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Exhibit 10.3

EMPLOYMENT AGREEMENT

        AGREEMENT, made and entered into as of June 18, 2008 by and between
Vertex Pharmaceuticals Incorporated, a Massachusetts corporation (together with
its successors and assigns, the "Company"), and Freda Lewis-Hall (the
"Executive").

WITNESSETH

        WHEREAS, the Company has offered to employ the Executive as the
Executive Vice President, Medicines Development;

        WHEREAS, the Company and the Executive desire to enter into an
employment agreement, which shall set forth the terms of such employment (this
"Agreement"); and

        WHEREAS, the Executive desires to enter into this Agreement and to
accept such employment, subject to the terms and provisions of this Agreement.

        NOW, THEREFORE, in consideration of the premises and mutual covenants
contained herein and for other good and valuable consideration, the receipt of
which mutually is acknowledged, the Company and the Executive (each individually
a "Party", and together the "Parties") agree as follows:

1.    DEFINITIONS.

        "Base Salary" shall mean the Executive's base salary in accordance with
Section 4 below.

        "Board" shall mean the Board of Directors of the Company.

        "Cause" shall mean:

(i)the Executive is convicted of a crime involving moral turpitude;

(ii)the Executive's willful refusal or failure to follow a lawful directive or
instruction of the Company's Board of Directors or the individual(s) to whom the
Executive reports, provided that the Company shall have given the Executive
prior written notice of the directive(s) or instruction(s) that the Executive
failed to follow, and provided, further, that the Company shall have given the
Executive, in good faith, 30 days to correct such failure and further provided
that if the Executive corrects such failure, any termination of the Executive's
employment on account of such failure shall not be treated for purposes of this
Agreement as a termination of employment for "Cause;"

(iii)the Executive violates any of the Company's policies made known to the
Executive regarding confidentiality, securities trading or insider information;
or

(iv)the Executive, in carrying out the Executive's duties, commits (A) willful
gross negligence or (B) willful gross misconduct resulting, in either case, in
material harm to the Company unless such act, or failure to act, was believed by
the Executive, in good faith, to be in the best interests of the Company.

        "Change of Control" shall have the meaning set forth in the Change of
Control Agreement.

        "Change of Control Agreement" shall mean the Change of Control letter
agreement between the Company and the Executive of even date herewith.

        "Code" shall mean the Internal Revenue Code of 1986, as amended.

        "Common Stock" shall mean the common stock of the Company.

        "Disability" or "Disabled" shall mean a disability as determined under
the Company's long-term disability plan or program in effect at the time the
disability first occurs, or if no such plan or program exists at the time of
disability, then a "disability" as defined under Section 22(e)(3) of the Code.

        "Effective Date" shall mean June 18, 2008.

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        "Good Reason" shall mean that, without the Executive's consent, one or
more of the following events occurs, and the Executive, at the Executive's own
initiative provides notice of termination within 30 days after such event:

(i)the Executive's Base Salary is decreased or the target levels under the
Company's target bonus program, or equity compensation program are reduced,
unless each or any such reduction is part of an across-the-board proportionate
reduction in the salaries, target bonuses, or target equity compensation, as
applicable, provided, however, that it is expressly understood that payments or
awards under any such program in amounts lower than the target amounts in
accordance with any such program shall not constitute "Good Reason;"

(ii)the office to which the Executive is assigned is relocated to a place 35 or
more miles away and such relocation is not at the Executive's request or with
the Executive's prior agreement (and other than, for Executives assigned to the
Company's principal executive offices, in connection with a change in location
of the Company's principal executive offices); or

(iii)the Executive's duties are materially diminished to an extent that results
in either (A) the Executive no longer being an "officer," as such term is
defined in Rule 16a-1(f) promulgated under the Securities Exchange Act of 1934;
or (B) the Executive ceases to be a member of the executive management team of
the Company.

        "Severance Payment" shall mean an amount equal to the sum of the Base
Salary in effect on the date of termination of Executive's employment, plus the
amount of the Target Bonus for the Executive for the year in which the
Executive's employment is terminated; provided, however, that if the Executive
terminates the Executive's employment for Good Reason based on a reduction in
Base Salary, then the Base Salary to be used in calculating the Severance
Payment shall be the Base Salary in effect immediately prior to such reduction
in Base Salary.

