**REGISTRATION
      RIGHTS AGREEMENT**





This
      Registration Rights Agreement (this “ Agreement ”)
      is
      made and entered into as of November 2, 2007, among Lev Pharmaceuticals, Inc.,
      a
      Delaware corporation (the “ Company ”),
      and
      the several lenders signatory hereto (each such lender is a “ Lender ”
and
      collectively, the “ Lenders ”).





This
      Agreement is made pursuant to the Term Loan Agreement, dated as of the date
      hereof among the Company, Mast Capital Management LLC, and each Lender (the
      “ Term
      Loan Agreement ”).





The
      Company and each Lender hereby agrees as follows:





1.  Definitions .
      Capitalized terms used and not otherwise defined herein that are defined in
      the
      Term Loan Agreement shall have the meanings given such terms in the Term Loan
      Agreement. As used in this Agreement, the following terms shall have the
      following meanings:





“ Business
      Day ”
means
      any day except Saturday, Sunday, any day which shall be a federal legal holiday
      in the United States or any day on which banking institutions in the State
      of
      New York are authorized or required by law or other governmental action to
      close.




“ Commission ”
shall
      mean the U.S. Securities and Exchange Commission.




“ Effectiveness
      Period ”
shall
      have the meaning set forth in Section 2(a).




“ Event ”
shall
      have the meaning set forth in Section 2(b).




“ Event
      Date ”
shall
      have the meaning set forth in Section 2(b).




“ Holder ”
or
      “ Holders ”
means
      the holder or holders, as the case may be, from time to time of Registrable
      Securities.




“ Indemnified
      Party ”
shall
      have the meaning set forth in Section 5(c).




“ Indemnifying
      Party ”
shall
      have the meaning set forth in Section 5(c).




“ Proceeding ”
means
      an action, claim, suit, investigation or proceeding (including, without
      limitation, an investigation or partial proceeding, such as a deposition),
      whether commenced or threatened.




“ Prospectus ”
means
      the prospectus included in a Registration Statement (including, without
      limitation, a prospectus that includes any information previously omitted from
      a
      prospectus filed as part of an effective registration statement in reliance
      upon
      Rule 430A promulgated under the Securities Act), as amended or supplemented
      by
      any prospectus supplement, with respect to the terms of the offering of any
      portion of the Registrable Securities covered by a Registration Statement,
      and
      all other amendments and supplements to the Prospectus, including post-effective
      amendments, and all material incorporated by reference or deemed to be
      incorporated by reference in such Prospectus.




“ Registrable
      Securities ”
means
      all of (i) shares of Common Stock issuable upon exercise of the Warrants issued
      by the Company to the Lenders pursuant to the Term Loan Agreement, and (ii)
      any
      shares of Common Stock issued or issuable upon any stock split, dividend or
      other distribution, recapitalization or similar event with respect to the
      foregoing.









“ Registration
      Statement ”
means
      the registration statements required to be filed hereunder, including the
      Prospectus, amendments and supplements to such registration statement or
      Prospectus, including pre- and post-effective amendments, all exhibits thereto,
      and all material incorporated by reference or deemed to be incorporated by
      reference in such registration statement.




“ Rule
      415 ”
means
      Rule 415 promulgated by the Commission pursuant to the Securities Act, as such
      Rule may be amended from time to time, or any similar rule or regulation
      hereafter adopted by the Commission having substantially the same purpose and
      effect as such Rule.




“ Rule
      424 ”
means
      Rule 424 promulgated by the Commission pursuant to the Securities Act, as such
      Rule may be amended from time to time, or any similar rule or regulation
      hereafter adopted by the Commission having substantially the same purpose and
      effect as such Rule.




“ Selling
      Shareholder Questionnaire ”
shall
      have the meaning set forth in Section 3(a).




“ Warrants ”
means
      the common stock purchase warrants to be issued by the Company to the Lenders
      pursuant to the Term Loan Agreement.




2.  Registration Rights .




(a)  Demand
      Right .
      For a period of twelve (12) months following the Closing, one or more Lenders
      holding, in the aggregate, at least fifty percent (50%) of the Registrable
      Securities then held by all Lenders, may request, on one occasion, registration
      for sale under the Securities Act of 1933, as amended (the “ Securities
      Act ”)
      of all or part of the Registrable Securities then held by them, and upon such
      request the Company will promptly take the actions specified in Section 2(a)
      of
      this Agreement.




