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                                                                     EXHIBIT 3.7

                   CERTIFICATE OF DESIGNATIONS, PREFERENCES
                    AND RIGHTS OF SERIES B PREFERRED STOCK

                                      of

                              GENAERA CORPORATION

            Pursuant to Section 151 of the General Corporation Law
                           of the State of Delaware


          The undersigned, Vice President and Chief Financial Officer of Genaera
     Corporation, a Delaware corporation (hereinafter called the "Corporation"),
     pursuant to the provisions of Sections 103 and 151 of the Delaware General
     Corporation Law (the "DGCL"), does hereby make this Certificate of
     Designations and does hereby state and certify that pursuant to the
     authority expressly vested in the Board of Directors of the Corporation by
     the Certificate of Incorporation, the Board of Directors duly adopted the
     following resolutions:

          RESOLVED, that, pursuant to Section A(1) of the Certificate of
     Incorporation (which authorizes 9,211,031 shares of convertible preferred
     stock, $.001 par value ("Preferred Stock"), of which 80,000 shares have
     been designated Series A Convertible Preferred Stock (the "Series A
     Preferred Stock") and of which 1,188 shares of Series A Preferred Stock are
     currently issued and outstanding), the Board of Directors hereby fixes the
     powers, designations, preferences and relative, participating, optional and
     other special rights, and the qualifications, limitations and restrictions,
     of a series of Preferred Stock.

          RESOLVED, that each share of such series of Preferred Stock shall rank
     equally in all respects and shall be subject to the following provisions:

          1.   Number and Designation. 10,000 shares of the Preferred Stock of
     the Corporation shall be designated as Series B Convertible Preferred
     Stock, $.001 par value (the "Series B Preferred Stock").

          2.   Rank. The Series B Preferred Stock shall, with respect to
     dividend rights and rights on liquidation, dissolution and winding up, rank
     prior to the Corporation's common stock, $.002 par value ("Common Stock")
     and rank junior to the Series A Preferred Stock. All equity securities of
     the Corporation to which the Series B Preferred Stock ranks prior (whether
     with respect to dividends or upon liquidation, dissolution, winding up or
     otherwise), including the Common Stock, are collectively referred to herein
     as the "Junior Securities." All equity securities of the Corporation with
     which the Series B Preferred Stock ranks on a parity are collectively
     referred to as "Parity Securities" and all equity securities of the
     Corporation to which the Series B Preferred Stock ranks junior (whether
     with respect to dividends or upon liquidation, dissolution or winding up)
     are collectively referred to herein as the "Senior Securities." The
     respective
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     definitions of Junior Securities and Senior Securities shall also include
     any rights or options exercisable for or convertible into any of the Junior
     Securities and Senior Securities, as the case may be. The Series B
     Preferred Stock shall be subject to the creation of Junior Securities but
     not subject to the creation of Senior Securities except as provided in
     paragraph 6(a) hereof.

          3.   Dividends.

               (a)  In the event that the Corporation declares a dividend with
          respect to or makes a distribution on the Common Stock, then the
          holders of the Series B Preferred Stock shall be entitled to
          participate with the holders of the Common Stock in any such dividends
          or distributions paid or set aside for payment, such that the holders
          of the Series B Preferred Stock shall receive, with respect to each
          share of Series B Preferred Stock held, an amount equal to (i) the
          dividend or distribution payable with respect to each share of Common
          Stock, multiplied by (ii) the number of shares of Common Stock into
          which such share of Series B Preferred Stock is convertible as of the
          record date for such dividend or distribution. The provision of this
          subsection 3(a) shall not apply to any dividends or distributions that
          would result in an adjustment of the Series B Conversion Price (as
          hereinafter defined) pursuant to Section 5(g).

               (b)  For purposes of this Section 3, unless the context requires
          otherwise, "distribution" shall mean the transfer of cash or property
          without consideration, whether by way of dividend or otherwise,
          payable other than in Common Stock or other securities of the
          Corporation, or the purchase or redemption of shares of the
          Corporation (other than repurchases of Common Stock held by employees
          of, or consultants to, the Corporation upon termination of their
          employment or services pursuant to agreements providing for such
          repurchase or other than redemptions in liquidation or dissolution of
          the Corporation) for cash or property, including any such transfer,
          purchase, or redemption by a subsidiary of the Corporation.