        "Target Bonus" shall mean the target cash bonus for which the Executive
is eligible on an annual basis, at a level consistent with the Executive's title
and responsibilities, under the Company's bonus program then in effect and
applicable to the Company's senior executives generally.

2.TERM OF EMPLOYMENT.

        The Company hereby employs the Executive, and the Executive hereby
accepts such employment, commencing on the Effective Date and continuing until
termination in accordance with the terms of this Agreement. The period during
which the Executive is employed hereunder is referred to in this Agreement as
the "term of employment."

3.POSITION, DUTIES AND RESPONSIBILITIES.

        On the Effective Date, the Executive shall be employed as Executive Vice
President, Medicines Development.

4.    BASE SALARY.

        The Executive's initial annualized Base Salary shall be $450,000,
payable in accordance with the regular payroll practices of the Company. The
Base Salary shall be reviewed no less frequently than annually, and any changes
thereto (which shall thereafter be deemed the Executive's Base Salary) shall be
solely within the discretion of the Board.

5.TARGET BONUS/INCENTIVE COMPENSATION PROGRAM.

        (a)   Target Bonus Program:    The Executive shall participate in the
Company's Target Bonus program (and other cash incentive compensation programs)
applicable to the Company's senior executives, as any such programs are
established and modified from time to time by the Board in its sole discretion,
and in accordance with the terms of such program.

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        (b)   Sign-On Cash Bonus:    The Executive shall receive a sign-on cash
bonus in the amount of $250,000 payable (with appropriate deductions as required
by law) to the Executive at the first regular pay date applicable to the
Executive after the Effective Date. If the Executive terminates this Agreement
without Good Reason, and other than as a result of death or Disability, during
the period commencing on the Effective Date and ending on the first anniversary
of the Effective Date, the Executive shall repay the sign-on cash bonus to the
Company within 30 days of such termination.

        (c)   Sign-On Stock Option Grant:    The Executive shall be granted a
stock option under the Company's 2006 Stock and Option Plan (the "Stock Plan"),
to purchase 100,000 shares of the Company's common stock at a price equal to the
Fair Market Value of Vertex's shares, as defined in the Stock Plan, on the
Effective Date. The option will vest and become exercisable as to equal numbers
of shares of stock quarterly in arrears over the four year period commencing on
the Effective Date, and as otherwise specified herein and in the Stock Plan, and
shall be subject to the other terms and conditions specified in a separate grant
agreement.

        (d)   Sign-On Restricted Stock Grants:

(i)The Executive will purchase, in accordance with the terms of a Restricted
Stock Agreement executed and delivered to the Company by the Executive on the
Effective Date (the "Grant Date"), 35,000 shares of the Company's Common Stock,
at a purchase price per share of $0.01. The Company will retain the right to
repurchase these shares at $0.01 per share purchase price should the Executive
experience a termination of employment, as such term is used in the Stock Plan,
but this repurchase right will lapse as to one quarter of the total number of
shares on each of the first four anniversaries of the Grant Date, and as
otherwise specified herein (including in Section 10(c)(v)) and in the Stock
Plan, and shall be subject to the other terms and conditions specified in a
separate grant agreement.

(ii)The Executive will purchase, in accordance with the terms of a Restricted
Stock Agreement executed and delivered to the Company on the Grant Date, 10,000
shares of the Company's Common Stock, at a purchase price per share of $0.01.
The Company will retain the right to repurchase these shares at a purchase price
of $0.01 per share, should the Executive experience a termination of employment,
as such term is used in the Stock Plan, but this repurchase right shall lapse as
to equal number of shares of stock quarterly in arrears over the two (2) year
period commencing on the Grant Date, and as otherwise specified herein and in
the Stock Plan (including in Section 10(c)(v)) and shall be subject to the other
terms and conditions specified in a separate grant agreement.

6.INCENTIVE COMPENSATION PROGRAMS.

        During the term of employment, the Executive shall be eligible to
participate in the Company's incentive compensation programs applicable to the
Company's senior executives, as such programs may be established and modified
from time to time by the Board in its sole discretion.

7.EMPLOYEE BENEFIT PROGRAMS.