(i)  Demand
      Procedures .
      Within
      ten (10) Business Days after receipt by the Company of a written registration
      request under Section 2(a) **** (which
      request shall specify the number of shares proposed to be registered and sold
      and the manner in which such sale is proposed to be effected), the Company
      shall
      promptly give written notice to all other Holders of the proposed demand
      registration, and such other Holders shall have the right to join in the
      proposed registration and sale, upon written request to the Company (which
      request shall specify the number of shares proposed to be registered and sold)
      within ten (10) Business Days after receipt of such notice from the
      Company. The Company shall thereafter, as promptly as practicable, use
      commercially reasonable efforts to (i) file with the Commission under the
      Securities Act a Registration Statement on the appropriate form concerning
      all
      Registrable Securities specified in the demand request and all Registrable
      Securities with respect to which the Company has received the written request
      from the other Holders, (ii) cause the Registration Statement to be
      declared effective, and (iii) keep such Registration Statement continuously
      effective under the Securities Act until the first to occur of (A) all
      Registrable Securities covered by such Registration Statement have been sold,
      or
      (B) the date that is two years from the date the Registration Statement was
      declared effective by the Commission (the “ Effectiveness
      Period ”).
      The
      Company shall promptly notify the Holders via facsimile or e-mail of the
      effectiveness of a Registration Statement.









(ii) Delay
      by Company . The
      Company shall not be required to effect a demand registration under the
      Securities Act pursuant to Section
      2(a) **** above
      if (i) the Company receives a request for registration under Section
      2(a) **** less
      than 90 days preceding the anticipated effective date of a proposed underwritten
      public offering of securities of the Company approved by the Company’s Board of
      Directors prior to the Company’s receipt of the request and in such event the
      Company shall not be required to effect any such requested registration until
      120 days after the effective date of such proposed underwritten public offering;
      (ii) within 120 days prior to any such request for registration, a
      registration of securities of the Company has been effected in which the Holders
      had the right to participate pursuant to this Agreement; or (iii) the Board
      of Directors of the Company reasonably determines in good faith that effecting
      such a demand registration at such time would have a material adverse effect
      upon a proposed sale of all (or substantially all) of the assets of the Company,
      or a merger, reorganization, recapitalization, or business combination
      materially affecting the capital structure or equity ownership of the Company,
      or would otherwise be detrimental to the Company because the Company was then
      in
      the process of raising capital in the public or private markets; provided,
      however, that the Company may only delay a demand registration pursuant to
      this
      provision for a period not exceeding 120 days (or until such earlier time as
      such transaction is consummated or no longer proposed). The Company shall
      promptly notify in writing the Holders requesting registration of any decision
      not to effect any such request for registration pursuant to this Section, which
      notice shall set forth in reasonable detail the reason for such decision and
      shall include an undertaking by the Company promptly to notify such Holders
      as
      soon as a demand registration may be effected, and such Holders will hold the
      information in confidence.





(iii)  Reduction .
      If a
      demand registration initiated by any Holders pursuant to Section
      2(a) **** is
      an
      underwritten registration and the managing underwriters advise the Company
      and
      the Holders participating in the demand registration in writing that in their
      opinion the number of shares of Common Stock requested to be included in such
      registration exceeds the number which can be sold in such offering, then the
      amount of such shares that may be included in such registration shall be
      allocated pro rata among the Holders participating in the demand registration
      based on the number of shares of Registrable Securities held on a fully diluted
      basis with all other Holders of Registrable Securities.




(iv)  Withdrawal .
      Holders
      participating in any demand registration pursuant to this Section
      2(a) **** may
      withdraw at any time before a registration statement is declared effective,
      and
      the Company may withdraw such registration statement if no Registrable
      Securities are then proposed to be included (and if withdrawn by the Company
      the
      Holders shall not be deemed to have requested a demand registration for purposes
      of Section 2(a) **** hereof).
      If the Company withdraws a registration statement hereunder in respect of a
      registration for which the Company would otherwise be required to pay expenses
      under this Agreement, the Holders that shall have withdrawn shall reimburse
      the
      Company for all expenses of such registration in proportion to the number of
      shares each such withdrawing Holder shall have requested to be
      registered.