          4.   Liquidation Preference.

               (a)  In the event of any liquidation, dissolution or winding up
          of the Corporation, prior and in preference to any distribution of any
          of the assets or funds of the Corporation to the holders of Series B
          Preferred Stock and any Junior Securities by reason of their ownership
          of such stock, the holders of Series A Preferred Stock shall be
          entitled to receive for each outstanding share of Series A Preferred
          Stock then held by them an amount equal to $1,000.00 (the "Series A
          Liquidation Preference") plus accrued and unpaid cumulative dividends
          on such share (as adjusted for any recapitalizations, stock
          combinations, stock dividends, stock splits and the like). Following
          the payment of the Series A Liquidation Preference, and prior and in
          preference to any distribution of any of the assets or funds of the
          Corporation to the holders of Junior Securities by reason of their
          ownership of such stock, the holders of Series B Preferred Stock shall
          be entitled to receive for each outstanding share of Series B
          Preferred Stock then held by them in an amount equal to $1,000.00 (the
          "Series B Liquidation Preference")

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          plus any declared but unpaid dividends on such shares (as adjusted for
          any recapitalizations, stock combinations, stock dividends, stock
          splits and the like). If, upon the occurrence of a liquidation,
          dissolution or winding up, the assets and funds of the Corporation
          legally available for distribution to stockholders by reason of their
          ownership of stock of the Corporation shall be insufficient to permit
          the payment of the full aforementioned preferential amount on the
          Series B Preferred Stock, then the entire assets and funds of the
          Corporation legally available for distribution to stockholders by
          reason of their ownership of stock of the Corporation shall be
          distributed among the holders of Series B Preferred Stock and holders
          of any other such Parity Securities ratably in accordance with the
          respective amounts that would be payable on such shares of Series B
          Preferred Stock and such Senior Securities if the amounts payable
          thereon were paid in full.

               (b)  Subject to the prior rights of the holders of any Senior
          Securities, after payment shall have been made in full to the holders
          of the Series B Preferred Stock, as provided in this Section 4, any
          other series or class or classes of Junior Securities shall, subject
          to the respective terms and provisions (if any) applying thereto, be
          entitled to receive any and all assets remaining to be paid or
          distributed, and the holders of the Series B Preferred Stock shall not
          be entitled to share therein.

          5.   Conversion.

               (a)  Conversion of Series B Preferred Stock.

                    (i)  Each share of Series B Preferred Stock shall be
               convertible prior to April 19, 2006 at the option of the holder.
               Beginning on April 19, 2006, each share of Series B Preferred
               Stock will be convertible, at either the option of the holder
               thereof or the option of the Corporation, subject to the
               limitation set forth in paragraph 5(a)(ii), whichever first
               delivers a notice of conversion pursuant to paragraph 5(c) or
               paragraph 5(d) as the case may be.

                    (ii) The Corporation may not provide notice of its intention
               to convert any shares of Series B Preferred Stock if the closing
               bid price of the Common Stock as quoted on the Nasdaq National
               Market, or any other established exchange or national system on
               which the Common Stock is listed, for the day prior to the date
               of such proposed notice is less than the Closing Common Stock
               Price. The "Closing Common Stock Price" shall be the average
               closing bid price of the Common Stock as quoted on the Nasdaq
               National Market, or any other established exchange or national
               system on which the Common Stock is listed, over the 20 Trading
               Days prior to the Closing Date as such term is defined in the
               Preferred Stock Purchase Agreement dated April 19, 2001 (the
               "Purchase Agreement") by and between the Corporation and
               MedImmune, Inc. ("MedImmune").

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                    (iii) If there shall be (A) any merger or consolidation of
               the Corporation with or into any other corporation or
               corporations in which the Corporation is not the continuing or
               surviving corporation or pursuant to which the Common Stock would
               be converted into cash, securities and/or other rights or assets,
               or (B) any sale or conveyance of all or substantially all of the
               assets of the Corporation, (collectively, a "Merger Event"), then
               immediately prior to the consummation of such Merger Event, each
               share of Series B Preferred Stock shall be automatically
               converted without any action to be taken by the Corporation or a
               holder.

               (b)  Determination of Number of Shares of Common Stock to be
          Issued Upon Conversion.

                    (i)   If converted by a holder of Series B Preferred Stock
               prior to April 19, 2006, each share of Series B Preferred Stock
               shall be convertible into two hundred (200) fully paid and non-
               assessable shares of Common Stock, subject to adjustment as
               provided in Section 5(g)(i) hereof.

