EXECUTION COPY



UNDERWRITING
AGREEMENT



March 27, 2014



Lorus Therapeutics Inc.
2 Meridian Road
Toronto, Ontario
M9W 4Z7



| | Attention: | Gregory K. Chow
Chief Financial Officer
| | ---------- | ---------------------------------------



Dear Sir:



RBC Dominion Securities
Inc. (the “Lead Underwriter”), Roth Capital Partners, LLC (“ROTH”) and Cormark Securities Inc. (collectively
with the Lead Underwriter, the “Underwriters”) understand that Lorus Therapeutics Inc. (the “Company”):



| | (i) | proposes to issue and sell an aggregate of 50,000,000 common shares of the Company (the “Offered
Shares”); and
| | --- | --------------------------------------------------------------------------------------------------------------



| | (ii) | has filed a preliminary short form prospectus dated March 26, 2014 (such short form prospectus,
including the documents incorporated by reference therein, the “Initial Preliminary Prospectus”) relating to the distribution
of the Offered Shares and the Over-Allotment Shares (as defined herein) (collectively, the “Offered Securities”) with
the Securities Commissions (as defined herein) and that a Passport Decision Document (as defined herein) was issued on March 26,
2014 in respect of the Initial Preliminary Prospectus by the Ontario Securities Commission (the “Reviewing Authority”),
in its capacity as principal regulator, pursuant to the Passport System (as defined herein) evidencing that a receipt therefor
has been issued by the Securities Commissions.
| | ---- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



Upon and subject to the
terms and conditions hereof: the Underwriters hereby severally offer to purchase from the Company in their respective percentages
set out in paragraph 13 hereof, and the Company hereby agrees to sell to the Underwriters the Offered Shares at a price of
$0.50 per Offered Share (the “Offering Price”), for an aggregate purchase price of $25,000,000 (the “Purchase
Price”).



The Company shall, as soon as possible
after the execution hereof and on a basis acceptable to the Underwriters, acting reasonably, prepare and file under and as required
by Securities Laws with each of the Securities Commissions an amended and restated Initial Preliminary Prospectus (such short form
prospectus, including the documents incorporated by reference therein, the “Amended and Restated Preliminary Prospectus”)
and all other required documents and obtain a Passport Decision Document therefor from the Reviewing Authority no later than 5:00
p.m. (Toronto time) on March 27, 2014. The Company shall also prepare and, forthwith after any comments with respect to the Amended
and Restated Preliminary Prospectus have been received from and have been resolved with the Reviewing Authority, and on a basis
acceptable to the Underwriters, acting reasonably, file under and as required by Securities Laws with each of the Securities Commissions
a (final) short form prospectus (such short form prospectus, including the documents incorporated by reference therein, which includes,
for greater certainty, the template version (as defined herein) of any marketing materials (as defined herein) provided to potential
investors in accordance with paragraph 4 in connection with the distribution of the Offered Securities) (the “Final Prospectus”)
and all other required documents, in order to qualify for distribution to the public the Offered Securities in each of the Qualifying
Jurisdictions through the Underwriters (other than ROTH), and obtain a Passport Decision Document therefor from the Reviewing Authority
no later than the Qualification Deadline (as defined herein).











Offered Securities may
also be offered and sold in the United States by the Underwriters directly or through their U.S. registered broker-dealer affiliates
(the “U.S. Affiliates”), as applicable, pursuant to, and only pursuant to, Rule 144A (as defined herein) and in accordance
with applicable state securities laws and the provisions of Annex A hereto.



The Company hereby grants
to the Underwriters an over-allotment option (the “Over-Allotment Option”) for the purpose of satisfying over-allotments,
if any, and for market stabilization purposes by the Underwriters. The Over-Allotment Option shall entitle the Underwriters to
purchase from the Company up to an additional 7,500,000 common shares of the Company (the “Over-Allotment Shares”)
at a price of $0.50 per Over-Allotment Share. The Over-Allotment Option shall be exercisable in whole or in part, at any time and
from time to time, up to 30 days after the Closing Date (the “Over-Allotment Expiry Date”). Each Underwriter may purchase
their respective percentages, as set out in paragraph 13 hereof, of Over-Allotment Shares in respect of which the Over-Allotment
Option is exercised. If the Lead Underwriter, on behalf of the Underwriters, elects to exercise the Over-Allotment Option, the
Lead Underwriter shall deliver written notice to the Company specifying the number of Over-Allotment Shares in respect of which
the Over-Allotment Option is at such time being exercised.



In consideration of the
Underwriters’ agreement to purchase the Offered Shares which will result from the acceptance of this offer by the Company,
and in consideration of the services to be rendered by the Underwriters in connection with the Offering (as defined herein), the
Company agrees to pay to the Lead Underwriter, on behalf of the Underwriters, at the Closing Time (as defined herein) a cash fee
(the “Underwriting Fee”) of $1,750,000 (being 7.0% of the gross proceeds of the Offered Shares purchased by the Underwriters
at the Closing Time), and the Company agrees to pay to the Lead Underwriter, on behalf of the Underwriters, at the Over-Allotment
Closing Time (as defined herein) the fee set forth in paragraph 8.3, in each case, plus applicable taxes, if any. The Lead
Underwriter shall be entitled to receive, out of the Underwriting Fee, a work fee equal to 6.0% of the aggregate Underwriting Fee
(the “Work Fee”). The allocation of the remainder of the Underwriting Fee (after application of the Work Fee)
among the Underwriters will be in the respective percentages set forth in paragraph 13 hereof.



Terms and Conditions



| | 1. | Definitions and Interpretation
| | -- | ------------------------------



| | 1.1 | Whenever used in this Agreement:
| | --- | --------------------------------



“Agreement” means this
underwriting agreement;



“Amended and Restated Preliminary
Prospectus” has the meaning given to it above;



“Amendment” means the
Amended and Restated Preliminary Prospectus and any other amendment to the Preliminary Prospectus or the Final Prospectus required
to be prepared and filed by the Company under Securities Laws in connection with the Offering;



“Auditors” means KPMG
LLP;



2







“Business Day” means
any day other than a Saturday or a Sunday on which Schedule I Canadian chartered banks are open for business in Toronto, Ontario;



“Claims” means, with
respect to any Indemnified Party, any losses (other than losses of profit in connection with the distribution of the Offered Securities),
claims, costs, expenses, actions, suits, proceedings, investigations, damages and liabilities (joint and several), including, without
limitation, the fees and expenses of such Indemnified Party’s counsel, all amounts paid to settle Claims if settled in accordance
with the terms hereof or satisfy judgments or awards, and other out-of-pocket expenses incurred in investigating and defending
any pending or threatened action, suit, proceeding, investigation or claim that may be made or threatened against any such Indemnified
Party or in enforcing any indemnification provided for hereunder;



“Closing Date” means
April 10, 2014 or any earlier or later date as the Company and the Lead Underwriter, on behalf of the Underwriters, may mutually
agree upon in writing as the date on which the transactions contemplated herein are completed;



“Closing Time” means
8:00 a.m., Toronto time, on the Closing Date, or such other time on the Closing Date as the Company and the Lead Underwriter,
on behalf of the Underwriters, may mutually agree upon;



“Common Shares” means
the common shares of the Company and includes, for certainty, the Offered Securities;



“Company” has the meaning
given to it above;



“Company Entities”
means, collectively, the Company and NuChem Pharmaceuticals Inc.;



“Company Intangible Property”
means the Intangible Property owned or licensed by or to the Company or any other of the Company Entities or in which the Company
or any other of the Company Entities has an interest;



“DEA” has the meaning
given to it in paragraph 7.1.27;



“Defaulted Shares”
has the meaning given to it in paragraph 13.2;



“Environmental Laws”
means any applicable law, regulation, order, judgment, injunction, permit, license, authorization or other binding requirement
relating to human health or safety or the regulation, protection, cleanup or restoration of the environment or natural resources,
including those relating to the distribution, processing, generation, treatment, control, storage, disposal, transportation, other
handling or release or threatened release of Hazardous Substances;



“FDA” has the meaning
given to it in paragraph 7.1.27;



“Final Prospectus”
has the meaning given to it above;



“Financial Statements”
means (i) the audited consolidated financial statements of the Company as at and for the year ended May 31, 2013, the Auditors’
report thereon and the notes thereto, and (ii) the unaudited consolidated financial statements of the Company for the six month
period ended November 30, 2013;



3







“FINRA” means Financial
Industry Regulatory Authority, Inc.



“Governmental Authority”
means any federal, provincial, state, municipal, local or other governmental or public department, commission, board, bureau, agency,
instrumentality or body, domestic or foreign, any subdivision or authority of any of the foregoing or any quasi-governmental, self-regulatory
organization or private body exercising any regulatory, expropriation or taxing authority under or for the account of its members
or any of the foregoing;



“Governmental Licences”
has the meaning given to it in paragraph 7.1.27;



“Hazardous Substances”
has the meaning given to it in paragraph 7.1.29;



“Health Canada” has
the meaning given to it in paragraph 7.1.27;



“Indemnified Parties”
has the meaning given to it in paragraph 9.1;



“Indemnifying Party”
has the meaning given to it in paragraph 9.1;



“Initial Preliminary Prospectus”
has the meaning given to it above;



“Intangible Property”
means all patents, patentable subject matter, copyrights, registered and unregistered trade-marks, service marks, domain names,
trade-names, logos, commercial symbols, industrial designs (including applications for all of the foregoing and renewals, divisions,
continuations, continuations-in-part, extensions and reissues, where applicable, relating thereto), inventions, licences, sublicences,
trade secrets, know-how, confidential and proprietary information, patterns, drawings, computer software, databases and all other
intellectual property, whether registered or not, owned by, licensed to or used by a person, in any format or medium whatsoever;



“Knowledge” means information
to the best of the knowledge, after due inquiry, of the following persons: Dr. William Rice, Gregory Chow, Avanish Vellanki and
Elizabeth Williams and includes any information that they ought reasonably to have known;



“Lead Underwriter”
has the meaning given to it above;



“marketing materials”
has the meaning ascribed thereto in NI 41-101;



“Material Adverse Effect”
means, in respect of the Company, any fact, event, effect or change, as the case may be, that
(i) is or is reasonably likely to be materially adverse to the results of operations, financial condition, prospects, business,
assets, capital, liabilities (contingent or otherwise) or operations of the Company Entities (taken as a whole) or (ii) would result
in any Offering Document containing a misrepresentation;



“NI 41-101” means National
Instrument 41-101 General Prospectus Requirements, as amended and replaced;



4







“NI 44-101” means National
Instrument 44-101 Short Form Prospectus Distributions, as amended and replaced;



“Offered Securities”
has the meaning given to it above;



“Offered Shares” has
the meaning given to it above;



“Offering” means the
offering of Offered Securities pursuant to the Final Prospectus as described under the “Plan of Distribution” section
thereof;



“Offering Documents”
means the Initial Preliminary Prospectus, the Amended and Restated Preliminary Prospectus, the Final Prospectus, the U.S. Placement
Memorandum (as defined herein) and any Amendment;



“Offering Price” has
the meaning given to it above;



“Over-Allotment Closing Time”
has the meaning given to it in paragraph 8.3;



“Over-Allotment Expiry Date”
has the meaning given to it above;



“Over-Allotment Option”
has the meaning given to it above;



“Over-Allotment Shares”
has the meaning given to it above;



“Passport Decision Document”
means a decision document issued by the applicable Securities Commission, as principal regulator, pursuant to the Passport System
and which evidences the receipt by the Securities Commissions in each of the other Qualifying Jurisdictions for the Initial Preliminary
Prospectus, the Amended and Restated Preliminary Prospectus, the Final Prospectus or any Amendment, as the case may be;



“Passport System” means
the passport system procedures provided for under National Policy 11-202 Process for Prospectus Reviews in Multiple Jurisdictions;



“person” means any
individual, partnership, limited partnership, joint venture, sole proprietorship, company or corporation, trust, trustee, unincorporated
organization, a government or an agency or political subdivision thereof;



“Purchase Price” has
the meaning given to it above;



“Qualification Deadline”
means 5:00 p.m. (Toronto time) on April 3, 2014 or such later date and time as the Company and the Lead Underwriter, on behalf
of the Underwriters, may mutually agree upon in writing;



“Qualifying Jurisdictions”
mean, collectively, all of the provinces of Canada other than Quebec;



“Refusing Underwriter”
has the meaning given to it in paragraph 13.2;



“Reviewing Authority”
has the meaning given to it above;



5







“ROTH” has the meaning
given to it above;



“Rule 144A” means Rule
144A under the U.S. Securities Act;



“SEC” means the United
States Securities and Exchange Commission;



“Securities Commission”
means the applicable securities commission or regulatory authority in each of the Qualifying Jurisdictions;



“Securities Laws” mean,
collectively, and, as the context may require, the applicable securities laws of each of the Qualifying Jurisdictions, and the
respective regulations and rules made under those securities laws together with all applicable policy statements, instruments,
blanket orders and rulings of the Securities Commissions and all discretionary orders or rulings, if any, of the Securities Commissions
made in connection with the transactions contemplated by this Agreement together with applicable published policy statements of
the Canadian Securities Administrators, as the context may require;



“Selling Firms” has
the meaning given to it in paragraph 2.1.1;



“Standard Listing Conditions”
has the meaning given to it in paragraph 5.2;



“Stock Exchange” means
the Toronto Stock Exchange;



“template version”
has the meaning ascribed thereto in NI 41-101 and includes any revised template version of marketing materials as contemplated
by NI 41-101;



“Underwriters” has
the meaning given to it above;



“Underwriters’ Disclosure”
means disclosure in respect of one or more of the Underwriters provided to the Company in writing by an Underwriter for inclusion
in the applicable disclosure document;



“Underwriting Fee”
has the meaning given to it above and in paragraph 8.3;



“United States Purchaser”
means a person in the United States who agrees to purchase Offered Securities in accordance with Annex A attached hereto;



“U.S. Affiliates” has
the meaning given to it above;



