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                                                                    Exhibit 10.1

[DE LAGE LANDEN LOGO]                                                   24382127
                                                          Master Lease Agreement
                                                           VOICE: (800) 669-9441
                                                       FACSIMILE: (610) 386-5881

LESSEE
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Full Legal Name                                    Phone Number
     Virologic, Inc.                                    650-635-1100
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Carrying on Business as (If Any)                   Fax Number
                                                        650-635-1111
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Billing Address                                    Send Invoice to Attention of:
     270 East Grand Avenue
     South San Francisco CA 94080                       Accounts Payable
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                              TERMS AND CONDITIONS

     This MASTER LEASE AGREEMENT ("Agreement") is dated as of January 29, 2001
and is by and between De Lage Landen Financial Services, Inc. with offices
located at 1111 Old Eagle School Road, Wayne, Pennsylvania 19087, its successors
and assigns ("Lessor") and the above referenced lessee ("Lessee"). The parties
hereto for good and valuable consideration and intending to be legally bound
hereby agree as follows.

     1. LEASE OF SYSTEM. This Agreement establishes the general terms and
conditions under which Lessor may, from time to time, lease Systems (as
hereinafter defined) to Lessee. The terms hereof shall be deemed to form a part
of each Master Lease Schedule ("Lease") executed by the parties which references
this Agreement. "Software", "Equipment" and "Maintenance" shall mean all items
of software, equipment and maintenance set out in any Lease and shall be
collectively referred to as a "System". Lessee hereby requests Lessor to
purchase the System from the supplier(s) thereof (hereinafter called "Vendor
and/or Manufacturer", as applicable) and to lease the System to Lessee on the
terms and conditions contained herein. Each Lease shall constitute a separate
lease agreement incorporating all the terms hereof. In the event of a conflict
between the provisions of any Lease and the provisions hereof, the provisions of
the Lease shall prevail.

     The amount of the Lease Payments on each Lease ("Lease Payments") are based
upon the estimated total cost of the System on the applicable Schedule. The
Lease Payments shall be adjusted proportionately upward or downward if the
actual total cost of the System on the applicable Lease exceeds or is less than
the estimate and Lessee authorizes Lessor to adjust the Lease Payments by up to
fifteen percent (15%) in that event.

     Unless Lessor has provided Lessee with a written commitment to the
contrary, Lessee authorizes Lessor to adjust the Lease Payment on each Lease to
increase or decrease the implicit rate of the Lease Payment to the Lessor in an
amount equal to any increase or decrease in the rate of Treasury Notes with a
comparable term to the term of the Lease from the date the Lessor quoted the
Lease Rate to the date Lessor accepts the Lease.

     2. TERM AND RENT. This Agreement shall become effective upon acceptance and
execution by Lessor at its corporate offices, as specified above, and shall
remain effective at least until the expiration of the term of the last Lease
hereunder. Each Lease shall become effective upon acceptance and execution by
Lessor and shall be for the term provided therein. The term of each Lease shall
commence on the Commencement Date, as defined in the Lease with an interim term
and Base Term Commencement Date as set forth therein and shall thereafter
continue until all obligations of the Lessee under the Lease shall have been
fully performed ("Lease Term"). Interim Rent and Base Term Rent shall be due and
payable as set forth in the Lease. All payments made by or on behalf of Lessee
hereunder shall be non-refundable. LESSEE'S OBLIGATION TO PAY SUCH LEASE
PAYMENTS SHALL BE ABSOLUTE AND UNCONDITIONAL AND IS NOT SUBJECT TO ANY
ABATEMENT, SET-OFF, DEFENSE OR COUNTER-CLAIM FOR ANY REASON WHATSOEVER. All
payments hereunder shall be made to Lessor at its address specified above (or
such other place as Lessor, in writing, directs) without notice or demand
therefor. If the term of a Lease is extended, "Lease Term" shall be deemed to
refer to all extensions thereof. All provisions of this Agreement shall apply
during any extended term except as may be otherwise specifically provided in
this Agreement, in a Lease, or in any subsequent written agreement of the
parties.

     3. DELIVERY AND ACCEPTANCE. Delivery and installation arrangements and
costs, unless included in the cost of the System to Lessor and upon which the
Lease Payments were computed, are the sole responsibility of Lessee. Lessee
agrees to accept the System when delivered, installed and operating to
Manufacturer's specifications and to execute the Delivery and Acceptance
Certificate supplied by Lessor as evidence thereof. Lessee agrees to hold Lessor
harmless from specific performance of this Agreement and from damages, if for
any reason, the Vendor fails to deliver, or delays in delivery of, the System so
ordered or if the System is unsatisfactory for any reason whatsoever. Lessee
agrees that any delay in delivery of the System shall not affect the validity of
this Agreement, any Lease or the obligation to make Lease Payments thereunder.
Lessee's execution of the Delivery and Acceptance Certificate shall conclusively
establish that the System covered thereby is acceptable to Lessee for all
purposes of the Lease related thereto.

     The Lessee agrees to provide a suitable installation environment for the
System as specified in the applicable Manufacturer's manual, if any, and except
as otherwise specified by Manufacturer, to furnish all labor required for
unpacking and placing each item of System in the desired location. Without
limiting the generality of the foregoing, the foundation or floor on which the
System is to be installed, shall be in accordance with the builder's
specifications, and the power for the System shall be in accordance with the
builder's specifications and the local electrical code.

     If Lessee has entered into any purchase, licensing or maintenance
agreements with the Vendor and/or the Manufacturer ("Acquisition Agreement")
covering the System or any portion thereof, Lessee transfers and assigns to
Lessor all of Lessee's rights, but none of its obligations (except for Lessee's
obligation to pay for the System upon Lessor's acceptance of the Lease) in and
to the Acquisition Agreement, including without limitation the right to take
title to the System. IT IS HEREBY AGREED THAT LESSOR IS NOT RESPONSIBLE FOR THE
PERFORMANCE, MAINTENANCE OR SERVICING OF THE SYSTEM AND LEASES SAME "AS-IS."

