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EXHIBIT 10.35

        December 5, 2005        

VIA FEDEX

Mr. Richard C. ("Bink") Garrison
337 Marlborough Street, Apt. 3
Boston, MA 02115

RE:Vertex Pharmaceuticals Incorporated/Richard C. ("Bink") Garrison
Offer Letter

Dear Bink:

On behalf of Vertex Pharmaceuticals Incorporated (the "Company"), I am pleased
to extend an offer to you for a position with the Company as follows:

•Job Title:  Senior Vice President, Organizational Development, reporting to
Joshua Boger, Ph.D., Chairman, President & Chief Executive Officer.

•Employment Term:  Four year term commencing on December 12, 2005 (your "start
date"), terminable by either party, with or without "Cause," on thirty
(30) days' notice. Severance benefits will be available as described below.

•Duties:  As requested by the Chief Executive Officer, but generally will
include the following:

–contribute as a member of the senior management team (currently referred to as
the "Executive Team" or the "ET") which sets strategy and oversees operations
for the pharmaceutical business worldwide, and as a member of the group of
managers who coordinate the Company's functional activities worldwide (currently
referred to as the "Operating Council" or the "OC");

–develop and implement processes to increase the group effectiveness of the ET
and the OC and the individual effectiveness of each of its members;

–establish sustainable mechanisms to preserve and embed the Company's values and
culture, enhance the performance capabilities of the Company's human capital
assets, and improve the Company's ability to grow its human capital base;

–develop messages, mechanisms and modalities to enhance communication of the
Company's corporate image, mission and values, both within and outside the
Company; and

–work closely with the leaders of the human resources function, the investor
relations function, and the other functional leaders to achieve the foregoing
objectives.

•Sign-On Bonus:  You will receive a sign-on bonus in the amount of $80,000,
payable on the first regular payroll date following commencement of employment.
During the first twelve months after your start date, if you terminate your
employment or if your employment is terminated by the Company for Cause, you
will be required to repay the sign-on bonus to the Company.

•Compensation:  Annualized salary of $320,000, subject to review and adjustment
(upward) by the Company's Board of Directors as part of the normal annual senior
executive review process in effect from time to time, to be paid in accordance
with the Company's customary payroll practices.

•Initial Equity Grant:  As an important part of this offer, we will grant to you
the following initial amounts of restricted shares and stock options. These
restricted shares and stock options will be issued under, and subject to, the
general terms and conditions of the Company's 1996 Stock and Option plan.

Restricted Shares:    You will be granted restricted shares at a nominal price,
which will vest in four equal annual installments on the anniversary of your
start date. Unvested shares will be

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subject to repurchase by the Company upon termination of your employment, for a
price equal to the price for which you purchased them. The number of shares to
be issued will be calculated by dividing $200,000 by the Company's average stock
price over the ten trading days immediately prior to your start date, rounded up
to the nearest 100 shares (e.g., 9,090 shares would become 9,100).

Stock Option:    You will be granted an initial option to purchase shares of the
Company's common stock, which will vest and become exercisable with respect to
equal amounts of the underlying option stock at the end of each quarter during
the 4-year period commencing on the Start Date. The exercise price of the shares
subject to the initial stock option (the "Initial Exercise Price") will be the
average market price of the Company's shares on your start date. The number of
shares subject to the purchase option will be calculated by dividing $750,000 by
the Initial Exercise Price, rounded up to the nearest 1,000 shares (e.g., 27,300
option shares would become 28,000 option shares).

•Employment Benefits:  Major medical and dental coverage, three weeks vacation,
401(k) plan with a matching Company contribution, long term disability,
company-paid life insurance and other benefits, all as in effect from time to
time. We have previously provided you with a summary description of the benefits
currently offered by the Company. In addition, the Company will promptly
reimburse you for all business expenses reasonably incurred by you in connection
with your employment, provided that you supply receipts for or other proof of
the expenses and your claim for reimbursement is otherwise in accordance with
general Company policy.

•Participation in Bonus Program:  You will be eligible to participate in the
Company's cash bonus programs in effect from time to time and applicable to the
Company's senior executives, as determined by the Board. The Company's current
plan contemplates an annual cash bonus of up to 40% of a senior executive's
annual base salary, depending on both individual and Company performance.

•Long Term Incentive Compensation Plans:  You will be eligible to participate in
the Company's long-term incentive compensation plans, including the Company's
option and restricted stock plans, in effect from time to time and available to
the Company's senior executives, as determined by the Board.

•Change of Control Benefit:  The Company will provide you with a "change of
control" benefit on the same terms and conditions extended generally to other
senior executives. A copy of the "Change of Control Agreement" is enclosed
herewith for your review.

•Outside Interests:  The position you are being offered is for full-time
employment with the Company. We expect that your outside interests (e.g.,
directorships and similar activities) will in general contribute to your skills
and job performance at the Company and will require only reasonably amounts of
time away from the Company (as determined by the Chief Executive Officer), and
will, in all cases, be subject to prior approval by the Chief Executive Officer.

