Exhibit
4.1


 


THIRD
AMENDMENT TO AMENDED AND RESTATED RIGHTS AGREEMENT


 


THIS THIRD
AMENDMENT TO THE AMENDED AND RESTATED RIGHTS AGREEMENT  (this “Amendment”), effective as
of May 27, 2008, between Sonus Pharmaceuticals, Inc., a Delaware
corporation (the “Company”), and Computershare Trust Company, N.A., as Rights Agent (the “Rights
Agent”), amends that certain Amended and Restated Rights Agreement, dated
as of July 24, 2002, by and between Sonus and U.S. Stock Transfer
Corporation, as predecessor Rights Agent, as amended by the First Amendment to
Amended and Restated Rights Agreement, dated October 17, 2005, and the
Second Amendment to Amended and Restated Rights Agreement, dated August 10,
2006 (as amended, the “Rights Agreement”).  Capitalized terms used herein without
definition shall have the meanings given to them in the Rights Agreement.


 


WHEREAS, the
Company is entering into an Arrangement Agreement (as the same may be amended
from time to time, the “Arrangement Agreement”) by and between the
Company and OncoGenex Technologies Inc., a corporation existing under the
federal laws of Canada (“OncoGenex”), pursuant to which the Company and
OncoGenex will effect an arrangement under Section 192 of the Canada
Business Corporations Act (the “Arrangement”);


 


WHEREAS, subject
to the terms of the Arrangement Agreement, each common share and preferred
share of OncoGenex outstanding immediately prior to the closing of the
Arrangement (other than dissenting shares) will be transferred by the holder
thereof, without any act or formality on its part, to the Company in exchange
for that number of fully paid and non-assessable shares of Company common
stock, par value $0.001 per share (the “Company Common Stock”), equal to
the Share Exchange Ratio (as defined in the Arrangement Agreement);


 


WHEREAS, subject
to the terms of the Arrangement Agreement, each debenture of OncoGenex
outstanding immediately prior to the closing of the Arrangement (unless the
holder thereof is a dissenting securityholder) will be transferred by the holder
thereof, without any act or formality on its part, to the Company in exchange
for that number of fully paid and non-assessable shares of Company Common Stock
set forth in the Arrangement Agreement;


 


WHEREAS, the
Company desires to amend the Rights Agreement in connection with the execution
and delivery of the Arrangement Agreement;


 


WHEREAS, the
Board of Directors of the Company has determined that it is in the best
interests of the stockholders of the Company that the Rights Agreement be
amended as set forth below, approved this Amendment and authorized its
appropriate officers to execute and deliver the same to the Rights Agent;


 


WHEREAS, pursuant to Section 27 of the Rights
Agreement, the Company and the Rights Agent may from time to time supplement or
amend the Rights Agreement in accordance with the provisions of Section 27
thereof and the Company desires and directs the Rights Agent to so amend the
Rights Agreement; and


 


WHEREAS, the
Distribution Date has not yet occurred.


 

















 


NOW, THEREFORE,
in accordance with the procedures for amendment of the Rights Agreement set
forth in Section 27 thereof, and in consideration of the foregoing and the
mutual agreements herein set forth, the parties hereby agree as follows:


 


1.                                      The
definition of “Acquiring Person” set forth in Section 1(a) of the
Rights Agreement shall be restated in its entirety to read as follows:


 