(b)  Piggyback Registration Rights . If
      at any
      time during the Effectiveness Period there is not an effective Registration
      Statement covering all of the Registrable Securities and the Company shall
      determine to prepare and file with the Commission a registration statement
      relating to an offering for its own account or the account of others under
      the
      Securities Act of any of its equity securities, other than a registration
      statement (i) filed pursuant to Section 2(a) of this Agreement or (b) on Form
      S-4 or Form S-8 (each as promulgated under the Securities Act) or their then
      equivalents relating to equity securities to be issued solely in connection
      with
      any acquisition of any entity or business or equity securities issuable in
      connection with the stock option or other employee benefit plans, then the
      Company shall send to each Holder a written notice of such determination and,
      if
      within fifteen days after the date of such notice, any such Holder shall so
      request in writing, the Company shall include in such registration statement
      all
      or any part of such Registrable Securities such Holder requests to be
      registered, subject to customary underwriter cutbacks applicable to all holders
      of registration rights on a pro rata basis, *provided* that if
      at any time after giving written notice of its intention to register any
      securities and prior to the effective date of the registration statement filed
      in connection with such registration, the Company shall determine for any reason
      not to register or to delay registration of such securities, the Company may,
      at
      its election, give written notice of such determination to such Holder and,
      thereupon, (i) in the case of a determination not to register, shall be relieved
      of its obligation to register any Registrable Securities in connection with
      such
      registration (but not from its obligation to pay expenses in accordance with
      Section 4 hereof), and (ii) in the case of a determination to delay registering,
      shall be permitted to delay registering any Registrable Securities being
      registered pursuant to this Section 2(b) for the same period as the delay in
      registering such other securities Notwithstanding the foregoing, the Company
      shall not be required to register any Registrable Securities pursuant to this
      Section 2(b) that are eligible for resale pursuant to Rule 144(k) promulgated
      under the Securities Act or that are the subject of a then effective
      Registration Statement. Notwithstanding the foregoing, nothing herein shall
      be
      construed of relieving the Company of its obligations under this
      Agreement.









(c)  Exceptions .
      The Company shall have no obligation to include shares of Common Stock owned
      by
      any Holder in a registration statement pursuant to this Section 1.2, unless
      and until such Holder (a) in connection with any underwritten offering,
      agrees to enter into an underwriting agreement, a custody agreement and power
      of
      attorney and any other customary documents required in an underwritten offering
      all in customary form and containing customary provisions and (b) shall
      have furnished the Company with all information and statements about or
      pertaining to such Holder in such reasonable detail and on such timely basis
      as
      is reasonably deemed by the Company to be legally required with respect to
      the
      preparation of the registration statement.


3.  Registration
      Procedures




In
      connection with the Company’s registration obligations hereunder, the Company
      shall:




(a)  Not
      less
      than five Business Days prior to the filing of each Registration Statement
      and
      not less than 1 Business Day prior to the filing of any related Prospectus
      or
      any amendment or supplement thereto, (i) furnish to each Holder copies of all
      such documents proposed to be filed, which documents will be subject to the
      review of such Holders (it being acknowledged and agreed that if a Holder does
      not object to or comment on the aforementioned documents within such five
      Business Day period, then the Holder shall be deemed to have consented to and
      approved the use of such documents), and (ii) cause its officers and directors,
      counsel and independent certified public accountants to respond to such
      inquiries as shall be necessary, in the reasonable opinion of respective counsel
      to each Holder to conduct a reasonable investigation within the meaning of
      the
      Securities Act. The Company shall not file a Registration Statement or any
      such
      Prospectus or any amendments or supplements thereto to which the Holders of
      a
      majority of the Registrable Securities shall reasonably object in good faith,
      provided that, the Company is notified of such objection in writing no later
      than 4 Business Days after the Holders have been so furnished copies of a
      Registration Statement or 1 Business Day after the Holders have been so
      furnished copies of any related Prospectus or amendment or supplement thereto.
      Each Holder agrees to furnish to the Company a completed Questionnaire in the
      form attached to this Agreement as Annex A (a “ Selling
      Shareholder Questionnaire ”)
      not
      less than two Business Days prior to date on which the Company files the
      Registration Statement (the “ Filing
      Date ”)
      or by
      the end of the fourth Business Day following the date on which such Holder
      receives draft materials in accordance with this Section. The Company shall
      not
      be required to include the Registrable Securities of a Holder in a Registration
      Statement to any Holder who fails to furnish to the Company a fully completed
      Selling Holder Questionnaire at least two Business Days prior to the Filing
      Date
      (subject to the requirements set forth in Section 3(a)).









