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                                                                  EXHIBIT 10.111

                                 AMENDMENT NO. 4
                                     TO THE
             STRUCTURED EQUITY LINE FLEXIBLE FINANCING(SM) AGREEMENT

         THIS AMENDMENT NO. 4 to the STRUCTURED EQUITY LINE FLEXIBLE
FINANCING(SM) AGREEMENT ("Amendment") is dated as of October 27, 2000 between
Cripple Creek Securities, LLC, a limited liability company organized and
existing under the laws of the state of New York (the "Investor"), and Cygnus,
Inc., a corporation organized and existing under the laws of the State of
Delaware (the "Company"). Capitalized terms not defined herein shall have the
meanings assigned to them in that certain Structured Equity Line Flexible
Financing(SM) Agreement dated as of June 30, 1999, as amended September 29,
1999, March 27, 2000 and May 9, 2000 (the "Agreement").

                              W I T N E S S E T H:
                              - - - - - - - - - -

         WHEREAS, the Company and the Investor entered into the Agreement,
pursuant to which the Company may issue to the Investor, and the Investor shall
purchase from the Company, from time to time as provided therein, shares of the
Company's common stock, par value $.001 per share, for a maximum aggregate
Purchase Price of $60,000,000; and

         WHEREAS, the Company and the Investor desire to amend the Agreement in
certain respects.

         NOW, THEREFORE, in consideration of the foregoing premises and other
good and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto agree as follows:


                                    ARTICLE I

                                    AGREEMENT

         Section 1.1 Section 2.2(b) of the Agreement is hereby amended and
restated in its entirety as follows:

         "(b) INVESTMENT PERIOD LIMITS. Notwithstanding the obligations and
rights of the Investor to purchase shares of Common Stock pursuant to Section
2.1 (b), (c) and (d), the aggregate Investment Amount for any Investment Period
(whether pursuant to a Minimum Obligation, an Additional Purchase Notice or an
Investor Call Purchase Notice or any combination thereof) shall not at the
option of the Investor exceed the lesser of (x) the Minimum Obligation plus the
amount set forth in any Additional Purchase Notice and Investor Call Purchase
Notice with respect to such Investment Period, if any, or (y) an amount equal to
8% of the aggregate Value of Open Market Trading of the Common Stock on the
Principal Market for each Trading Day during the Investment Period immediately
preceding such Investment Period on which the Stock Price is above the Floor
Price (rounded up to the next increment of $10,000), or (z) an amount equal to
8% of the aggregate Value of Open Market Trading of the Common Stock on the
Principal Market for each Trading Day during such Investment Period on which the
Stock Price is above the Floor Price (rounded up to the next increment of
$10,000) (the lower of the amounts referred to in clauses (y) and (z), the "8%
Limit"); provided, however, that the Investor may waive, in whole or in part,
the 8% Limit in any Investment Period."

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                                   ARTICLE II

                                  MISCELLANEOUS

         Section 2.1 NO THIRD PARTY BENEFICIARIES. This Amendment is intended
for the benefit of the parties hereto and their respective permitted successors
and assigns and is not for the benefit of, nor may any provision hereof be
enforced by, any other person.

         Section 2.2 GOVERNING LAW. This Amendment shall be governed by and
construed and enforced in accordance with the internal laws of the State of New
York without regard to such state's principles of conflict of laws.

         Section 2.3 EXECUTION. This Amendment may be executed in two or more
counterparts, all of which shall be considered one and the same agreement, it
being understood that all parties need not sign the same counterpart.

         Section 2.4 AGREEMENT OTHERWISE UNCHANGED. Except as amended hereby and
previously, the Agreement shall remain unchanged and in full force and effect.


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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment No. 4
to the Structured Equity Line Flexible Financing(SM) Agreement to be duly
executed by their respective authorized officers as of the date hereof.

CRIPPLE CREEK SECURITIES, LLC             CYGNUS, INC.



By:    /s/ ROBERT L. CHENDER              By:    /s/ CRAIG W. CARLSON
     ------------------------------            ---------------------------------
     Name:  Robert L. Chender                  Name: Craig W. Carlson
     Title:  Principal                         Title: Senior VP, Fiananc and CFO







        [SIGNATURE PAGE TO AMENDMENT NO. 4 TO THE STRUCTURED EQUITY LINE
                          FLEXIBLE FINANCING AGREEMENT]


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