Exhibit 10.5

SHAREHOLDER SUPPORT AGREEMENT

This SUPPORT AGREEMENT (this “Agreement”), dated as of December 5, 2018, is made
by and between OncoMed Pharmaceuticals, Inc., a Delaware corporation (the
“Company”), and Invesco Asset Management Limited of Perpetual Park, Perpetual
Park Drive, Henley-on-Thames, Oxfordshire, RG9 1HH, United Kingdom, a private
company limited by shares with company registration number 00 949417 and
registered in England and Wales (“Shareholder”), acting as agent for and on
behalf of Invesco Income Fund (“Fund”).

WHEREAS, in order to induce the Company to enter into an Agreement and Plan of
Merger and Reorganization, dated as of the date hereof (the “Merger Agreement”),
by and among, inter alia, the Company, Mereo BioPharma Group plc, a public
limited company incorporated under the laws of England and Wales (“Milan”) and
Mereo MergerCo One Inc., a Delaware corporation and indirect, wholly-owned
subsidiary of Milan, the Company has requested Shareholder, and Shareholder has
agreed, to enter into this Agreement with respect to all ordinary shares, with
nominal value of £0.003 per ordinary share, of Milan over which the Fund holds
beneficial title (together with any shares of capital stock or voting securities
of Milan hereafter issued to or otherwise acquired or owned by the Shareholder
prior to the termination of this Agreement being referred to herein as the
“Shares”).

NOW, THEREFORE, the parties hereto agree as follows:

ARTICLE 1

VOTING; PROXY APPOINTMENT

Section 1.01. Voting. Shareholder hereby undertakes to procure to vote or
exercise its right to consent with respect to all Shares that Shareholder is
entitled to vote at the time of any vote to (a) approve and adopt the Merger
Agreement, the Merger, the other Contemplated Transactions, and any steps
requested or required of the Shareholder to give effect to the terms of the
Merger Agreement, (b) approve and adopt any “whitewash” resolution sought
pursuant to the U.K. City Code on Takeovers and Mergers (the “Code”), (c)
approve and adopt any amendments to the articles of association of Milan deemed
by the board of directors of Milan to be necessary or desirable in connection
with the Merger (provided any such amendments could not reasonably be considered
to have a material adverse effect on the shareholders of Milan) and (d) approve
and adopt any actions related to the Contemplated Transactions for which the
Milan Board has recommended that the shareholders of Milan vote in favor, in
each case, at any meeting of the shareholders of Milan (including any proposal
to adjourn or postpone such meeting of the shareholders of Milan to a later
date), and at any adjournment or postponement thereof which takes place prior to
the Long Stop Date, at which such Merger Agreement, or such other related
actions, are submitted for the consideration and vote of the shareholders of
Milan. Shareholder hereby agrees to procure that it will not, prior to the Long
Stop Date, vote any Shares in favor of, or consent to, and will vote against and
not consent to, the approval of any (i) Acquisition Proposal with respect to
Milan, (ii) reorganization, recapitalization, liquidation or winding-up of Milan
or any other extraordinary transaction involving Milan, (iii) proposal,
agreement, arrangement or other corporate action that would reasonably be
expected to result in a breach in any respect of any covenant, representation or
warranty or any other obligation or agreement of (A) Milan, as set forth in the
Merger Agreement, or (B) Shareholder, as set forth in this Agreement or
(iv) proposal, agreement, arrangement or other corporate action, the
consummation of which would frustrate the purposes, or prevent, delay or
otherwise adversely affect the consummation, of the transactions contemplated by
the Merger Agreement (in each case other than in respect of any Acquisition
Proposal for 100% of the issued and outstanding share capital of Milan).

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ARTICLE 2

REPRESENTATIONS AND WARRANTIES OF SHAREHOLDER

Shareholder represents and warrants to the Company that:

Section 2.01. Corporate Authorization. The execution, delivery and performance
by Shareholder of this Agreement and the consummation by Shareholder of the
transactions contemplated hereby are within the corporate power and capacity of
Shareholder and have been duly authorized by all necessary corporate action of
the Shareholder. This Agreement has been duly and validly executed and delivered
by Shareholder and constitutes a valid and binding Agreement of Shareholder,
enforceable against Shareholder in accordance with its terms.

