Exhibit 10.27.2

CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION
PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED.

THIRD AMENDMENT TO LEASE

THIS THIRD AMENDMENT TO LEASE ("Amendment") is made and entered into as of the 28th day of November 2003,
by and between CATELLUS DEVELOPMENT CORPORATION, a Delaware corporation ("Landlord"), and ALLOS THERAPEUTICS, INC., a Delaware corporation
("Tenant").

RECITALS:

A.    Landlord
and Tenant entered into that certain Office Lease dated as of April 4, 2001 (the "Original Lease"), as
amended by that certain First Amendment to Lease and Commencement Date Memorandum dated as of November 1, 2002 ("First Amendment"), that certain
Second Amendment to Lease dated November 12, 2002 ("Second Amendment"), and that certain Amended and Restated Second Amendment to Lease dated
December 9, 2002 ("Restated Second Amendment"), whereby Tenant leased certain office space in the building located at 11080 CirclePoint Road in
Westminster, Colorado. The Original Lease, as amended by the First Amendment, Second Amendment and Restated Second Amendment, is referred to herein as the
"Lease."

B.    By
this Amendment, Landlord and Tenant desire to expand the Premises and to otherwise modify the Lease as provided herein.

C.    Unless
otherwise defined herein, capitalized terms as used herein shall have the same meanings as given thereto in the Lease.

NOW,
THEREFORE, in consideration of the foregoing recitals and the mutual covenants contained herein, and for other good and valuable consideration, the receipt and sufficiency of which
are hereby acknowledged, the parties hereto agree as follows:

AGREEMENT:

1.The Existing Premises.Landlord currently leases to Tenant that certain office space containing 43,377
rentable square feet located on the ground and second (2nd) floors of the Building (the "Existing Premises").

2.Expansion of the Premises.That certain space located on the ground floor of the Building consisting of
approximately 579 rentable square feet, as outlined on the floor plan attached hereto asExhibit Aand made a part hereof, is referred to
herein as the "Expansion Space." Tenant shall lease the Expansion Space effective as of March 1, 2004 (the "Expansion
Commencement Date"). Accordingly, effective upon the Expansion Commencement Date, the Existing Premises shall be increased to include the Expansion Space. Such addition of the
Expansion Space to the Existing Premises shall, effective as of the Expansion Commencement Date, increase the number of rentable square feet leased by Tenant in the Building to a total of 43,956
rentable square feet, subject to verification pursuant to Section 3 below. Effective as of the Expansion Commencement Date, all references in the Lease to the "Premises" shall mean and refer to
the Existing Premises as expanded by the Expansion Space. The period from the Expansion Commencement Date through the Expiration Date is referred to herein as the "Expansion
Term".

3.Verification of Rentable Square Footage.The rentable square footage of the Expansion Space shall be subject
to verification in accordance with the provisions of Section 2.1 of the Original Lease,

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except
that Landlord shall cause its space measurement consultant to provide such verification within thirty (30) days following the Expansion Commencement Date. If such verification results in
a rentable square footage of the Expansion Space that is different than that set forth in Section 2 above, then the parties shall further amend the Lease to modify all amounts, percentages and
figures appearing or referred to in this Amendment to conform to such corrected rentable square footage (including, without limitation, the Base Rent, and Tenant's Percentage Share and the TI
Allowance).

4.Base Rent.During the Expansion Term, and in addition to the Base Rent for the Existing Premises, Tenant
shall pay Base Rent for the Expansion Space as follows (although Base Rent for the Existing Premises and the Expansion Space are separately identified, such amounts shall be a single and
non-severable rental obligation):

Period of
Expansion Term

Annual Base Rent Per
Rentable Square Foot

Annual Base Rent

Monthly Base Rent[*]

[*]

[*]

[*][*]

[*]

[*]

[*][*]

[*]

[*]

[*]


CERTAIN
CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO
RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED.

5.Tenant's Percentage Share.Commencing on July 1, 2003, and continuing thereafter during the Expansion
Term, Tenant's Percentage Share shall be increased to 29.10%.

6.Exclusion of Variable Operating Expenses.Operating Expenses attributable to the Expansion Space shall
exclude those Operating Expenses that vary with occupancy, such as janitorial expenses and utility costs (other than those attributable to the Common Facilities), until the Tenant Improvements (as
defined inExhibit B) are substantially completed in all or any portion of the Expansion Space.