                    (ii)  If converted by a holder of Series B Preferred Stock
               or the Corporation on or subsequent to April 19, 2006, or if
               automatically converted at any time as a result of a Merger
               Event, each share of Series B Preferred Stock shall be
               convertible into such number of fully paid and non-assessable
               shares of Common Stock as is determined by dividing the Series B
               Original Issue Price of such share of Series B Preferred Stock by
               the Series B Conversion Price at the time in effect for a share
               of Series B Preferred Stock. The "Series B Original Issue Price"
               per share of Series B Preferred Stock is $1,000.00. The "Series B
               Conversion Price" per share of Series B Preferred Stock shall be
               the lesser of (A) $5.00 and (B) the average closing bid price of
               the Common Stock as quoted on the Nasdaq National Market, or any
               other established exchange or national system on which the Common
               Stock is listed, in the twenty (20) Trading Days preceding the
               Conversion Date (defined below) or, if automatically converted
               upon a Merger Event, the twenty (20) Trading Days preceding the
               closing of the Merger Event; provided that in no event shall the
               Series B Conversion Price per share of Series B Preferred Stock
               be less than the Closing Common Stock Price. "Trading Day," as
               used herein, shall mean a day on which the Nasdaq National
               Market, or any other established exchange or national system on
               which the Common Stock is listed, is open for trading.

               (c)  Notice of Conversion by the Holders. In order to convert the
          Series B Preferred Stock into Common Stock, the holder of the Series B
          Preferred Stock shall deliver to the Corporation a notice of its
          election to make such conversion at least five (5) business days prior
          to the intended date of conversion (the "Conversion Date") setting
          forth (i) the Conversion Date, (ii) the number of shares of Series B
          Preferred Stock to be converted on the Conversion Date, (iii)

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          the number of shares of Common Stock held by such holder and (iv) the
          names (and addresses) in which the certificates for shares of Common
          Stock issuable upon conversion shall be issued. With respect to any
          conversion by a holder of Series B Preferred Stock on or subsequent to
          April 19, 2006, such holder shall not sell in the market any shares of
          Common Stock held by it during the twenty (20) days preceding the
          Series B Conversion Date.

               (d)  Notice of Conversion by the Corporation. The Corporation can
          exercise its right to have the holders of the Series B Preferred Stock
          convert their shares of Series B Preferred Stock pursuant to Section
          5(a) by mailing a notice of conversion to each holder of record of
          shares of Series B Preferred Stock addressed to the holder at the
          address of such holder appearing on the books of the Corporation or
          given by the holder to the Corporation for the purpose of notice, or,
          if no such address appears or is given, then at the place where the
          principal executive office of the Corporation is located, not later
          than twenty (20) days before the Conversion Date. The notice of
          conversion shall (i) include (A) the Conversion Date and (B) the place
          at which the stockholders may exchange certificates representing their
          shares of Series B Preferred Stock for certificates representing
          shares of Common Stock issuable upon conversion and (ii) state that
          the certificates for shares of Common Stock issuable upon conversion
          shall be issued in the name (and address) of the holder, unless
          instructed otherwise by such holder. The holder of Series B Preferred
          Stock that has had a notice of conversion delivered to it by the
          Corporation shall not sell its shares of Common Stock in the market
          during the twenty (20) days preceding the Conversion Date

               (e)  Limit on Common Stock Issued on Conversion. The aggregate
          number of shares of Common Stock issued on conversion of shares of
          Series B Preferred Stock pursuant to paragraph 5(b)(i) shall be
          2,000,000 (the "First Maximum Conversion Amount"). The aggregate
          number of shares of Common Stock issued on conversion of shares of
          Series B Preferred Stock pursuant to paragraph 5(b)(ii) shall not
          exceed the lesser of 6,508,777 shares and the quotient of $10,000,000
          divided by the Closing Common Stock Price (the "Second Maximum
          Conversion Amount"). In the event that a conversion notice pursuant to
          paragraph 5(c) or paragraph 5(d) provides for the conversion on the
          Conversion Date of shares of Series B Preferred Stock such that the
          sum of the shares of Common Stock previously issued through conversion
          of Series B Preferred Shares and the shares of Common Stock that would
          be issued upon conversion of the number of Series B Preferred Shares
          specified in the conversion notice would exceed the Second Maximum
          Conversion Amount, the number of Series B Preferred Shares specified
          in the conversion notice shall be deemed to be converted for the
          number of Conversion Shares that is the difference between the Second
          Maximum Conversion Amount and the number of Conversion Shares
          previously issued through conversion of Series B Preferred Stock. In
          the event that some but not all of the Series B Preferred Stock are
          specified in a conversion notice seeking conversion pursuant to
          paragraph 5(b)(ii), the number of shares of Common Stock issued in
          such partial conversion shall not exceed the product of the Second
          Maximum Conversion Amount multiplied by the quotient of the

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          number of shares of Series B Preferred Stock specified in the
          conversion notice divided by 10,000.