Section 2.02. Non-Contravention. The execution, delivery and performance by
Shareholder of this Agreement and the consummation of the transactions
contemplated hereby do not and will not (i) violate the constitutional documents
of Shareholder, (ii) so far as the Shareholder is aware, violate any applicable
law, rule, regulation, judgment, injunction, order or decree, (iii) so far as
the Shareholder is aware, require any consent or other action by any Person
under, constitute a default under, or give rise to any right of termination,
cancellation or acceleration or to a loss of any benefit to which Shareholder is
entitled under any provision of any agreement or other instrument binding on
Shareholder or (iv) result in the imposition of any Encumbrance on any asset of
Shareholder.

 

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Section 2.03. Ownership of Shares. Shareholder confirms that it has investment
discretion in respect of such Shares and has entered into this Agreement on
behalf of the beneficial owner of the Shares, being the Fund, which are legally
held by a nominee, being The Bank of New York (Nominees) Limited (“Nominee”).
None of the Shares is subject to any voting trust or other agreement or
arrangement with respect to the voting of such Shares. Except pursuant to this
Agreement, Shareholder has not entered into any contract granting another Person
any contractual right or obligation to purchase or otherwise acquire any of the
Shares. As of the date hereof, no proxy has been appointed by Shareholder in
respect of any or all of the Shares other than appointments which have expired
or been validly revoked prior to the date hereof (and except for the proxy
voting process the Shareholder has in place with the Nominee).

Section 2.04. Total Shares. As of the date hereof, the Fund and the Nominee
hold, respectively, the beneficial and legal title to the Shares set forth on
the signature page hereto. Except for the Shares set forth on the signature page
hereto, the Fund does not beneficially own any (i) shares or voting securities
of Milan, (ii) securities of Milan convertible into or exchangeable or
exercisable for shares or voting securities or other equity interests of Milan
or (iii) options or other rights to acquire from Milan any shares, voting
securities or other equity interests of Milan or securities convertible into or
exchangeable or exercisable for shares or voting securities or other equity
interests of Milan.

Section 2.05. Finder’s Fees. No investment banker, broker, finder or other
intermediary is entitled to a fee or commission from Milan or the Company in
respect of this Agreement based upon any arrangement or agreement made by or on
behalf of Shareholder.

Section 2.06. Acting in Concert. Subject to any presumptions that exist under
the Code, and so far as Shareholder is aware, Shareholder is not acting in
concert (as such term is understood under the Code) with any other shareholder
of Milan or any stockholder of the Company.

ARTICLE 3

REPRESENTATIONS AND WARRANTIES OF THE COMPANY

The Company represents and warrants to Shareholder that:

Section 3.01. Corporate Authorization. The execution, delivery and performance
by the Company of this Agreement and the consummation by the Company of the
transactions contemplated hereby are within the corporate powers of the Company
and have been duly authorized by all necessary corporate action of the Company.
This Agreement has been duly and validly executed and delivered by the Company
and constitutes a valid and binding agreement of the Company, enforceable
against the Company in accordance with its terms.

 

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ARTICLE 4

COVENANTS OF SHAREHOLDER

Shareholder hereby covenants and agrees that:

