,
L.P. (collectively, “Xmark”) from exercising their rights or remedies as a
secured creditor nor will Photogen take any action (or omit to take any action)
that is in breach or contravention of the Security Agreement, dated June 18,
2003 (the “General Security Agreement”), by and among Photogen and Xmark or the
Patent and Trademark Security Agreement, dated June 18, 2003 (the “IP Security
Agreement” and together with the General Security Agreement, the “Security
Agreements”), by and among Photogen and Xmark (solely for purposes of this
letter agreement, the existing payment default by Photogen shall not be deemed
to be a breach or contravention of the Security Agreements that would entitle
Xmark to accelerate the expiration of the forbearance period).  Xmark agrees
that it will forbear from foreclosure of its liens or otherwise exercising
whatever rights and remedies it has as a secured creditor of Photogen until the
earliest to occur of (i) 12:00 p.m. noon Eastern time on August 20, 2003, (ii)
any creditor of Photogen taking any action to execute on the collateral securing
Xmark’s liens, (iii) Photogen’s failure to comply in all respects with the
covenants set forth in the preceding sentence or (iv) the termination of
discussions between Xmark and Photogen concerning the proposed agreement to cure
Photogen’s existing payment default.  Xmark will not foreclose its liens or
exercise such other remedies prior to 12:00 p.m. noon Eastern time on August 20,
2003 as a result of any event covered by clause (ii) or (iii) of the preceding
sentence unless it gives Photogen written notice of its intention to do so prior
to taking any such action. A copy of any such notice to Photogen shall be
delivered by fax to John Monaghan, Esq., Holland & Knight, Fax number
617/523-6850.  This letter agreement shall not be deemed to be a waiver of any
defaults or a waiver of any rights or remedies by Xmark.

 

PHOTOGEN TECHNOLOGIES, INC.

 

By:

 

/s/ Taffy Williams

             Taffy Williams

 

XMARK FUND, L.P.

 

By:

 

/s/ Mitchell Kaye

              Mitchell D. Kaye, Chief  Investment Officer

 

XMARK FUND, LTD.

 

By:

 

/s/ Mitchell Kaye

             Mitchell D. Kaye, Chief  Investment Officer

 

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