EXECUTION COPY 3,750,000 Common Shares TEKMIRA PHARMACEUTICALS CORPORATION (incorporated under the Business Corporations Act ( British Columbia ))

3,750,000 Common Shares

TEKMIRA PHARMACEUTICALS CORPORATION

(incorporated under the Business Corporations Act (British Columbia))

UNDERWRITING AGREEMENT

NICOLAUS & COMPANY, INCORPORATED

As Representative of the several

Underwriters named in Schedule I hereto

One Montgomery Street, Suite 3700

San Francisco, California

Ladies and Gentlemen:

Pharmaceuticals Corporation, a company incorporated under the Business Corporations Act (British Columbia) (the Company ), proposes to sell to the several underwriters (the Underwriters )

named in Schedule I hereto for whom Stifel Nicolaus & Company, Incorporated is acting as representative (the Representative ), an aggregate of 3,750,000 common shares (the Firm

Shares ) of the Company (the Common Shares ). The Company has also granted to the several Underwriters an option to purchase up to an aggregate of 562,500 additional Common Shares, on the terms and for the

purposes set forth in Section 3 hereof (the Option Shares ). The Firm Shares and any Option Shares purchased pursuant to this Underwriting Agreement are herein collectively called the

The Company hereby confirms its agreement with respect to the sale of the Securities to the several

1. Registration Statement and Prospectus. The Company has prepared and filed with the securities regulatory

authorities (the Qualifying Authorities ) in each of the provinces of Canada other than the Province of Qu bec (the Qualifying Jurisdictions ) a preliminary short form base shelf prospectus

dated January 4, 2013 (the Canadian Preliminary Base Prospectus ), and a final short form base shelf prospectus dated January 16, 2013, in respect of an aggregate of up to US$50,000,000 in certain securities of the

Company, including Common Shares (collectively, the Shelf Securities ). The Company has selected the British Columbia Securities Commission (the Reviewing Authority ) as its principal regulator under

the passport system procedures provided for under Multilateral Instrument 11-102 Passport System and National Policy 11-202 Process for

Prospectus Reviews in Multiple Jurisdictions (collectively, the Passport System ) in respect of the offering of the Shelf Securities. The Reviewing Authority has issued a Passport decision document under the Passport

System evidencing that a receipt has been issued (a Passport Decision Document ) on behalf of itself and the other Qualifying Authorities for each of the Canadian Preliminary Base Prospectus and the Canadian Base Prospectus.

The term Canadian Base Prospectus means the final short form base shelf prospectus dated January 16, 2013 relating to the Shelf Securities, including any documents incorporated by reference therein and the documents

otherwise deemed to be a part thereof or included therein pursuant to Canadian Securities Laws (as defined below), at the time the Reviewing Authority issued a Passport Decision Document with respect thereto in accordance with Canadian Securities

Laws, including National

Instrument 44-101 Short Form Prospectus Distributions and National Instrument 44-102

Shelf Distributions (together, the Canadian Shelf Procedures ). The Company has also prepared and filed with the Qualifying Authorities in accordance with the Canadian Shelf Procedures a preliminary prospectus

supplement dated October 16, 2013 relating to the Securities, which excluded certain information (together with the Canadian Base Prospectus, and including any documents incorporated therein by reference and the documents otherwise deemed to be

a part thereof or included therein pursuant to Canadian Securities Laws, the Canadian Preliminary Prospectus ).

The Company has also prepared and filed with the United States Securities and Exchange Commission (the Commission ) a

registration statement on Form F-10 (File No. 333-185883) covering the registration of the Shelf Securities under the United States Securities Act of 1933, as amended (the Securities

Act or Act ) and the rules and regulations (the Rules and Regulations ) of the Commission thereunder, and such amendments to such registration statement as may have been permitted or

required to the date of this Agreement. Such registration statement, including the Canadian Base Prospectus (with such deletions therefrom and additions thereto as are permitted or required by Form F-10

and the Rules and Regulations) and including exhibits to such registration statement has become effective in such form pursuant to Rule 467(b) under the Securities Act. Such registration statement, at any given time, including amendments

thereto to such time, the exhibits and any schedules thereto at such time and the documents incorporated by reference therein pursuant to Item 4 of Form F-10 under the Securities Act at such time, is herein called the

Registration Statement. The Registration Statement at the time it originally became effective is herein called the Original Registration Statement. Any registration statement filed by the Company

pursuant to General Instruction II.E of Form F-10 under the Securities Act is called the Upsizing Registration Statement and, from and after the date and time of filing of the Upsizing Registration Statement, the term

Registration Statement shall include the Upsizing Registration Statement. The prospectus in the form in which it appeared in the Original Registration Statement is herein called the U.S. Base

Prospectus. The preliminary prospectus supplement dated October 16, 2013 relating to the offering of the Securities, including all documents incorporated therein by reference, filed with the Commission pursuant to General

Instruction II.L of Form F-10 under the Securities Act, together with the U.S. Base Prospectus, is hereinafter called a U.S. Preliminary Prospectus.