     4. SELECTION OF SYSTEM AND DISCLAIMER OF WARRANTY. Lessee has selected
both the System and the Vendor and/or Manufacturer from whom Lessor covenants
to purchase the System at Lessee's request. LESSEE ACKNOWLEDGES THAT LESSOR HAS
NO EXPERTISE OR SPECIAL FAMILIARITY ABOUT OR WITH RESPECT TO THE SYSTEM. LESSEE
AGREES THAT THE SYSTEM LEASED HEREUNDER IS LEASED "AS-IS" AND IS OF A SIZE,
DESIGN AND CAPACITY SELECTED BY LESSEE AND THAT LESSEE IS SATISFIED THAT THE
SAME IS SUITABLE FOR LESSEE'S PURPOSES, AND THAT LESSOR HAS MADE NO
REPRESENTATION OR WARRANTY WITH RESPECT TO THE SUITABILITY OR DURABILITY OF
SAID SYSTEM FOR THE PURPOSES AND USES OF LESSEE, OR ANY OTHER REPRESENTATION OR
WARRANTY, EXPRESS OR IMPLIED, WITH RESPECT THERETO, INCLUDING THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. LESSOR
FURTHER DISCLAIMS ANY LIABILITY FOR LOSS, DAMAGE OR INJURY TO LESSEE OR THIRD
PARTIES AS A RESULT OF ANY DEFECTS, LATENT OR OTHERWISE, IN THE SYSTEM WHETHER
ARISING FROM THE APPLICATION OF THE LAWS OF STRICT LIABILITY OR OTHERWISE. If
the System is not properly installed, does not operate as represented or
warranted by the Vendor and/or Manufacturer or is unsatisfactory for any
reason, Lessee shall make any claim on account thereof solely against the
Vendor and/or Manufacturer and shall, nevertheless, pay Lessor all Lease
Payments under the Lease and shall not set up against Lessee's obligations any
such claims as a defense, counterclaim, set-off or otherwise. So long as Lessee
is not in breach or default of this Agreement or any Lease hereunder Lessor
hereby assigns to Lessee, solely for the purpose of making and prosecuting any
such claim any rights which Lessor may have against the Vendor and/or
Manufacturer for breach of warranty or other representation respecting any item
of the System. All proceeds of any warranty recover by Lessee from the Vendor
and/or Manufacturer of any item of the System shall first be used to repair or
replace the affected item.

     LESSEE ACKNOWLEDGES THAT NEITHER THE VENDOR NOR ANY SALESPERSON, EMPLOYEE,
REPRESENTATIVE OR AGENT OF THE VENDOR AND/OR MANUFACTURER IS AN AGENT OR
REPRESENTATIVE OF LESSOR, AND THAT NONE OF THE ABOVE IS AUTHORIZED TO WAIVE OR
ALTER ANY TERM, PROVISION OR CONDITION OF THIS AGREEMENT OR ANY LEASE HEREUNDER,
OR MAKE ANY REPRESENTATION OR WARRANTY WITH RESPECT TO THIS AGREEMENT, ANY
LEASE HEREUNDER OR THE SYSTEM LEASED HEREUNDER. Lessee further acknowledges and
agrees that Lessee, in executing this Agreement and each Lease hereunder, has
relied solely upon the terms, provisions and conditions contained herein and
therein and any other statements, warranties, or representations, if any, by the
Vendor and/or Manufacturer, or any salesperson, employee, representative or
agent of the Vendor and/or Manufacturer, have not been relied upon, and shall
not in any way affect Lessee's obligation to make the Lease Payments and
otherwise perform as set forth in this Agreement and each Lease.

     REGARDLESS OF CAUSE, LESSEE WILL NOT ASSERT ANY CLAIM WHATSOEVER AGAINST
LESSOR FOR LOSS OF ANTICIPATORY PROFITS OR ANY OTHER INDIRECT, SPECIAL OR
CONSEQUENTIAL DAMAGES, NOR SHALL LESSOR BE RESPONSIBLE FOR ANY DAMAGES OR COSTS
WHICH MAY BE ASSESSED AGAINST LESSEE IN ANY ACTION FOR INFRINGEMENT OF ANY
UNITED STATES LETTERS PATENT OR COPYRIGHT. LESSOR MAKES NO WARRANTY AS TO THE
TREATMENT OF THIS AGREEMENT OR ANY LEASE HEREUNDER FOR TAX OR ACCOUNTING
PURPOSES.

     NOTWITHSTANDING ANY PROVISION CONTAINED HEREIN TO THE CONTRARY, LESSEE
DOES NOT WAIVE ANY RIGHTS OR REMEDIES IT MAY HAVE AGAINST THE VENDOR AND/OR
MANUFACTURER OF THE SYSTEM.

     5. TITLE, PERSONAL PROPERTY AND LOCATION. The Equipment is, and shall at
all times be and remain the sole and exclusive property of Lessor, and Lessee,
notwithstanding any trade-in or down payment made by Lessee or on its behalf
with respect to the Equipment, shall have no right, title or interest therein
or thereto, except as to the use thereof subject to the terms and conditions of
this Agreement and the related Lease hereunder. To the extent that the license
for the Software ("License") allows title to Software to pass to Lessee, such
title shall vest and remain in Lessor. To the extent such vesting requires a
specific written conveyance, Lessee hereby conveys to Lessor any title it has
or may hereafter acquire in the Software and relinquishes any subsequent claim
of title in the Software, including any rights to purchase the Software and to
retain rights to use the same beyond the Lease Term. If any provision of this
paragraph requires for its effectiveness Licensor's prior written consent
because the License limits transfers, encumbrance or assignment of the
Software, then Lessee shall assist Lessor, if so requested, in obtaining such
consent.

     Lessee will not directly or indirectly create, incur, assume or suffer to
exist any lien on or with respect to the System or Lessor's title thereto,
except such liens as may arise through the independent acts or omissions of the
Lessor. Lessee, at its own expense, will promptly pay, satisfy or otherwise take
such actions as may be necessary to keep the System free and clear of any and
all such liens. The System is, and at all times shall remain, personal property
notwithstanding that the System or any item thereof may now be, or hereafter
become, in any manner affixed or attached to, or imbedded in, or permanently
resting upon real property or any improvement thereof or attached in any manner
to what is permanent. If requested by Lessor prior to or at any time during the
Lease Term, Lessee will obtain and deliver to Lessor waivers of interest or
liens in recordable form, satisfactory to Lessor, from all persons claiming any
interest in the real property on which an item of the System is installed or
located.

     The System shall be kept at the address designated in each Lease and shall
not be removed therefrom without the prior written consent of the Lessor, which
consent shall not be unreasonably withheld. Lessor may require plates or
markings to be affixed to or placed on the Equipment indicating the Lessor's
ownership of the Equipment.

     6. USE AND MAINTENANCE. Lessee shall use the System solely in the conduct
of its business and in a careful and proper manner consistent with the
requirements of all applicable insurance policies and shall only permit
qualified personnel to operate the System. Lessee will not modify the System in
any way without the prior written consent of Lessor, which consent shall not be
unreasonably withheld. Lessee shall not attach or incorporate the Equipment to
or in any other item of equipment or software in such a manner that the
Equipment becomes or may be deemed to have become an accession to or a part of
such other item of equipment or software.

     At its own expense, Lessee will cause the System to be kept, used and
maintained as recommended by the Manufacturer and Manufacturer's maintenance
manuals and plans by competent and duly qualified personnel only approved by
the Manufacturer, in accordance with applicable governmental regulations, if
any, and for business purposes only and in as good operating condition as when
delivered to Lessee hereunder, ordinary wear and tear resulting from proper use
alone excepted, and will provide all maintenance and service and make all
repairs or replacements reasonably necessary for such purpose. Lessee shall
record in a log book all maintenance and repair performed on the System and
deliver the same to Lessor from time to time as requested by Lessor and upon
termination of the Lease.