7.Tenant Improvements.The Tenant Improvements (as defined in Exhibit B) in the Expansion Space shall be installed and
constructed in accordance with the terms of the Tenant Work Letter attached hereto asExhibit Band made a part hereof. The parties acknowledge that there is no required time schedule to construct the Tenant Improvements, and
Tenant shall, subject to Landlord's reasonable approval, be entitled to designate when the Tenant Improvements are to be constructed. Tenant acknowledges that
construction of the Tenant Improvements may occur during the Expansion Term and that the performance of such work shall not be deemed a constructive eviction nor shall Tenant be entitled to any
abatement of Rent in connection therewith. In addition, Landlord shall not be liable for any damage to property, injury to persons or damage to Tenant's business caused by the construction of the
Tenant Improvements during the Expansion Term.

8.Parking.During the Expansion Term, Tenant shall rent from Landlord an additional two (2) parking
spaces for use in the Building's parking facility. Tenant's rental and use of such additional parking spaces shall be in accordance with, and subject to, all provisions of Section 2.4 of the
Original Lease.

9.Brokers.Each party represents and warrants to the other that no broker, agent or finder negotiated or was
instrumental in negotiating or consummating this Amendment other than Equis Corporation and CB Richard Ellis ("Brokers"). Landlord shall pay a brokerage
commission to Brokers in accordance with separate agreements between and Landlord and Brokers. Subject to the foregoing, each party agrees to defend, indemnify and hold harmless the other party from
and against any claim for a commission or finder's fee by any person or entity who claims or alleges that they were retained or engaged by the indemnifying party or at the request of such party in
connection with this Amendment.

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10.Tenant Representations.Each person executing this Amendment on behalf of Tenant represents and warrants to
Landlord that, and Tenant shall, at Landlord's request, provide Landlord with evidence that: (a) Tenant has full right and authority to enter into this Amendment and to perform all of Tenant's
obligations hereunder; and (b) each person signing this Amendment on behalf of Tenant is duly and validly authorized to do so.

11.No Further Modification.Except as set forth in this Amendment, all of the terms and provisions of the Lease
shall apply with respect to the Expansion Space and shall remain unmodified and in full force and effect. Effective as of the date hereof, all references to the
"Lease" shall refer to the Lease as amended by this Amendment.

IN
WITNESS WHEREOF, this Amendment has been executed as of the day and year first above written.

| |  | "Landlord":                                             
| |  | --------------------------------------------------------
| |  | CATELLUS DEVELOPMENT CORPORATION,
a Delaware corporation
| |  | By:                                                     
| |  |                                                         
| |  | "Tenant":                                               
| |  | ALLOS THERAPEUTICS, INC.,
a Delaware corporation        
| |  | By:                                                     
| |  | By:                                                     

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EXHIBIT A

OUTLINE OF EXPANSION SPACE

[Graphic]

A-1

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EXHIBIT B

CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION
PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED.

TENANT WORK LETTER

This Work Letter ("Work Letter") is attached to the Amendment as Exhibit Band
incorporated into the Amendment by reference. Capitalized terms used herein and not defined herein shall have the respective
meanings set forth in the Lease.

1.Landlord's Work.Landlord has constructed the Building in accordance with the plans and specifications
described in Schedule 1 attached hereto.

2.Tenant Improvements.



B-1

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B-2

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B-3

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B-4

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3.Completion of the Tenant Improvements.