(b)  (i)
      Prepare and file with the Commission such amendments, including post-effective
      amendments, to a Registration Statement and the Prospectus used in connection
      therewith as may be necessary to keep a Registration Statement continuously
      effective as to the applicable Registrable Securities for the Effectiveness
      Period and prepare and file with the Commission such additional Registration
      Statements in order to register for resale under the Securities Act all of
      the
      Registrable Securities; (ii) cause the related Prospectus to be amended or
      supplemented by any required Prospectus supplement (subject to the terms of
      this
      Agreement), and as so supplemented or amended to be filed pursuant to Rule
      424;
      (iii) respond as promptly as reasonably possible to any comments received from
      the Commission with respect to a Registration Statement or any amendment thereto
      and as promptly as reasonably possible provide the Holders true and complete
      copies of all correspondence from and to the Commission relating to a
      Registration Statement that pertain to the Holders as Selling Shareholders
      (provided that the Company may excise any information contained therein which
      would constitute material non-public information as to any Holder which has
      not
      executed a confidentiality agreement with the Company); and (iv) comply in
      all
      material respects with the provisions of the Securities Act and the Securities
      Exchange Act of 1934, as amended (the “ Exchange
      Act ”)
      with
      respect to the disposition of all Registrable Securities covered by a
      Registration Statement during the applicable period in accordance (subject
      to
      the terms of this Agreement) with the intended methods of disposition by the
      Holders thereof set forth in such Registration Statement as so amended or in
      such Prospectus as so supplemented.




(c)  Notify
      the Holders of Registrable Securities to be sold (which notice shall, pursuant
      to clauses (iii) through (v) hereof, be accompanied by an instruction to suspend
      the use of the Prospectus until the requisite changes have been made) as
      promptly as reasonably possible (and, in the case of (i)(A) below, not less
      than
      1 Business Day prior to such filing) and (if requested by any such Person)
      confirm such notice in writing no later than one Business Day following the
      day
      (i)(A) when a Prospectus or any Prospectus supplement or post-effective
      amendment to a Registration Statement is proposed to be filed; (B) when the
      Commission notifies the Company whether there will be a “review” of such
      Registration Statement and whenever the Commission comments in writing on such
      Registration Statement; and (C) with respect to a Registration Statement or
      any
      post-effective amendment, when the same has become effective; (ii) of any
      request by the Commission or any other Federal or state governmental authority
      (or the NASD) for amendments or supplements to a Registration Statement or
      Prospectus or for additional information; (iii) of the issuance by the
      Commission or any other federal or state governmental authority of any stop
      order suspending the effectiveness of a Registration Statement covering any
      or
      all of the Registrable Securities or the initiation of any Proceedings for
      that
      purpose; (iv) of the receipt by the Company of any notification with respect
      to
      the suspension of the qualification or exemption from qualification of any
      of
      the Registrable Securities for sale in any jurisdiction, or the initiation
      or
      threatening of any Proceeding for such purpose; and (v) of the occurrence of
      any
      event or passage of time that makes the financial statements included in a
      Registration Statement ineligible for inclusion therein or any statement made
      in
      a Registration Statement or Prospectus or any document incorporated or deemed
      to
      be incorporated therein by reference untrue in any material respect or that
      requires any revisions to a Registration Statement, Prospectus or other
      documents so that, in the case of a Registration Statement or the Prospectus,
      as
      the case may be, it will not contain any untrue statement of a material fact
      or
      omit to state any material fact required to be stated therein or necessary
      to
      make the statements therein, in light of the circumstances under which they
      were
      made, not misleading.




(d)  Use
      its
      commercially reasonable efforts to avoid the issuance of, or, if issued, obtain
      the withdrawal of (i) any order suspending the effectiveness of a Registration
      Statement, or (ii) any suspension of the qualification (or exemption from
      qualification) of any of the Registrable Securities for sale in any
      jurisdiction, at the earliest practicable moment.




(e)  If
      requested by a Holder, furnish to such Holder, without charge, at least one
      conformed copy of each such Registration Statement and each amendment thereto,
      including financial statements and schedules, all documents incorporated or
      deemed to be incorporated therein by reference to the extent requested by such
      Person, and all exhibits to the extent requested by such Person (including
      those
      previously furnished or incorporated by reference) promptly after the filing
      of
      such documents with the Commission.









(f)  Subject
      to the terms of this Agreement, the Company hereby consents to the use of such
      Prospectus and each amendment or supplement thereto by each of the selling
      Holders in connection with the offering and sale of the Registrable Securities
      covered by such Prospectus and any amendment or supplement thereto, except
      after
      the giving of any notice pursuant to Section 3(c), and undertakes to furnish
      to
      such Holders such number of copies of such Prospectus and any amendment or
      supplement thereto as the Holders may reasonably request.