     If any parts or accessories forming part of the System become worn out,
lost, destroyed, damaged beyond repair or otherwise permanently rendered unfit
for use, Lessee, at its own expense, shall within a reasonable time cause such
parts or accessories to be replaced by replacement parts or accessories which
are free and clear of all liens, encumbrances or rights of others and have a
utility at least equal to the parts or accessories replaced. All equipment,
software accessories, upgrades, parts and replacements for or which are added
to or become attached to the System, which are essential to the operation of
the System or which cannot be detached from the System without materially
interfering with the operation of the System or adversely affecting the value
and utility which the System would have had without the addition thereof, shall
immediately become the property of Lessor, and shall be deemed incorporated in
the System and subject to the terms of this Agreement and the related Lease as
if originally leased hereunder. Lessee shall not make any material alterations
to the System without the prior written consent of Lessor, which consent shall
not be unreasonably withheld.

     Upon reasonable advance notice, Lessor shall have the right to inspect the
System, log book and all other maintenance records with respect thereto, if
any, at any reasonable time during normal business hours.

     In the event the Lease Payments include the cost of maintenance and/or
service being provided by Vendor and/or Manufacturer, Lessee acknowledges that
Lessor is not responsible for providing any required maintenance and/or service
for the System. Lessee shall make all claims for service and/or maintenance
solely to the Vendor and/or Manufacturer and Lessee's obligation to make all
required Lease Payments shall remain unconditional.





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     7.   ASSIGNMENT. LESSEE MAY NOT ASSIGN THIS AGREEMENT, ANY LEASE OR THE
RIGHTS HEREUNDER, NOR SHALL THE LESSEE SUBLEASE OR LEND THE SYSTEM OR SUBMIT IT
TO BE USED BY ANYONE OTHER THAN LESSEE'S EMPLOYEES WITHOUT THE PRIOR WRITTEN
CONSENT OF LESSOR, WHICH CONSENT SHALL NOT BE UNREASONABLY WITHHELD.  Lessor may
at any time assign all or part of any interest in this Agreement or any Lease
and in each item of the System and monies to become due to Lessor hereunder,
and, Lessor may grant security interests in the System, subject to the Lessee's
rights therein. In such events, all the provisions of this Agreement or any
Lease hereunder for the benefit of Lessor shall inure to the benefit of and be
exercised by or on behalf of such assignee, but the assignee shall not be liable
for or be required to perform any of Lessor's obligations to Lessee. The Lessor
may direct that all Lease Payments due and to become due under this Agreement or
any Lease hereunder and assigned by Lessor shall be paid directly to assignee,
upon notice of such assignment to Lessee. The right of the assignee to the
payment of the assigned Lease Payments, the performance of all Lessee's
obligations and to exercise any other of Lessor's rights hereunder shall not be
subject to any defense, counterclaim or set-off which the Lessee may have or
assert against the Lessor, and the Lessee hereby agrees that it will not assert
any such defenses, set-offs, counterclaims and claims against the assignee. No
such assignment by Lessor shall relieve Lessor of its obligations or limit or
otherwise affect Lessee's rights and/or obligations hereunder.

     8.   RETURN OF SYSTEM, STORAGE.  The Lessee shall, at its sole expense,
surrender each item of the System then subject to any Lease hereunder at the
expiration or earlier termination of the Lease Term by delivering the item to
the Lessor at a location accessible by common carrier and designated by the
Lessor within the Continental United States or, if specified by the Lessor, into
the custody of a carrier designated by the Lessor. In the case of Software,
Lessee shall destroy all intangible items constituting such Software and shall
deliver to Lessor all tangible items constituting such Software. At Lessor's
request, Lessee shall also certify in a form acceptable to Lessor that (i)
Lessee has complied with the above Software return provisions, (ii) Lessee will
not use the Software after the expiration or earlier termination of the Lease
Term, and (iii) Lessee shall permit Lessor and/or the Vendor of the Software to
inspect Lessee's locations to verify compliance with the terms hereof.

     If the item of the System is delivered into the custody of a carrier, the
Lessee shall arrange for the shipping of the item and its insurance in transit
in accordance with the Lessor's instructions and at the Lessee's sole expense.
The Lessee, at its sole expense, shall completely sever and disconnect the
System from the Lessee's property, all without liability of the Lessor to the
Lessee, or to any person claiming through or under the Lessee, for damage or
loss caused by such severance and disconnection. The Lessee, at its sole
expense, shall pack or crate the System or its component parts carefully and in
accordance with any recommendations of the Manufacturer with respect to similar
new software or equipment before surrendering the System to the Lessor. The
Lessee shall deliver to the Lessor the plans, specifications, operation manuals
and other warranties and documents furnished by the Manufacturer or Vendor of
the System and such other documents in the Lessee's possession relating to the
maintenance and methods of operation of such System.

     When an item of Software or Equipment is surrendered to the Lessor it
shall be in the condition and repair required to be maintained under this
Agreement. It will also be free of all evidence of advertising or insignia
placed on it by the Lessee and meet all legal and regulatory conditions
necessary for the Lessor to sell or lease it to a third party and be free of
all liens. If Lessor reasonably determines that an item of Software or
Equipment, once it is returned, is not in the condition required hereby, Lessor
may cause the repair, service, upgrade, modification or overhaul of the item of
Software or Equipment to achieve such condition and upon demand, Lessee shall
promptly reimburse Lessor for all amounts reasonably expended in connection
with the foregoing.

     Should Lessee not return the System at the end of the Lease Term, Lessee
shall continue to make Lease Payments to Lessor in the sum equal to the last
Lease Payment and at the same intervals as set out in the Lease as a
month-to-month lease term (or other term as designated by Lessor) until
returned by Lessee or until returned upon demand therefor by Lessor. The
acceptance of said Lease Payments by Lessor shall not waive Lessor's right to
have the System promptly returned to lessor pursuant to the provisions hereof,
nor shall the acceptance of said Lease Payments be deemed to be an extension of
the Lease Term.

     Upon written request of the Lessor, the Lessee shall provide free storage
for any item of System for a period not to exceed 60 days after expiration of
its Lease Term before returning it to the Lessor. The Lessee shall arrange for
the insurance described to continue in full force and effect with respect to
such item during its storage period and the Lessor shall reimburse the Lessee
on demand for the incremental premium cost of providing such insurance.