In addition, the Company (i) shall prepare and file with the Qualifying Authorities in accordance with Section 4(a) hereof a

final prospectus supplement (the Canadian Final Prospectus Supplement ) to the Canadian Base Prospectus relating to the Securities, which includes the information omitted from the Canadian Preliminary Prospectus (together

with the Canadian Base Prospectus, and including any documents incorporated therein by reference and the documents otherwise deemed to be a part thereof or included therein pursuant to Canadian Securities Laws, the Canadian Final

Prospectus ), and (ii) shall prepare and file with the Commission pursuant to General Instruction II.L of Form F-10 and in accordance with Section 4(a) hereof a final

prospectus supplement (the U.S. Final Prospectus Supplement ) to the U.S. Base Prospectus relating to the offering of the Securities (including all documents incorporated therein by reference, together with the

U.S. Base Prospectus, the U.S. Final Prospectus ). The U.S. Preliminary Prospectus and the Canadian Preliminary Prospectus are referred to herein as the Preliminary Prospectuses, and the U.S. Final

Prospectus and the Canadian Final Prospectus are referred to herein as the Final Prospectuses. Any amendment to the Canadian Final Prospectus, any amended or supplemental prospectus, any management information circular,

financial statement, management s discussion and analysis, annual information form, business acquisition report or material change report that may be filed by or on behalf of the Company under the securities laws of the Qualifying Jurisdictions

prior to the expiry of the period of distribution of the Securities, where such document is deemed to be incorporated by reference into the Canadian Final Prospectus, is referred to herein collectively as the Supplementary

Material. Any reference herein to any amendment or supplement to the U.S. Preliminary Prospectus or the U.S. Final Prospectus shall be deemed to refer to

and include (i) the filing of any document with the Reviewing Authority or the Commission after the date of the U.S. Preliminary Prospectus or the U.S. Final Prospectus, as the case may be,

and prior to the First Closing Date or the Second Closing Date, as applicable, which is incorporated therein by reference or is otherwise deemed to be a part thereof or included therein by the Rules and Regulations and (ii) any such document so

filed prior to the First Closing Date or the Second Closing Date, as applicable.

The Underwriters shall offer the Securities for sale to

the public directly and through other investment dealers and brokers in the Qualifying Jurisdictions and the United States only as permitted by applicable law and upon the terms and conditions set forth in the Preliminary Prospectuses and this

Agreement. Notwithstanding the foregoing, the Underwriters represent and warrant that the Underwriters have a reasonable expectation that Securities offered for sale to the public will be sold primarily in the United States of America. The

Underwriters agree that they will not, directly or indirectly, distribute the Registration Statement, the Preliminary Prospectuses or the Final Prospectuses or publish any prospectus, circular, advertisement or other offering material in any

jurisdiction other than the Qualifying Jurisdictions or such states of the United States in which the Securities are duly qualified under U.S. federal and applicable U.S. state securities laws, in such manner as to require registration of the

Securities or the filing of a prospectus or any similar document with respect to the Securities by the Company therein or subject the Company to ongoing periodic reporting obligations in such jurisdiction pursuant to the securities laws of such

jurisdiction. Sales of Securities in the Qualifying Jurisdictions may be made only by or through a dealer appropriately registered under applicable Canadian Securities Laws or in circumstances where an exemption from the Canadian registered dealer

requirements is available, or such requirements do not apply.

The Company has also prepared and filed with the Commission an appointment

of agent for service of process upon the Company on Form F-X in conjunction with the filing of the Registration Statement (the

For purposes of this Agreement, all references to the

Registration Statement, any Upsizing Registration Statement, the U.S. Base Prospectus or the U.S. Preliminary Prospectus, any Issuer Free Writing Prospectus (as defined below) or the U.S. Final Prospectus, or any amendment or supplement to any of

the foregoing, shall be deemed to include the copy filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System ( EDGAR ). For purposes of this Agreement, all references to the Canadian

Preliminary Base Prospectus, the Canadian Base Prospectus, the Canadian Preliminary Prospectus or the Canadian Final Prospectus, or any amendment or supplement to any of the foregoing (including any Supplementary Material), shall include the copy

filed with the Qualifying Authorities pursuant to the System for Electronic Document Analysis and Retrieval ( SEDAR ).