“(a) “Acquiring Person” shall mean any
Person who or which, together with all Affiliates and Associates of such
Person, shall be the Beneficial Owner of 15% or more of the shares of Common
Stock of the Company then outstanding, but shall not include (i) the
Company, any Subsidiary of the Company, any employee benefit plan of the
Company or any Subsidiary of the Company, or any Person or entity holding
shares of Common Stock of the Company for or pursuant to the terms of any such
plan, (ii) subject to the limitations set forth in the proviso in this
subsection (a)(ii), Schering AG, its Affiliates or Associates; provided, however, notwithstanding the foregoing, Schering
AG, its Affiliates and Associates shall be an “Acquiring Person” if Schering
AG, its Affiliates and Associates shall be the Beneficial Owner of more than
16% of the shares of Common Stock of the Company then outstanding, or (iii) OncoGenex
Technologies Inc., a corporation existing under the federal laws of Canada (“OncoGenex”),
or any Affiliate, Associate, securityholder or group of securityholders
thereof, who, notwithstanding anything in this Rights Agreement to the
contrary, shall not be deemed to be an “Acquiring Person” as a result of (A) the
approval, execution or delivery of that certain Arrangement Agreement, dated as
of May 27, 2008, by and between the Company and OncoGenex (as the same may
be amended from time to time, the “Arrangement Agreement”), including the
approval, execution and delivery of any amendments thereto; (B) the
approval, execution or delivery of any of the exhibits or schedules to the
Arrangement Agreement; (C) the consummation of the Arrangement (as such
term is defined in the Arrangement Agreement); (D) the acceptance for
payment, issuance, purchase or exchange, of Common Stock pursuant to the
Arrangement Agreement; (E) the announcement of the Arrangement Agreement
or the Arrangement (as such term is defined in the Arrangement Agreement); or (F) the
consummation of any other transaction contemplated by the Arrangement Agreement
or any exhibit or schedule thereto. 
Notwithstanding anything else to the contrary contained herein, no
Person shall become an “Acquiring Person” as the result of an acquisition of
shares of Common Stock by the Company which, by reducing the number of shares
of Common Stock of the Company outstanding, increases the proportionate number
of shares of Common Stock of the Company beneficially owned by such Person to
15% or more of the shares of Common Stock of the Company then outstanding (or
the Beneficial Owner of more than 16% of the shares of Common Stock of the
Company then outstanding in the case of Schering AG, its Affiliates and Associates);
provided, however, that, if a Person
shall become the Beneficial Owner of 15% or more of the shares of Common Stock
of the Company then outstanding (or the Beneficial Owner of more than 16% of
the shares of Common Stock of the Company then outstanding in the case of
Schering AG, its Affiliates and Associates) by reason of share purchases by the
Company and shall, after 


 


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such share purchases by the Company, become the
Beneficial Owner of any additional shares of Common Stock of the Company, then
such Person shall be deemed to be an “Acquiring Person.”  Notwithstanding the foregoing, if the Board
of Directors of the Company determines in good faith that a Person who would
otherwise be an “Acquiring Person,” as defined pursuant to the foregoing
provisions of this paragraph (a), has become such inadvertently, and such
Person divests as promptly as practicable a sufficient number of shares of
Common Stock so that such Person would no longer be an “Acquiring Person,” as
defined pursuant to the foregoing provisions of this paragraph (a), then such
Person shall not be deemed to be an “Acquiring Person” for any purposes of this
Agreement.”


 


2.                                      Section 1(o) of
the Rights Agreement is hereby amended by adding as the final sentence thereto
the following:


 


“Notwithstanding
anything in this Agreement to the contrary, no Stock Acquisition Date shall be
deemed to have occurred solely as a result of (i) the approval, execution
or delivery of the Arrangement Agreement, including the approval, execution and
delivery of any amendments thereto; (ii) the approval, execution or
delivery of any of the exhibits or schedules to the Arrangement Agreement; (iii) the
consummation of the Arrangement (as such term is defined in the Arrangement
Agreement); (iv) the acceptance for payment, issuance, purchase or
exchange, of Common Stock pursuant to the Arrangement Agreement; (v) the
announcement of the Arrangement Agreement or the Arrangement (as such term is
defined in the Arrangement Agreement); or (vi) the consummation of any
other transaction contemplated by the Arrangement Agreement or any exhibit or
schedule thereto.”


 


3.                                      Section 3(a) of
the Rights Agreement is hereby amended by adding as the final sentence thereto
the following:


 


“Notwithstanding anything in this Agreement to the
contrary, no Distribution Date shall be deemed to have occurred solely as a
result of (i) the approval, execution or delivery of the Arrangement
Agreement, including the approval, execution and delivery of any amendments
thereto; (ii) the approval, execution or delivery of any of the exhibits
or schedules to the Arrangement Agreement; (iii) the consummation of the
Arrangement (as such term is defined in the Arrangement Agreement); (iv) the
acceptance for payment, issuance, purchase or exchange, of Common Stock
pursuant to the Arrangement Agreement; (v) the announcement of the
Arrangement Agreement or the Arrangement (as such term is defined in the
Arrangement Agreement); or (vi) the consummation of any other transaction
contemplated by the Arrangement Agreement or any exhibit or schedule thereto.”