“U.S. Exchange Act”
means the United States Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder;



“U.S. Placement Memorandum”
means the Initial Preliminary Prospectus, the Amended and Restated Preliminary Prospectus and the Final Prospectus supplemented
with wrap pages for the purpose of, among other things, describing restrictions imposed under the U.S. Securities Act;



“U.S. Securities Act”
means the United States Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder;



6







“U.S. Securities Laws”
means the applicable blue sky or securities legislation of any state or territory of the United States or the District of Columbia
and the rules and regulations promulgated thereunder, together with the U.S. federal securities laws, including, without limitation,
the U.S. Exchange Act and the U.S. Securities Act; and



“Work Fee” has the
meaning given to it above.



| | 1.2 | Whenever used in this Agreement, the terms “affiliate”, “associate”, “distribution”,
“misrepresentation”, “material fact” and “material change” shall, except to the extent modified
herein or as the context requires, have the meanings given to such terms, and “distribution” shall include a “distribution
to the public” as defined, under applicable Securities Laws.
| | --- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 1.3 | Whenever used in this Agreement, words importing the singular number only shall include the plural
and vice versa and words importing the masculine gender shall include the feminine gender.
| | --- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 1.4 | All references to monetary amounts in this Agreement are to the lawful money of Canada.
| | --- | ---------------------------------------------------------------------------------------



| | 1.5 | All capitalized terms not otherwise defined herein shall have the meanings given to them in the
Offering Documents.
| | --- | -------------------------------------------------------------------------------------------------------------------



| | 2. | Covenants of the Underwriters
| | -- | -----------------------------



| | 2.1 | The Underwriters covenant with the Company that:
| | --- | ------------------------------------------------



| | 2.1.1 | during the course of the distribution of the Offered Securities to the public by or through the
Underwriters (other than ROTH), the Underwriters (other than ROTH) will offer the Offered Securities for sale to the public on
behalf of the Company, directly and through other investment dealers and brokers (the Underwriters (other than ROTH), together
with such investment dealers and brokers, are referred to herein as the “Selling Firms”) in the Qualifying Jurisdictions
only as permitted by and in accordance with applicable Securities Laws which, for greater certainty, shall include delivery by
the Underwriters (other than ROTH) of a copy of the Final Prospectus and any Amendment to each purchaser of Offered Securities
from the Underwriters (other than ROTH), only upon the terms and conditions set forth in this Agreement and that they will not,
directly or indirectly, offer Offered Securities for sale in any jurisdiction, other than the Qualifying Jurisdictions, that would
require the filing of a prospectus, registration statement, offering memorandum or similar document or would result in the Company
having any reporting or other obligation in such jurisdiction (other than a Form D in the United States in connection with any
private placement of the Offered Securities in the United States). In particular, the Underwriters acknowledge that the Offered
Securities have not been and will not be registered under the U.S. Securities Act and may not be offered or sold within the United
States, except as hereinafter provided in accordance with the exemption from the registration requirements of the U.S. Securities
Act provided by Rule 144A. The Underwriters make the representations, warranties and covenants applicable to them in Annex A hereto
and agree, on behalf of themselves and their U.S. Affiliates, as applicable, for the benefit of the Company, to comply with the
selling restrictions imposed by the laws of the United States and described in Annex A hereto, which forms part of this Agreement.
They also agree to obtain such an agreement from each Selling Firm. For greater certainty, ROTH will not, directly or indirectly,
solicit offers to purchase or sell Offered Securities in Canada.
| | ----- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



7







| | 2.1.2 | For the purposes of this paragraph 2, the Underwriters shall be entitled to assume that the
Offered Securities are qualified for distribution in any province of Canada referred to in the Passport Decision Document for the
Final Prospectus obtained from the Reviewing Authority following the filing of the Final Prospectus until the Underwriters receive
written notice to the contrary from the Company or the applicable Securities Commissions.
| | ----- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 2.1.3 | Notwithstanding the foregoing provisions of this paragraph 2.1, no Underwriter will be liable
to the Company with respect to a default by another Underwriter or a Selling Firm (that is not an affiliate of such Underwriter)
appointed by another Underwriter under this paragraph 2.1;
| | ----- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 2.1.4 | they will complete and will use all reasonable efforts to cause the Selling Firms, if any, to complete
the distribution of Offered Securities as promptly as possible after the Closing Time or Over-Allotment Closing Time, as applicable,
and the Lead Underwriter will (a) notify the Company when, in its opinion, the distribution of the Offered Securities shall have
ceased and (b) provide a breakdown of the number of Offered Securities distributed in each Qualifying Jurisdiction where such breakdown
is required for the purpose of calculating fees payable to, or reimbursable by, a Securities Commission;
| | ----- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 2.1.5 | after the Underwriters have made a reasonable effort to sell all of the Offered Shares to the public
at the Offering Price, the Underwriters may decrease the Offering Price for the Offered Shares, provided that the Purchase Price
payable by the Underwriters to the Company at the Closing Time shall not be decreased;
| | ----- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 2.1.6 | upon the request of the Company, the Underwriters will provide the Stock Exchange with a letter
setting forth the anticipated distribution of the Offering based upon subscriptions for the Offered Securities received as of the
date of such request;
| | ----- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 2.1.7 | they will not make any representations or warranties with respect to the Company or the Offered
Securities other than as set forth in this Agreement, the Amended and Restated Preliminary Prospectus, the Final Prospectus, the
U.S. Placement Memorandum, any Amendment or otherwise with the written approval of the Company, acting reasonably;
| | ----- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 2.1.8 | provided that they are satisfied, in their sole discretion that it is responsible for them to do
so, they will execute and deliver to the Company the certificates required to be executed by the Underwriters under applicable
Securities Laws in connection with the Amended and Restated Preliminary Prospectus, the Final Prospectus and any Amendment; and
| | ----- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



8







| | 2.1.9 | the obligations of the Underwriters under this Agreement are several and not joint and several,
and no Underwriter will be liable for any act, omission, default or conduct by any other Underwriter or any Selling Firm (that
is not an affiliate of such Underwriter) appointed by any other Underwriter.
| | ----- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 2.2 | ROTH hereby covenants and agrees with the Company that:
| | --- | -------------------------------------------------------



| | 2.2.1 | it will not sell or offer to sell, nor allow any agent or Selling Firm acting on behalf of ROTH
in connection with the Offering to sell or offer to sell, any of the Offered Securities to any person resident in Canada or for
the benefit of a person resident in Canada;
| | ----- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 2.2.2 | concurrent with the closing of the Offering, ROTH will deliver to the Lead Underwriter, on behalf
of the Underwriters (other than ROTH), with a copy to the Company, an “all-sold” certificate confirming that neither
ROTH nor any of the agents or Selling Firms acting on ROTH’s behalf in connection with the Offering, has offered or sold
any of the Offered Securities to any person resident in Canada or for the benefit of a Person resident in Canada; and
| | ----- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 2.2.3 | it shall include a statement in the confirmation slip or other notice provided to any purchaser
of the Offered Securities sold by ROTH that it is ROTH’s understanding that such purchaser is not a resident of Canada nor
is such purchaser holding such Offered Securities on behalf of or for the benefit of a person resident in Canada.
| | ----- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 3. | Covenants of the Company
| | -- | ------------------------



| | 3.1 | The Company covenants and agrees with the Underwriters that:
| | --- | ------------------------------------------------------------



| | 3.1.1 | it has prepared and filed the Initial Preliminary Prospectus in each Qualifying Jurisdiction (and
has obtained a Passport Decision Document therefor from the Reviewing Authority) and other related documents in respect of the
proposed distribution of the Offered Securities;
| | ----- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 3.1.2 | it shall fulfill to the satisfaction of the Underwriters (other than ROTH) all legal requirements
to be fulfilled by it to enable the Offered Securities to be offered for sale and sold to the public in the Qualifying Jurisdictions
by or through the Selling Firms who comply with all applicable Securities Laws in each of the Qualifying Jurisdictions; such fulfillment
shall include, without limiting the generality of the foregoing, compliance with all applicable Securities Laws including, without
limitation, (i) the Company obtaining a Passport Decision Document for the Amended and Restated Preliminary Prospectus no later
than 5:00 p.m. (Toronto time) on March 27, 2014 and delivering a copy thereof to the Underwriters and their counsel; and (ii) the
Company preparing and, forthwith after any comments with respect to the Amended and Restated Preliminary Prospectus have been received
from and have been resolved with the Reviewing Authority, but not later than the Qualification Deadline, obtaining a Passport Decision
Document for the Final Prospectus and delivering a copy thereof to the Underwriters and their counsel;
| | ----- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



9







| | 3.1.3 | it shall fulfill to the satisfaction of the Underwriters all legal requirements to be fulfilled
by it as required under U.S. Securities Laws to offer and sell the Offered Securities in accordance with Annex A hereto in transactions
exempt from the registration requirements of the U.S. Securities Act pursuant to Rule 144A and applicable state securities laws
in the United States;
| | ----- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 3.1.4 | until the completion of the distribution of the Offered Securities, it shall allow and assist the
Underwriters to participate fully in the preparation of the Amended and Restated Preliminary Prospectus and the Final Prospectus
and any Amendment and shall allow the Underwriters to conduct all “due diligence” investigations which the Underwriters
may reasonably require to fulfill the Underwriters’ obligations as underwriters, to enable the Underwriters to avail themselves
of a defence to any claim for misrepresentation in the Amended and Restated Preliminary Prospectus, the Final Prospectus and any
Amendment and to enable the Underwriters responsibly to execute any certificate required to be executed by the Underwriters in
any such documentation. It shall be a condition precedent to the Underwriters’ execution of any certificate in the Amended
and Restated Preliminary Prospectus, the Final Prospectus and any Amendment that the Underwriters be satisfied, acting reasonably,
as to the form and content of the document and the execution thereby of such certificate shall be conclusive evidence of such satisfaction;
| | ----- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 3.1.5 | it will comply with section 57 of the Securities Act (Ontario) and with the other comparable
provisions of the applicable Securities Laws and U.S. Securities Laws and during the period from the date of signing the Amended
and Restated Preliminary Prospectus to the date of completion of distribution of the Offered Securities, will promptly notify the
Underwriters in writing of the full particulars of any material change, actual, anticipated, contemplated, proposed or threatened,
in the business, financial condition, assets, liabilities (contingent or otherwise), results of operations or prospects of the
Company (on a consolidated basis) or of any change in any material fact contained or referred to in the Amended and Restated Preliminary
Prospectus, the Final Prospectus, the U.S. Placement Memorandum or in any Amendment, and of the existence of any material fact
which is, or may be, of such a nature as to render the Amended and Restated Preliminary Prospectus, the Final Prospectus, the U.S.
Placement Memorandum or any Amendment, untrue, false or misleading in a material respect or result in a misrepresentation. It shall,
to the satisfaction of the Underwriters and their counsel, acting reasonably, promptly comply with all applicable filing and other
requirements under the Securities Laws and the U.S. Securities Laws as a result of such change. It shall, in good faith, first
discuss with the Lead Underwriter any change in circumstances (actual, proposed or, within the Company’s Knowledge, threatened)
which is of such a nature that there is reasonable doubt whether notice need be given to the Underwriters pursuant to this paragraph 3.1.5
and, in any event, prior to making any filing referred to in this paragraph 3.1.5. For greater certainty but not so as to limit
the generality of the foregoing, it is understood and agreed that, during the period from the date of signing the Amended and Restated
Preliminary Prospectus to the date of completion of the distribution of the Offered Securities, if the Underwriters and the Company
determine, acting reasonably, that a material change or change in a material fact has occurred which makes untrue or misleading
any statement of a material fact contained in the Amended and Restated Preliminary Prospectus, the Final Prospectus or any Amendment,
or which may result in a misrepresentation, the Company will:
| | ----- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



10







| | 3.1.5.1 | prepare and file promptly any Amendment which in its opinion, acting reasonably, may be necessary
or advisable, after consultation with the Underwriters; and
| | ------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 3.1.5.2 | contemporaneously with filing the Amendment under the applicable laws of the Qualifying Jurisdictions,
deliver to the Underwriters:
| | ------- | -----------------------------------------------------------------------------------------------------------------------------------



| | 3.1.5.2.1 | a copy of the Amendment, signed as required by the Securities Laws;
| | --------- | -------------------------------------------------------------------



| | 3.1.5.2.2 | a copy of all documents relating to the proposed distribution of the Offered Securities and filed
with the Amendment under the applicable Securities Laws; and
| | --------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 3.1.5.2.3 | such other documents as the Underwriters shall reasonably require;
| | --------- | ------------------------------------------------------------------



| | 3.1.6 | it will ensure that, at the Closing Time, the Offered Shares will be conditionally approved for
listing on the Stock Exchange, subject only to compliance with Standard Listing Conditions; and
| | ----- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 3.1.7 | it will use commercially reasonable efforts to maintain the Company’s status as a reporting
issuer not in default under Securities Laws and maintain the listing of the Common Shares (including the Offered Securities) on
the Stock Exchange for a period of 12 months from the Closing Date, provided, for greater certainty, that nothing in this paragraph
3.1.7 shall prevent the Company from participating in a merger, business combination or similar transaction.
| | ----- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 3.2 | During the period commencing on the date hereof and ending on the date the Lead Underwriter, on
behalf of the Underwriters, notifies the Company of the completion of the distribution of the Offered Securities, the Company will
promptly inform the Underwriters of the full particulars of:
| | --- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 3.2.1 | the receipt of any comments from the Securities Commissions with respect to the Amended and Restated
Preliminary Prospectus, Final Prospectus or any Amendment;
| | ----- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 3.2.2 | any request of any Securities Commission for any Amendment or for any additional information in
connection with the Offering;
| | ----- | -----------------------------------------------------------------------------------------------------------------------------



| | 3.2.3 | the issuance by any Securities Commission, the Stock Exchange or any other Governmental Authority
of any order to cease or suspend trading of any securities of the Company or of the institution or threat of institution of any
proceedings for that purpose; and
| | ----- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



