Exhibit 10.66

CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT HAS BEEN OMITTED AND
FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION (THE “COMMISSION”)
PURSUANT TO RULE 24b-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED.

Confidential

CYTOKINETICS, INC.
SCIENTIFIC ADVISORY BOARD
CONSULTING AGREEMENT

This Consulting Agreement (the “Agreement”) is made and effective as of April 1,
2008 (the “Effective Date”), by and between Cytokinetics, Inc. (the “Company”)
and James H. Sabry, M.D., Ph.D., an individual (“Consultant”).

WHEREAS, the Company wishes to retain the services of Consultant from time to
time to obtain advice regarding the Field of Interest (as defined below); and

WHEREAS, Consultant wishes to provide such services to the Company in accordance
with the terms and conditions of this Agreement;

NOW, THEREFORE, in consideration of the premises and mutual promises set forth
in this Agreement, and other good and valuable consideration, the exchange,
receipt and sufficiency of which are acknowledged, the parties hereby agree as
follows:

1. Services.

1.1 The Company hereby retains Consultant as a consultant and advisor to the
Company. Consultant’s consultation will involve the specialized field of
pharmaceutical research and development and related business and corporate
development activities (the “Field of Interest”) and requires the application of
the unique, special and extraordinary skills and knowledge that Consultant
possesses in the Field of Interest.

1.2 Consultant hereby agrees to perform the following services for the Company
under this Agreement (the “Services”), as requested by the Company:

(i) Chair the Company’s Scientific Advisory Board and attend formal meetings
with Company’s scientists or management or as otherwise designated by Company;

(ii) Mentoring of the Company’s staff as assigned;

(iii) During the months of April-June 2008 support smooth transition and
implementation of the R&D strategic planning initiative:

(iii) Advise the Company’s management, employees and agents, at reasonable
times, in matters related to the Field of Interest; and

(iv) Provide such other consultation or advisory services as may be requested by
the Company.

1.3 Consultant will provide the Services over the telephone or through written
or electronic correspondence as requested by the Company, and will make himself
available in person at the Company’s offices or other locations at mutually
agreeable times. From the Effective Date through June 30, 2008, the parties
anticipate that Consultant will provide twelve

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(12) days of consulting per month. Thereafter, parties anticipate that
Consultant will provide two (2) days of consulting per month.

1.4 Consultant hereby represents and warrants that he or she will perform the
Services using at all times his best professional knowledge, ability, skill,
judgment and efforts, in a workman-like manner, and in accordance with the
highest standards of competence, diligence and performance.

2. Expenses. The Company will reimburse Consultant’s reasonable, documented
expenses incurred at the Company’s request in connection with the Services
(including travel expenses, which will be reimbursed in accordance with the
Company’s standard travel policy), subject to customary verification in a form
reasonably acceptable to the Company. Invoices for expenses and accompanying
documentation must be submitted within thirty (30) days of the end of the month
in which such expenses were incurred. The Company will pay correct invoices
within thirty (30) days of receipt.

3. Compensation. From the Effective Date through June 30, 2008, Consultant will
receive a monthly fee of thirty thousand dollars ($30,000). Thereafter,
Consultant will receive a monthly fee of five thousand dollars ($5,000). Such
fees will be paid in arrears within thirty (30) days from the end of each month
during the term of this Agreement, pro-rated for partial months. Travel time is
not compensable. The compensation paid under this Section 3 will be deemed full
compensation for Consultant’s performance of the Services and all other
obligations undertaken by Consultant hereunder.

4. Term and Termination. This Agreement will take effect as of the Effective
Date and continue for an initial term expiring December 31, 2008, and will then
automatically renew for successive one-year terms. Either party may terminate
this Agreement at any time, with or without cause, upon sixty (60) days prior
written notice to the other party. The obligations of Sections 4, 5, 6.2, 7, 8,
9, 11, 12 and 13 hereof will survive expiration or any termination of this
Agreement. Expiration or termination of this Agreement will not relieve either
party of any liability or obligation which accrued hereunder prior to the
effective date of such termination, nor preclude either party from pursuing all
rights and remedies it may have hereunder or at law or in equity with respect to
any breach of this Agreement, nor prejudice either party’s right to obtain
performance of any obligation.