(g)  Prior
      to
      any resale of Registrable Securities by a Holder, use its commercially
      reasonable efforts to register or qualify or cooperate with the selling Holders
      in connection with the registration or qualification (or exemption from the
      registration or qualification) of such Registrable Securities for the resale
      by
      the Holder under the securities or Blue Sky laws of such jurisdictions within
      the United States as any Holder reasonably requests in writing, to keep each
      registration or qualification (or exemption therefrom) effective during the
      Effectiveness Period and to do any and all other acts or things reasonably
      necessary to enable the disposition in such jurisdictions of the Registrable
      Securities covered by each Registration Statement; provided, that the Company
      shall not be required to qualify generally to do business in any jurisdiction
      where it is not then so qualified, subject the Company to any material tax
      in
      any such jurisdiction where it is not then so subject or file a general consent
      to service of process in any such jurisdiction.




(h)  Cooperate
      with the Holders to facilitate the timely preparation and delivery of
      certificates representing Registrable Securities to be delivered to a transferee
      pursuant to a Registration Statement, which certificates shall be free, to
      the
      extent permitted by the Warrant, of all restrictive legends, and to enable
      such
      Registrable Securities to be in such denominations and registered in such names
      as any such Holders may request.




(i)  Upon
      the
      occurrence of any event contemplated by this Section 3, as promptly as
      reasonably possible under the circumstances taking into account the Company’s
      good faith assessment of any adverse consequences to the Company and its
      stockholders of the premature disclosure of such event, prepare a supplement
      or
      amendment, including a post-effective amendment, to a Registration Statement
      or
      a supplement to the related Prospectus or any document incorporated or deemed
      to
      be incorporated therein by reference, and file any other required document
      so
      that, as thereafter delivered, neither a Registration Statement nor such
      Prospectus will contain an untrue statement of a material fact or omit to state
      a material fact required to be stated therein or necessary to make the
      statements therein, in light of the circumstances under which they were made,
      not misleading. If
      the
      Company notifies the Holders in accordance with clauses (iii) through (v) of
      Section 3(c) above to suspend the use of any Prospectus until the requisite
      changes to such Prospectus have been made, then the Holders shall suspend use
      of
      such Prospectus. The Company will use, in good faith, its commercially
      reasonable best efforts to ensure that the use of the Prospectus may be resumed
      as promptly as is practicable.




(j)  Cooperate
      with any reasonable due diligence investigation undertaken by the Holders in
      connection with the sale of Registrable Securities, including, without
      limitation, by making available any documents and information; provided that the
      Company will not deliver or make available to any Holder material, nonpublic
      information unless such Holder specifically requests in advance to receive
      material, nonpublic information in writing and, if requested by the Company,
      such Holder agrees in writing to treat such information
      confidentially.









(k)  Comply
      with all applicable rules and regulations of the Commission.




(l)  The
      Company may require each selling Holder to furnish to the Company a certified
      statement as to the number of shares of Common Stock beneficially owned by
      such
      Holder and, if required by the Commission, the natural persons thereof that
      have
      voting and dispositive control over the Shares.




4.  Registration
      Expenses .
      All
      fees and expenses incident to the performance of or compliance with this
      Agreement by the Company shall be borne by the Company whether or not any
      Registrable Securities are sold pursuant to a Registration Statement. The fees
      and expenses referred to in the foregoing sentence shall include, without
      limitation, (i) all registration and filing fees (including, without limitation,
      fees and expenses (A) with respect to filings required to be made with any
      regulatory authority or trading market on which the Common Stock is then listed
      for trading and (B) in compliance with applicable state securities or Blue
      Sky
      laws reasonably agreed to by the Company in writing (including, without
      limitation, fees and disbursements of counsel for the Company in connection
      with
      Blue Sky qualifications or exemptions of the Registrable Securities), (ii)
      printing expenses (including, without limitation, expenses of printing
      certificates for Registrable Securities, (iii) messenger, telephone and delivery
      expenses, (iv) fees and disbursements of counsel for the Company, (v) Securities
      Act liability insurance, if the Company so desires such insurance, and (vi)
      fees
      and expenses of all other persons retained by the Company in connection with
      the
      consummation of the transactions contemplated by this Agreement. In addition,
      the Company shall be responsible for all of its internal expenses incurred
      in
      connection with the consummation of the transactions contemplated by this
      Agreement (including, without limitation, all salaries and expenses of its
      officers and employees performing legal or accounting duties), the expense
      of
      any annual audit and the fees and expenses incurred in connection with the
      listing of the Registrable Securities on any securities exchange as required
      hereunder. In no event shall the Company be responsible for any broker or
      similar commissions of any Holder or any legal fees or other costs of the
      Holders.