11







| | 3.2.4 | any notice or other correspondence received by it from any Governmental Authority requesting information,
meeting or hearing or commencing or threatening any investigation into the Company or its business that could reasonably be expected
to have a material adverse effect on the business, financial condition, assets, liabilities (contingent or otherwise), results
of operations or prospects of the Company Entities (taken together) or the completion of the Offering.
| | ----- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 3.3 | The Company will use reasonable commercial efforts to promptly do, make, execute, deliver or cause
to be done, made, executed or delivered, all such acts, documents and things as the Underwriters may reasonably require from time
to time for the purpose of giving effect to the transactions contemplated by this Agreement and take all such steps as may be reasonably
within its power to implement the transactions contemplated by this Agreement.
| | --- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 3.4 | The Company will apply the net proceeds from the issue and sale of the Offered Securities substantially
in accordance with the disclosure set forth under the heading “Use of Proceeds” in the Final Prospectus and any Amendment.
| | --- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 3.5 | The Company shall cause each of its directors and senior officers to enter into a lock-up agreement
in the form of agreement contemplated in Schedule “A” hereto.
| | --- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 3.6 | The Company makes the representations, warranties and covenants applicable to it in Annex A hereto,
which forms part of this Agreement.
| | --- | ---------------------------------------------------------------------------------------------------------------------------------------



| | 4. | Marketing Materials
| | -- | -------------------



| | 4.1 | The Company covenants and agrees with the Underwriters that during the distribution of the Offered
Securities:
| | --- | --------------------------------------------------------------------------------------------------------------



| | 4.1.1 | it shall prepare, in consultation with the Lead Underwriter, and approve in writing, prior to such
time marketing materials are provided to potential investors, any marketing materials reasonably requested to be provided by the
Underwriters to any potential investor of Offered Securities, such marketing materials to comply with Securities Laws and to be
acceptable in form and substance to the Lead Underwriter and its counsel, acting reasonably, and approved in writing by the Lead
Underwriter as contemplated by the Securities Laws;
| | ----- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 4.1.2 | it shall file a template version with the Securities Commissions as soon as reasonably practicable
after such marketing materials are so approved in writing by it and the Lead Underwriter and in any event on or before the day
the marketing materials are first provided to any potential investor of Offered Securities;
| | ----- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 4.1.3 | any comparables (as defined in NI 41-101) shall be removed from the template version in accordance
with NI 44-101 prior to filing such template version with the Securities Commission and a complete template version containing
such comparables and any disclosure relating to the comparables, if any, shall be delivered to the Securities Commissions by the
Company; and
| | ----- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



12







| | 4.1.4 | following the approvals set forth in this paragraph 4.1, the Underwriters may provide a limited-use
version (as defined in NI 41-101) of such marketing materials to potential investors of Offered Securities in accordance with Securities
Laws.
| | ----- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 4.2 | The Company and the Underwriters, on a several basis, covenant and agree, during the distribution
of the Offered Securities:
| | --- | ----------------------------------------------------------------------------------------------------------------------------



| | 4.2.1 | not to provide any potential investor of Offered Securities with any marketing materials unless
a template version of such marketing materials has been filed by the Company with the Securities Commissions on or before the day
such marketing materials are first provided to any potential investor of Offered Securities;
| | ----- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 4.2.2 | not to provide any potential investor with any materials or information in relation to the distribution
of the Offered Securities or the Company other than: (A) such marketing materials that have been approved and filed in accordance
with paragraph 4.1; (B) the Offering Documents in accordance with this Agreement; and (C) any standard term sheets (as defined
in NI 41-101) approved in writing by the Company and the Lead Underwriter; and
| | ----- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 4.2.3 | that any marketing materials approved and filed in accordance with paragraph 4.1 and any standard
term sheets approved in writing by the Company and the Lead Underwriter, shall only be provided to potential investors in the Qualifying
Jurisdictions.
| | ----- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 5. | Deliveries
| | -- | ----------



The Company shall cause
to be delivered to the Lead Underwriter on behalf of the Underwriters:



| | 5.1 | contemporaneously with the filing thereof with the Securities Commissions, copies of the Amended
and Restated Preliminary Prospectus, theFinal Prospectus and any Amendment, a copy of any other document required to be
filed by the Company under the Securities Laws in connection therewith, in each case, signed, where applicable, as required by
the Securities Laws and the U.S. Placement Memorandum. The Company has previously delivered to the Underwriters copies of the Initial
Preliminary Prospectus as approved, signed and certified as required by Securities Laws;
| | --- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 5.2 | at the time of the delivery to the Lead Underwriters pursuant to this paragraph 5 of the Final
Prospectus or any Amendment, evidence satisfactory to the Underwriters of the approval of the listing on the Stock Exchange of
the Offered Securities, subject only to satisfaction by the Company of customary post-closing conditions imposed by the Stock Exchange
in similar circumstances (the “Standard Listing Conditions”);
| | --- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 5.3 | at the Closing Time, the Over-Allotment Closing Time and at the time of the delivery to the Lead
Underwriter pursuant to this paragraph 5 of the Final Prospectus or any Amendment, a comfort letter of the Auditors dated
the Closing Date, Over-Allotment Closing Date or the date of theFinal Prospectus or Amendment, as the case may be, and
addressed to the Underwriters, in form and substance reasonably satisfactory to the Underwriters, relating to the financial information
contained or incorporated by reference in the Final Prospectus or Amendment, as the case may be, and matters involving changes
or developments since the respective dates of which the financial information is given to a date not more than two Business Days
prior to the date of such letter, which letter shall be in addition to the Auditors’ report in the Final Prospectus or Amendment;
| | --- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



13







| | 5.4 | without charge, at those delivery points in the Qualifying Jurisdictions as the Underwriters may
reasonably request, as soon as possible and in any event to the City of Toronto no later than 12:00 noon (local time) on the first
Business Day, and to other cities no later than 12:00 noon (local time) on the second Business Day, after the Passport Decision
Document has been issued to the Company therefor and thereafter from time to time during the distribution of the Offered Securities,
as many commercial copies of the Amended and Restated Preliminary Prospectus and the Final Prospectus and the corresponding U.S.
Placement Memorandum, as the Underwriters may reasonably request. They shall similarly cause to be delivered commercial copies
of any Amendment, but only to the extent that, under applicable Securities Laws, copies thereof may be required to be delivered
to purchasers or prospective purchasers of the Offered Securities; and
| | --- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 5.5 | during the period commencing on the date hereof and ending on the date of completion of the distribution
of the Offered Securities, the Company will promptly provide to the Lead Underwriter and its counsel drafts of any press release
of the Company or the Company Entities relating to any of the Company Entities or the Offering, for review and approval by the
Lead Underwriter and its counsel, such approval not to be unreasonably withheld, prior to issuance.
| | --- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 6. | Representations and Warranties - Prospectus
| | -- | -------------------------------------------



| | 6.1 | The delivery to the Lead Underwriter of the documents referred to in paragraphs 5.1 and 5.4
hereof shall constitute the representation and warranty of the Company to the Underwriters that: each such document at the time
of its respective delivery fully complied with the requirements of the Securities Laws and U.S. Securities Laws, as applicable,
pursuant to which it was or is prepared, and, as applicable, filed and that all the information and statements contained therein
(except information and statements relating solely to Underwriters’ Disclosure) are at the respective dates thereof, true
and correct in all material respects, contain no misrepresentation and constitute full, true and plain disclosure of all material
facts relating to the Company and the other Company Entities, taken together, and the Offered Securities as required by applicable
Securities Laws and U.S. Securities Laws, as applicable.
| | --- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 6.2 | The Company consents to the use by the Underwriters of the documents referred to in paragraphs 5.1
and 5.4 hereof in connection with the distribution of the Offered Securities in the Qualifying Jurisdictions and the United States
subject to the provisions of this Agreement.
| | --- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7. | Representations and Warranties - General
| | -- | ----------------------------------------



| | 7.1 | The Company represents and warrants to the Underwriters, and acknowledges that each Underwriter
is relying upon such representations and warranties, that:
| | --- | ----------------------------------------------------------------------------------------------------------------------------------------------------------



14







| | 7.1.1 | Each of the Company Entities is a duly incorporated, amalgamated or continued company and validly
existing and in good standing under the laws of its jurisdiction of incorporation, amalgamation or continuation and no proceedings
have been instituted or, to the Company’s Knowledge, are pending for the dissolution or liquidation of the Company or Company
Entity, as applicable. Each of the Company Entities has the corporate power and capacity to own its assets currently owned by it
and to carry on its business currently carried on by it as disclosed in the Offering Documents. Each of the Company Entities is
duly qualified, licensed or registered to carry on business in all jurisdictions except where the failure to be so registered,
licensed or qualified would result in a Material Adverse Effect.
| | ----- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.2 | NuChem Pharmaceuticals Inc. is the only subsidiary of the Company and has no active business or
operations and no material assets or liabilities. The Company owns 80% of the issued and outstanding voting share capital and 100%
of the issued and outstanding non-voting preference share capital of NuChem Pharmaceuticals Inc. and:
| | ----- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



7.1.2.1        all
such shares are legally and beneficially owned by the Company free and clear of all liens, charges and encumbrances of any kind
whatsoever;



7.1.2.2        no
person has any agreement, or option or right or privilege (whether preemptive or contractual) capable of becoming an agreement
for the purchase of all or any part of the securities of NuChem Pharmaceuticals Inc.; and



7.1.2.3        all
such shares have been validly issued and are outstanding as fully paid and non-assessable.



Except for
the shares of NuChem Pharmaceuticals Inc. held by the Company, neither the Company nor the other Company Entities own securities
or ownership interest in any other person which are material to the Company Entities, taken as a whole.



| | 7.1.3 | The authorized capital of the Company consists of an unlimited number of Common Shares of which
62,335,827 Common Shares were issued and outstanding as of the close of business on March 26, 2014 as fully paid and non-assessable
shares in the capital of the Company.
| | ----- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.4 | Other than options to purchase 6,566,223 Common Shares, warrants to purchase 23,367,124 Common
Shares, deferred share units convertible into 780,000 Common Shares and promissory notes convertible into a maximum of 2,000,000
Common Shares, no person has any agreement, option, right or privilege, whether pre-emptive, contractual or otherwise, capable
of becoming an agreement for the purchase, acquisition, subscription for or issuance of any of the unissued shares of the Company
or any other Company Entity, or other securities convertible, exchangeable or exercisable for shares of the Company or any other
Company Entity.
| | ----- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.5 | The Company is not party to and, to the Company’s Knowledge, there are no shareholders’
agreements, pooling agreements, voting trusts or other similar agreements with respect to the ownership or voting of any of the
securities of the Company or pursuant to which any person may have any right or claim in connection with any existing or past equity
interest in the Company.
| | ----- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



15







| | 7.1.6 | The Company has all requisite power and capacity to enter into and perform its obligations under
this Agreement. This Agreement has been duly authorized, executed and delivered by the Company, and constitutes a legal, valid
and binding obligation of the Company enforceable against the Company in accordance with its terms subject to bankruptcy, insolvency,
creditor arrangement laws and laws affecting creditors’ rights generally and equitable relief and except as rights to indemnity
and contribution may be limited by applicable laws.
| | ----- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.7 | The issue and sale of the Offered Securities, the execution and delivery of and the compliance
by the Company with all of the provisions of this Agreement and the consummation of the transactions herein contemplated do not
and will not conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under
(whether after notice or lapse of time or both):
| | ----- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



7.1.7.1        any
statute, rule or regulation applicable to the Company, including, without limitation, the Securities Laws;



7.1.7.2        the
articles, by-laws or resolutions of the directors or the shareholders of the Company which are in effect at the date hereof;



7.1.7.3        any
mortgage, note, indenture, contract, agreement, joint venture, partnership, instrument, lease or other document to which the Company
is a party or by which it is bound; or



7.1.7.4        any
judgment, decree or order of any Governmental Authority binding the Company or its property or assets.



| | 7.1.8 | No consent, approval, authorization, order, registration, clearance or qualification of or with
any Governmental Authority is required for the issue and sale of the Offered Securities or the consummation by the Company of the
transactions contemplated by this Agreement, except such as have been, or will have been prior to the Closing Time, obtained under
the Securities Laws in connection with the purchase and distribution of the Offered Securities by the Underwriters.
| | ----- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.9 | The Company meets the requirements under the Securities Laws, including the rules and procedures
established pursuant to NI 44-101, for the distribution of the Offered Securities in each of the Qualifying Jurisdictions.
| | ----- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.10 | The Company has all requisite power, capacity and authority to execute and deliver the Offering
Documents (including any marketing materials) and to file such documents (other than the U.S. Placement Memorandum) with the Securities
Commissions, and all necessary action has been taken by the Company to authorize the execution and delivery of the Offering Documents
(including any marketing materials) and to file such documents (other than the U.S. Placement Memorandum) with the Securities Commissions.
| | ------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



16







| | 7.1.11 | The Offered Securities have been duly authorized for issuance to the Underwriters pursuant to this
Agreement and, when issued and delivered by the Company against payment of the consideration set forth herein, the Offered Securities
will be validly issued and fully paid and non-assessable; the issuance of the Offered Securities is not subject to the preemptive
or similar rights of any person.
| | ------ | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.12 | The description of the Offered Securities set forth in each of the Offering Documents, insofar
as they purport to constitute a summary of the terms of the Offered Securities, are fair and adequate summaries of the matters
referred to therein.
| | ------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.13 | The Common Shares that are currently issued and outstanding are listed and posted for trading on
the Stock Exchange and the Company is not in default of its listing requirements on the Stock Exchange in any material respect.
| | ------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.14 | No order having the effect of ceasing or suspending the distribution of the Offered Securities
has been issued by any Governmental Authority and no proceeding for that purpose has been initiated or, to the Company’s
Knowledge, are pending, contemplated or threatened by any Governmental Authority.
| | ------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.15 | Computershare Investor Services Inc., through its offices in the City of Toronto, Ontario has been
duly appointed as the registrar and transfer agent for the Common Shares.
| | ------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.16 | The Company is a reporting issuer or the equivalent in the Qualifying Jurisdictions and is not
in default of any of the requirements of Securities Laws.
| | ------ | --------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.17 | Each document filed or to be filed with the Securities Commissions and incorporated by reference
in any Offering Document, when such document was or is filed with the Securities Commissions, complied as to form or will comply
as to form when so filed in all material respects with the applicable requirements of Securities Laws, except in those respects
for which exemptive relief has been obtained, and none of such documents, as of their respective dates, contained or will contain
any misrepresentation.
| | ------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.18 | The Financial Statements have been prepared in accordance with applicable laws and International
Financial Reporting Standards applied on a consistent basis throughout the periods referred to therein, present fairly, in all
material respects, the financial position and condition of the Company on a consolidated basis as at the date thereof and the results
of its operations and the changes in its cash flows for the period then ended, and there were no liabilities, contingent, contractual
or otherwise, of the Company as of the dates set forth therein, other than those disclosed in the Financial Statements.
| | ------ | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