Section 4.01. No Proxy Appointment or Encumbrances on Shares. Shareholder shall
not, without the prior written consent of the Company, directly or indirectly,
(i) appoint any proxy or enter into any voting trust or other agreement or
arrangement with respect to the voting of any Shares (except for procuring the
votes as required by this Agreement in accordance with the normal proxy voting
process the Shareholder has in place with the Nominee) or (ii) prior to the Long
Stop Date, sell, assign, transfer, encumber or otherwise dispose of
(“Transfer”), directly or indirectly, or enter into any contract, option or
other arrangement or understanding with respect to the direct or indirect
Transfer of, any Shares during the term of this Agreement. Shareholder shall not
seek or solicit any such Transfer or any such contract, option or other
arrangement or understanding and agrees to notify the Company promptly (and in
any event, within five (5) Business Days), and to provide all details reasonably
requested by the Company, if Shareholder shall be approached or solicited,
directly or indirectly, by any Person with respect to any of the foregoing.
Notwithstanding the foregoing, Shareholder may make Transfers of Shares (A) to
shareholders, corporations, partnerships or other investment or business
entities that are direct or indirect affiliates (within the meaning set forth in
Rule 405 under the Securities Act), or partners (general or limited) of such
Shareholder, as applicable, or to another corporation, partnership or other
investment or business entity that controls, is controlled by or is under common
control with Shareholder, or, if the Shares are held by a nominee shareholder,
to the beneficial owner of such Shares or to another nominee shareholder that
has been engaged by the Shareholder to provide nominee and or custodian services
to it; provided that in each such case, the Shares shall continue to be bound by
this Agreement; (B) to the extent required by law or regulation including,
without limitation, any transfer or disposal required pursuant to regulations
applicable to investment funds that have been established in accordance with the
UCITS (Undertaking for Collective Investment in Transferable Securities)
Directive), or requested by a regulator of competent jurisdiction, or to ensure
compliance with Rule 5.7.2 of the U.K. Financial Conduct Authority’s Collective
Investment Sourcebook or any fund limits as set out in any constitutional or
compliance documentation or otherwise pursuant to any order or ruling by a court
of competent judicial body, or by any competent authority (under Part VI of the
U.K. Financial Services and Markets Act 2000); and (C) to any person who has
executed an irrevocable undertaking in favour of the Company on substantially
similar terms as set out in this Agreement.

 

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Section 4.02. Non-Solicitation. Shareholder and its subsidiaries shall not, and
shall use their best efforts to cause their officers, directors, employees or
other agents not to, directly or indirectly, (i) take any action to solicit,
initiate or knowingly encourage, induce or facilitate any Acquisition Proposal
or any inquiry, proposal or offer that may reasonably be expected to lead to an
Acquisition Proposal, (ii) furnish or disclose any nonpublic information
relating to Milan or any of its Subsidiaries or afford access to the properties,
books or records of Milan or any of its Subsidiaries to, or otherwise knowingly
cooperate in any way with, any Person that may be considering making, is
otherwise seeking to make, or has made, an Acquisition Proposal or has agreed to
endorse an Acquisition Proposal, or (iii) participate in any discussions or
negotiations with any third party that is reasonably expected to make, or has
made, an Acquisition Proposal, regarding an Acquisition Proposal, in each case
other than with respect to an Acquisition Proposal that has been made for 100%
of the issued and outstanding share capital of Milan. Shareholder will promptly
(but in any event within five (5) Business Days) notify the Company upon receipt
of an Acquisition Proposal or any indication that any Person is considering
making an Acquisition Proposal or any request for nonpublic information relating
to Milan or any of its Subsidiaries or for access to the properties, books or
records of Milan or any of its Subsidiaries by any Person that may be
considering making, or has made, an Acquisition Proposal and will keep the
Company fully informed of the status and details of any such Acquisition
Proposal, indication or request, including the identity of the Person making
such Acquisition Proposal, indication or request.

Section 4.03. Waiver of Certain Actions. Shareholder hereby agrees not to
commence or participate in, and to take all reasonable actions to opt out of any
class in any class action with respect to, any action, derivative or otherwise,
against the Company, Milan or any of their respective Affiliates, Subsidiaries,
successors or assigns (a) challenging the validity of, or seeking to enjoin or
delay the operation of, any provision of this Agreement or the Merger Agreement
(including any claim seeking to enjoin or delay the Closing) or (b) to the
fullest extent permitted under Law, alleging a breach of any duty of the board
of directors of the Company or Milan in connection with the Merger Agreement,
this Agreement or the transactions contemplated thereby or hereby.
Notwithstanding the foregoing, this Section 4.03 shall not apply to limit in any
respect the right or ability of a party hereto to enforce the provisions of this
Agreement; provided, that Shareholder may defend against, contest or settle any
such action brought against Shareholder or its Affiliates that relates to
Shareholder’s capacity as a director, officer, shareholder or securityholder of
Milan.