     9.   LOSS OR DAMAGE. Lessee hereby assumes and shall bear the entire risk
of loss (including theft, requisition of use, erasure or inoperability) or
destruction of or damage to the System from any and every cause whatsoever,
whether or not insured, until the System is returned to Lessor. No such loss or
damage shall relieve Lessee from any obligation under this Agreement or any
Lease hereunder, which shall continue in full force and effect. In the event of
damage to or loss or destruction of the System (or any item thereof), Lessee
shall promptly notify Lessor in writing of such fact and shall, at the option of
Lessor, (a) place the same in good repair, condition and working order, (b)
replace the Software and/or Equipment with like Software and/or Equipment in
good repair, condition and working order, acceptable to Lessor and transfer
clear title to or a right to use, as appropriate, such Software and/or
replacement Equipment to Lessor, whereupon such Software and/or Equipment shall
be subject to the Lease and be deemed the System to purposes hereof, or (c) on
the due date for the next Lease Payment or upon the expiration of the Lease,
whichever first occurs, pay to Lessor: (i) the Stipulated Loss Value therefor as
may be specified in the Lease plus all Lease Payments then due, or if the Lease
does not provide for Stipulated Loss Values, (ii) the present value of the total
of all unpaid Lease Payments for the entire Lease Term plus the estimated fair
market value of the System at the end of the originally scheduled Lease Term or
the agreed upon purchase option price, if any, all of which shall be discounted
to the date of payment by Lessee at an annual rate equal to the lesser of six
percent (6%) or the rate then available for United States Treasury obligations
having an average life equal to the remaining Lease Term ("Present Value Rate"),
whereupon the Lease shall terminate with respect thereto. All proceeds of
insurance received by Lessor as a result of such loss or damage shall, where
applicable, be applied toward the replacement or repair of the System or the
payment of the obligations of Lessee hereunder.

     10.   INSURANCE. Prior to the Lease Commencement Date, Lessee shall obtain,
maintain and keep the System insured against all risks of loss or damage from
every cause whatsoever including, without limitation, loss by fire, theft,
"mysterious disappearance", collision, earthquake, flood and such other risks of
loss as are customarily insured against on the type of System leased hereunder
by businesses of the type in which Lessee is engaged, in an amount not less than
the replacement cost or Stipulated Loss Value of the System, whichever is
greater, without deductible and without co-insurance. Lessee shall maintain such
insurance coverage for the entire Lease Term. Lessee shall also obtain and
maintain for the entire Lease Term, comprehensive public liability insurance
covering liability for bodily injury, including death, and property damage
resulting from the purchase, ownership, leasing, maintenance, use, operation or
return of the System with a combined single limit of not less than Two Million
Dollars ($2,000,000.00) per occurrence. If Lessee is a doctor, hospital or other
health care provider, Lessee shall furnish Lessor with evidence of sufficient
professional liability insurance. All said insurance shall be in a form and an
amount and with companies reasonably satisfactory to Lessor. Lessor, its
successors or assigns, shall be the sole named loss payee with respect to
insurance for damage to or loss of the System and shall be named as an
additional insured on the public liability insurance. Lessee shall pay all
premiums for such insurance and shall deliver to Lessor the original policy or
policies of insurance, certificates of insurance, or other evidence satisfactory
to Lessor evidencing the insurance required thereby, along with proof,
satisfactory to Lessor, of the payment of the premiums for such insurance
policies. All insurance shall provide for at least sixty (60) days advance
written notice to Lessor before any cancellation, expiration or material
modification thereof and also provide that no act or default of any person other
than Lessor, its agents or those claiming under Lessor, will affect Lessor's
right to recover under such policy or policies in case of loss. Lessee hereby
irrevocably appoints Lessor as Lessee's attorney-in-fact (which power shall be
deemed coupled with an interest) to make claim for, receive payment of, and
execute and endorse all documents checks or drafts received in payment for loss
or damage under any such insurance policy. Unless Lessee is in default, Lessee
may with the prior written approval of Lessor, settle and adjust all such
claims. Lessee agrees if Lessee shall fail to procure, maintain, and pay for
such insurance, Lessor shall have the right, but not the obligation, to obtain
such insurance on behalf of and at the expense of Lessee. In the event Lessor
does obtain such insurance, Lessee agrees to pay all costs thereof with the next
Lease Payment or as specified by Lessor.

     11.   WAIVER AND INDEMNITY. Lessee assumes and agrees to indemnify, defend
and keep harmless Lessor, its agents and employees, from and against any and all
losses, damages, injuries, claims, demands and expenses, including legal,
consulting and expert expenses (other than such as may directly and proximately
result from the gross negligence or willful misconduct of Lessor, its agents or
employees), arising on account of the ordering (whether by Acquisition Agreement
or otherwise), acquisition, delivery, installation or rejection of the System,
the possession, maintenance, use, condition (including without limitation,
latent and other defects and whether or not discoverable by Lessor or Lessee,
any claim in tort for strict liability, and any claim for patent, trademark or
copyright infringement) or operation of any item of the System, and by
whomsoever used or operated, during the Lease Term with respect to that item of
the System, the loss, damage, destruction, environmental impact, removal,
return, surrender, sale or other disposition of the System, or any item thereof.
Lessor shall give Lessee prompt notice of any claim or liability hereby
indemnified against Lessee shall be entitled to control the defense thereof, so
long as Lessee is not in Default hereunder; provided, however, that Lessor shall
have the right to approve defense counsel selected by Lessee. The obligations
contained in this paragraph continue beyond the termination of the Lease if the
liability occurred during the Lease Term.

     12. EVENTS OF DEFAULT. The term "Event of Default" shall mean any one or
more of the following:

     (a) Lessee shall fail to make any Lease Payment, or any other payment, as
it becomes due and such failure is not cured within 10 days; or

     (b) Lessee shall fail to perform or observe any of the covenants set forth
in Paragraph 10; or

     (c) Lessee shall fail to perform or observe any other covenant, condition
or agreement to be performed or observed by it hereunder or in any Lease and
such failure is not cured within 30 days after the date of notice thereof by
Lessor to Lessee; or

     (d) Lessee shall enter into any transaction of merger or consolidation in
which it is not the surviving entity or sell, transfer or otherwise dispose of
all or substantially all of its assets ("Assets") unless the surviving entity or
the entity acquiring such Assets assumes all the duties and obligations of
Lessee hereunder and which merger, consolidation, sale or transfer must be
approved in writing by Lessor; or

     (e) (i) Lessee or any guarantor of Lessee's obligations hereunder
("Guarantor") shall commence any action (A) for relief under any existing or
future law of any jurisdiction, domestic or foreign, relating to bankruptcy,
insolvency, reorganization or relief of debtors, or (B) seeking appointment of
a receiver, custodian or other similar official for it or for its Assets or
making a general assignment for the benefit of its creditors; or (ii) there
shall be commenced against Lessee any action (A) of a nature referred to in
clause (i) which results in the entry of an order for relief or any such other
relief and remains undismissed or undischarged for a period of 30 days, or (B)
seeking attachment, execution or similar process against its assets which
results in the entry of an order for any such relief which shall not be vacated
or discharged within 30 days from the entry thereof; or (iii) Lessee shall
generally not, or be unable to, pay its debts as they come due; or

     (f) Lessee or any Guarantor shall die or (if an entity) liquidate or
dissolve itself or be liquidated or terminated; or

     (g) Any representation or warranty made by Lessee herein or otherwise
furnished Lessor in connection with this Agreement or any Lease hereunder shall
prove at any time to have been untrue or misleading in any material respect; or

     (h) Lessee or any Guarantor defaults on any indebtedness for borrowed
money, lease, or installment sale obligation, in each case when any applicable
grace period for such obligation has expired and the lender, lessor or creditor
has commenced to exercise any remedy, but only if the indebtedness or other
obligation is in an amount equal to or in excess of $50,000; or

     (i) Lessor shall reasonably deem itself insecure as a result of a material
adverse change in Lessee's financial condition or operations:

     (j) Lessee shall default in its obligations under a License

     13.   REMEDIES. Upon the occurrence of any Event of default, Lessor may
declare this Agreement or any Lease hereunder to be in default and exercise any
one or more of the following remedies.