17







| | 7.1.19 | The Company maintains a system of internal accounting controls sufficient to provide reasonable
assurances that (i) transactions are executed in accordance with management’s general or specific authorizations, (ii) transactions
are recorded as necessary to permit preparation of financial statements in conformity with International Financial Reporting Standards
and to maintain asset accountability, (iii) access to assets is permitted only in accordance with management’s general or
specific authorization, (iv) the recorded accountability for assets is compared with existing assets at reasonable intervals and
appropriate action is taken with respect to differences, (v) material information relating to each of the Company Entities is made
known to those within the Company Entity responsible for the preparation of the financial statements during the period in which
the financial statements have been prepared and that such material information is disclosed to the public within the time periods
required by applicable laws, and (vi) all significant deficiencies and material weaknesses in the design or operation of such internal
controls that could adversely affect the Company’s ability to disclose to the public information required to be disclosed
by it in accordance with applicable law and all fraud, whether or not material, that involves management or employees that have
a significant role in the Company’s internal controls have been disclosed to the audit committee of the Company.
| | ------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.20 | All of the material transactions of the Company and each of the other Company Entities have been
promptly and properly recorded or filed in or with their respective books or records and their respective minute books contain
all of their material transactions, all records of the meetings and proceedings of their directors, shareholders and other committees,
if any, since their respective incorporations.
| | ------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.21 | To the Company’s Knowledge, the Auditors (including any former auditors, as applicable),
who have reported on the consolidated financial statements of the Company incorporated by reference in each of the Offering Documents,
are independent with respect to the Company within the meaning of Section 161 of the Canada Business Corporations Act and
Securities Laws.
| | ------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.22 | There has not been any reportable event (within the meaning of National Instrument 51-102 Continuous
Disclosure Obligations) with the current or any former auditors of the Company in the past three financial years.
| | ------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.23 | Except as disclosed in the Offering Documents, none of the insiders of the Company (as defined
in Securities Laws), or any associate or affiliate of any of such insiders, had or has any material interest, direct or indirect,
in any transaction or any proposed transaction of any Company Entity which, as the case may be, materially affects, is material
to or will materially affect the Company Entities (taken as a whole).
| | ------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.24 | Except as disclosed in the Offering Documents, there are no related party transactions within the
meaning of Multilateral Instrument 61-101 involving the Company.
| | ------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.25 | Except as disclosed in the Offering Documents, there has not occurred any material adverse change,
or any development involving a prospective material adverse change, in the condition, financial or otherwise, or in the earnings,
business or operations of the Company Entities (taken together) and no event has occurred or circumstances exist which would be
reasonably expected to result in a material adverse change in the condition, financial or otherwise, or in the earnings, business
or operations of the Company Entities (taken together).
| | ------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



18







| | 7.1.26 | The Company has not made any significant acquisition as such term is defined in Part 8 of National
Instrument 51-102 in the current financial year or prior financial years in respect of which historical and/or pro forma financial
statements would be required to be included or incorporated by reference into the Offering Documents, and, except as disclosed
in the Offering Documents, the Company has not entered into any agreement or arrangement in respect of a transaction that would
be a proposed significant acquisition (as such term is defined in National Instrument 44-101).
| | ------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.27 | Each of the Company Entities has conducted and is conducting its business in compliance in all
material respects with all applicable federal, provincial, state and municipal laws, rules, regulations, tariffs, orders and directives
of each jurisdiction in which it carries on business. Each Company Entity possesses such permits, certificates, licences, approvals,
registrations, qualifications, consents and other authorizations (collectively, “Governmental Licences”) issued by
the appropriate Governmental Authority necessary to conduct the business now operated by it in all jurisdictions in which it carries
on business, including without limitation those required by the Health Products and Food Branch of Health Canada (“Health
Canada”), the United States Food and Drug Administration (the “FDA”), the United States Drug Enforcement Administration
(the “DEA”) and any foreign regulatory authorities performing functions similar to those performed by Health Canada,
FDA, or DEA other than individually or in aggregate would not have a Material Adverse Effect. Each Company Entity is in material
compliance with the terms and conditions of all such Governmental Licences. All of such Governmental Licences are in good standing,
valid and in full force and effect. The Company has no reason to believe that any party granting any such Governmental Licenses
is considering limiting, suspending, modifying, withdrawing or revoking the same in any material respect.
| | ------ | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.28 | Each of the Company Entities has operated and is currently in material compliance with all applicable
rules, regulations and policies of Health Canada the FDA, DEA, or any other Governmental Authority having jurisdiction over it
and its activities. The research, pre-clinical and clinical validation studies and other studies and tests conducted by or on behalf
of or sponsored by a Company Entity or in which a Company Entity or its products or product candidates have participated were and,
if still pending, are being conducted in all material respects in accordance with good clinical practice and medical standard-of-care
procedures including in accordance with the protocols submitted to Health Canada, the FDA or any other Governmental Authority exercising
comparable authority and the Company does not have Knowledge of any other trials, studies or tests, the results of which reasonably
call into question the results of such studies and tests. The Company has not received any notices or other correspondence from
such regulatory authorities or any other Governmental Authority or any other person requiring the termination, suspension or material
modification of any such research, pre-clinical and clinical validation studies or other studies and tests. The Company has not
failed to submit to the FDA any necessary Investigational New Drug Application for a clinical trial it is conducting or sponsoring,
except where such failure would not, individually or in the aggregate, have a Material Adverse Effect. All such submissions and
any New Drug Application submission were in material compliance with applicable laws when submitted and no material deficiencies
have been asserted by the FDA with respect to any such submissions, except any deficiencies which could not, individually or in
the aggregate, have a Material Adverse Effect.
| | ------ | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



19







| | 7.1.29 | Except as would not have a Material Adverse Effect:
| | ------ | ---------------------------------------------------



7.1.29.1      (i) neither the Company nor any of the other Company Entities is in violation of any applicable Environmental Laws; (ii) the Company
Entities have all permits, authorizations and approvals required under any applicable Environmental Laws and each are in compliance
with their requirements; and (iii) there are no pending or, to the Company’s Knowledge, threatened administrative, regulatory
or judicial actions, suits, demands, demand letters, claims, liens, orders, directions, notices of non-compliance or violation
or alleging liability, investigation or proceedings relating to any applicable Environmental Law against the Company or any other
Company Entity, and, to the Company’s Knowledge, there are no facts or circumstances which would reasonably be expected to
form the basis for any such administrative, regulatory or judicial actions, suits, demands, demand letters, claims, liens, orders,
directions, notices of non-compliance or violation, investigation or proceedings;



7.1.29.2      neither
the Company nor any of the other Company Entities has not generated, manufactured, processed, distributed, used, treated, stored,
disposed of, transported or handled any pollutants, contaminants, chemicals or industrial toxic or hazardous waste or substances
(collectively, “Hazardous Substances”) in a manner that could result in a material liability; and



7.1.29.3      other
than in compliance with, and without attracting any material liability under, applicable laws, neither the Company nor any of the
other Company Entities has caused or permitted the release, in any manner whatsoever, of any Hazardous Substances on or from any
of its properties or assets or any such release on or from a facility owned or operated by third parties but with respect to which
any Company Entity is or may reasonably be alleged to have material liability or has received any notice that it is potentially
responsible for site clean-up or other corrective action under any applicable laws.



| | 7.1.30 | none of the Company Entities own real property and each of them has good and marketable title to
all personal property owned by it free and clear of all liens. Any real property or building held under lease by a Company Entity
is held by it under valid and subsisting leases enforceable against its respective lessors. With respect to each premises which
a Company Entity occupies as tenant, such Company Entity occupies such premises and has the exclusive right to occupy and use such
premises and each of the leases pursuant to which such Company Entity occupies such premises is in good standing and in full force
and effect;
| | ------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.31 | to the Company's knowledge, the Company and/or the other Company Entities owns, or has obtained
valid and enforceable licenses for, or otherwise has rights to all Intangible Property described in the Amended and Restated Preliminary
Prospectus;
| | ------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



20







| | 7.1.32 | the Company has no Knowledge that it lacks or will be unable to obtain any rights or licenses to
conduct the business of the Company Entities as proposed in the Amended and Restated Preliminary Prospectus;
| | ------ | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.33 | to the Company’s Knowledge, there is no infringement by any third party of any Company Intangible
Property;
| | ------ | -----------------------------------------------------------------------------------------------------------



| | 7.1.34 | there is no ongoing, pending or, to the Company’s Knowledge, threatened, action, suit, proceeding
or claim by others challenging the Company’s rights in or to any Company Intangible Property;
| | ------ | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.35 | there is no ongoing, pending or, to the Company’s Knowledge, threatened, action, suit, proceeding
or claim by others challenging the validity or enforceability of any Company Intangible Property;
| | ------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.36 | the Company has no Knowledge of any third parties who have rights to any Company Intangible Property
except for the ownership rights of the owners of the Company Intangible Property which are licensed to the Company and/or the other
Company Entities;
| | ------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.37 | there is no ongoing, pending, or to the Company’s Knowledge, threatened, action, suit, proceeding
or claim by others that the business as currently conducted, the Company or any of the other Company Entities infringes or otherwise
violates (or would infringe or otherwise violate upon commercialization of the Company’s products under development) any
Intangible Property of others;
| | ------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.38 | to the Company’s Knowledge, no information known to us to be “material to patentability”
(as such term is defined in section 1.56 of Title 37 - Code of Federal Regulations Patents, Trademarks, and Copyrights) has been
withheld by us with intention to deceive the United States Patent and Trademarks Office in connection with the prosecution of the
U.S. patents and applications owned by the Company or any of the other Company Entities;
| | ------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.39 | there is no ongoing, pending, or to the Company’s Knowledge, threatened, action suit, proceeding
or claim by others claiming breach of any license relating to the Company Intangible Property;
| | ------ | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.40 | except as would not have a Material Adverse Effect, each of the Company Entities has duly and on
a timely basis filed all foreign, federal, state, provincial and municipal tax returns required to be filed by it, has paid all
taxes due and payable and has paid all assessments and reassessments and all other taxes, governmental charges, penalties, interest
and other fines due and payable by it and which are claimed by any Governmental Authority to be due and owing and adequate provision
has been made for taxes payable for any completed fiscal period for which tax returns are not yet required to be filed;
| | ------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



21







| | 7.1.41 | there are no agreements, waivers or other arrangements providing for an extension of time with
respect to the filing of any tax return or payment of any tax, governmental charge or deficiency by any Company Entity;
| | ------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.42 | to the Company’s Knowledge, there are no actions, suits, proceedings, investigations or claims
threatened or pending against the Company in respect of taxes, governmental charges or assessments;
| | ------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.43 | there are no matters under discussion with any Governmental Authority relating to taxes, governmental
charges or assessments asserted by any such authority;
| | ------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.44 | no default exists under and no event has occurred which, after notice or lapse of time or both,
or otherwise, would constitute a default under or breach of, by a Company Entity, or any other person, any obligation, agreement,
covenant or condition contained in any contract, indenture, trust, deed, mortgage, loan agreement, note, lease or other agreement
or instrument to which a Company Entity is a party or by which a Company Entity or any of its properties may be bound, except to
the extent any such default does not have a Material Adverse Effect;
| | ------ | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.45 | the Company has procured and maintains adequate insurance against all reasonable insurable risks
with respect to its business, has not failed to give any notice or to present any material claim under any insurance policy in
a due and timely fashion, and all of the policies in respect of such insurance coverage are in good standing in all respects and
there are no material defaults thereunder;
| | ------ | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.46 | no general labour dispute with the employees of any of the Company Entities exists or, to the Company’s
Knowledge, is imminent;
| | ------ | -------------------------------------------------------------------------------------------------------------------------------



| | 7.1.47 | other than as disclosed to the Underwriters, none of the Company Entities has been served with
or otherwise received notice of any legal, governmental or regulatory proceedings, including any investigation, claim, complaint
or other similar proceeding and, to the Company’s Knowledge, there are no legal, governmental or regulatory proceedings (whether
or not purportedly on behalf of the Company) pending, to which any Company Entity is a party or of which any its property or assets
is the subject and to the Company’s Knowledge and other than as disclosed to the Underwriters, no such proceedings have been
threatened or contemplated;
| | ------ | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.48 | other than the Underwriters, there is no person, firm or corporation acting or, to the Company’s
Knowledge, purporting to act at the request of the Company, who is entitled to any brokerage or finder’s fee in connection
with the transactions contemplated herein; and
| | ------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7.1.49 | no representation or warranty by the Company in this Agreement and no statement contained in the
this Agreement or any certificate or other document furnished or to be furnished pursuant to this Agreement contains any untrue
statement of a material fact, or omits to state a material fact necessary to make the statements contained therein, in light of
the circumstances in which they are made, not misleading.
| | ------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



22







| | 8. | Closing of the Offering
| | -- | -----------------------



The closing of the purchase
and sale of the Offered Shares provided for in this Agreement shall be completed at the offices of McCarthy Tétrault LLP
located at Suite 5300, TD Bank Tower, 66 Wellington Street West, Toronto, Ontario, M5K 1E6, at the Closing Time.