5.  Indemnification




(a)  Indemnification
      by the Company .
      The
      Company shall, notwithstanding any termination of this Agreement, indemnify
      and
      hold harmless each Holder, the officers, directors, members, partners, agents,
      investment advisors and employees (and any other persons with a functionally
      equivalent role of a person holding such titles, notwithstanding a lack of
      such
      title or any other title) of each of them, each person who controls any such
      Holder (within the meaning of Section 15 of the Securities Act or Section 20
      of
      the Exchange Act) and the officers, directors, members, shareholders, partners,
      agents and employees (and any other persons with a functionally equivalent role
      of a person holding such titles, notwithstanding a lack of such title or any
      other title) of each such controlling person, to the fullest extent permitted
      by
      applicable law, from and against any and all losses, claims, damages,
      liabilities, costs (including, without limitation, reasonable attorneys’ fees)
      and expenses (collectively, “ Losses ”),
      as
      incurred, arising out of or relating to (1) any untrue or alleged untrue
      statement of a material fact contained in a Registration Statement, any
      Prospectus or any form of prospectus or in any amendment or supplement thereto
      or in any preliminary prospectus, or arising out of or relating to any omission
      or alleged omission of a material fact required to be stated therein or
      necessary to make the statements therein (in the case of any Prospectus or
      form
      of prospectus or supplement thereto, in light of the circumstances under which
      they were made) not misleading, or (2) any violation or alleged violation by
      the
      Company of the Securities Act, Exchange Act or any state securities law, or
      any
      rule or regulation thereunder, in connection with the performance of its
      obligations under this Agreement, except to the extent, but only to the extent,
      that (i) such untrue statements or omissions are based upon information
      regarding such Holder furnished to the Company in writing by such Holder
      specifically for use therein; or (ii) in the case of an occurrence of an event
      of the type specified in Section 3(c)(iii)-(v), the use by such Holder of an
      outdated or defective Prospectus after the Company has notified such Holder
      in
      writing that the Prospectus is outdated or defective. The Company shall notify
      the Holders promptly of the institution, threat or assertion of any Proceeding
      arising from or in connection with the transactions contemplated by this
      Agreement of which the Company is aware. The Holders agree that the indemnity
      agreement contained in this Section 5(a) shall not apply to amounts paid in
      settlement of any Losses if such settlement is effected without the prior
      written consent of the Company, which consent shall not be unreasonably
      withheld.









(b)  Indemnification
      by Holders .
      Each
      Holder shall, severally and not jointly, indemnify and hold harmless the
      Company, its directors, officers, agents and employees, each person who controls
      the Company (within the meaning of Section 15 of the Securities Act and Section
      20 of the Exchange Act), and the directors, officers, agents or employees of
      such controlling persons, to the fullest extent permitted by applicable law,
      from and against all Losses, as incurred, to the extent arising out of or based
      upon: (x) such Holder’s failure to comply with the prospectus delivery
      requirements of the Securities Act or (y) any untrue or alleged untrue statement
      of a material fact contained in any Registration Statement, any Prospectus,
      or
      any form of prospectus, or in any amendment or supplement thereto or in any
      preliminary prospectus, or arising out of or relating to any omission or alleged
      omission of a material fact required to be stated therein or necessary to make
      the statements therein not misleading (i) to the extent that such untrue
      statement or omission is contained in any information so furnished by such
      Holder to the Company in writing specifically for use therein or (ii) in the
      case of an occurrence of an event of the type specified in Section
      3(c)(iii)-(v), the use by such Holder of an outdated or defective Prospectus
      after the Company has notified such Holder in writing that the Prospectus is
      outdated or defective. The Company agrees that the indemnity agreement contained
      in this Section 5(b) shall not apply to amounts paid in settlement of any Losses
      if such settlement is effected without the prior written consent of the Holder,
      which consent shall not be unreasonably withheld.




(c)  Conduct
      of Indemnification Proceedings .
      If any
      Proceeding shall be brought or asserted against any person entitled to indemnity
      hereunder (an “ Indemnified
      Party ”),
      such
      Indemnified Party shall promptly notify the person from whom indemnity is sought
      (the “ Indemnifying
      Party ”)
      in
      writing, and the Indemnifying Party shall have the right to assume the defense
      thereof, including the employment of counsel reasonably satisfactory to the
      Indemnified Party and the payment of all fees and expenses incurred in
      connection with defense thereof; provided, that the failure of any Indemnified
      Party to give such notice shall not relieve the Indemnifying Party of its
      obligations or liabilities pursuant to this Agreement, except (and only) to
      the
      extent that it shall be finally determined by a court of competent jurisdiction
      (which determination is not subject to appeal or further review) that such
      failure shall have prejudiced the Indemnifying Party.