               (f)  Partial Conversion. In the event that some but not all of
          the Series B Preferred Stock represented by a certificate or
          certificates surrendered by a holder are converted, the Corporation
          shall execute and deliver to or on the order of the holder, at the
          expense of the Corporation, a new certificate representing the number
          of shares of Series B Preferred Stock that were not converted.

               (g)  Adjustments for Stock Splits, Recombinations, etc.

                    (i)  If the Corporation shall at any time or from time to
               time effect a subdivision of the outstanding Common Stock, or
               shall issue a dividend of Common Stock on its outstanding Common
               Stock, the number of shares of Common Stock into which the Series
               B Preferred Stock is convertible pursuant to Section 5(b)(i) then
               in effect immediately before that subdivision or dividend shall
               be proportionately increased and conversely, if the Corporation
               shall combine the outstanding shares of Common Stock, the number
               of shares of Common Stock into which the Series B Preferred Stock
               is convertible pursuant to Section 5(b)(i) then in effect
               immediately before the combination shall be proportionately
               decreased. Any adjustment under this subsection 5(g)(i) shall
               become effective at the close of business on the date the
               subdivision or combination becomes effective or on the date which
               the dividend is declared.

                    (ii) If converted by a holder of Series B Preferred Stock or
               the Corporation on or subsequent to April 19, 2006, the
               Conversion Date shall be subject to adjustment from time to time
               as follows:

                         (A)  In the event the Corporation should at any time or
                    from time to time after the date hereof fix a record date
                    that is less than twenty (20) Trading Days prior to a
                    Conversion Date for the effectuation of a split or
                    subdivision of the outstanding shares of Common Stock or the
                    determination of holders of Common Stock entitled to receive
                    a dividend or other distribution payable in additional
                    shares of Common Stock or other securities or rights
                    convertible into, or entitling the holder thereof to receive
                    directly or indirectly, additional shares of Common Stock
                    (hereinafter, the "Common Stock Equivalents") without
                    payment of any consideration by such holder for the
                    additional shares of Common Stock or the Common Stock
                    Equivalents (including the additional shares of Common Stock
                    issuable upon conversion or exercise thereof), then such
                    Conversion Date shall be extended to the date which is
                    twenty (20) Trading Days after such record date.

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                     (B) In the event the Corporation should at any time or from
               time to time after the date hereof fix a record date which is
               less than twenty (20) Trading Days prior to a Conversion Date for
               a combination of the outstanding shares of Common Stock, then
               such Conversion Date shall be extended to the date which is
               twenty (20) Trading Days after such record date.

               (iii) If the Corporation shall at any time or from time to time
          effect a subdivision of the outstanding Common Stock, or shall issue a
          dividend of Common Stock on its outstanding Common Stock, the $5.00
          maximum Series B Conversion Price set forth in paragraph 5(b)(ii)
          shall be proportionately decreased and conversely, if the Corporation
          shall combine the outstanding shares of Common Stock, the $5.00
          maximum Series B Conversion Price set forth in paragraph 5(b)(ii) and
          the $5.00 shall be proportionately increased. Any adjustment under
          this subsection 5(g)(iii) shall become effective at the close of
          business on the date the subdivision or combination becomes effective
          or on the date which the dividend is declared.

               (iv)  If the Corporation shall at any time or from time to time
          effect a subdivision of the outstanding Common Stock, or shall issue a
          dividend of Common Stock on its outstanding Common Stock, the First
          Maximum Conversion Amount and Second Maximum Conversion Amount set
          forth in paragraph 5(e) shall be proportionately decreased and,
          conversely, if the Corporation shall combine the outstanding shares of
          Common Stock, the First Maximum Conversion Amount and Second Maximum
          Conversion Amount set forth in paragraph 5(e) shall be proportionately
          increased. Any adjustment under this subsection 5(g)(iv) shall become
          effective at the close of business on the date the subdivision or
          combination becomes effective or on the date which the dividend is
          declared.