| | 8.1 | The following are conditions precedent to the obligations of the Underwriters to purchase the Offered
Shares under this Agreement, which conditions may be waived in writing in whole or in part by the Lead Underwriter on behalf of
the Underwriters:
| | --- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 8.1.1 | receipt by the Underwriters of the following documents:
| | ----- | -------------------------------------------------------



8.1.1.1    a
favourable legal opinion, dated the Closing Date, from the Company’s counsel, McCarthy Tétrault LLP, with respect
to all such matters as the Underwriters may reasonably request, including, without limiting the generality of the foregoing:



8.1.1.1.1      the
Company is a corporation existing under the Canada Business Corporations Act;



8.1.1.1.2      the
Company has the corporate power and authority to carry on its business as now conducted by it and carry on its business as described
in the Final Prospectus and any Amendment, and to execute, deliver and perform its obligations under this Agreement;



8.1.1.1.3      this
Agreement and the performance of the Company’s obligations hereunder, have been duly authorized by all necessary corporate
action on the part of the Company;



8.1.1.1.4      this
Agreement has been duly executed and delivered by the Company, and constitutes a valid and legally binding obligation of the Company
enforceable against the Company in accordance with its terms;



8.1.1.1.5      the
execution and delivery by the Company of this Agreement, and the performance by the Company of its obligations hereunder does not
contravene: (i) the articles or bylaws of the Company; or (ii) any resolution of the directors or shareholders of the Company;



8.1.1.1.6      as
to the authorized capital of the Company as of the close of business on the business day immediately preceding the Closing Date;



8.1.1.1.7      the
Company is a reporting issuer in each of the Qualifying Jurisdictions;



8.1.1.1.8      the
Initial Preliminary Prospectus, Amended and Restated Preliminary Prospectus, Final Prospectus and any Amendment, and the filing
thereof with the Securities Commissions, have been duly authorized by and on behalf of the Company, and each of the Initial Preliminary
Prospectus, Amended and Restated Preliminary Prospectus, Final Prospectus and any Amendment has been duly executed pursuant to
such authorization by and on behalf of the Company;



23







8.1.1.1.9      the
statements as to the qualification of the Offered Securities as investments under the heading “Eligibility for Investment”
in the Final Prospectus and any Amendment are accurate in all material respects, subject to the limitations and qualifications
stated or referred to in the Final Prospectus and any Amendment;



8.1.1.1.10    the
statements as to matters of the federal laws of Canada set out in the Final Prospectus and any Amendment under the heading “Material
Canadian Federal Income Tax Consequences” are accurate in all material respects, subject to the limitations and qualifications
stated or referred to in the Final Prospectus and any Amendment;



8.1.1.1.11    all
necessary documents have been filed, all necessary proceedings have been taken and all necessary legal requirements have been fulfilled
by or under the laws of the Qualifying Jurisdictions to qualify the Offered Securities for sale to the public in each of such Qualifying
Jurisdictions through investment dealers or brokers registered under the applicable laws of such Qualifying Jurisdictions who have
complied with the relevant provisions of such law and the terms of such registrations;



8.1.1.1.12    the
Stock Exchange has conditionally approved the listing of the Offered Shares, subject only to the fulfillment of Standard Listing
Conditions;



8.1.1.1.13    the
issuance of the Offered Shares has been duly authorized by the Company and, upon receipt by the Company of consideration therefor
in accordance with the terms of this Agreement, the Offered Shares will be validly issued, fully-paid and non-assessable common
shares of the Company;



8.1.1.1.14    the
attributes of the Offered Securities conform, in all material respects, with the description thereof contained in the Final Prospectus;
and



8.1.1.1.15    Computershare
Investor Services Inc. has been duly appointed as registrar and transfer agent of the Common Shares.



It is understood
that such counsel may rely on the opinions of local counsel acceptable to them as to matters governed by the laws of jurisdictions
other than Canada and the Provinces of British Columbia, Alberta and Ontario (or alternatively, make arrangements to have such
opinions directly addressed to the Underwriters and counsel to the Underwriters) and may rely, to the extent appropriate in the
circumstances, as to matters of fact, on certificates of an officer of the Company and public officials, as applicable, and letters
from stock exchange representatives and transfer agents;



24







8.1.1.2        in
the event that a United States Purchaser has agreed to purchase Offered Securities, a favourable legal opinion, dated the Closing
Date or Over-Allotment Closing Time, as applicable, from the Company’s United States counsel, Cooley LLP, that no registration
of the Offered Securities will be required under the U.S. Securities Act in connection with (i) the offer, sale and delivery of
the Offered Securities in the United States or (ii) the initial re-offer and resale of the Offered Securities by the Underwriters
directly, or through the U.S. Affiliates, as applicable, in the United States, provided, in each case, that the sale of Offered
Securities in the United States is made in accordance with the terms as set out in Annex A;



8.1.1.3        an
opinion from Canadian and U.S. counsel to the Corporation on matters of law pertaining to the patent applications and patents of
the Corporation in the form substantially delivered to the Underwriters on the date hereof;



8.1.1.4        a
certificate or certificates, dated the Closing Date and signed by the chief executive officer and the chief financial officer of
the Company, or such other officers of the Company as may be acceptable to the Underwriters, certifying on behalf of the Company,
not in their personal capacity and without personal liability:



| | (i) | that the Company has complied with all terms and conditions of this Agreement to be complied with
thereby at or prior to the Closing Time;
| | --- | ------------------------------------------------------------------------------------------------------------------------------------------



| | (ii) | that the representations and warranties of the Company contained herein are true and correct as
of the Closing Time with the same force and effect as if made at and as of the Closing Time after giving effect to the transactions
contemplated hereby;
| | ---- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | (iii) | that no order, ruling or determination having the effect of ceasing or suspending trading in the
Offered Securities has been issued and no proceedings for such purpose are pending or, to the best of the knowledge, information
and belief of the persons signing such certificate, are contemplated or threatened;
| | ----- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | (iv) | since the respective dates of the Final Prospectus and any Amendment there has been no material
adverse change, financial or otherwise, in the business, affairs, operations, assets, liabilities (contingent or otherwise), capital
or prospects of the Company Entities (taken as a whole), or any development involving a prospective material adverse change, financial
or otherwise, in the business, affairs, operations, assets, liabilities (contingent or otherwise) or capital of the Company Entities
(taken as a whole), from that disclosed in the Final Prospectus or any Amendment, as the case may be (as they existed at the time
of filing); and
| | ---- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | (v) | since the date of this Agreement, no transaction or agreement has been entered into by any Company
Entity which is material to the Company Entities (taken as a whole) other than as described in the Final Prospectus or any Amendment;
| | --- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



25







and such statements
shall be true in fact;



8.1.1.5        the
executed lock-up agreements of each of the Company’s directors and senior officers contemplated by paragraph 3.5 hereof;



8.1.1.6        the
comfort letter from the Auditors required to be delivered at the Closing Time pursuant to paragraph 5.3;



8.1.1.7        evidence
satisfactory to the Underwriters that the Company has obtained all necessary approvals for the listing of the Offered Securities
on the Stock Exchange subject only to the Standard Listing Conditions;



8.1.1.8        evidence
satisfactory to the Underwriters that the Board of Directors has authorized and approved the issuance of the Offered Securities
and all matters relating thereto;



8.1.1.9        one
or more global certificates representing the Offered Shares registered in the name of CDS & Co. or its nominee, or in such
name or names as the Lead Underwriter may direct (or its equivalent in the non-certificated inventory system of the Company’s
registrar and transfer agent), against payment to the Company, or as the Company may direct, of the Purchase Price net of the Underwriting
Fee by wire transfer payable in Toronto; and



8.1.1.10      such
other certificates and other documents as the Underwriters may require, acting reasonably, and as are customary in a transaction
of this nature;



all in form and substance satisfactory
to the Underwriters, acting reasonably; and



| | 8.1.2 | the Underwriters not having previously terminated their obligations pursuant to paragraph 11
of this Agreement.
| | ----- | ---------------------------------------------------------------------------------------------------------------



| | 8.2 | It shall be a condition precedent to the Company’s obligations to issue and sell the Offered
Shares that:
| | --- | ---------------------------------------------------------------------------------------------------------



| | 8.2.1 | the Underwriters shall have delivered or caused to be delivered to the Company a wire transfer
representing the Purchase Price payable by the Underwriters for the Offered Shares, less the Underwriting Fee; and
| | ----- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 8.2.2 | the Underwriters shall have complied with the covenants and satisfied all terms and conditions
herein contained to be complied with and satisfied by them at or prior to the Closing Time.
| | ----- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



26







| | 8.3 | The Over-Allotment Option shall be exercisable, in whole or in part, at any time and from time
to time, until the Over-Allotment Expiry Date. If the Lead Underwriter, on behalf of the Underwriters, elects to exercise the Over-Allotment
Option, the Lead Underwriter shall deliver written notice to the Company confirming the number of Over-Allotment Shares in respect
of which the Over-Allotment Option is being exercised. Upon exercise of the Over-Allotment Option, the Company shall become obligated,
on the Over-Allotment Option Closing Time, to issue and sell and the Underwriters shall become severally obligated to purchase
the total number of the Over-Allotment Shares as to which the Underwriters are exercising the Over-Allotment Option in accordance
with their respective percentages set out in paragraph 13 hereof. The Over-Allotment Option closing time (the “Over-Allotment
Closing Time”) shall be determined by the Lead Underwriter on behalf of the Underwriters but shall not be earlier than two
complete Business Days or later than five Business Days after the exercise of the Over-Allotment Option and, in any event, shall
not be earlier than the Closing Date.
| | --- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



If the Over-Allotment Option is
exercised as to all or any portion of the Over-Allotment Shares, one or more global certificates for such Over-Allotment Shares
(or its equivalent in the non-certificated inventory system of the Company’s registrar and transfer agent), and payment therefor,
shall be delivered at the Over-Allotment Closing Time in the manner, and upon the terms and conditions, set forth in paragraphs
8.1 and 8.2, except that reference therein to the Offered Shares and Closing Time shall be deemed, for the purposes of this paragraph
8.3, to refer to such Over-Allotment Shares and Over-Allotment Closing Time, respectively, and the amount payable by the Underwriters
to the Company in respect of the exercise of the Over-Allotment Option shall be equal to the sum of (i) the number of Over-Allotment
Shares in respect of which the Over-Allotment Option is exercised multiplied by $0.50 and the underwriting fee payable by the Company
to the Underwriters in respect of such exercise shall be equal to 7.0% of the aggregate price in respect of such Over-Allotment
Shares, plus applicable taxes, if any (such fee, also the “Underwriting Fee”). The Lead Underwriter shall be entitled
to receive, out of the Underwriting Fee payable pursuant to this paragraph 8.3, the Work Fee. The allocation of the remainder of
the Underwriting Fee payable pursuant to this paragraph 8.3 (after application of the Work Fee) among the Underwriters will be
in the respective percentages set forth in paragraph 13 hereof.



If the Over-Allotment Option is
exercised, the obligations of the Underwriters to purchase the Over-Allotment Shares shall be conditional on the delivery by the
Company of the certificate referred to in paragraph 8.1.1.4 as of the Over-Allotment Closing Time as if references therein to Closing
Time were references to Over-Allotment Closing Time, the comfort letter from the Auditors required to be delivered at the Over-Allotment
Closing Time pursuant to paragraph 5.3 and such other certificates, opinions, agreements, materials or other documents in
form and substance satisfactory to the Underwriters as they may reasonably request.



The obligation of the Underwriters
to close the exercise of the Over-Allotment Option at the Over-Allotment Closing Time shall be conditional on the Underwriters
not having previously terminated their obligations pursuant to paragraph 11 this Agreement, with reference therein to “Closing
Time” being deemed, for the purposes hereof, to refer to the Over-Allotment Closing Time.



27







| | 9. | Indemnity
| | -- | ---------



| | 9.1 | The Company (the “Indemnifying Party”) shall indemnify and hold harmless each of the
Underwriters and their respective subsidiaries and affiliates, and each of their respective directors, officers, employees, shareholders,
partners, “controlling persons” (within the meaning of Section 15 of the U.S. Securities Act or Section 20 of the U.S.
Exchange Act) and agents (collectively, the “Indemnified Parties”) from and against all Claims to which any of the
Indemnified Parties may become subject or otherwise involved in any capacity insofar as the Claims arise out of, result from, are
based upon, or arise directly or indirectly by reason of:
| | --- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 9.1.1 | any information or statement (except any information or statement relating to Underwriters’
Disclosure) contained in the Initial Preliminary Prospectus, Amended and Restated Preliminary Prospectus, Final Prospectus, the
U.S. Placement Memorandum or any Amendment, being or being alleged to be an untrue statement, omission or misrepresentation; or
| | ----- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 9.1.2 | any order made or any inquiry, investigation or proceeding announced, instituted or threatened
by any court, securities regulatory authority, stock exchange or by any other competent authority, based upon any untrue statement,
omission or misrepresentation or alleged untrue statement, omission or misrepresentation (except a statement, omission or misrepresentation
relating solely to Underwriters’ Disclosure) in the Initial Preliminary Prospectus, Amended and Restated Preliminary Prospectus,
Final Prospectus, the U.S. Placement Memorandum or any Amendment (except any document or material delivered or filed solely by
the Underwriters) preventing or restricting the trading in or the sale or distribution of the Offered Securities in any of the
Qualifying Jurisdictions or the United States; or
| | ----- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 9.1.3 | any breach or default under any representation, warranty, covenant or agreement of the Company
in this Agreement or any other documents, materials, instruments or certificates to be delivered pursuant hereto or the failure
thereby to comply with any of its obligations hereunder or thereunder; or
| | ----- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 9.1.4 | the Company failing to comply with any requirement of any Securities Laws or U.S. Securities Laws
relating to the offering of the Offered Securities.
| | ----- | -----------------------------------------------------------------------------------------------------------------------------------------------------