     (a) Declare the entire unpaid balance of Lease Payments for the unexpired
term of the Lease hereunder immediately due and payable and similarly accelerate
the balances due under any other Leases between Lessor and Lessee without notice
or demand, (b) Sue for and recover all Lease Payments and other monies due and
to become due under the Lease hereunder, plus the estimated fair market value of
the System at the end of the originally scheduled Lease Term or any agreed upon
Purchase Option, all of which shall be discounted to the date of default at the
Present Value Rate (defined in Section 9 hereof), but only to the extent
permitted by law, (c) Charge Lessee interest on all monies due Lessor at the
rate of eighteen percent (18%) per annum from the date of default until paid but
in no event more than the maximum rate permitted by law, (d) Require Lessee to
assemble all Equipment and Software at Lessee's expense, at a place reasonably
designated by Lessor, (e) Remove any physical obstructions for removal of the
Equipment from the place where the Equipment is located and take possession of
any or all items of System, without demand or notice, wherever same may be
located, disconnecting and separating all such items of the System from any
other property, with or without any court order or pre-taking hearing or other
process of law, it being understood that facility of repossession in the event
of default is a basis for the financial accommodation reflected by this
Agreement or any Lease hereunder. Lessee hereby waives any and all damages
occasioned by such retaking except such damages as may be caused by Lessor's
gross negligence or willful misconduct. Lessor may, at its option, use, ship,
store or repair any or all items of the System so removed and shall sell, lease
or otherwise dispose of any such System at a private or public sale. Lessor may
expose the System and resell or lease the System at Lessee's premises at
reasonable business hours without being required to remove the System. In the
event Lessor disposes of the System, Lessor shall give Lessee credit for any
sums received by Lessor from the sale or lease of the System after deduction of
the expenses of sale or lease. The credit for any sums to be received by Lessor
from such lease during the remaining portion of the Lease Term shall be
discounted to the commencement date of such lease at an annual rate equal to the
implicit rate of interest of such lease. Lessee shall also be liable for and
shall pay to Lessor (i) all expenses incurred by Lessor in connection with the
enforcement of any of Lessor's remedies, including all expenses of repossessing,
storing, shipping, repairing and selling the System, and (ii) Lessor's
reasonable attorney's fees. Lessor and Lessee acknowledge the difficulty in
establishing a value for the unexpired Lease Term and owing to such difficulty
agree that the provisions of this paragraph represent an agreed measure of
damages and are not to be deemed a forfeiture or penalty.

     In the case of Software, it is acknowledged and agreed that the
unauthorized use, disclosure or transfer of the Software could cause Lessor
incalculable and irreparable harm. Therefore, if Lessee is found to be using
(in whatever manner) any portion of the Software after the applicable Lease
Term or after an Event of Default and Lessor's written demand for Lessee to
return the Software or if the licensor of the Software terminates a License or
Lessee's right to use the Software thereunder, then liquidated damages shall
immediately be payable to Lessor in an amount equal to two (2) times the
license fees paid or payable with respect to the Software being used.

     Whenever any payment is not made by Lessee when due hereunder, Lessee
agrees to pay to Lessor, not later than one month thereafter, an amount
calculated at the rate of five cents per one dollar for each such delayed
payment as compensation for Lessor's internal operating expenses arising as a
result of such delayed payment, but only to the extent permitted by law. Such
amount shall be payable in addition to all amounts payable by Lessee as a
result of the exercise of any of the remedies herein provided.

     All remedies of Lessor hereunder are cumulative, are in addition to any
other remedies provided for by law, and may, to the extent permitted by law, be
exercised concurrently or separately. The exercise of any one remedy shall not
be deemed to be an election of such remedy or to preclude the exercise of any
other remedy. No failure on the part of the Lessor to exercise and no delay in





<PAGE>   3
exercising any right or remedy shall operate as a waiver thereof or modify the
terms of this Agreement or any Lease hereunder. A waiver of default shall
not be a waiver of any other or subsequent default. Lessor's recovery hereunder
shall in no event exceed the maximum recovery permitted by law.

     14. LAWS, REGULATIONS AND TAXES. Lessee shall comply with all laws,
regulations and orders relating or pertaining to the System, this Agreement or
any Lease hereunder and Lessee shall be responsible for, as and when due, and
shall indemnify and hold Lessor harmless from and against all present and
future taxes and other governmental charges, or any increases therein
(including, without limitation, sales, use, leasing and stamp taxes and license
and registration fees) and amounts in lieu of such taxes and charges and any
penalties or interest on any of the foregoing, imposed, levied upon, in
connection with, or as a result of the purchase, ownership, delivery, leasing,
possession or use of the System, or based upon or measured by the Lease
Payments or receipt with respect to this Agreement or any Lease hereunder.
Lessee shall not, however, be obligated to pay any taxes on or measured by
Lessor's net income. Lessee authorizes Lessor to add to the amount of each
Lease Payment any sales use or leasing tax that may be imposed on or measured
by such Lease Payment. Lessee shall pay Lessor on demand, as additional rent,
the amount of the personal property tax required to be paid by Lessor as owner
of the System, plus reasonable costs incurred in collecting and administering
any taxes, assessments or fees and remitting them to the appropriate authorities
and interest thereon at the highest legal rate allowed, from the date due until
fully paid. In the event Lessee does not pay all sums specified above, Lessor
has the right, but not the obligation, to pay the same. If Lessor shall so pay
any of the aforementioned then the Lessee shall remit such amount with the next
Lease Payment plus Lessor's reasonable costs incurred in collecting and
administering any taxes, assessments or fees and remitting them to the
appropriate authorities.

     15. UCC FILINGS AND FINANCIAL STATEMENTS. Lessee authorizes Lessor to file
a financing statement with respect to the System signed only by the Lessor
where permitted by the Uniform Commercial Code or other applicable law. Lessee
hereby appoints Lessor as Lessee's attorney-in-fact to execute such financing
statement on Lessee's behalf and to do all acts or things which Lessor may deem
necessary to protect Lessor's title and interest hereunder. Lessor and Lessee
further agree that a carbon, photographic or other reproduction of this
Agreement or any Lease hereunder may be filed as a financing statement and
shall be sufficient as a financing statement under the Uniform Commercial Code
or other applicable law. It is the intent of the parties that this is a true
lease, and the filing of a financing statement under the Uniform Commercial
Code or other applicable law shall not be construed as evidence that any
security interest was intended to be created, but only to give public notice of
Lessor's ownership of the System. If this Agreement or any Lease hereunder is
deemed at any time to be one intended as security then Lessee grants Lessor a
security interest in the System and the proceeds from the sale, lease or other
disposition of the System. Lessee agrees to pay Lessor a fee to reimburse
Lessor's expenses for the preparation and filing of all such financing
statements as Lessor may reasonably deem necessary and for Lessor's other
documentation costs.