5. Inventions.

5.1 Consultant will promptly disclose in writing to the Company’s President, or
to any other persons designated by the Company, all “Company Inventions.” As
used herein, “Company Inventions” means all improvements, inventions, designs,
formulas, compounds, structures, works of authorship, trade secrets, technology,
computer programs, ideas, processes, techniques, know-how, data and information,
whether or not patentable or copyrightable, which Consultant, either alone or
jointly, makes, discovers, conceives of and/or reduces to practice in the course
of or as a result of performing Services, or through use of any Confidential
Information (as defined below). Consultant will not disclose Company Inventions
to any person outside the Company unless the Company so requests in writing.

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5.2 All Company Inventions and all title, patents, patent rights, copyrights,
mask work rights, trade secret rights and other intellectual property and rights
anywhere in the world in connection therewith (collectively “Rights”) will be
the Company’s sole and exclusive property. Consultant hereby assigns, and
automatically will be deemed to have assigned, to the Company all Rights in and
to all Company Inventions.

5.3 Consultant agrees to perform, during and after the term of this Agreement,
all acts the Company reasonably deems necessary or desirable to permit and
assist it in evidencing, perfecting, obtaining, maintaining, defending and
enforcing its Rights in the Company Inventions and/or Consultant’s assignment
with respect thereto in any and all countries. Such acts may include, but are
not limited to, execution of documents and assistance in legal proceedings. If
for any reason whatsoever the Company is unable to secure Consultant’s signature
on any document needed in connection with furthering the purposes of this
Section 5.3, Consultant hereby irrevocably designates and appoints the Company
and its duly authorized officers and agents as Consultant’s agents and
attorneys-in-fact, to act for and in behalf and instead of Consultant, to
execute and file any documents and to do all other lawfully permitted acts to
further the purposes of this Section 5.3 with the same legal force and effect as
if executed by Consultant.

5.4 Any assignment of copyright hereunder includes all rights of paternity,
integrity, disclosure and withdrawal and any other rights that may be known as
or referred to as “moral rights” (collectively “Moral Rights”). To the extent
such Moral Rights cannot be assigned under applicable law and to the extent the
following is allowed by the laws in various countries where Moral Rights exist,
Consultant hereby waives such Moral Rights and consents to any action of the
Company that would violate such Moral Rights in the absence of such consent.
Consultant will confirm any such waivers and consents as requested by the
Company.

6. Third Party Agreements; Segregation of Services.

6.1 Subject to written waivers that the Company may provide upon request and
which it will not unreasonably withhold, Consultant will not directly or
indirectly, during the term of this Agreement: (i) provide any services in the
Excluded Field (as defined below) to any other business or commercial entity,
(ii) provide any services for any company that is competitive with the Company,
or (iii) participate in the formation of any business or commercial entity in
the Field of Interest or otherwise competitive with the Company. Consultant will
list in Exhibit A attached hereto all other companies for which Consultant is
providing services (“Outside Companies”) as of the Effective Date, and will
promptly update such list as new engagements arise during the term of this
Agreement. As used herein, “Excluded Field” means activities (including, without
limitation, pharmacology and clinical applications) relating to: (a) [***] (b)
[***]; (c) [***]; (d) [***]; or (e) any other current (as of the Effective Date)
or future molecular target, biology or pathway that is the subject of a Company
research or development program, provided that if Consultant is unable to commit
to exclusivity with respect to any future molecular target, biology or pathway
he will promptly inform the Company and the parties will agree upon an
appropriate resolution (which may include Consultant’s recusal from discussions
relating to such molecular target, biology or pathway).

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*** Certain information on this page has been omitted and filed separately with
the Commission. Confidential treatment has been requested with respect to the
omitted portions.

6.2 Consultant will not perform the Services on time that is required to be
devoted to any third party. Consultant will not use the funding, resources,
materials, personnel or facilities of any third party to perform the Services
without the Company’s prior written consent, and will not perform the Services
in any manner that would give any third party rights or access to any products
of the Services. Without limiting the generality of the foregoing, Consultant
will: (i) segregate the Services from Consultant’s work performed for any third
party so as to minimize any questions of disclosure of, or rights under, any
intellectual property; (ii) immediately notify the Company in writing if at any
time Consultant believes that such questions may result from his or her
performance under this Agreement; and (iii) assist the Company in fairly
resolving any questions in this regard which may arise. Consultant represents
and warrants that he or she has disclosed and immediately will disclose to the
Company any conflicts between this Agreement and any other agreements binding
Consultant.