28







| | 9.2 | If any Claim contemplated by this paragraph 9 shall be asserted against any of the Indemnified
Parties, or if any potential Claim contemplated by this paragraph 9 shall come to the knowledge of any of the Indemnified Parties,
the Indemnified Party concerned shall notify the Indemnifying Party, as soon as practicable, of the nature of such Claim (provided
that any failure or delay to so notify shall not, except (and only) to the extent of actual material prejudice to the Indemnifying
Party therefrom, affect the Indemnifying Party’s liability under this paragraph 9), and the Indemnifying Party shall, subject
as hereinafter provided, be entitled (but not required) to assume the defence on behalf of the Indemnified Party of any suit brought
to enforce such Claim. Any such defence shall be through legal counsel acceptable to the Indemnified Party, and the Indemnifying
Party shall pay the fees and disbursements of such counsel relating to such matter, and no admission of liability or settlement
shall be made by the Indemnifying Party without, in each case, the prior written consent of the Indemnified Party, such consent
not to be unreasonably withheld. Without limiting the generality of the foregoing, the Indemnifying Party shall not, without the
Underwriters’ prior written consent, settle, compromise, consent to the entry of any judgment in or otherwise seek to terminate
any Claim in respect of which indemnification may be sought hereunder (whether or not any Indemnified Party is a party thereto)
unless such settlement, compromise, consent or termination includes an unconditional release of all Indemnified Parties from any
liabilities arising out of such Claim without any admission of negligence, misconduct, liability or responsibility by any Indemnified
Party. An Indemnified Party shall have the right to employ separate counsel in any such suit and participate in the defence thereof
but the fees and expenses of such counsel shall be at the expense of the Indemnified Party unless: (i) the Indemnifying Party
fails to assume the defence of such suit on behalf of the Indemnified Party within 14 days of receiving notice of such suit or
having assumed such defense, fails to pursue it; (ii) the employment of such counsel has been authorized by the Indemnifying
Party; or (iii) the named parties to any such suit (including any added or third parties) include both the Indemnified Party
and the Indemnifying Party and the Indemnified Party shall have been advised in writing by counsel that there may be one or more
legal defences available to the Indemnified Party which are different from or in addition to those available to the Indemnifying
Party or the Indemnified Party is advised by counsel that there is an actual or potential conflict in the Indemnifying Party’s
and its interests (in each of which cases the Indemnifying Party shall not have the right to assume the defence of such suit on
behalf of the Indemnified Party, the Indemnified Party shall be required to keep the Indemnifying Party apprised of the developments
of the Claim, including providing copies of any material documents related thereto to the Indemnifying Party and the Indemnifying
Party shall be liable to pay the reasonable fees and expenses of the counsel for the Indemnified Party). No admission of liability
or settlement may be made by an Indemnified Party without, in each case, the prior written consent of the Indemnifying Party, such
consent not to be unreasonably withheld. It is understood that the Indemnifying Party shall, in connection with any one Claim or
separate but substantially similar or related Claims in the same jurisdiction arising out of the same general allegations or circumstances,
be liable for the fees and expenses of only one separate law firm at any time for all Indemnified Parties not having actual or
potential differing interests. It is the intention of the Indemnifying Party to constitute the Underwriters as trustees for the
Underwriters’ subsidiaries and affiliates and their respective directors, officers, employees, shareholders, partners, controlling
persons and agents of the covenants of the Indemnifying Party under this paragraph 9 and the Underwriters agree to accept
such trust and to hold and enforce such covenants on behalf of such persons.
| | --- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 9.3 | The Indemnifying Party agrees to reimburse the Underwriters for the time spent by the Underwriters’
personnel in connection with any Claim contemplated by paragraph 9.1 at their normal per diem rates. The Indemnifying Party also
agrees that if any Claim contemplated by paragraph 9.1 is brought against, or an investigation commenced in respect of, the Indemnifying
Party or the Indemnifying Party and the Indemnified Party and personnel of the Underwriters will be required to testify, participate
or respond in respect of or in connection with this Agreement, the Underwriters will, acting reasonably have the right to employ
their own counsel in connection therewith and the Indemnifying Party will reimburse the Underwriters for the time spent by their
personnel in connection therewith at their normal per diem rates together with such reasonable disbursements and out-of-pocket
expenses as may be reasonably incurred, including reasonable fees and disbursements of the Underwriters’ counsel.
| | --- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



29







| | 9.4 | If for any reason the indemnification provided for in paragraph 9.1 is unavailable or unenforceable,
in whole or in part, to or by an Indemnified Party in respect of any losses, claims, damages, liabilities, costs or expenses (or
claims in respect thereof) for which indemnity is provided in paragraph 9.1, and subject to the restrictions and limitations referred
to therein, the Indemnifying Party and each affected Underwriter shall contribute to the aggregate amount paid or payable (or,
if such indemnity is unavailable only in respect of a portion of the amount so paid or payable, such portion of the amount so paid
or payable) by such Underwriters as a result of such losses (other than losses of profits in connection with the distribution of
the Offered Securities), claims, damages, liabilities, costs or expenses (or claims in respect thereof) in such proportion as is
appropriate to reflect the relative benefits received by the Indemnifying Party on the one hand and the Underwriters on the other
hand from the sale of the Offered Securities as well as their relative fault; provided, however, that no Underwriter shall in any
event be liable to contribute, in the aggregate, any amount in excess of that Underwriter’s portion of the Underwriting Fee
actually received under this Agreement.
| | --- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



The relative benefits received
by the Indemnifying Party on the one hand and the Indemnified Parties on the other hand shall be deemed to be in the proportion
that the total proceeds received from the sale of the Offered Securities (net of the Underwriting Fee (or any portion thereof)
actually received) is to the Underwriting Fee (or any portion thereof) actually received. The amount paid or payable by an Indemnified
Party as a result of such losses, claims, damages, liabilities, costs or expenses (or claims in respect thereof) referred to above
shall be deemed to include any reasonable legal or other expenses incurred by such Indemnified Party in connection with investigating
or defending any such losses, claims, damages, liabilities, costs or reasonable expenses (or claims in respect thereof), whether
or not resulting in any such claim.



| | 9.5 | The Underwriters shall cease to be entitled to the rights of indemnity and contribution contained
in this paragraph 9 and shall promptly reimburse any funds advanced by the Indemnifying Party pursuant to this paragraph 9:
| | --- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 9.5.1 | if the Company has complied with the provisions of paragraph 3.1.5 and the person asserting
any Claim for which indemnity would otherwise be available was not delivered a copy of the Final Prospectus or was not provided
with a copy of any Amendment which corrects any misrepresentation contained in the Final Prospectus which is the basis for such
Claim and which Final Prospectus or Amendment is required under Securities Laws to be delivered to such person by the Underwriters
or members of any Selling Firm; and
| | ----- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 9.5.2 | if and to the extent that a court of competent jurisdiction in a final judgment that has become
non-appealable or a governmental authority in a final ruling from which no appeal can be made shall determine that a Claim to which
an Indemnified Party may be subject has resulted from the gross negligence or willful misconduct of the Indemnified Party (provided
that for greater certainty, an Underwriter’s failure to conduct such reasonable investigations so as to provide reasonable
grounds for a belief that the Amended and Restated Preliminary Prospectus, Final Prospectus or any Amendment contained no misrepresentation
(or, colloquially, to permit the Underwriter to sustain a “due diligence defense” under Securities Laws) shall not
automatically be deemed to constitute “gross negligence” or “willful misconduct” for purposes of this paragraph 9.5.2
or otherwise automatically be deemed to disentitle an Indemnified Party from claiming indemnification or contribution).
| | ----- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



30







| | 9.6 | The Indemnified Parties shall be indemnified by the Indemnifying Party to the extent and manner
as set out herein. Such indemnity shall be in addition to, and not in derogation or substitution for, any other liability that
any party may have, or any right that any of the Indemnified Parties may have, apart from that indemnity. The rights of contribution
provided in this paragraph 9 are in addition to and not in derogation or substitution of any other right to contribution which
the Indemnified Parties may have by statute or otherwise at law.
| | --- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 9.7 | The Indemnifying Party hereby waives any right it may have of first requiring an Indemnified Party
to proceed against, enforce any other right, power, remedy or security or claim payment from, any other person before claiming
against it.
| | --- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 9.8 | Notwithstanding any other section or provision contained herein, the rights to indemnity and contribution
contained in this paragraph 9 shall survive the Closing Time and shall, subject to Section 16, continue in full force and
effect unaffected by any disposition by the Underwriters of any or all of the Offered Securities.
| | --- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 10. | Expenses
| | --- | --------



| | 10.1 | Whether or not the transactions herein contemplated shall be completed, all reasonable expenses
of or incidental to the Offering and the transactions herein contemplated including, without limitation: listing fees, expenses
payable in connection with the qualification of the distribution of the Offered Securities, the fees and expenses of counsel for
the Company, all fees and expenses of local counsel, all fees and expenses of the Auditors and Underwriters (including (i) consultant
fees and (ii) fees of Underwriters’ legal counsel (up to a maximum of $130,000, plus disbursements and applicable taxes,
subject to be increased upon the Company’s written consent, which consent shall not be unreasonably withheld), all reasonable
costs and out of pocket expenses incurred in the marketing of the Offered Securities (including travel), all costs relating to
roadshows, meetings and the preparation of audio-visual and other meeting materials and all costs incurred in connection with preparing,
printing and providing commercial copies of the Initial Preliminary Prospectus, Amended and Restated Preliminary Prospectus, the
Final Prospectus, the U.S. Placement Memorandum, any Amendment, marketing materials, other documents and certificates representing
the Offered Securities, and all applicable taxes, shall be borne by and be for the account of the Company.
| | ---- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 11. | Termination
| | --- | -----------



| | 11.1 | In addition to any other remedies which may be available to the Underwriters, an Underwriter shall
be entitled, at its option, to terminate and cancel, without any liability on the Underwriter’s part, that Underwriter’s
obligations under this Agreement if, prior to the Closing Time:
| | ---- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



31







| | 11.1.1 | any order to cease or suspend trading in any securities of the Company, or prohibiting or restricting
the distribution of the Offered Shares is made, or any proceeding is announced or commenced for the making of any such order, by
any securities regulatory authority, any stock exchange or by any other competent authority, and has not been rescinded, revoked
or withdrawn;
| | ------ | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 11.1.2 | any inquiry, action, suit, investigation or other proceeding (whether formal or informal) is instituted,
announced or threatened or any order is issued by any Governmental Authority or otherwise (other than an inquiry, investigation,
proceeding or order based upon the activities or alleged activities of the Underwriters or the Selling Firms), or there is any
change of law, or the interpretation or administration thereof, which in the reasonable opinion of the Underwriter operates to
prevent or restrict the trading in the Common Shares or the distribution of the Offered Shares or which in the reasonable opinion
of the Underwriter, acting in good faith, could be expected to have a material adverse effect on the market price or value of the
Offered Shares or Common Shares, by giving the Company and, if applicable, the Lead Underwriter written notice to that effect not
later than the Closing Time;
| | ------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 11.1.3 | there shall occur any material change in the business, financial condition, assets, liabilities
(contingent or otherwise), results of operations or prospects of the Company Entities (taken as a whole) or any change in any material
fact contained or referred to in the Final Prospectus or any Amendment, or there shall exist or be discovered by any Underwriter
any material fact which is, or may be, of such a nature as to render the Final Prospectus or any Amendment, untrue, false or misleading
in a material respect or result in a misrepresentation (other than a change or fact related solely to the Underwriters or the Selling
Firms), which in the reasonable opinion of the Underwriter could be expected to have a material adverse effect on the market price
or value of the Offered Shares or Common Shares, by giving the Company and, if applicable, the Lead Underwriter written notice
to that effect not later than the Closing Time;
| | ------ | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 11.1.4 | there should develop, occur or come into effect or existence any event, action, state, condition
or occurrence of national or international consequence, acts of hostilities or escalation thereof or other calamity or crisis or
any change or development involving a prospective change in national or international political, financial or economic conditions
or any action, law, regulation or inquiry which, in the reasonable opinion of the Underwriter, (i) materially adversely affects
or involves, or may materially adversely affect or involve, the financial markets in Canada or the United States either in general,
or solely in respect of the biotechnology and healthcare sector, or the business, operations or affairs of the Company Entities
(taken as a whole), or the market price or value of the Offered Shares or Common Shares or (ii) results in the Offered Shares to
not be marketed profitably, by giving the Company and, if applicable, the Lead Underwriter written notice to that effect not later
than the Closing Time; or
| | ------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 11.1.5 | the Passport Decision Document for the Final Prospectus has not been received by the Qualification
Deadline.
| | ------ | ------------------------------------------------------------------------------------------------------------



32







If an Underwriter terminates its
obligations hereunder pursuant to this paragraph 11, the Company’s liability hereunder to that Underwriter shall be
limited to the Company’s obligations under paragraph 9 and payment of expenses referred to in paragraph 10 hereof.



| | 12. | Reliance on Lead Underwriter, etc.
| | --- | ----------------------------------



All steps or other actions
which must or may be taken by the Underwriters in connection with this Agreement shall be taken by the Lead Underwriter, with the
exception of the matters contemplated by paragraphs 2.1.4, 9, 11, 13 and 14, on the Underwriters’ behalf, and the execution
of this offer by the Underwriters shall constitute the authority of the Company for accepting notification of any such steps or
other actions from the Lead Underwriter.



| | 13. | Underwriters’ Obligation to Purchase Offered Securities
| | --- | -------------------------------------------------------



| | 13.1 | The Underwriters’ obligation to purchase the Offered Securities at the Closing Time or Over-Allotment
Closing Time, as applicable, shall be several and not joint, and the Underwriters’ respective obligations in this respect
shall be as to the following percentages of the aggregate amount of Offered Securities to be purchased at that time:
| | ---- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



|Underwriter                  |  | Percentage |     
|---------------------------- |  | ---------- | ----
|RBC Dominion Securities Inc. |  |            | 55  
|Roth Capital Partners, LLC   |  |            | 27.5
|Cormark Securities Inc.      |  |            | 17.5



| | 13.2 | Except as set out below, if one or more of the Underwriters fails to purchase (each, a “Refusing
Underwriter”) its or their applicable percentages of the aggregate amount of the Offered Securities at the Closing Time (the
“Defaulted Shares”), the other Underwriter or Underwriters shall have the right, but shall not be obligated, to purchase
on a pro rata basis (or in such other proportion as the remaining Underwriters may mutually agree) all, but not less than all,
of the Defaulted Shares which would otherwise have been purchased by the Refusing Underwriter(s). Nothing in this paragraph 13.2
shall oblige the Company to sell to any or all of the Underwriters less than all of the aggregate amount of the Offered Securities
or shall relieve any of the Underwriters in default hereunder from liability to the Company.
| | ---- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 14. | Conditions
| | --- | ----------



All of the terms and
conditions contained in this Agreement to be satisfied by the Company prior to the Closing Time or Over-Allotment Closing Time,
as applicable, shall be construed as conditions, and any breach or failure by the Company to comply with any of such terms and
conditions shall entitle any Underwriter to terminate its obligations hereunder by written notice to that effect given to the Company
prior to the Closing Time or Over-Allotment Closing Time, as applicable. It is understood and agreed that the Underwriters may
waive in whole or in part, or extend the time for compliance with, any of such terms and conditions without prejudice to their
rights in respect of any such terms and conditions or any other or subsequent breach or non-compliance; provided, however, that
to be binding, any such waiver or extension must be in writing and signed by all the Underwriters. If an Underwriter elects to
terminate its obligations hereunder the obligations of the Company hereunder shall be limited to the indemnity referred to in paragraph 9
hereof and the payment of expenses referred to in paragraph 10 hereof.