               (v)   In the event that after the date hereof the Corporation
          shall declare a dividend payable in securities of other persons,
          evidences of indebtedness issued by this Corporation or other persons,
          assets (excluding cash dividends), or options or rights not referred
          to in paragraphs 5(g)(i) through 5(g)(iii), then, in each such case
          each holder of Series B Preferred Stock shall be entitled to a
          proportionate share of any such distribution as though such holder
          were the holder of the number of shares of Common Stock into which
          such holder's shares of Series B Preferred Stock are convertible as of
          the record date fixed for the determination of the holders of Common
          Stock entitled to receive such distribution. For purposes of the
          foregoing, the average closing price of the Common Stock in the five
          (5) Trading Days preceding the record date shall be utilized as the
          Series B Conversion Price.

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                    (vi) If at any time or from time to time after the date
               hereof there shall be a recapitalization of the Common Stock
               (other than a subdivision or combination provided for above in
               this Section 5 (g)), provision shall be made so that each holder
               of Series B Preferred Stock shall thereafter be entitled to
               receive upon any conversion of the Series B Preferred Stock under
               this Section 5 the number of shares of stock or other securities
               or property of the Corporation or otherwise, to which a holder of
               Common Stock deliverable upon conversion of Series B Preferred
               Stock pursuant to this Section 5 would have been entitled on such
               recapitalization. In any such case, appropriate adjustment shall
               be made in the application of the provisions of this Section 5
               with respect to the rights of the holders of Series B Preferred
               Stock after the recapitalization to the end that the provision of
               this Section 5 (including the adjustment in the number of shares
               of Common Stock issuable on conversion) shall be applicable after
               that event as nearly equivalent as may be practicable.

               (h)  Mechanics of Conversion. On the Conversion Date, the holder
          shall surrender the certificates representing the shares of Series B
          Preferred Stock being converted, duly endorsed, to the Corporation at
          its principal office or at the office of its transfer agent. As
          promptly as possible after the Conversion Date, the Corporation shall
          issue and deliver to such holder, such certificates as the holder may
          request for the number of whole shares of Common Stock issuable upon
          the conversion of such shares of Series B Preferred Stock. No
          fractional shares of Common Stock shall be issued upon conversion of
          Series B Preferred Stock. In lieu of any fractional shares to which
          the holder would otherwise be entitled, the Corporation shall pay cash
          equal to such fraction multiplied by the then effective Series B
          Conversion Price of the Series B Preferred Stock. Such conversion
          shall be deemed to have been effected immediately prior to the close
          of business on the Conversion Date, and at such time the rights of the
          holder of the converted shares of Series B Preferred Stock shall
          cease, and the Persons in whose names any certificates of shares of
          Common Stock shall be issuable shall be deemed to have become holders
          of record of the shares of Common Stock represented thereby.

               (i)  Status of Converted Stock. In the event any shares of Series
          B Preferred Stock shall be converted pursuant to this Section 5, the
          shares so converted shall revert to the status of authorized shares of
          Preferred Stock undesignated as to series or other terms.

               (j)  No Impairment. The Corporation will not, by amendment of
          this Certificate of Designations or through any reorganization,
          transfer of assets, consolidation, merger, dissolution, issue or sale
          of securities or any other voluntary action, avoid or seek to avoid
          the observance or performance of any of the terms to be observed or
          performed hereunder by the Corporation, but will at all times in good
          faith assist in the carrying out of all the provisions of this Section
          5 and in the taking of all such action as may be necessary or
          appropriate in order to protect the conversion rights of the holders
          of the Series B Preferred Stock against impairment.

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               (k)  Notices of Record Date. In the event that the Corporation
          shall propose at any time:

                    (i)   to declare any dividend or distribution upon its
               Common Stock, whether in cash, property, stock or other
               securities, whether or not a regular cash dividend and whether or
               not out of earnings or earned surplus;

                    (ii)  to offer for subscription pro rata to the holders of
               Common Stock any additional shares of stock of any class or
               series or other rights;

                    (iii) to effect any reclassification or recapitalization of
               its Common Stock outstanding involving a change in the Common
               Stock; or

                    (iv)  to merge or consolidate with or into any other
               corporation, or sell, lease or convey all or substantially all of
               its property or business, or to liquidate, dissolve or wind up;

               then, in connection with any such event, the Corporation shall
          send to the holders of Series B Preferred Stock

                          (A)  in the case of the matters referred to in (i) and
                    (ii) above, at least ten (10) days prior written notice of
                    the date on which a record shall be taken for such dividend,
                    distribution or subscription rights (and specifying the date
                    on which the holders of Common Stock shall be entitled
                    thereto); and

                          (B)  in the case of the matters referred to in (iii)
                    and (iv) above, at least ten (10) days prior written notice
                    of the date when the same shall take place (and specifying
                    the date on which the holders of Common Stock shall be
                    entitled to exchange their Common Stock for securities or
                    other property deliverable upon the occurrence of such
                    event).