        During the term of employment, the Executive shall be entitled to
participate in all employee welfare and pension benefit plans, programs and/or
arrangements offered by the Company to its senior executives, as such plans,
programs and arrangements may be amended from time to time, to the same extent
and on the same terms applicable to other senior executives. Exhibit A to this
Agreement lists and describes the Company's employee benefit plans as in effect
on the date of this Agreement. Nothing in this section shall preclude the
Company from amending or terminating any of its employee benefit plans, programs
or arrangements.

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8.VACATION.

        During the term of employment, the Executive shall be entitled to not
less than four weeks paid vacation days each calendar year in accordance with
the Company's vacation policy then in effect.

9.RELOCATION REIMBURSEMENT.

        The Executive will be reimbursed for relocation costs in accordance with
the Company's relocation reimbursement policy currently in effect, except that
the Executive shall be eligible for reimbursement of temporary living expenses
for a period not to exceed six (6) months.

10.TERMINATION OF EMPLOYMENT.

        (a)   Termination in Connection with a Change of Control.    To the
extent the Executive is entitled, in connection with the Executive's termination
of employment, to severance or other benefits under the Change of Control
Agreement, the Executive shall not be entitled to corresponding benefits under
this Section 10.

        (b)   Termination by the Company for Cause; or Termination by the
Executive without Good Reason.    If the Company terminates the Executive's
employment for Cause, or if the Executive voluntarily terminates the Executive's
employment, other than for Good Reason, death or Disability, the term of
employment shall end as of the date specified below, and the Executive shall be
entitled to the following:

(i)Base Salary earned by Executive but not paid through the date of termination
of Executive's employment under this Section 10(b); and

(ii)any amounts earned, accrued or owing to the Executive but not yet paid under
Sections 6, 7, or 8 above.

        Termination by Company for Cause shall be effective as of the date
noticed by the Company. Voluntary termination by Executive other than for Good
Reason, death or Disability shall be effective upon 90 days' prior written
notice to the Company and shall not be deemed a breach of this Agreement.

        If the Executive voluntarily terminates his or her employment without
Good Reason, the Company may elect to waive the period of notice, or any portion
thereof, and, if the Company so elects, the Company will pay the Executive at
the rate of the Executive's Base Salary for the notice period or for any
remaining portion thereof.

        (c)   Termination by the Company Without Cause; or Termination by the
Executive for Good Reason.    If the Executive's employment is terminated by the
Company without Cause (other than due to death or Disability), or is terminated
by the Executive for Good Reason, the Executive shall be entitled to the
following (provided that, with respect to (iii), (v) and (vi) such amounts shall
be subject to and in exchange for a general release by Executive of all claims
against the Company, its subsidiaries, and their officers, directors, agents and
representatives):

(i)Base Salary earned by Executive but not paid through the date of termination
of Executive's employment under this Section 10(c);

(ii)all incentive compensation awards earned by Executive but not paid prior to
the date of termination of Executive's employment under this Section 10(c);

(iii)a cash payment to the Executive in an amount equal to the Severance
Payment, payable within ten days after the execution of a general release and
expiration without revocation of any applicable revocation periods under the
general release;

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(iv)any amounts earned, accrued or owing to the Executive but not yet paid under
Sections 6, 7 or 8 above;

(v)the Company's lapsing repurchase right with respect to the shares of common
stock purchased by the Executive pursuant to Section 5(d) of this Agreement
shall lapse in full;

(vi)if COBRA coverage is elected by the Executive, the Company shall pay the
cost of COBRA continuation premiums on the Executive's behalf to continue
standard medical, dental and life insurance coverage for the Executive (or the
cash equivalent of the same if the Executive is ineligible for continued
coverage) until the earlier of:

(A)the date 12 months after the date the Executive's employment is terminated;
or

(B)the date, or dates, on which the Executive receives equivalent coverage and
benefits under the plans, programs and/or arrangements of a subsequent employer
(such coverage and benefits to be determined on a coverage-by-coverage or
benefit-by-benefit basis).