6.3 Consultant will not disclose to the Company any information that Consultant
is obligated to keep secret pursuant to a confidentiality agreement with a third
party, and nothing in this Agreement will impose any obligation on Consultant to
the contrary.

6.4 During the term of this Agreement, subject to Consultant’s confidentiality
obligations to third parties, Consultant will disclose to the Company’s
President, on a confidential basis, technology and product opportunities which
come to Consultant’s attention in the Excluded Field, and any invention,
improvement, discovery, process, formula or method or other intellectual
property relating to or useful in, the Excluded Field, whether or not patentable
or copyrightable, and whether or not discovered or developed by Consultant.

7. Non-Solicitation. During the term of this Agreement and for a period of
twelve (12) months thereafter, Consultant will not, directly or indirectly,
solicit, hire away, or induce to leave any employee or consultant of the
Company.

8. Confidentiality.

8.1 As used herein, “Confidential Information” means: (i) any information
disclosed to Consultant by or on behalf of the Company, either directly or
indirectly, in writing, graphically, electronically, orally or by inspection,
including, without limitation, information comprising or relating to any:
(a) compound, extract, media, vector, gene, protein, sequence, cell, cell line,
formulation, sample or other composition, including, without limitation, any
structural information or methods of synthesis relating to any of the foregoing;
(b) assay, procedure, algorithm, software program, discovery, invention, model,
formula, data, result, idea or technique; (c) trade secret, trade dress,
copyright, patent or other intellectual property right or any registration or
application therefor or materials relating thereto; or (d) research,
development, purchasing, manufacturing, engineering, marketing, servicing,
sales, financing, legal or other business or corporate financial activities
and/or present or future products, design details or specifications, prices,
plans, forecasts, suppliers, clients, customers, employees, consultants or
investors; (ii) all information developed by or for Consultant pursuant to the
Services, including, without limitation, all Company Inventions; (iii) any
information which the Company has received from a third party which the Company
is obligated to treat as confidential or proprietary; and (iv) the terms,
existence and subject matter of this Agreement. Consultant

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acknowledges that the Company’s business is extremely competitive, dependent
upon the maintenance of secrecy and any disclosure of any Confidential
Information would result in serious harm to the Company.

8.2 Consultant will use the Confidential Information only as necessary for the
Services, and will not use any Confidential Information in any way detrimental
to the Company.

8.3 Consultant will:

(i) hold the Confidential Information and any information derived therefrom in
strictest confidence and protect such Confidential Information (including,
without limitation, taking at least that level of care Consultant employs with
respect to his or her most sensitive confidential materials, but in any event a
reasonable level of care);

(ii) maintain all Confidential Information and any information derived therefrom
wholly separate from information provided to Consultant by or belonging to any
third party;

(iii) not take any Confidential Information or any information derived therefrom
into the facilities of any third party;

(iv) not, directly or indirectly, disclose, transfer or otherwise make available
any Confidential Information or any information derived therefrom to any third
person; and

(v) not copy or reverse engineer any Confidential Information.

8.4 The term “Confidential Information” does not include any information that
Consultant can show by competent, written proof:

(i) is or becomes generally known to the public through no improper action or
inaction by Consultant;

(ii) was in Consultant’s possession or known to Consultant prior to receipt from
the Company; or

(iii) was rightfully disclosed to Consultant by a third party without
restriction on further disclosure.

Notwithstanding the foregoing, all Company Inventions will remain at all times
Confidential Information.

8.5 Consultant may disclose any Confidential Information that is duly required
to be disclosed by law, government regulation or court order. If such disclosure
is required, Consultant will give the Company at least 30 days advance written
notice, or such advance written notice as is reasonably practicable under the
circumstances, to enable the Company to seek confidential treatment of such
Confidential Information, whether by protective order or otherwise, and
Consultant will cooperate fully with the Company in such efforts.

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8.6 Consultant will notify the Company in writing immediately upon becoming
aware of any unauthorized release or other breach of this Section 8.