     Lessee agrees to submit financial statements or tax returns if its
financial statements are unaudited within 90 days from the end of its fiscal
year and Lessee warrants to Lessor that all financial statements furnished and
to be furnished have been and will be prepared in accordance with generally
accepted accounting principles, are an accurate reflection of Lessee's
financial condition and that there has been no material adverse change in the
financial condition of Lessee or any guarantor of Lessee's obligations since
the dates of preparation and submission of the financial statements submitted
to Lessor. Lessee agrees to deliver to Lessor at any time or times hereafter
such information or documents, including, without limitation, certified
resolutions, financial statements and legal opinions, as Lessor may request.

     16. SECURITY DEPOSIT. Lessor shall retain any security deposit set forth
on each Lease as security for the performance by Lessee of its obligations
hereunder. Any security deposit so taken shall be non-interest bearing. Lessor
may, but shall not be obligated to, apply any security deposit to cure any
Event of Default hereunder, in which event Lessee shall promptly restore any
amount so applied. If Lessee is not in default in any of Lessee's obligations
hereunder, any security deposit will be returned to Lessee at the termination of
the Lease related thereto. Lessee hereby grants to Lessor a security interest in
the cash comprising the security deposit from time to time together with the
proceeds thereof to secure the prompt performance as and when due of all
obligations of Lessee hereunder.

     17. LESSEE REPRESENTATIONS AND WARRANTIES. Lessee hereby represents,
warrants and covenants to Lessor the following with respect to each Lease as of
the date Lessee executes the Delivery and Acceptance Receipt related thereto;
(a) Lessee is organized and validly existing under the laws of the state of its
organization, with adequate power and capacity to enter into the Lease, all
documents related to the purchase of the System and any other documents
required to be delivered in connection with the Lease or the System
(hereinafter "Documents") and is duly qualified to do business wherever
necessary to carry on its present business, including all states where the
System is to be located; (b) the Documents have been duly authorized, executed
and delivered by Lessee and constitute valid, legal and binding agreements,
enforceable in accordance with their terms, except to the extent that the
enforcement of remedies therein provided may be limited under applicable
bankruptcy and insolvency laws; (c) no approval, consent or withholding of
objections is required from any federal, state or local governmental authority
or instrumentality with respect to the entry into or performance by Lessee of
the Documents, except such as have already been obtained, (d) the entry into
and performance by Lessee of its obligations under the Documents will not (i)
violate any judgment, order, law or regulation applicable to Lessee or (ii)
result in any breach of, constitute a default under or result in the creation
of any lien charge, security interest or other encumbrance upon any item of the
System pursuant to any indenture, mortgage, deed of trust, bank loan or credit
agreement or other instrument (other than the Lease or any purchase money
security interest retained by any supplier) to which Lessee is a party; (e)
there are no suits or proceedings pending or threatened in court or before any
regulatory commission, board or other administrative governmental agency
against or affecting Lessee, which will have a material adverse effect on the
ability of Lessee to fulfill its obligations under the Lease; and (f) the
balance sheet and statement of income of Lessee, or of any consolidated group
of which Lessee is a member, heretofore delivered to Lessor have been prepared
in accordance with generally accepted accounting principles and fairly present
the financial position of Lessee or the consolidated group of companies of
which Lessee is a member on and as of the date thereof and the results of its
or their operations for the period or periods covered thereby. Since the date
of such balance sheet and statement of income there has been no material
adverse change in the financial or operating condition of Lessee or of its
consolidated group; (g) Lessee has conducted a review of its significant
vendor's computer systems to identify those areas that could be affected by the
"Year 2000" issue and has developed and implemented a plan to resolve the issue
and make its operations "Year 2000" compliant prior to January 1, 2000 and the
"Year 2000" issue and the costs of resolving such issue will not materially
adversely affect its financial condition, business or operations prior to
January 1, 2000. "Year 2000" issue shall mean the failure of computer systems
to in any way utilize data and information due to the occurrence of the year
2000 or the inclusion of dates on or after January 1, 2000.

     18. MISCELLANEOUS. All obligations of the Lessee if more than one, shall
be joint and several. All paragraph headings are inserted for reference
purposes only and shall not affect the interpretation or meaning of this
Agreement or any Lease hereunder. Lessee agrees to execute or obtain and
deliver to Lessor at Lessor's request such additional documents as Lessor may
reasonably deem necessary to protect Lessor's interest in the System, this
Agreement and any Lease.

     19. NOTICE. Written notices to be given hereunder shall be deemed to have
been given when delivered personally or deposited in the United States mails,
postage prepaid, addressed to such party at its address set forth above or at
such other address as such party may have subsequently provided in writing.

     20. SUPPLIER'S CONTRACT. Lessor and Lessee agree that each Lease is a
Finance Lease as that term is defined in Article 2A of the Uniform Commercial
Code. Lessee acknowledges that Lessor has apprised Lessee of the identity of
the System supplier. Lessor hereby notifies Lessee that Lessee may have rights
pursuant to the contract with the supplier and the Lessee may contact the
supplier for a description of any rights or warranties that Lessee may have
under this contract.

     21. LESSEE'S WAIVERS. Lessee hereby waives any and all rights and remedies
granted Lessee by Sections 508 through 522 of Article 2A of the Uniform
Commercial Code including, by way of example only and not as a limitation, the
right to repudiate any Lease and reject the System; the right to cancel any
Lease; the right to revoke acceptance of the System; the right to grant a
security interest in the System in Lessee's possession and control for any
reason; the right to recover damages thereunder for any breach of warranty or
for any other reason deduct all or any part of the claimed damages resulting
from Lessor's default, if any, under any Lease; the right to accept partial
delivery of the System; the right to "cover" by making any purchase or leases
of or contract to purchase or lease System in substitution for those due from
Lessor; the right to recover any general, special, incidental or consequential
damages, for any reason whatsoever; and the right to specific performance,
replevin, detinue, sequestration, claim and delivery and the like for the
System. The waivers contained herein shall not constitute a waiver by Lessee of
any of its rights or remedies against the Vendor and/or Manufacturer of the
System.