        If Executive is a "specified employee" under Section 409A(a)(2)(B)(i) of
the Code, any payment of "nonqualified deferred compensation" (as defined under
Section 409A of the Code and related guidance) attributable to a "separation
from service" (as defined under Section 409A of the Code and related guidance)
shall not commence until the first full business day that is more than 6 months
after the applicable separation from service ("Deferred Payment Date"). Any
payments that would otherwise have been made between the separation from service
and the Deferred Payment Date, but for this paragraph, shall be made in a lump
sum on the Deferred Payment Date. Payments that, in any case, are scheduled to
be made after the Deferred Payment Date shall continue according to the
applicable payment schedule. To the extent that the termination of the
Executive's employment does not constitute a separation of service under
Section 409A(a)(2)(A)(i) of the Code (as the result of further services that
reasonably are anticipated to be provided by the Executive to the Company at the
time the Executive's employment is terminated), the payment of any nonqualified
deferred compensation will be further delayed until the date that is the first
full business day that is more than six months after the date of a subsequent
event constituting a separation of service under Section 409A(a)(2)(A)(i) of the
Code.

11.    CONFIDENTIALITY; ASSIGNMENT OF RIGHTS, NONCOMPETITION; NONSOLICITATION.

        On the Effective Date, the Executive shall enter into the Company's
standard "Employee Non-Disclosure, Non-Competition & Inventions Agreement,"
which is attached hereto as Exhibit B.

12.ASSIGNABILITY; BINDING NATURE.

        This Agreement shall be binding upon and inure to the benefit of the
Parties and their respective successors, heirs (in the case of the Executive)
and assigns. No rights or obligations of the Company under this Agreement may be
assigned or transferred by the Company except that such rights or obligations
may be assigned or transferred pursuant to a merger or consolidation in which
the Company is not the continuing entity, or the sale or liquidation of all or
substantially all of the assets of the Company; provided, however, that the
assignee or transferee is the successor to all or substantially all of the
assets of the Company and such assignee or transferee assumes the liabilities,
obligations and duties of the Company, as contained in this Agreement, either
contractually or as a matter of law.

13.REPRESENTATIONS.

        The Company represents and warrants that it is fully authorized and
empowered to enter into this Agreement, and to make the awards provided for
herein under the terms of the applicable plans, that all equity grants provided
for herein have been duly authorized, and that the performance of its

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obligations under this Agreement will not violate any agreement between it and
any other person, firm or organization. The Executive represents and warrants
that no agreement exists between him and any other person, firm or organization
that would be violated by the performance of the Executive's obligations under
this Agreement.

14.    INDEMNIFICATION; INSURANCE.

        The Executive shall at all times be indemnified and eligible for
advancement of expenses on the same basis as is provided for the Company's other
executive officers and in accordance with the provisions of the Company's
charter and by-laws then in effect. The Executive shall also be covered under
all of the Company's policies of liability insurance maintained for the benefit
of its directors and officers on the same basis as is provided for its other
executive officers.

15.ENTIRE AGREEMENT; TERMINATION.

        This Agreement, and the agreements referenced herein, contain the entire
understanding and agreement between the Parties concerning the subject matter
hereof and supersedes all prior agreements, understandings, discussions,
negotiations and undertakings, whether written or oral, between the Parties with
respect thereto. Subject to the terms of this Agreement, the Company shall be
entitled to terminate the Executive's employment at any time, and the Executive
may terminate the Executive's employment by the Company, at any time, in each
case by written notice provided in accordance with Section 22 of this Agreement.

16.AMENDMENT OR WAIVER.

        No provision in this Agreement may be amended unless such amendment is
agreed to in writing and signed by the Executive and an authorized officer of
the Company. No waiver by either Party of any breach by the other Party of any
condition or provision contained in this Agreement to be performed by such other
Party shall be deemed a waiver of a similar or dissimilar condition or provision
at the same or any prior or subsequent time. Any waiver must be in writing and
signed by the Executive or an authorized officer of the Company, as the case may
be.

17.SEVERABILITY.

        If any provision or portion of this Agreement shall be determined to be
invalid or unenforceable for any reason, in whole or in part, the remaining
provisions of this Agreement shall be unaffected thereby and shall remain in
full force and effect to the fullest extent permitted by law.

18.SURVIVORSHIP.

        The respective rights and obligations of the Parties hereunder shall
survive any termination of the Executive's employment to the extent necessary to
the intended preservation of such rights and obligations.