8.7 Upon the earlier of expiration or termination of this Agreement, or upon the
Company’s request, Consultant will promptly return to the Company all materials
containing Confidential Information as well as data, records, reports, notes,
compilations and other property, whether or not pertaining to Confidential
Information, furnished by the Company to Consultant or produced by Consultant in
connection with the Services rendered hereunder, together with all copies of any
of the foregoing.

8.8 Consultant is not granted any rights under any of the Company’s patent
rights, copyrights or other property rights, nor will this Agreement grant
Consultant any rights in or to any Confidential Information, except for the
purpose of providing Services to the Company.

9. Use of Name. Consultant’s name may appear on the Company’s website as a
member of the Company’s scientific advisory board and in certain Company
disclosure documents, including, without limitation: (i) those provided to
investors, potential investors, advisors, partners and affiliates of the
Company; and (ii) those required by securities laws and in other regulatory and
administrative filings in the ordinary course of the Company’s business.
Consultant will not use the Company’s name without the Company’s prior written
consent.

10. No Conflict: Valid and Binding. Each party represents and warrants that
neither the execution of this Agreement nor the performance of its obligations
under this Agreement will result in a violation or breach of any other agreement
by which such party is bound, and that this Agreement is valid and legally
binding in accordance with its terms.

11. Compliance with Company Policies. Consultant agrees to fully comply with all
of the Company’s then-current policies and procedures, including, without
limitation, the Company’s Insider Trading Compliance Program.

12. Anti-Harassment Policy. The Company is committed to providing a work
environment free of discrimination and harassment, and discrimination or
harassment of any kind is strictly prohibited. Contractor’s engaging in unlawful
sexual harassment, other harassment or discrimination on any protected bases may
result in the immediate termination of this Agreement.

13. Miscellaneous.

13.1 No Debarment.

(i) Consultant hereby represents and warrants that:

(a) He or she has not been debarred under the Generic Drug Enforcement Act or
any similar law or regulation; and

(b) He or she has not been indicted for or convicted of a felony under any
applicable law or regulation for conduct: (1) relating to the development or
approval, including the process for development or approval, of any drug,
product or medical device; or (2)

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otherwise relating to the regulation of any drug product or medical device under
the FD&C Act or any similar law.

(ii) Consultant will immediately inform the Company in writing of any debarment,
or the commencement of any debarment or like proceedings against Consultant
during the term of this Agreement. In such event, the Company may terminate this
Agreement effective upon Consultant’s receipt of written notice thereof.

13.2 Notices. Any notice provided under this Agreement will be in writing and
will be deemed to have been effectively given (i) upon receipt when delivered
personally, (ii) one day after sending when sent by private express mail service
(such as Federal Express), or (iii) 3 days after sending when sent by regular
mail to the following address:

In the case of the Company:

Cytokinetics, Inc.

280 East Grand Avenue

South San Francisco, CA 94080

Attn: President and CEO

In the case of Consultant:

James H. Sabry, M.D., Ph.D.
[***]
[***]

or to other such address as may have been designated by the Company or
Consultant by notice to the other given as provided herein.

13.3 Independent Contractor: Withholding. Consultant will at all times be an
independent contractor, and as such will not have authority to bind the Company.
Consultant will not enter into any agreements or incur any obligations on the
Company’s behalf. Consultant will not act as an agent nor be deemed to be an
employee of the Company for the purposes of any employee benefit program,
unemployment benefits, or otherwise. The Company will not withhold any amounts
from Consultant’s compensation for payment of any federal, state, or local
taxes, and Consultant has sole responsibility to pay such taxes, if any, and
file such returns as will be required by applicable laws and regulations. To the
extent required by laws and regulations of the State of California and the U.S.
Government, the Company will report such compensation to the appropriate state
and federal regulatory agencies. Consultant hereby indemnifies the Company
against any obligation imposed on the Company to pay withholding taxes or
similar items or resulting from a court’s or governmental entity’s determination
that Consultant is not an independent contractor to the Company.

13.4 Assignment. Due to the personal nature of the Services to be rendered by
Consultant, Consultant may not assign this Agreement. The Company may assign all
rights and liabilities under this Agreement to a subsidiary or an affiliate or
to a successor to all or a substantial part of its business and assets without
Consultant’s consent. Subject to the foregoing,

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*** Certain information on this page has been omitted and filed separately with
the Commission. Confidential treatment has been requested with respect to the
omitted portions.

this Agreement will inure to the benefit of and be binding upon each of the
heirs, assigns and successors of the respective parties. Any purported
assignment that does not comport with this Section will be null, void and of no
effect.