Section 4.04. Prohibited Conduct. Shareholder understands that the information
provided to it in relation to the Merger is given in confidence and must be kept
confidential until the public announcement of the entry into a definitive merger
agreement by Milan and the Company. Before that time, Shareholder will not base
any behavior in relation to the securities of Milan, which would amount to
market abuse for the purposes of Regulation (EU) No 596/2014 of the European
Parliament and of the Council of 16 April 2014 on market abuse, on such
information. Shareholder further acknowledges that some or all of the
information and any other terms or statements made in the course of, or for the
purposes of the Merger (including for the purposes of this Agreement) may
constitute inside information for the purposes of the U.K. Criminal Justice Act
1993 (the “CJA”) and Shareholder is aware of the prohibitions contained in the
CJA (and any other relevant insider dealing legislation) against insider
dealing, encouraging dealing or disclosing such information and agree to abide
by them and undertakes not to engage in behavior prohibited by the CJA.

 

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ARTICLE 5

MISCELLANEOUS

Section 5.01. Other Definitional and Interpretative Provisions. Unless specified
otherwise, in this Agreement the obligations of any party consisting of more
than one Person are joint and several. The words “hereof”, “herein” and
“hereunder” and words of like import used in this Agreement shall refer to this
Agreement as a whole and not to any particular provision of this Agreement. The
captions herein are included for convenience of reference only and shall be
ignored in the construction or interpretation hereof. References to Articles or
Sections are to Articles or Sections of this Agreement unless otherwise
specified. Any singular term in this Agreement shall be deemed to include the
plural, and any plural term the singular. Whenever the words “include”,
“includes” or “including” are used in this Agreement, they shall be deemed to be
followed by the words “without limitation”, whether or not they are in fact
followed by those words or words of like import. “Writing”, “written” and
comparable terms refer to printing, typing and other means of reproducing words
(including electronic media) in a visible form. References to any agreement or
contract are to that agreement or contract as amended, modified or supplemented
from time to time in accordance with the terms hereof and thereof. References to
any Person include the successors and permitted assigns of that Person.
References from or through any date mean, unless otherwise specified, from and
including or through and including, respectively. The parties to this Agreement
agree and acknowledge that: (i) the Shareholder is acting at all times as agent
for and on behalf of the Fund; (ii) the Shareholder shall have no liability as
principal in respect of the Fund’s obligations under this Agreement; and
(iii) all representations, warranties and undertakings are given by the
Shareholder as agent on behalf of the Fund and not as principal.

Section 5.02. Further Assurances. The Company and Shareholder will each execute
and deliver, or cause to be executed and delivered, all further documents and
instruments and use its best efforts to take, or cause to be taken, all actions
and to do, or cause to be done, all things reasonably necessary, proper or
advisable under applicable laws and regulations, to consummate and make
effective the transactions contemplated by this Agreement.

 

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Section 5.03. Amendments; Termination. Any provision of this Agreement may be
amended or waived if, but only if, such amendment or waiver is in writing and is
signed, in the case of an amendment, by each party to this Agreement or, in the
case of a waiver, by the party against whom the waiver is to be effective;
provided that any waiver or amendment of Sections 2.06, 4.04 or this
Section 5.03 (together, the “Specified Sections”) shall require the prior
written consent of Milan. This Agreement shall terminate automatically and
become void and of no further force or effect, without any notice or other
action by any Person, upon the earlier to occur of (a) the Effective Time;
(b) the termination of the Merger Agreement in accordance with its terms; or
(c) September 4, 2019 (“Long Stop Date”). Upon termination of this Agreement,
neither party shall have any further obligations or liabilities under this
Agreement; provided, that nothing set forth in this Section 5.03 shall relieve
any party from liability for any breach of this Agreement prior to termination
hereof.

Section 5.04. Expenses. All costs and expenses incurred in connection with this
Agreement shall be paid by the party incurring such cost or expense.