An
      Indemnified Party shall have the right to employ separate counsel in any such
      Proceeding and to participate in the defense thereof, but the fees and expenses
      of such counsel shall be at the expense of such Indemnified Party or Parties
      unless: (1) the Indemnifying Party has agreed in writing to pay such fees and
      expenses; (2) the Indemnifying Party shall have failed promptly to assume the
      defense of such Proceeding and to employ counsel reasonably satisfactory to
      such
      Indemnified Party in any such Proceeding; or (3) the named parties to any such
      Proceeding (including any impleaded parties) include both such Indemnified
      Party
      and the Indemnifying Party, and counsel to the Indemnified Party shall
      reasonably believe that a material conflict of interest is likely to exist
      if
      the same counsel were to represent such Indemnified Party and the Indemnifying
      Party (in which case, if such Indemnified Party notifies the Indemnifying Party
      in writing that it elects to employ separate counsel at the expense of the
      Indemnifying Party, the Indemnifying Party shall not have the right to assume
      the defense thereof and the reasonable fees and expenses of no more than one
      separate counsel shall be at the expense of the Indemnifying Party). The
      Indemnifying Party shall not be liable for any settlement of any such Proceeding
      effected without its written consent, which consent shall not be unreasonably
      withheld or delayed. No Indemnifying Party shall, without the prior written
      consent of the Indemnified Party, effect any settlement of any pending
      Proceeding in respect of which any Indemnified Party is a party, unless such
      settlement includes an unconditional release of such Indemnified Party from
      all
      liability on claims that are the subject matter of such Proceeding.









Subject
      to the terms of this Agreement, all reasonable fees and expenses of the
      Indemnified Party (including reasonable fees and expenses to the extent incurred
      in connection with investigating or preparing to defend such Proceeding in
      a
      manner not inconsistent with this Section) shall be paid to the Indemnified
      Party, as incurred, within twenty Business Days of written notice thereof to
      the
      Indemnifying Party; provided ,
      that
      the Indemnified Party shall promptly reimburse the Indemnifying Party for that
      portion of such fees and expenses applicable to such actions for which such
      Indemnified Party is judicially determined to be not entitled to indemnification
      hereunder.




(d)  Contribution .
      If the
      indemnification under Section 5(a) or 5(b) is unavailable to an Indemnified
      Party or insufficient to hold an Indemnified Party harmless for any Losses,
      then
      each Indemnifying Party shall contribute to the amount paid or payable by such
      Indemnified Party, in such proportion as is appropriate to reflect the relative
      fault of the Indemnifying Party and Indemnified Party in connection with the
      actions, statements or omissions that resulted in such Losses as well as any
      other relevant equitable considerations. The relative fault of such Indemnifying
      Party and Indemnified Party shall be determined by reference to, among other
      things, whether any action in question, including any untrue or alleged untrue
      statement of a material fact or omission or alleged omission of a material
      fact,
      has been taken or made by, or relates to information supplied by, such
      Indemnifying Party or Indemnified Party, and the parties’ relative intent,
      knowledge, access to information and opportunity to correct or prevent such
      action, statement or omission. The amount paid or payable by a party as a result
      of any Losses shall be deemed to include, subject to the limitations set forth
      in this Agreement, any reasonable attorneys’ or other fees or expenses incurred
      by such party in connection with any Proceeding to the extent such party would
      have been indemnified for such fees or expenses if the indemnification provided
      for in this Section was available to such party in accordance with its
      terms.




The
      parties hereto agree that it would not be just and equitable if contribution
      pursuant to this Section 5(d) were determined by pro rata allocation or by
      any
      other method of allocation that does not take into account the equitable
      considerations referred to in the immediately preceding paragraph.
      Notwithstanding the provisions of this Section 5(d), no Holder shall be required
      to contribute, in the aggregate, any amount in excess of the amount by which
      the
      net proceeds actually received by such Holder from the sale of the Registrable
      Securities subject to the Proceeding exceeds the amount of any damages that
      such
      Holder has otherwise been required to pay by reason of such untrue or alleged
      untrue statement or omission or alleged omission, except in the case of fraud
      by
      such Holder. No person guilty of fraudulent misrepresentation (within the
      meaning of Section 11(f) of the Securities Act) shall be entitled to
      contribution from any Person who was not guilty of such fraudulent
      misrepresentation.




The
      indemnity and contribution agreements contained in this Section are in addition
      to any liability that the Indemnifying Parties may have to the Indemnified
      Parties.




6.  Miscellaneous




(a)  Compliance .
      Each
      Holder covenants and agrees that it will comply with the prospectus delivery
      requirements of the Securities Act as applicable to it in connection with sales
      of Registrable Securities pursuant to a Registration Statement.