     22. CHOICE OF LAW. This Agreement and each Lease hereunder shall be
binding and effective when accepted by Lessor at its corporate office in Wayne,
Pennsylvania, shall be deemed to have been made in Wayne, Pennsylvania and,
except for local filing requirements and laws relating to conflict of laws,
shall be governed by and construed in accordance with the laws of the
Commonwealth of Pennsylvania. Lessee hereby consents to and agrees that
personal jurisdiction over Lessee and subject matter jurisdiction over the
System shall be with the courts of the Commonwealth of Pennsylvania or the
Federal District Court for the Eastern District of Pennsylvania, solely at
Lessor's option, with respect to any provision of this Agreement or any Lease
hereunder. Lessee agrees that service of process in any action or proceeding
may be duly effected upon Lessee by mailing such process via certified mail,
return receipt requested. Lessee also agrees to waive its right to a trial by
jury.

     23. ENTIRE AGREEMENT, NON-WAIVER AND SEVERABILITY. This Agreement and each
Lease hereunder contain the entire agreement and understanding between Lessee
and Lessor relating to the subject matter of each Lease. No agreements or
understandings shall be binding on the parties hereto unless set forth in
writing and signed by the parties. Time is of the essence in this Agreement and
each Lease hereunder. No waiver by Lessor of any breach or default shall
constitute a waiver of any additional or subsequent breach or default by Lessor
nor shall it be a waiver of any of Lessor's rights. Any provision of this
Agreement or any Lease hereunder which for any reason may be held unenforceable
in any one jurisdiction shall, as to such jurisdiction, be ineffective to the
extent of such unenforceability without invalidating the remaining provisions
of this Agreement or any Lease hereunder, and any such unenforceability in any
one jurisdiction shall not render such provision unenforceable in any other
jurisdiction.

     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed by their authorized representatives as of the date first above
written.



     You agree to all of the Terms and Conditions contained in this Agreement,
and in any attachments to same (all of which are included by reference) and
become part of this Agreement. You acknowledge to have read and agreed to all
the Terms and Conditions and understand that the Leases are non-cancelable for
the full term shown therein. This Agreement shall not be binding upon Lessor or
become effective unless and until Lessor executes the Agreement. The Equipment
subject to this Agreement and the Leases is not for home or personal use.

LESSEE SIGNATURE

/s/ KAREN WILSON
------------------------------------------------------------
Signature

1/29/01
------------------------------------------------------------
Date

Karen Wilson
------------------------------------------------------------
Print Name

CFO
------------------------------------------------------------
Title

Virologic, Inc.
------------------------------------------------------------
For                 Legal Name of Corporation or Partnership

    (AGREEMENT MUST BE SIGNED BY AUTHORIZED OFFICER, PARTNER OR PROPRIETOR)


LESSOR

Lessor Signature                   Date

/s/ [Signature Illegible]               3/6/01
------------------------------------------------------------
Print Name

------------------------------------------------------------
Title

------------------------------------------------------------
For
     DE LAGE LANDEN FINANCIAL SERVICES, INC.
------------------------------------------------------------
Lease Number
               24382127
------------------------------------------------------------
Vendor ID Number

------------------------------------------------------------





<PAGE>   4


--------------------------------------------------------------------------------
MASTER LEASE SCHEDULE NO. 01
--------------------------------------------------------------------------------

This Master Lease Schedule No. 01 ("Lease") is by and between De Lage Landen
Financial Services, Inc. ("Lessor") and Virologic, Inc. ("Lessee") and
incorporates the terms and conditions of that certain Master Lease Agreement
dated as of January 29, 2001 between Lessor and Lessee ("Master Lease"). Lessor
hereby leases to Lessee and Lessee hereby leases from Lessor the following
described items of Equipment for the Lease Term and on terms and conditions set
forth herein. The Lease shall become effective as against Lessor upon Lessor's
execution hereof.

<TABLE>
<CAPTION>
--------------------------------------------------------------------------------
1. EQUIPMENT: (see Attachment A)
--------------------------------------------------------------------------------
  EQUIPMENT LOCATION:                        BILLING ADDRESS:
--------------------------------------------------------------------------------
  <S>                                        <C>
  345 Oyster Point                           270 East Grand Avenue
  So. S F CA 94080                           South San Francisco, CA 94080
--------------------------------------------------------------------------------
Phone #: Same                               Phone #: 650-635-1100
--------------------------------------------------------------------------------
</TABLE>

2. LEASE TERM:

The Lease shall commence on the day that Lessee executes a Delivery and
Acceptance Certificate with respect to the Equipment ("Commencement Date"). The
Base Lease Term of the Lease shall be for the term indicated below and shall
commence on either the first or the fifteenth day of the month following the
Commencement Date, according to Lessor's standard procedures ("Base Term
Commencement Date").

(a)  Base Lease Term: 36 months.

--------------------------------------------------------------------------------

3. LEASE PAYMENTS:

(a) Interim Rent is due and payable in full on the date specified in Lessor's
invoice(s) therefor and shall be computed by dividing one payment of Base Term
Rent by thirty (30) and multiplying the result by the number of days from and
including the Commencement Date to the day preceding the Base Term Commencement
Date.

(b)  Base Term Rent consists of:

<TABLE>
<CAPTION>
--------------------------------------------------------------------------------
     Number                 Amount                 Taxes           Total
--------------------------------------------------------------------------------
     <S>                   <C>                    <C>            <C>
      1-36                 $8,529.27              $682.34        $9,211.61
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
</TABLE>

Frequency of Base Term Rent:
--------------------------------------------------------------------------------
Monthly   x  Quarterly        Other
--------------------------------------------------------------------------------

The first installment of Base Term Rent shall be due and payable upon the
earlier of (i) the date specified in Lessor's invoice therefor, or (ii) Base
Term Commencement Date.

--------------------------------------------------------------------------------

4. SPECIAL PAYMENTS:

The following Special Payment(s) shall be due and payable on the date Lessee
executes this Lease.

<TABLE>
<CAPTION>
--------------------------------------------------------------------------------
  Security Deposit   Advance Lease Payment          Other                Total
--------------------------------------------------------------------------------
<S>                  <C>                  <C>                       <C>
                       $9,211.61          $32.400.00 ($30,000.00 +  $41,611.61
                                              $2,400.00 - taxes)
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
</TABLE>
<PAGE>   5



5.   STIPULATED LOSS VALUES: (NONE)

6.   STANDARDS FOR USE AND MAINTENANCE: (SEE MASTER LEASE)

7.   STANDARDS FOR RETURN CONDITION: (SEE MASTER LEASE)

8.   LEASE END OPTION:

PROVIDED NO EVENT OF DEFAULT SHALL HAVE OCCURRED AND REMAIN UNCURED, LESSEE MAY
UPON THE EXPIRATION OF THE LEASE TERM EXERCISE ANY ONE OF THE FOLLOWING OPTIONS
WITH RESPECT TO NOT LESS THAN ALL ITEMS OF EQUIPMENT LEASED HEREUNDER, (i)
RETURN THE EQUIPMENT TO LESSOR, (ii) EXTEND THE LEASE TERM AT THE THEN FAIR
RENTAL VALUE ("FAIR RENTAL VALUE") FOR AN EXTENSION TERM THE LENGTH OF WHICH
SHALL BE DETERMINED BY AGREEMENT BETWEEN LESSEE AND LESSOR OR (iii) PURCHASE
THE EQUIPMENT FOR A CASH PRICE EQUAL TO $1.00 ("CASH PRICE"). IF LESSEE ELECTS
TO PURCHASE THE EQUIPMENT AND UPON RECEIPT BY LESSOR OF THE CASH PRICE AND ALL
OTHER SUMS DUE HEREUNDER, LESSOR SHALL CONVEY TITLE TO THE EQUIPMENT TO LESSEE
FREE OF LIENS AND ENCUMBRANCES CREATED BY LESSOR ON AN AS-IS, WHERE-IS BASIS AND
WITHOUT WARRANTY.