Section 5.05. Successors and Assigns; No Third-Party Rights. The provisions of
this Agreement shall be binding upon and inure to the benefit of the parties
hereto and their respective successors and assigns; provided that no party may
assign, delegate or otherwise transfer any of its rights or obligations under
this Agreement without the consent of the other parties hereto. Except as
provided in this Section 5.05, nothing in this Agreement is intended to confer
on any Person (other than the parties hereto and their respective successors and
assigns) any rights or remedies of any nature. The parties hereto agree that
Milan shall be an express third party beneficiary of, and shall have the right
to enforce the Specified Sections directly against the parties hereto.

Section 5.06. Governing Law. This Agreement shall be construed in accordance
with and governed by the laws of the State of New York, regardless of the laws
that might otherwise govern under applicable principles of conflicts of laws. In
any action or proceeding between any of the parties arising out of or relating
to this Agreement, each of the parties: (a) irrevocably and unconditionally
consents and submits to the exclusive jurisdiction and venue of the Supreme
Court of the State of New York, County of New York, or, if under applicable Law
exclusive jurisdiction is vested in the Federal courts, the United States
District Court for the Southern District of New York (and appellate courts
thereof); (b) agrees that all claims in respect of such action or proceeding
shall be heard and determined exclusively in accordance with clause (a) of this
Section 5.06; (c) waives any objection to laying venue in any such action or
proceeding in such courts; (d) waives any objection that such courts are an
inconvenient forum or do not have jurisdiction over any party; and
(f) irrevocably waives the right to trial by jury.

Section 5.07. Counterparts; Effectiveness. This Agreement may be signed in any
number of counterparts, each of which shall be an original, with the same effect
as if the signatures thereto and hereto were upon the same instrument. This
Agreement shall become effective when each party hereto shall have received
counterparts hereof signed by all of the other parties hereto. Until and unless
each party has received a counterpart hereof signed by the other party hereto,
this Agreement shall have no effect and no party shall have any right or
obligation hereunder (whether by virtue of any other oral or written agreement
or other communication).

 

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Section 5.08. Severability. If any term, provision or covenant of this Agreement
is held by a court of competent jurisdiction or other authority to be invalid,
void or unenforceable, the remainder of the terms, provisions and covenants of
this Agreement shall remain in full force and effect and shall in no way be
affected, impaired or invalidated.

Section 5.09. Specific Performance. The parties hereto agree that irreparable
damage would occur in the event that any provision of this Agreement is not
performed in accordance with the terms hereof and that the parties shall be
entitled to specific performance of the terms hereof in addition to any other
remedy to which they are entitled at law or in equity.

Section 5.10. Capitalized Terms. Capitalized terms used but not defined herein
shall have the respective meanings set forth in the Merger Agreement.

Section 5.11. Capacity as Shareholder. Shareholder executes and delivers this
Agreement solely in Shareholder’s capacity as agent for and on behalf of a
shareholder of Milan, and not in Shareholder’s capacity as a director, officer
or employee of Milan or in Shareholder’s capacity as a trustee or fiduciary of
any employee benefit plan or trust. Notwithstanding anything in this Agreement
to the contrary, nothing in this Agreement shall in any way restrict a director
or officer of Milan in the exercise of his or her fiduciary duties as a director
or officer of Milan or in his or her capacity as a trustee or fiduciary of any
employee benefit plan or trust, or prevent any director or officer of Milan or
any trustee or fiduciary of any employee benefit plan or trust from taking any
action in his or her capacity as such director, officer, trustee or fiduciary
and none of such actions in such capacity shall be deemed to constitute a breach
of this Agreement.

Section 5.12. Representations and Warranties. The representations and warranties
contained in this Agreement and in any certificate or other writing delivered
pursuant hereto shall not survive the Closing or the termination of this
Agreement.

[Signature page follows]

 

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

 

ONCOMED PHARMACEUTICALS, INC.

By:  

/s/ John A. Lewicki

Name:   John A. Lewicki, Ph. D. Title:   President and Chief Executive Officer

INVESCO INCOME FUND

by INVESCO ASSET MANAGEMENT LIMITED, as agent and on behalf of its discretionary
managed client

By:  

/s/ Paul Joubert

Name:   Paul Joubert Title:   Director

 

    Shares

    Owned    

  2,891,541