•Confidentiality and Inventions Agreement:  As a condition of your employment,
you will be required to sign a copy of our "Employee Non-Disclosure,
Non-Competition and Inventions Agreement" in the form included with this letter.

•Severance Benefits:  In the event you terminate your employment for "Good
Reason" or if your employment is terminated by the Company without "Cause"
during the during the 4-year contract term, you will receive:

(i)12 months' salary plus bonus, payable monthly in equal installments (ceasing
upon death, but in no event less than six months of benefit);

(ii)all stock options and time-vesting restricted stock held on the date of your
termination will be deemed to have been held, for vesting purposes, an
additional 18 months, and all vested options as of the termination date will
remain exercisable for 12 months; and

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(iii)continued participation in the Company's medical insurance plan until the
earlier of the end of the severance pay period specified in (i) above, or the
date you receive equivalent coverage from a subsequent employer.

•"Cause":  For purposes of the severance benefit described above, "Cause" shall
mean

(a)your conviction of a felony crime of moral turpitude;

(b)your willful refusal or failure to follow a lawful directive or instruction
of the Company's Board of Directors or the individual(s) to whom you report,
provided that you receive prior written notice of the directive(s) or
instruction(s) that you failed to follow, and provided further that the Company,
in good faith, gives you thirty (30) days to correct any problems and further
provided if you correct the problem(s) you may not be terminated for Cause in
that instance;

(c)in carrying out your duties you commit (i) willful gross negligence, or
(ii) willful gross misconduct, resulting in either case in material harm to the
Company, unless such act, or failure to act, was believed by you, in good faith,
to be in the best interests of the Company; or

(d)your violation of the Company's policies made known to you regarding
confidentiality, securities trading or inside information.

•"Good Reason":  For purposes of the severance benefit described above, "Good
Reason" shall mean that without your consent, one or more of the following
events occurs and you terminate your employment by notice in writing to the
Chief Executive Officer of the Company within 90 days after the first occurrence
of the event:

(i)You are assigned to any duties or responsibilities that are inconsistent, in
any significant respect, with the scope of duties and responsibilities currently
performed in your positions and offices as described under "Job Title" and
"Duties" above, provided that such reassignment of duties or responsibilities is
not due to your Disability or performance, nor is at your request or with your
prior agreement;

(ii)You suffer a reduction in the authorities, duties, and responsibilities
associated with your positions and offices as described under "Job Title" and
"Duties" above, on the basis of which you make a determination in good faith
that you can no longer carry out such positions or offices in the manner
contemplated at the time this Agreement was entered into, provided that such
reassignment of duties or responsibilities is not due to your Disability or your
performance, and is not at your request or with your prior agreement;

(iii)Your base salary, as determined under "Compensation" above, is decreased;

(iv)Your own office location as assigned to you by the Company is relocated
thirty-five (35) or more miles from Cambridge, Massachusetts; or

(v)Failure of any entity, in the event of a Change of Control, as defined in
your "Change of Control Agreement" referenced above, to assume all obligations
and liabilities of this Agreement.

•"Disability":  For purposes of the foregoing, a "Disability" is 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 Internal Revenue
Code Section 22(e)(3).

Although you are being hired for your particular expertise, we are counting on
the fact that the Company's management team will be highly interactive, with
people who are interested not in building and maintaining artificial barriers
around disciplines and skills, but in breaking down those barriers and applying
new insights and initiatives across related fields. The position to which you
have been hired is an important position in the Company, and we know it will be
a challenging and exciting one.

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Please note that this offer is conditional on approval of the terms and
conditions set forth herein by the Board and your ability to commence employment
with the Company on or before December 12, 2005.

Pending that approval, we are pleased to extend this offer to you and look
forward to your acceptance. Please sign and return this offer letter and the
additional documents enclosed herewith as soon as possible to indicate your
agreement with the terms of this offer. We look forward to having your
confirming response.

Once signed by you, this letter and its attachments will constitute the complete
agreement between you and the Company regarding your employment and will
supersede all prior written or oral agreements or understandings on these
matters.

We believe you will be able to make an immediate contribution to the Company's
efforts, and I think you will enjoy the rewards of working for an innovative,
fast-paced company. One of the keys to our accomplishments is good people. We
hope you accept our offer to be one of those people.

    Sincerely yours,
 
 
/s/  JOSHUA BOGER      

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Joshua Boger, Ph.D.
Chairman, President & CEO

I accept the terms of employment as described in this offer letter dated
December 5, 2005, and will start my employment on or before December 12, 2005. I
confirm that by my start date at the Company I will be under no contract or
agreement with any other entity which would in any way restrict my ability to
work at the Company or perform the functions of my job for the Company,
including, but not limited to, any employment agreement and/or non-compete
agreement.

/s/  RICHARD C. GARRISON      

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Richard C. Garrison   Date   12/6/05

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EXHIBIT 10.35