9.   ADDITIONAL PROVISIONS: (NONE)

10.  MODIFICATIONS AND WAIVERS, EXECUTION IN COUNTERPARTS:

TO THE EXTENT ANY OF THE TERMS AND CONDITIONS SET FORTH IN THIS LEASE CONFLICT
WITH OR ARE INCONSISTENT WITH THE MASTER LEASE, THIS LEASE SHALL GOVERN AND
CONTROL. NO AMENDMENT, MODIFICATION OR WAIVER OF THIS LEASE WILL BE EFFECTIVE
UNLESS EVIDENCED BY A WRITTEN DOCUMENT SIGNED BY BOTH PARTIES. THIS LEASE MAY
BE EXECUTED IN COUNTERPARTS, ALL OF WHICH WHEN TAKEN TOGETHER SHALL CONSTITUTE
ONE AND THE SAME INSTRUMENT.

IN WITNESS WHEREOF, THE PARTIES HERETO HAVE CAUSED THIS MASTER LEASE SCHEDULE
TO BE EXECUTED AND DELIVERED BY THEIR DULY AUTHORIZED REPRESENTATIVES AS OF
THE DATES SET FORTH BELOW.

LESSEE: VIROLOGIC, INC.                LESSOR: DE LAGE LANDEN FINANCIAL
                                               SERVICES, INC.

BY: /s/ BILL YOUNG                     BY: /s/ [Signature Illegible]

PRINT NAME: Bill Young

TITLE: CEO

DATE: 1/29/01


BY: /s/ KAREN WILSON

PRINT NAME: Karen Wilson

TITLE: CFO

DATE: 1/29/01


                              FOR OFFICE USE ONLY

                    LEASE NO.

                    CUSTOMER NO.

                    COMMENCEMENT DATE:

                    BASE TERM COMMENCEMENT DATE




<PAGE>   6
ATTACHMENT A -- EQUIPMENT DESCRIPTION

Attachment forming part of Master Lease Schedule No. 01 by and between De Lage
Landen Financial Services, Inc. ("Lessor") and Virologic, Inc. ("Lessee").

===============================================================================

Equipment Description:

As described on quotation #20111713






<TABLE>
<S>                                       <C>
        LESSEE SIGNATURE                         ACCEPTED BY LESSOR

                                                                   3/6/01

By: /s/ BILL YOUNG                         By: /s/ [Signature Illegible]
    ---------------------------

Print Name: BILL YOUNG

Title:  CEO

Date:  1/29/01


By: /s/ KAREN WILSON
    ---------------------------

Print Name: Karen Wilson

Title:  CFO

Date:  1/29/01

</TABLE>







<PAGE>   7
[APPLIED BIOSYSTEMS LETTERHEAD]
[LOGO]

                                                                       QUOTATION

To:  Ken Hitchner                       QUOTE NO.:          20111713
     VIROLOGIC                          QUOTE VALID TO:     03/30/2001
     270 East Grand Avenue              QUOTE DATE:         01/19/2001
     SOUTH SAN FRANCISCO CA 94080       PAY. TERMS:         Net 30 Days
                                        FREIGHT TERMS:      FOB FACTORY - FRT
                                                            QUOTED

TELEPHONE NO.   650-866-7424
FAX NO.         650-635-1111
YOUR REFERENCE

<TABLE>
<S>            <C>                                <C>     <C>            <C>
4308058        3700 DNA ANALYZER SEQUENCING       1.00    $ 300,000.00   $300,000.00

</TABLE>

          INCLUDES:

          Sequencing Analysis Software
          Manual & Chemistry Guide
          Chemistry Kit
          Installation/On Site Training
          Start-Up Chemical Kit
          Data Collection Software (includes polymer & calibration standards)
          NT Workstation, Monitor, Keyboard
          User Documentation
          LIMITED WARRANTY:
          One year parts, labor and service travel (Analyzer)
          90 days on parts (software and Reagents)

          NOTE:  The above price includes the TWO Capillary Arrays listed below.




THIS QUOTATION IS SUBJECT TO THE FOLLOWING TERMS AND CONDITIONS:

1.   Orders are FOB Foster City unless otherwise indicated and are subject to
     acceptance only at seller's plant at Foster City, California.

2.   Stenographical and clerical errors on the face of this form are subject to
     correction.

3.   Seller shall not be liable for any delay in performance of any order
     accepted by it or in delivery or shipment of material thereunder when such
     delay is directly or indirectly caused by or in any manner arises or
     results from fire, flood, accident, riot, war, governmental interference,
     rationing, allocations, embargoes, or strikes.

4.   In the case of discrepancy most recent quotation date will supersede all
     prior quotations.

5.   All amounts given in USD.

SALES REPRESENTATIVE Ted Young
PREPARED BY   Caglan Baler



ACCEPTANCE OF THIS QUOTATION IS LIMITED TO THE ATTACHED TERMS






<PAGE>   8
                        [APPLIED BIOSYSTEMS LETTERHEAD]

                                                                       QUOTATION

                                              QUOTE NO.:          20111713
                                              QUOTE VALID TO:     03/30/2001
                                              QUOTE DATE:         01/19/2001

To: Ken Hitchner
    Virologic

<TABLE>
<CAPTION>
================================================================================================
MATERIAL NO.         DESCRIPTION                          QTY/EA        UNIT PRICE        TOTAL
================================================================================================
<S>                  <C>                                  <C>           <C>             <C>
4305787              FG, ARRAY CAPILLARY 110 x 50cm         2.00        $     0.00      $  0.00

                     - Used for Long Read Sequencing or High Resolution GeneScan.
                         List price is $2,800.00 each.

                     The above instrument includes a choice of POP Polymer listed below.

4306733              FG, BTL,3700 DNA ANALYSIS POLYMER      2.00        $   365.00      $730.00

4313087              FG, BTL,3700 POP-5                     2.00        $   365.00      $730.00


                     Freight charges are prepaid and invoiced for $350.00
                     Typical lead time after receipt of purchase order is 5 weeks.

                     To expedite processing your purchase order, please
                     fax the order referencing the quotation number to
                     attention of Sales Administration -- Fax 650-638-5875.
</TABLE>