                          Each such written notice shall be delivered personally
                    or given by first class mail, postage prepaid, addressed to
                    the holders of the Series B Preferred Stock at the address
                    for each such holder as shown on the books and records of
                    the Corporation.

          6.   Voting Rights. The holders of record of shares of Series B
Preferred Stock shall not be entitled to any voting rights except as hereinafter
provided in this Section 6 or as otherwise provided under Sections 242 and 245
of the DGCL.

               (a)  Approval by Series B Preferred Stock. The Corporation shall
          not, without first obtaining the approval of the holders of not less
          than a majority of the total number of shares of the Series B
          Preferred Stock then outstanding voting on an as-converted to Common
          Stock basis:

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                    (i)   amend or repeal any provision of, or add any provision
               to, the Corporation's Certificate of Incorporation or Bylaws if
               such action would materially and adversely affect the rights,
               preferences, privileges, or restrictions of the Series B
               Preferred Stock;

                    (ii)  authorize, create or issue shares of any class or
               series of stock having any preference or priority superior to or
               on a parity with any such preference or priority of the Series B
               Preferred Stock;

                    (iii) amend this paragraph 6(a).

          7.   Redemption.

               (a)  Redemption by the Corporation. As and to the extent
          permitted by law, the Corporation may redeem at its option shares of
          Series B Preferred Stock, at any time in whole or from time to time in
          part, at a redemption price of $1,000.00 per share in cash, together
          with declared and unpaid dividends thereon to the date fixed for
          redemption, without interest.

               (b)  Notice of Redemption; Payment; Surrender of Certificates. In
          the event of the redemption of shares of Series B Preferred Stock
          pursuant to paragraph 7(a), the Corporation shall mail a notice of
          redemption to each holder of record of shares of Series B Preferred
          Stock addressed to the holder at the address of such holder appearing
          on the books of the Corporation or given by the holder to the
          Corporation for the purpose of notice, or, if no such address appears
          or is given, then at the place where the principal executive office of
          the Corporation is located, not earlier than sixty (60) nor later than
          eight (8) days before such payment is due, as set forth above. The
          notice of redemption shall include (i) the date fixed for redemption,
          (ii) the place at which the stockholders may obtain payment of the
          redemption price upon surrender of their share certificates, (iii) the
          amount of the payment due, and (iv) the last date prior to the date of
          redemption that the right of conversion may be exercised. If funds are
          available on the date fixed for the redemption, then whether or not
          the share certificates are surrendered for payment of the redemption
          price, the shares shall no longer be outstanding and the holders
          thereof shall cease to be stockholders of the Corporation with respect
          to the shares redeemed on and after the date fixed for redemption and
          shall be entitled only to receive the redemption price without
          interest upon surrender of the share certificate. If less than all the
          shares represented by one share certificate are to be redeemed, the
          Corporation shall issue a new share certificate for the shares not
          redeemed.

          8.   Waiver of Rights, Preferences or Privileges. Any right,
preference or privilege of the Series B Preferred Stock may be waived and the
provisions of this Certificate of Designation may be amended by the holders of a
majority of the outstanding shares of Series B Preferred Stock and such waiver
shall be binding on all holders of Series B Preferred Stock.

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          9.   General Provisions.

               (a)  The term "Affiliate" as used herein shall have the meaning
          given it in Rule 405 promulgated under the Securities Act of 1933, as
          amended from time to time.

               (b)  The term "Person" as used herein means any corporation,
          limited liability company, partnership, trust, organization,
          association, other entity or individual.

               (c)  The term "outstanding", when used with reference to shares
          of stock, shall mean issued shares, excluding shares held by the
          Corporation or a subsidiary.

               (d)  The headings of the sections, paragraphs, subparagraphs,
          clauses and subclauses of this Certificate of Designations are for
          convenience of reference only and shall not define, limit or affect
          any of the provisions hereof.

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          IN WITNESS WHEREOF, Genaera Corporation has caused this Certificate of
     Designations to be signed and attested by the undersigned this 19th day of
     April 2001.


                                        GENAERA CORPORATION


                                        By: /s/ Christopher P. Schnittker
                                           ------------------------------------
                                           Name:  Christopher P. Schnittker
                                           Title: Vice President and Chief
                                                  Financial Officer

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