TENBY PHARMA INC
EX-10.31  PROMISSORY NOTE
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<TYPE>EX-10.31
<SEQUENCE>33
<FILENAME>g03213exv10w31.htm
<DESCRIPTION>EX-10.31  PROMISSORY NOTE
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<DIV align="right" style="font-size: 10pt; margin-top: 12pt"><B>Exhibit&nbsp;10.31</b>
<DIV align="right" style="font-size: 10pt; margin-top: 6pt"><b>EXECUTION VERSION</B>
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<DIV align="center" style="font-size: 10pt; margin-top: 18pt"><B>PROMISSORY NOTE</B>
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<DIV align="center">
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    <TD align="left" valign="top">$5,000,000
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    <TD>&nbsp;</TD>
    <TD align="right" valign="top">February&nbsp;14, 2006</TD>
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<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;FOR VALUE RECEIVED, SIRION THERAPEUTICS, INC., a North Carolina corporation
(&#147;Borrower&#148;), hereby promises to pay to the order of PHARMABIO DEVELOPMENT INC., a North Carolina
corporation (&#147;Lender&#148;), in lawful money of the United States of America in immediately available
funds, the lesser of (i)&nbsp;the principal sum of Five Million ($5,000,000) and (ii)&nbsp;the aggregate
unpaid principal amount of all Advances (as defined in the Loan Agreement referred to below) made
by Lender to Borrower pursuant to the Loan Agreement (as defined below), together with interest
accrued thereon. The interest shall accrue on the unpaid principal amount of each Advance at the
rates and in the manner provided in the Loan Agreement. Payment of the principal amount of this
Note and accrued interest on this Note shall be made at the times and in the manner provided in the
Loan Agreement. Capitalized terms used but not defined herein shall have the meanings ascribed to
them in the Loan Agreement.
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<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Each Advance made by Lender to Borrower, and all payments made on account of the principal
amount hereof, shall be recorded and endorsed by Lender on the grid attached hereto which is a part
of this Note. Failure to so record and endorse such Advances and payments, however, shall not
affect Borrower&#146;s obligations in respect of such Advances.
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<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;This Promissory Note is the Note referenced in the Loan Agreement between Borrower and Lender
dated as of the date of this Note (as same may be amended from time to time, the &#147;Loan Agreement&#148;),
and is entitled to the benefits of the Loan Agreement. The Loan Agreement, among other things, (i)
provides for the making of certain Advances by Lender to Borrower from time to time, the principal
amount of each such Advance being a principal amount evidenced by this Note, and (ii)&nbsp;provides that
this Note is secured by, and Borrower has granted a security interest in, certain of its assets as
set forth in that certain Security Agreement between Borrower and Lender dated as of the same date
as this Note.
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<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In case an Event of Default (as defined in the Loan Agreement) shall occur and be continuing,
the unpaid principal amount of, and accrued interest on, this Note may be declared to be due and
payable in the manner and with the effect provided in the Loan Agreement.
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<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Borrower hereby waives presentment, demand, notice, protest and all other demands and notices
in connection with the delivery, acceptance, performance and enforcement of this Note.
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<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;This Note shall be governed by and construed in accordance with the Laws of the State of North
Carolina without regard to the conflicts of law rules of such state.
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<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Lender and Borrower agree that disputes relating to this Note shall be subject to the
provisions of the Loan Agreement entitled &#147;Internal Review&#148; and &#147;Arbitration&#148; set forth in Sections
8.14 and 8.15 thereof, respectively.
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    <TD colspan="3" valign="top" align="left">BORROWER:</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
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    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
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    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
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    <TD valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD colspan="3" valign="top" align="left">SIRION THERAPEUTICS, INC.</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
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    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
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    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;
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    <TD>&nbsp;</TD>
    <TD align="left" valign="top">By:
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">/s/ Barry Butler</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
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    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;
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    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Name:
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><DIV style="font-size: 1pt; border-top: 1px solid #000000">&nbsp;</DIV>
Barry Butler
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
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    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Title:
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">CEO</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
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