All references in this Agreement to financial statements and schedules and other information which is contained,

included or stated in the Registration Statement, any Upsizing Registration Statement, the U.S. Base Prospectus, the U.S. Preliminary Prospectus or the U.S. Final Prospectus (or other references of like import) shall be

deemed to mean and include all such financial statements and schedules and other information which is incorporated by reference in or otherwise deemed by the Rules and Regulations to be a part of or included in the Registration Statement, any

Upsizing Registration Statement, the U.S. Base Prospectus, the U.S. Preliminary Prospectus or the U.S. Final Prospectus, as the case may be; and all references in this Agreement to amendments or supplements to the Registration Statement, the U.S.

Base Prospectus, the U.S. Preliminary Prospectus or the U.S. Final Prospectus shall be deemed to mean and include the filing of any document under the United States Securities Exchange Act of 1934, as amended (the Exchange

Act ), which is incorporated by reference in or otherwise deemed by Rules and Regulations to be a part of or included in the Registration Statement, the U.S. Base Prospectus, the U.S. Preliminary Prospectus or the U.S. Final Prospectus,

as the case may be. All references in this Agreement to financial statements and other information which is contained,

included or stated in the Canadian Preliminary Base Prospectus, the Canadian Base Prospectus, the Canadian Preliminary Prospectus or the Canadian Final Prospectus (or

other references of like import) shall be deemed to mean and include all such financial statements and other information which is incorporated by reference in or otherwise deemed by Canadian Securities Laws to be a part of or included in the

Canadian Preliminary Base Prospectus, the Canadian Base Prospectus, the Canadian Preliminary Prospectus or the Canadian Final Prospectus, as the case may be.

2. Representations and Warranties of the Company. The Company represents and warrants to, and agrees with, the several

Underwriters as follows:

(a) The Company is a reporting issuer (or equivalent thereof) in each Qualifying Jurisdiction, is not in default

under the securities laws of any Qualifying Jurisdiction, and is in compliance in all material respects with its timely disclosure obligations under the Exchange Act, the Canadian Securities Laws and the requirements of the Toronto Stock Exchange

(the TSX ) and the Nasdaq Global Market ( NASDAQ ). The Company meets the general eligibility requirements for use of the Canadian Shelf Procedures and for the use of a short form base shelf

prospectus with respect to a distribution of securities. The Company meets the general eligibility requirements for use of Form F-10 under the Securities Act. The Reviewing Authority has issued a Passport Decision Document on behalf of itself and

the other Qualifying Authorities for each of the Canadian Preliminary Base Prospectus and the Canadian Base Prospectus; subsequent to the issuance of the Passport Decision Document for the Canadian Base Prospectus, no other document with respect to

the Canadian Base Prospectus has heretofore been filed or transmitted for filing with the Qualifying Authorities, except for any document filed with the Qualifying Authorities subsequent to the date of such Passport Decision Document in the form

heretofore delivered to the Representative.

(b) The Statutory Prospectus (as defined below) at the Time of Sale (as defined below)

complies with the requirements of the Securities Act and the Rules and Regulations in all material respects and does not 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 the light of the circumstances under which they were made, not misleading.

(c) The Original Registration

Statement initially became effective under the Securities Act on January 17, 2013 and any Upsizing Registration Statement has become effective or will become effective upon filing with the Commission. No stop order suspending the effectiveness

of the Registration Statement is in effect and no proceedings for such purpose have been instituted or are pending or, to the best knowledge of the Company, are contemplated or threatened by the Commission. No order, ruling or determination having

the effect of suspending the sale or ceasing the trading of any securities of the Company (including the Securities) has been issued or made by any Qualifying Authority, any other securities commission, stock exchange or other regulatory authority

and no proceedings for that purpose have been instituted or are pending or, to the Company s knowledge, are contemplated by any such authority. Any request on the part of the Commission, any Qualifying Authority or any other securities

commission, stock exchange or other regulatory authority for additional information in connection with the offering contemplated hereby has been complied with.

(d) Each part of the Registration Statement, any Upsizing Registration Statement and any post-effective amendment thereto, at the time such

part became effective, at all other subsequent times until the expiration of the Prospectus Delivery Period (as defined below), and at the First Closing Date and the Second Closing Date (as defined below), as the case may be, and the U.S. Final

Prospectus (or any amendment or supplement to the U.S. Final Prospectus), at the time it is first filed in accordance with General Instruction II.L of Form F-10 or the time of first use within the meaning of the Rules and Regulations, at all

subsequent times until expiration of the Prospectus Delivery Period, and at the First