33







| | 15. | Survival
| | --- | --------



All warranties, representations,
covenants and agreements of the Company herein contained (including its obligations under paragraphs 9 and 10 shall survive
the purchase by the Underwriters of the Offered Securities and shall continue in full force and effect for the period hereinafter
described, regardless of any investigation which the Underwriters may carry out or which may be carried out on behalf of the Underwriters
or otherwise and notwithstanding any subsequent disposition by the Underwriters of the Offered Securities. Such warranties, representations,
covenants and agreements of the Company shall survive for such maximum period of time as the Underwriters may be entitled to commence
an action, or exercise a right of rescission, with respect to a misrepresentation contained in the Final Prospectus or an Amendment
or either of them, pursuant to applicable Securities Laws in any of the Qualifying Jurisdictions (and, for greater certainty, each
of the Indemnified Parties shall be entitled to bring a claim for indemnification pursuant to paragraph 9 hereof within such
period of time). Notwithstanding the foregoing, in the case of any fraud or fraudulent misrepresentation of the Company, the representations,
warranties and covenants of the Company contained in this Agreement or in agreements, certificates or other documents referred
to in this Agreement or delivered pursuant to this Agreement shall survive the purchase and sale of the Offered Securities and
the termination of this Agreement and shall remain in full force and effect indefinitely.



| | 16. | Securities Sales
| | --- | ----------------



The Company will not,
without the prior written consent of the Lead Underwriter, such consent not to be unreasonably withheld, during the period commencing
on the signing of this Agreement and ending 90 days following the Closing Date, (i) offer, pledge, sell, contract to sell any option
or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase or otherwise transfer,
lend or dispose of directly or indirectly, Common Shares or any securities convertible into or exercisable or exchangeable for
Common Shares, or (ii) enter into any swap or other arrangement that transfers, in whole or in part, any of the economic consequences
of ownership of Common Shares or such other securities of the Company, whether any such transaction referred to in clauses (i)
or (ii) of this paragraph is to be settled by delivery of Common Shares or such other securities of the Company, in cash or otherwise,
other than (a) the sale of the Offered Securities as contemplated in this Agreement, (b) issuances of Common Shares in connection
with the exercise of obligations outstanding as at the date hereof, (c) issuances under any of the Company’s incentive plans
existing as at the date hereof, (d) issuance of securities as consideration in connection with bona fide arm’s-length acquisitions
or debt financings by the Company, or (e) issuance of securities in connection with any licensing or commercial transaction with
a bona fide third party.



| | 17. | Notice
| | --- | ------



Any notice or other communication
required or permitted to be given hereunder shall be in writing and shall be personally delivered or sent by facsimile on a Business
Day to the following addresses:



34







in the case of the
Company:



2 Meridian Road
Toronto, Ontario
M9W 4Z7



Attention:        Dr.
William Rice

Fax Number:   416-798-2200



with a copy (which shall not constitute
notice) to:



McCarthy Tétrault LLP
1150, rue de Claire Fontaine, 7th Floor

Québec, Québec

G1R 5G4



Attention:        Charles-Antoine Soulière

Facsimile:       418-521-3099



in the case of the
Underwriters:



RBC Dominion Securities Inc.
Royal Bank Plaza, 200 Bay Street
South Tower, 4th Floor
Toronto, Ontario
M5J 2W7



Attention:        Matt
Pittman

Fax Number:   416-842-6678



-and-



Roth Capital Partners, LLC
888 San Clemente Drive
Newport Beach, CA 92660



Attention:        Aaron
M. Gurewitz

Fax Number:   949-720-7227



35







-and-



Cormark Securities Inc.
Royal Bank Plaza

South Tower, Suite 2800

200 Bay Street

Toronto, Ontario M5J 2J2

Canada



Attention:        Jeff
Kennedy

Fax Number:   416-943-6499



with a copy (which shall not constitute
notice) to:



Torys LLP
79 Wellington Street West, Suite 3000
Box 270, TD Centre
Toronto, Ontario
M5K 1N2



Attention:        Cheryl
Reicin

Fax Number:   416-865-7380



The Company or any of
the Underwriters may change its address by notice given in the manner aforesaid. Any such notice or other communication shall be
deemed to have been given on the day on which it was delivered or sent by facsimile if received during normal business hours; otherwise
it shall be deemed to have been received by 9:00 a.m. on the next Business Day.



| | 18. | Time of Essence
| | --- | ---------------



Time shall be of the
essence of this Agreement.



| | 19. | Governing Law
| | --- | -------------



This Agreement shall
be governed by and construed in accordance with the laws of the Province of Ontario and the laws of Canada applicable therein and
the courts of Ontario shall have non-exclusive jurisdiction over any dispute hereunder.



| | 20. | Counterparts
| | --- | ------------



This Agreement may be
executed in several counterparts, including by facsimile, each of which when so executed shall be deemed to be an original and
such counterparts together shall constitute one and the same instrument.



| | 21. | Publicity
| | --- | ---------



Neither the Company nor
the Underwriters shall make any public announcement concerning the appointment of the Underwriters or the offering without the
consent of the other parties, acting reasonably, and any public announcements shall be made in compliance with applicable Securities
Laws. After completion of the Offering, the Underwriters shall be entitled to place advertisements in financial and other newspapers
and journals at their own expense describing their services hereunder.



36







| | 22. | Acknowledgement by the Company
| | --- | ------------------------------



The Company hereby acknowledges
that (i) the purchase and sale of the Offered Securities pursuant to this Agreement, including the determination of the Offering
Price, is an arm’s-length commercial transaction between the Company, on the one hand, and each of the Underwriters and any
affiliate through which it may be acting, on the other, (ii) each of the Underwriters is acting as principal and not as an agent
or fiduciary of the Company, (iii) the engagement by the Company of each of the Underwriters in connection with the offering and
sale of the Offered Securities and the process leading up to the offering and sale thereof is as independent contractors and not
in any other capacity; (iv) the Underwriters and their respective affiliates may be engaged in a broad range of transactions that
involve interests that differ from those of the Company; and (v) the Underwriters have not provided any legal, accounting, regulatory
or tax advice with respect to the Offering and the Company has consulted its own legal, accounting, regulatory and tax advisors
to the extent it deemed appropriate. Furthermore, the Company agrees that it is solely responsible for making its own judgments
in connection with the offering and sale of the Offered Securities (irrespective of whether any of the Underwriters has advised
or is currently advising the Company on related or other matters) and no Underwriter has any obligation to the Company with respect
to the Offering except the obligations expressly set forth in this Agreement. The Company agrees that it will not claim that the
Underwriters have rendered advisory services of any nature or respect, or owe an agency, fiduciary or similar duty to the Company,
in connection with the offering and sale of the Offered Securities.



| | 23. | Underwriters’ Activities
| | --- | ------------------------



The Company acknowledges
that the Underwriters and their affiliates carry on a range of businesses, including providing banking, credit derivative, hedging
and foreign exchange products and services, institutional and retail brokerage, investment advisory, research, investment management,
securities lending and custodial services to clients (including companies that are or may be involved in the transactions contemplated
in this Agreement or are affiliated with the Company) and trading in financial products as agent or principal. It is possible that
the Underwriters and other entities in their respective groups that carry on those businesses may hold long or short positions,
and may trade or otherwise effect or recommend transactions, in securities of companies or other entities (including the Company),
which are or may be involved in the transactions contemplated in this Agreement or are affiliated with the Company and effect transactions
in those securities for their own account or for the account of their respective clients. The Company agrees that these divisions
and entities may hold such positions and effect such transactions without regard to the Company’s interest under this Agreement.



| | 24. | Entire Agreement
| | --- | ----------------



Unless expressly otherwise
agreed to in writing between the applicable parties, this Agreement, including Annex A hereto, constitutes the entire agreement
among the Underwriters and the Company relating to the subject matter of this Agreement and supersedes all prior agreements between
those parties with respect to their respective rights and obligations in respect of the transactions contemplated under this Agreement.



37







| | 25. | U.S. Offers
| | --- | -----------



| | 25.1 | The Underwriters make the representations, warranties, covenants and agreements applicable to them
in Annex A hereto and agree, on behalf of themselves and their U.S. Affiliates, if applicable, for the benefit of the Company,
to comply with the U.S. selling restrictions imposed by the laws of the United States and set forth in Annex A hereto. Notwithstanding
the foregoing provisions of this section, no Underwriter or its U.S. Affiliate will be liable to the Company under this section
or Annex A hereto with respect to a violation by another Underwriter or its U.S. Affiliate of the provisions of this section or
Annex A hereto if the former Underwriter or its U.S. Affiliate is not itself also in violation.
| | ---- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 25.2 | The Company makes the representations, warranties, covenants and agreements applicable to it in
Annex A hereto.
| | ---- | ---------------------------------------------------------------------------------------------------------------



[Remainder of page
intentionally left blank. Signature pages follow.]



38







If the foregoing is in
accordance with your understanding and is agreed to by you, please confirm your acceptance by signing this letter at the place
indicated and returning a copy to the Lead Underwriter on behalf of the Underwriters.



| | Yours very truly,           
| | ----------------------------
| | RBC DOMINION SECURITIES INC.
| |                             
| | By:                         
| | Name:                       
| | Title:                      
| |                             
| | ROTH CAPITAL PARTNERS, LLC  
| |                             
| | By:                         
| | Name:                       
| | Title:                      



| | CORMARK SECURITIES INC.
| | -----------------------
| |                        
| | By:                    
| | Name:                  
| | Title:                 



39







Accepted and agreed to as of March 27,
2014.



LORUS THERAPEUTICS INC.



|By:    | (signed) Gregory K. Chow
|------ | ------------------------
|Name:  | Gregory K. Chow         
|Title: | Chief Financial Officer 



I have authority to bind the Company.



40







Schedule A



FORM OF LOCK-UP AGREEMENT



RBC Dominion Securities
Inc., as representative of the several Underwriters party to the Underwriting Agreement referred to below

Royal Bank Plaza, 200 Bay Street
South Tower, 4th Floor
Toronto, Ontario
M5J 2W7



Re:	Lorus Therapeutics Inc. –
Public Offering



Ladies and Gentlemen:



The undersigned understands
that you, as representative of the several Underwriters, have entered into an Underwriting Agreement (the “Underwriting
Agreement”) with Lorus Therapeutics Inc., a Canadian corporation (the “Company”), providing for the
public offering (the “Public Offering”) by the several Underwriters (the “Underwriters”),
of common shares of the Company (the “Securities”). Capitalized terms used herein and not otherwise defined
shall have the meanings set forth in the Underwriting Agreement.



In consideration of
the Underwriters’ agreement to purchase and make the Public Offering of the Securities, and for other good and valuable consideration
receipt of which is hereby acknowledged, the undersigned hereby agrees that, without the prior written consent of RBC Dominion
Securities Inc. (which consent shall not be unreasonably withheld), on behalf of the Underwriters, the undersigned will not, whether
for his or her own account or for the account of another, and will cause any spouse, immediate family member of the undersigned
or immediate family member of the spouse living in the undersigned’s household, or any trust of which any of the foregoing
individuals are beneficiaries, to not in any manner, for a period commencing on the date hereof and terminating as described below,
during the period ending 90 days after the closing date of the Public Offering:



(1) offer, announce
the intention to sell, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell,
grant any option, right or warrant to purchase, or otherwise transfer or dispose of, directly or indirectly, any common shares
of the Company (the “Common Shares”) or any securities convertible into or exercisable or exchangeable for Common
Shares (including, without limitation, Common Shares which may be deemed to be beneficially owned by the undersigned in accordance
with Canadian securities laws and securities which may be issued upon exercise of a stock option or warrant); or



(2) enter into any
swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Common Shares;



whether any such transaction
described in clause (1) or (2) above is to be settled by delivery of Common Shares or such other securities, in cash or otherwise,
in each case other than (A) transfers of Common Shares as a bona fide gift or gifts, or (B) transfers of Common Shares pursuant
to a third party take-over bid made to all shareholders of the Company or similar acquisition transaction provided that in the
event that the take-over or acquisition transaction is not completed, any Common Shares shall remain subject to the restrictions
contained in this Letter Agreement; provided that in the case of any transfer or distribution pursuant to clause (A), each
donee shall execute and deliver to RBC Dominion Securities Inc. a lock-up letter in the form of this paragraph.