13.5 Severability. If any provision of this Agreement is declared invalid,
illegal or unenforceable by a court of competent jurisdiction, such provision
will be severed and the remaining provisions will continue in full force and
effect.

13.6 Remedies. The remedies provided hereunder are cumulative, and are not
exclusive of other remedies available to either party in law or equity.
Consultant hereby acknowledges and agrees that in the event of Consultant’s
actual or threatened breach of this Agreement relating to confidentiality and/or
intellectual property, including, without limitation, the actual or threatened
disclosure of Confidential Information without the Company’s prior express
written consent, the Company will suffer an irreparable and continuing injury
such that no remedy at law will afford it adequate protection against, or
appropriate compensation for, such injury. Accordingly, Consultant hereby agrees
that, in such event, and in addition to any other remedies that may be available
in law, in equity or otherwise, the Company will be entitled to obtain
injunctive relief against such breach or threatened breach of this Agreement
without the necessity of proving actual damages or posting bond.

13.7 Governing Law; Dispute Resolution. This Agreement will be governed and
construed in accordance with the laws of the State of California as applied to
transactions taking place wholly within California between California residents.
For any legal action arising from or related to this Agreement, the parties
hereby irrevocably: (i) consent and submit solely to jurisdiction and venue of
the state and federal courts located in San Francisco County, California;
(ii) agree that such courts will be the sole courts utilized; and (iii) waive
any jurisdictional or venue objections to such courts, including, without
limitation, forum non conveniens. The prevailing party in any action to enforce
this Agreement will be entitled to costs and attorneys’ fees. No provision of
this Agreement will be strictly construed against either party, irrespective of
which party is deemed to have authored such provision.

13.8 Entire Agreement; Amendment. This Agreement represents the entire
understanding of the parties relating to the subject matter hereof and
supersedes all prior agreements between the parties relating to such subject
matter. This Agreement may only be amended in writing executed by the Company
and Consultant. For clarity, this Agreement is not intended to supersede or
modify Consultant’s fiduciary obligations as a member of the Company’s Board of
Directors.

13.9 Indemnification. Consultant will indemnify and hold the Company and its
directors, officers, employees and agents harmless from and against any and all
damages, costs, expenses, losses and other liabilities, including, without
limitation, reasonable attorney’s fees and court costs, incurred in connection
with any claim, action or proceeding arising in connection with Consultant’s
negligence, intentional misconduct or breach of any obligation, representation
or warranty hereunder.

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13.10 Headings. The headings for each Article and Section in this Agreement have
been inserted for convenience of reference only and are not intended to limit or
expand on the meaning of the language contained in the particular Article or
Section.

13.11 Waiver. Waiver or forbearance by either party or the failure by either
party to claim a breach of any provision of this Agreement or exercise any right
or remedy provided by this Agreement or applicable law will not be deemed to
constitute a waiver with respect to any subsequent breach of any provision
hereof, excepting only as to an express written and signed waiver as to a
particular matter for a particular period of time.

13.12 Further Actions. Consultant agrees to execute, acknowledge and deliver
such further instruments, and to do all such other acts, as may be necessary or
appropriate in order to carry out the purposes and intent of this Agreement.

13.13 Counterparts. This Agreement may be executed in two or more counterparts,
each of which will be deemed an original and all of which will together be
deemed to constitute one agreement

IN WITNESS WHEREOF, the parties have executed this Agreement as of the Effective
Date.

     
CYTOKINETICS, INC.
By:
  CONSULTANT
By:
/s/ Robert I. Blum
  /s/ James H. Sabry
 
   
Print Name: Robert I. Blum
  Print Name: James H. Sabry, M.D., Ph.D.
 
   
Title: President and CEO
  Taxpayer I.D. Number:
 
   
Date:
  Date:
3/27/08
  3/31/08
 
   

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1

EXHIBIT A

OUTSIDE COMPANIES

Arete Therapeutics, Inc.

Prospect Venture Partners

Hopelab

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2