19.BENEFICIARIES/REFERENCES.

        The Executive shall be entitled, to the extent permitted under any
applicable law, to select and change a beneficiary or beneficiaries to receive
any compensation or benefit payable hereunder following the Executive's death by
giving the Company written notice thereof. In the event of the Executive's death
or a judicial determination of the Executive's incompetence, reference in this
Agreement to the Executive shall be deemed, where appropriate, to refer to the
Executive's beneficiary, estate or other legal representative.

20.GOVERNING LAW/JURISDICTION.

        This Agreement shall be governed by and construed and interpreted in
accordance with the laws of The Commonwealth of Massachusetts without reference
to principles of conflict of laws.

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21.RESOLUTION OF DISPUTES.

        Any disputes arising under or in connection with this Agreement may, at
the election of the Executive or the Company, be resolved by binding
arbitration, to be held in Massachusetts in accordance with the Rules and
Procedures of the American Arbitration Association. If arbitration is elected,
the Executive and the Company shall mutually select the arbitrator. If the
Executive and the Company cannot agree on the selection of an arbitrator, each
Party shall select an arbitrator and the two arbitrators shall select a third
arbitrator, and the three arbitrators shall form an arbitration panel that shall
resolve the dispute by majority vote. Judgment upon the award rendered by the
arbitrator or arbitrators may be entered in any court having jurisdiction
thereof. Costs of the arbitrator or arbitrators and other similar costs in
connection with an arbitration shall be shared equally by the Parties; all other
costs, such as attorneys' fees incurred by each Party, shall be borne by the
Party incurring such costs.

22.NOTICES.

        All notices that are required or permitted hereunder shall be in writing
and sufficient if delivered personally, sent by facsimile (and promptly
confirmed by personal delivery, registered or certified mail or overnight
courier), sent by nationally-recognized overnight courier or sent by registered
or certified mail, postage prepaid, addressed as follows:

 
 
  If to the Company:   Vertex Pharmaceuticals Incorporated
130 Waverly Street
Cambridge, MA 02139-4242
Attn: Chief Executive Officer
with copies to:
the General Counsel; and
the Senior Vice President of Human Resources
If to the Executive:
 
at the Executive's home address listed in the Company records.

        Any such notice shall be deemed to have been given: (a) when delivered
if personally delivered or sent by facsimile on a business day; (b) on the
business day after dispatch if sent by nationally-recognized overnight courier;
and/or (c) on the fifth business day following the date of mailing if sent by
mail.

23.HEADINGS.

        The headings of the sections contained in this Agreement are for
convenience only and shall not be deemed to control or affect the meaning or
construction of any provision of this Agreement.

24.COUNTERPARTS.

        This Agreement may be executed in two or more counterparts.

25.SECTION 409A COMPLIANCE.

        It is the intention of the Company and the Executive that this Agreement
and the payments provided for herein meet the requirements of Section 409A of
the Code, to the extent applicable to this Agreement and such payments. The
Company and the Executive agree to cooperate in good faith in preparing and
executing, at such time as sufficient guidance is available under Section 409A
and from time to time thereafter, such amendments to this Agreement, if any, as
the Executive may reasonably request solely for the purpose of assuring that
this Agreement and the payments provided hereunder meet the requirements of
Section 409A. Nothing in this Section 25 shall require the Company to increase
the Executive's compensation or make the Executive whole for any requested
changes.

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26.TAX WITHHOLDING; NO GUARANTEE OF ANY TAX CONSEQUENCES.

        All payments hereunder shall be subject to all applicable withholding
for any federal, state or local income taxes including any excise taxes under
the Code. Notwithstanding any other provision of this Agreement to the contrary
or other representation, the Company does not in any way guarantee the tax
consequences of any payment or compensation under this Agreement including,
without limitation, under Section 409A of the Code.

        IN WITNESS WHEREOF, the undersigned have executed this Agreement as of
the date first written above.

    Vertex Pharmaceuticals Incorporated
 
 
/s/ Joshua S. Boger    

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Joshua S. Boger
President & Chief Executive Officer
 
 
Executive
 
 
/s/ Freda Lewis-Hall, M.D.    

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Freda Lewis-Hall, M.D.

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Exhibit 10.3