In furtherance of the
foregoing, the Company and any duly appointed transfer agent for the registration or transfer of the securities described herein
are hereby authorized to decline to make any transfer of securities if such transfer would constitute a violation or breach of
this Letter Agreement.



The undersigned hereby
represents and warrants that the undersigned has full power and authority to enter into this Letter Agreement. All authority herein
conferred or agreed to be conferred and any obligations of the undersigned shall be binding upon the successors, assigns, heirs
or personal representatives of the undersigned.



The undersigned understands
that if the Underwriting Agreement (other than the provisions thereof which survive termination) shall terminate or be terminated
prior to payment for and delivery of the Securities, the undersigned shall be released from, all obligations under this Letter
Agreement. The undersigned understands that the Underwriters are entering into the Underwriting Agreement and proceeding with the
Public Offering in reliance upon this Letter Agreement.



This Letter Agreement
shall be governed by and construed in accordance with the laws of Province of Ontario, without regard to the conflict of laws principles
thereof.



| | Very truly yours,
| | -----------------



2







ANNEX A

TO

UNDERWRITING AGREEMENT



U.S. Selling Restrictions



As used in this Annex
A, the following terms shall have the meanings indicated:



“Directed Selling Efforts”
means “directed selling efforts” as that term is defined in Rule 902 of Regulation S;



“Foreign Issuer”
shall have the meaning ascribed thereto in Rule 902 of Regulation S;



“Foreign Private Issuer”
shall have the meaning ascribed thereto in Rule 405 of the U.S. Securities Act;



“General Solicitation”
and “General Advertising” mean “general solicitation” and “general advertising”, respectively,
as used in Rule 502(c) under the U.S. Securities Act, including advertisements, articles, notices or other communications
published in any newspaper, magazine or similar media or broadcast over radio or television, or any seminar or meeting whose attendees
had been invited by general solicitation or general advertising or in any other manner involving a public offering within the meaning
of Section 4(a)(2) of the U.S. Securities Act;



“Preliminary U.S. Private
Placement Memorandum” means, the preliminary private placement memorandum dated on or about the date of the Amended and
Restated Preliminary Prospectus prepared in accordance with the securities laws of the United States in respect of sales of Offered
Securities to Qualified Institutional Buyers under Rule 144A in the form approved by the Company and the Underwriters, as the foregoing
may be amended;



“Qualified Institutional
Buyer” means a “qualified institutional buyer” as that term is defined in Rule 144A;



“Regulation S”
means Regulation S adopted by the SEC under the U.S. Securities Act;



“Substantial U.S. Market
Interest” means “substantial U.S. market interest” as that term is defined in Rule 902 of Regulation S;



“United States”
means the United States of America, its territories and possessions, any state of the United States, and the District of Columbia;
and



“U.S. Private Placement
Memorandum” means the private placement memorandum dated on or about the date of the Final Prospectus prepared in accordance
with the securities laws of the United States in respect of sales of Offered Securities to Qualified Institutional Buyers under
Rule 144A, in the form approved by the Company and the Underwriters, as the foregoing may be amended.



All other capitalized
terms used but not otherwise defined in this Annex A shall have the meanings assigned to them in the Underwriting Agreement to
which this Annex A is attached.











Representations,
Warranties and Covenants of the Underwriters



Each Underwriter, separately
and not jointly, acknowledges, on behalf of itself and, other than ROTH, its U.S. Affiliates, that the Offered Securities have
not been and will not be registered under the U.S. Securities Act or any state securities laws and may not be offered or sold
to any person within the United States except pursuant to an exemption from the registration requirements of the U.S. Securities Act
and applicable state securities laws. Accordingly, each Underwriter, separately but not jointly, on behalf of itself and, other
than ROTH, its U.S. Affiliates, represents, warrants and covenants to the Company that:



| | 1. | It has not offered and sold, and will not offer and sell (a) any of the Offered Securities
outside of the United States except in an offshore transaction in accordance with Rule 903 of Regulation S or (b) any
of the Offered Securities in the United States except in accordance with Rule 144A as provided below. Accordingly, neither
the Underwriter, its affiliates nor any persons acting on their behalf has engaged or will engage in, has made or will make or
has facilitated or will facilitate the making of (except as permitted below) (i) any offer to sell or any solicitation of
an offer to buy any Offered Securities to any person in the United States; (ii) any sale of Offered Securities to any purchaser
unless, at the time the buy order was or will have been originated, the purchaser was outside the United States, or such Underwriter,
affiliate or person acting on behalf of either reasonably believed that such purchaser was outside the United States; or (iii) any
Directed Selling Efforts, General Solicitation or General Advertising in the United States with respect to the Offered Securities.
| | -- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 2. | All offers and sales of the Offered Securities in the United States will be effected (other than
by ROTH) by or through the U.S. Affiliate of the Underwriter, duly registered under Section 15 the U.S. Exchange Act
and applicable state securities laws (unless exempted from the respective state’s broker-dealer registration requirements),
or otherwise pursuant to Rule 15a-6 under the U.S. Exchange Act and will be effected in accordance with all applicable U.S. broker-dealer
requirements. Each U.S. Affiliate of the Underwriter purchasing Offered Securities in the United States, and shall be on the
date of any sale of the Offered Securities, is a Qualified Institutional Buyer and a member in good standing with FINRA. ROTH is
duly registered under Section 15 of the U.S. Exchange Act and applicable state securities laws (unless exempted from the respective
state’s broker-dealer registration requirements).
| | -- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 3. | Any offer or solicitation of an offer to buy Offered Securities by it or its U.S. Affiliate that
has been made or will be made in the United States and any sale of Offered Securities by it or its U.S. Affiliate in the United
States was or will be made by the Underwriters or their U.S. Affiliates, acting as principals, in accordance with Rule 144A
only to persons they reasonably believe to be Qualified Institutional Buyers in transactions that are exempt from registration
under the U.S. Securities Act and applicable state securities laws. All offers and sales of Offered Securities in the United
States by the Underwriter or its U.S. Affiliate were made and will be made in compliance with all applicable United States federal
and state broker-dealer requirements and all applicable rules of FINRA.
| | -- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 4. | Immediately prior to soliciting such offerees, the Underwriter and its U.S. Affiliate, if
applicable, had reasonable grounds to believe and did believe that each offeree was a Qualified Institutional Buyer.
| | -- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



ANNEX A - Page 2







| | 5. | At closing, it, together with its U.S. Affiliate selling Offered Securities in the United
States, if applicable, will provide a certificate, substantially in the form of Exhibit A to this Annex A relating to the manner
of the offer and sale of the Offered Securities in the United States.
| | -- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 6. | The Underwriter shall inform (and shall cause its U.S. Affiliate to inform, if applicable)
each purchaser to whom it or its U.S. Affiliate sells Offered Securities in the United States that such securities have not
been and will not be registered under the U.S. Securities Act and are being sold to it in reliance on the exemption from registration
under the U.S. Securities Act provided by Rule 144A.
| | -- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7. | The Underwriter shall or shall cause its U.S. Affiliate to deliver a copy of the Preliminary
U.S. Private Placement Memorandum or the U.S. Private Placement Memorandum, to each of its offerees in the United States
and a copy of the U.S. Private Placement Memorandum and any Amendment to each purchaser of the Offered Securities in the United
States at or prior to the time of purchase of Offered Securities.
| | -- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 8. | Neither the Underwriter, its U.S. Affiliate or any person acting on its behalf has taken or will
take, directly or indirectly, any action in violation of Regulation M under the U.S. Exchange Act in connection with the offer
and sale of the Offered Securities.
| | -- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 9. | Prior to the completion of any sale of Offered Securities in the United States, the Underwriter
or its U.S. Affiliate, as applicable, will cause each purchaser purchasing Offered Securities pursuant to Rule 144A (a “U.S.
Purchaser”) to provide to the Underwriter or its U.S. Affiliate, as applicable, a duly executed investment letter in
the form attached to the U.S. Private Placement Memorandum as Exhibit A.
| | -- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



Representations,
Warranties and Covenants of the Company



The Company represents,
warrants, covenants and agrees (provided that for purposes of the following representations, warranties, covenants and agreements
of the Company, none of the Underwriters, their U.S. Affiliates, the Selling Firms or anyone acting on any of their behalf will
be deemed to be an affiliate or a person acting on behalf of the Company) that:



| | 1. | The Company, as of the Closing Date is and as of any Over-Allotment Closing Time will be, a Foreign
Private Issuer and reasonably believed at the commencement of the offering of the Offered Securities that there was, and reasonably
believes there is and will be on the Closing Date and any Additional Closing Time, no Substantial U.S. Market Interest in the Common
Shares.
| | -- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 2. | For so long as the Offered Securities which have been sold in the United States pursuant hereto
are “restricted securities” within the meaning of Rule 144(a)(3) under the U.S. Securities Act, and if the
Company is neither (i) subject to and in compliance with the reporting requirements of Section 13 or 15(d) of the
U.S. Exchange Act nor (ii) exempt from such reporting requirements pursuant to Rule 12g3-2(b) thereunder, the Company
shall provide to any holders of the Offered Securities which have been sold in the United States pursuant hereto, or to any prospective
purchasers of the Offered Securities designated by such holders, upon request of such holders or prospective purchasers, at or
prior to the time of resale, the information required to be provided by Rule 144A(d)(4) under the 1933 Act (so long as
such requirement is necessary in order to permit holders of the Offered Securities to effect resales under Rule 144A).
| | -- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



ANNEX A - Page 3







| | 3. | Neither the Company nor any of its affiliates, nor any person acting on its or their behalf, has
engaged or will engage in any Directed Selling Efforts with respect to the Offered Securities or in any form of General Solicitation
or General Advertising with respect to the Offered Securities in the United States.
| | -- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 4. | The Offered Securities are not, and as of the Time of Closing or any Over-Allotment Closing Time
the Offered Securities will not be, and no securities of the same class as any of the Offered Securities are or will be, (i) listed
on a national securities exchange in the United States registered under Section 6 of the U.S. Exchange Act; (ii) quoted
in an “automated inter-dealer quotation system”, as such term is used in the U.S. Exchange Act; or (iii) convertible
or exchangeable at an effective conversion premium (calculated as specified in paragraph (a)(6) of Rule 144A) or exercisable
at an effective premium (calculated as specified in paragraph (a)(7) of Rule 144A), in each case, of less than ten percent for
securities so listed or quoted.
| | -- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 5. | The Company is not now and as a result of the sale of the Offered Securities contemplated hereby
or the application of the proceeds of the sale of the Offered Securities will not be, an open-ended investment company, unit investment
trust or face-amount certificate company that is or is required to be registered under Section 8 of the Investment Company
Act of 1940, as amended, and the rules and regulations promulgated thereunder.
| | -- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 6. | Neither the Company nor any of its affiliates, nor any person acting on its or their behalf, has
offered or will offer the Offered Securities except through the Underwriters and their U.S. Affiliates pursuant to this Annex A
to the Underwriting Agreement, nor has the same taken or will take any action which would cause any exemptions or exclusions from
the registration requirements of the U.S. Securities Act, including those provided by Rule 903 of Regulation S, Section 4(a)(2)
of the U.S. Securities Act and Rule 144A, to be unavailable for the offer and sale of the Offered Securities.
| | -- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 7. | In connection with offers and sales of Offered Securities outside of the United States, the Company,
its affiliates and any person acting on its or their behalf have complied and will comply with the requirements for an “offshore
transaction” within the meaning of Regulation S.
| | -- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 8. | None of the Company, its affiliates or any person acting on its or their behalf has taken or will
take any action, directly or indirectly, that would constitute a violation of Regulation M under the U.S. Exchange Act in connection
with the offer and sale of the Offered Securities.
| | -- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



ANNEX A - Page 4







Exhibit
A TO Annex A
UNDERWRITERS’ CERTIFICATE



In connection with the
private placement in the United States of the common shares (the “Offered Shares”) of Lorus Therapeutics Inc. (the
“Company”) pursuant to the Underwriting Agreement dated March 27, 2014 among the Company and the Underwriters named
therein (the “Underwriting Agreement”), each of the undersigned does hereby certify as follows:



1.          [Name
of U.S. broker-dealer affiliate] [Roth Capital Partners, LLC]is a duly registered broker or dealer with the United States
Securities and Exchange Commission and is a member of and in good standing with the Financial Industry Regulatory Authority, Inc.
on the date hereof;



2.          each
offeree in the United States to which the undersigned offered Offered Shares was provided with a copy of the Preliminary U.S. Private
Placement Memorandum or the U.S. Private Placement Memorandum and the documents incorporated by reference therein for the offering
of the Offered Shares in the United States and each purchaser of Offered Shares in the United States to which the undersigned
sold Offered Shares was provided with a copy of the U.S. Private Placement Memorandum prior to the time of purchase of Offered
Shares;



3.          immediately
prior to our transmitting such Preliminary U.S. Private Placement Memorandum or U.S. Private Placement Memorandum to such
offerees, we had reasonable grounds to believe and did believe that each such offeree was, and continue to believe that each such
offeree who is purchasing Offered Shares in the United States from us is, a Qualified Institutional Buyer;



4.          each
U.S. Purchaser has provided a duly executed investment letter in the form attached to the U.S. Private Placement Memorandum as
Exhibit A to the Underwriter or its U.S. Affiliate, as applicable;



5.          no
form of General Solicitation (as defined in the Underwriting Agreement) or General Advertising (as defined in the Underwriting
Agreement) was used by us, including advertisements, articles, notices or other communications published in any newspaper, magazine
or similar media or broadcast over radio or television, or any seminar or meeting whose attendees had been invited by general
solicitation or general advertising, in connection with the offer or sale of the Offered Shares in the United States; and



6.          the
offering of the Offered Shares in the United States has been conducted by us in accordance with the terms of the Underwriting
Agreement.



Terms used in this certificate
have the meanings given to them in the Underwriting Agreement unless otherwise defined herein.















DATEDthis n day
of n, 2014.



|[UNDERWRITER] |        | [U.S. BROKER-DEALER AFFILIATE]
|------------- | ------ | ------------------------------
|              |        |                               
|Per:          |        |                               
|              | Name:  |                               
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