(b)  Discontinued
      Disposition .
      Each
      Holder agrees by its acquisition of Registrable Securities that, upon receipt
      of
      a notice from the Company of the occurrence of any event of the kind described
      in Section 3(c)(iii)-(v), such Holder will forthwith discontinue disposition
      of
      such Registrable Securities under a Registration Statement until it is advised
      in writing by the Company that the use of the applicable Prospectus (as it
      may
      have been supplemented or amended) may be resumed. The Company will use its
      commercially reasonable efforts to ensure that the use of the Prospectus may
      be
      resumed as promptly as it practicable.









(c)  Amendments
      and Waivers .
      The
      provisions of this Agreement, including the provisions of this sentence, may
      not
      be amended, modified or supplemented, and waivers or consents to departures
      from
      the provisions hereof may not be given, unless the same shall be in writing
      and
      signed by the Company and the Holders of at least 50% of the then outstanding
      Registrable Securities. Notwithstanding the foregoing, a waiver or consent
      to
      depart from the provisions hereof with respect to a matter that relates
      exclusively to the rights of Holders and that does not directly or indirectly
      affect the rights of other Holders may be given by Holders of all of the
      Registrable Securities to which such waiver or consent relates; provided , however ,
      that
      the provisions of this sentence may not be amended, modified, or supplemented
      except in accordance with the provisions of the immediately preceding
      sentence.




(d)  Notices .
      Any and
      all notices or other communications or deliveries required or permitted to
      be
      provided hereunder shall be delivered as set forth in the Purchase
      Agreement.




(e)  Successors
      and Assigns .
      This
      Agreement shall inure to the benefit of and be binding upon the successors
      and
      permitted assigns of each of the parties and shall inure to the benefit of
      each
      Holder. The Company may not assign its rights (except by merger) or obligations
      hereunder without the prior written consent of all of the Holders of the
      then-outstanding Registrable Securities. Each Holder may assign their respective
      rights hereunder in the manner and to the Persons as permitted under the
      Warrant.




(f)  Execution
      and Counterparts .
      This
      Agreement may be executed in two or more counterparts, all of which when taken
      together shall be considered one and the same agreement and shall become
      effective when counterparts have been signed by each party and delivered to
      the
      other party, it being understood that both parties need not sign the same
      counterpart. In the event that any signature is delivered by facsimile
      transmission or by e-mail delivery of a “.pdf” format data file, such signature
      shall create a valid and binding obligation of the party executing (or on whose
      behalf such signature is executed) with the same force and effect as if such
      facsimile or “.pdf” signature page were an original thereof.




(g)  Governing
      Law .
      All
      questions concerning the construction, validity, enforcement and interpretation
      of this Agreement shall be determined in accordance with the provisions of
      the
      New York law.




(h)  Severability .
      If any
      term, provision, covenant or restriction of this Agreement is held by a court
      of
      competent jurisdiction to be invalid, illegal, void or unenforceable, the
      remainder of the terms, provisions, covenants and restrictions set forth herein
      shall remain in full force and effect and shall in no way be affected, impaired
      or invalidated, and the parties hereto shall use their commercially reasonable
      best efforts to find and employ an alternative means to achieve the same or
      substantially the same result as that contemplated by such term, provision,
      covenant or restriction. It is hereby stipulated and declared to be the
      intention of the parties that they would have executed the remaining terms,
      provisions, covenants and restrictions without including any of such that may
      be
      hereafter declared invalid, illegal, void or unenforceable.




(i)  Headings .
      The
      headings in this Agreement are for convenience only, do not constitute a part
      of
      this Agreement, and shall not be deemed to limit or affect any of the provisions
      hereof.




*************************





IN
      WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
      as
      of the date first written above.




Lev
                Pharmaceuticals, Inc.By:
            /s/ Joshua
              D.
              ScheinName:
              Joshua D. ScheinTitle:
                Chief Executive Officer








[SIGNATURE
      PAGE OF HOLDERS FOLLOWS]





[SIGNATURE
      PAGE OF HOLDERS RRA]





Name
      of
      Holder: Mast Credit Opportunities I Master Fund Limited








*Signature
      of Authorized Signatory of Holder* : /s/
      Christopher B. Madison ____________


Name
      of
      Authorized Signatory: Christopher B. Madison


Title
      of
      Authorized Signatory: Director







**Annex
      A**




**Lev
      Pharmaceuticals, Inc.**




**Selling
      Securityholder Notice and Questionnaire**