 


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4.                                      Section 11(a)(ii) of
the Rights Agreement is hereby amended by adding as the final sentence thereto
the following:


 


“Notwithstanding
the foregoing, no Triggering Event shall be deemed to have occurred as a result
of (i) the approval, execution or delivery of the Arrangement Agreement,
including the approval, execution and delivery of any amendments thereto; (ii) the
approval, execution or delivery of any of the exhibits or schedules to the
Arrangement Agreement; (iii) the consummation of the Arrangement (as such
term is defined in the Arrangement Agreement); (iv) the acceptance for
payment, issuance, purchase or exchange, of Common Stock pursuant to the
Arrangement Agreement; (v) the announcement of the Arrangement Agreement
or the Arrangement (as such term is defined in the Arrangement Agreement); or (vi) the
consummation of any other transaction contemplated by the Arrangement Agreement
or any exhibit or schedule thereto.”


 


5.                                      Section 13(a) of the Rights Agreement
is hereby amended by adding as the final sentence thereto as the following:


 


“Notwithstanding anything
in this Agreement to the contrary, none of the events described in
clauses (x) through (z) of the first sentence of Section 13(a) shall
be deemed to have occurred as a result of (i) the approval, execution or
delivery of the Arrangement Agreement, including the approval, execution and
delivery of any amendments thereto; (ii) the approval, execution or
delivery of any of the exhibits or schedules to the Arrangement Agreement; (iii) the
consummation of the Arrangement (as such term is defined in the Arrangement
Agreement); (iv) the acceptance for payment, issuance, purchase or
exchange, of Common Stock pursuant to the Arrangement Agreement; (v) the
announcement of the Arrangement Agreement or the Arrangement (as such term is
defined in the Arrangement Agreement); or (vi) the consummation of any
other transaction contemplated by the Arrangement Agreement or any exhibit or
schedule thereto.”


 


6.                                      This
Amendment shall become effective upon execution of the Arrangement Agreement by
the Company and OncoGenex.  In the event
that the Arrangement Agreement is terminated by the Company or OncoGenex in
accordance with its terms, the provisions of paragraphs 1 through 5 of this
Amendment shall be deemed repealed and deleted without any further action on
the part of the Company or the Rights Agent.


 


7.                                      Except
as expressly amended hereby, the Rights Agreement remains in full force and
effect in accordance with its terms.


 


8.                                      This
Amendment to the Rights Agreement shall be governed by and construed in
accordance with the laws of the State of Delaware.


 


9.                                      This
Amendment may be executed in any number of counterparts and each of such
counterparts shall for all purposes be deemed an original, and all such
counterparts shall together constitute but one and the same instrument.


 


10.                               Except
as expressly set forth herein, this Amendment shall not by implication or
otherwise alter, modify, amend or in any way affect any of the terms,
conditions, obligations, 


 


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covenants or agreements
contained in the Rights Agreement, all of which are ratified and affirmed in
all respects and shall continue in full force and effect.


 


11.                               The Company hereby certifies to the Rights Agent
that this Amendment is in compliance with Section 27 of the Rights
Agreement.


 


[SIGNATURE PAGE
FOLLOWS]


 


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IN WITNESS WHEREOF, the
parties hereto have caused this Third Amendment to Amended and Restated Rights
Agreement to be duly executed as of the day and year first above written.


 


	
   

  	
  SONUS PHARMACEUTICALS, INC.

  a Delaware corporation

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Michael A. Martino

  
	
   

  	
   

  	
  Michael A. Martino

  
	
   

  	
   

  	
  President and Chief Executive Officer

  
	
   

  	
   

  
	
   

  	
  COMPUTERSHARE TRUST
  COMPANY, N.A.

  as Rights Agent

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Kellie Gwinn

  
	
   

  	
   

  	
  Kellie Gwinn

  
	
   

  	
   

  	
  Vice President