B-5

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B-6

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SCHEDULE 1 TO EXHIBIT B

BUILDING PLANS AND SPECIFICATIONS

WESTMINSTER
BASE BUILDING CORE AND SHELL

|Parking Stalls:         |  | Parking is provided at 4.1 spaces per 1,000 square feet of rentable building area.                                                                                                                                                                                                                                                                                                                                                 
|----------------------- |  | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|Parking Lot Lighting:   |  | Parking lot lighting is provided, designed to supply an average to minimum ratio of approximately 1.0 foot candles/SF.                                                                                                                                                                                                                                                                                                             
|Sitework:               |  | Asphalt concrete paving in all traffic and parking areas, concrete curb and gutter per approved development plans.                                                                                                                                                                                                                                                                                                                 
|Landscaping:            |  | Landscape planting materials and irrigation of all planting areas per approved development plans.                                                                                                                                                                                                                                                                                                                                  
|Building Structure:     |  | Precast concrete frame with precast concrete floor and roof structure and approximately 4-inch concrete topping slab.                                                                                                                                                                                                                                                                                                              
|Floor Loading Criteria: |  | Live load is approximately 50 psf in general office area, with approximately 100 psf at corridor and interior office area immediately adjacent to corridor. Partition load is approximately 20 psf.                                                                                                                                                                                                                                
|Ceiling Heights:        |  | Clear ceiling heights are approximately 12'-2" feet at ground floor tenant areas, and approximately 9'-2" at floors 2, 3, 4 and 5 tenant areas. Typical structure to structure clearance is approximately 14.5 feet at ground floor
14'-8" from floor to bottom of "T" at ground floor, and 11'-8" approximately 11.5 feet from floor to bottom of "T" at floors 2, 3, 4 and 5. Clearances may be 12 inches less at beam locations.
|Building Skin:          |  | Precast architectural concrete spandrel panels with continuous glazing in between. Full height glazing at most locations. See elevation drawings for detail.                                                                                                                                                                                                                                                                       
|Roofing:                |  | 60 mil EPDM roof membrane, ballasted, over 2.6" rigid polyisocyanruate board. R-value of 19.                                                                                                                                                                                                                                                                                                                                       
|Perimeter Walls:        |  | Perimeter, exterior walls to be insulated only, no drywall.                                                                                                                                                                                                                                                                                                                                                                        
|Core Service Areas:     |  | 1.                                                                                                                                                                                                                                                                                                                                                                                                                                 
|                        |  | 2.                                                                                                                                                                                                                                                                                                                                                                                                                                 
|                        |  | 3.                                                                                                                                                                                                                                                                                                                                                                                                                                 
|                        |  | 4.                                                                                                                                                                                                                                                                                                                                                                                                                                 
|                        |  | 5.                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Rest Rooms:             |  | Rest rooms to have ceramic tile on floors, and full height on wet walls. Toilet partitions to be ceiling hung stainless steel. Vanity tops to be granite. Restrooms to be ADA compliant.                                                                                                                                                                                                                                           
|Shower Facilities:      |  | Ground floor restrooms to include two shower stalls each in men's and women's. One shower stall in each to be ADA compliant.                                                                                                                                                                                                                                                                                                       
|                        |  |                                                                                                                                                                                                                                                                                                                                                                                                                                    

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|Telephone Room:     |  | Main telephone/fiber optic room provided at ground floor, approximately 20 feet by 10 feet. Conduit to be stubbed into room for telephone and 3 possible fiber optic providers. Approximately 6 foot by 9 foot communications
rooms provided on floors 2, 3, 4 and 5.                                                                                                                                                                                             
|------------------- |  | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|Elevators:          |  | Hydraulic elevators, 3,500 lb. capacity provided. Interior cab height to be approximately 10 feet, with suspended ceiling at approximately 9 feet. Finishes will be compatible with main lobby. Freight elevator to be supplied with
protective blankets. Waiting time will be average of 27-29 seconds, with 5 minute handling capacity of 13% of building population (upper floors only). Elevators to be ADA compliant, and provided with emergency telephones.
|Fire Protection:    |  | Complete fire sprinkler system in accordance with applicable codes for office occupancy. Fireproofing of the Building's structural steel as specified on the structural plans for the Building as approved by the City of Westminster (a copy of which
plans Tenant acknowledges receiving).                                                                                                                                                                      
|Plumbing Systems:   |  | Complete plumbing system for domestic water service, sanitary sewer service, and roof drainage. Water and sanitary systems will be accessible to tenant areas for future connections for convenience sinks and other uses.                                                                                                                                                                                                                                        
|HVAC:               |  | HVAC system is provided with rooftop units, total capacity approximately 460 tons, of approximately 350 sf per ton. Primary trunk ducts and exterior zone VAV boxes provided at approximately 1 per 1,100 SF. Exterior zone VAV boxes
are provided with electric reheat. No distribution ducting or diffusers are included at these exterior zone boxes.                                                                                                          
|                    |  | Energy management system provided, with remote computer monitoring capability. Tenant metering capability also included in system.                                                                                                                                                                                                                                                                                                                                
|                    |  | HVAC Design criteria for cooling load allowed include the following:                                                                                                                                                                                                                                                                                                                                                                                              
|                    |  | 2 watts per SF for lighting;
1.5 watts per SF for office equipment
150 SF per person.                                                                                                                                                                                                                                                                                                                                                                             
|Electrical Service: |  | The building is provided with primary electrical service, 277/480 volts, 3 phase, with main disconnects in the main electrical room on the first floor. Electrical distribution panel rooms are provided two per floor adjacent to
stairwells.                                                                                                                                                                                                                    
|                    |  | Electrical service will provide total capacity of 27 watts per square foot, generally allocated as follows:                                                                                                                                                                                                                                                                                                                                                       
|                    |  | 15 watts per SF for HVAC loads;
3 watts per SF for lighting;
6.5 watts per SF for tenant equipment loads;
2.5 watts per SF spare power;
A pad area for a future generator to be included in the building shell.                                                                                                                                                                                                                                                   
|Fire Alarm:         |  | Fire alarm panel is provided, including fire alarm devices as required by code in core and common areas.                                                                                                                                                                                                                                                                                                                                                          
|Security:           |  | A card access system to be provided at the main entry doors of the building. Elevator card access also to be available based on tenant needs (but at Tenant's sole cost and expense).                                                                                                                                                                                                                                                                             

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