Exhibit 4.6

PER.CX COLLABORATION and LICENSE AGREEMENT    CRUCELL HOLLAND B.V.AVENTIS PASTEUR S.A



WHEREAS, AvP is a leading manufacturer in the field of human vaccines and other related immunological products for prevention, treatment,
and cure of diseases in humans and has extensive worldwide research, development, manufacturing, and marketing operations in that field.

WHEREAS, CRUCELL has expertise in the field of creating producer cell lines and has developed and owns patents and know how in the field
of producer cell lines and more specifically has created and owns rights in a producer cell line suitable for use in propagation of influenza viruses (the "PER.C6" cell line).

WHEREAS, CRUCELL has made, under a material transfer agreement (April 24, 2001), the PER.C6 cell line available to AvP
for evaluation in its laboratories for the manufacture of influenza virus.

WHEREAS, CRUCELL and AvP signed a Research Collaboration and License Agreement on January 24, 2003 for the creation of a new
Ad5E1-HER cell line (PER.C8), and the development of a cell based influenza vaccine to be manufactured with PER.C8, and wherein AVP elected not to license the PER.C6 cell line, at that
time, but AvP preserved it's opportunity to access the PER.C6 cell line if, for any reason, the PER.C8 development is not successful, by receiving from CRUCELL certain rights of first refusal and
first negotiation to the PER.C6 cell line.

WHEREASAvP has decided to accelerate its development plans for cell based influenza vaccines, and desires to use CRUCELL's
PER.C6 cell line technology for the manufacture, development and commercialization of its cell based influenza vaccine.

AND WHEREASCRUCELL and AvP have agreed to collaborate in the development and commercialization of a PER.C6-based influenza
vaccine.

NOW, THEREFORE, in consideration of the mutual covenants and promises set forth herein, the Parties, intending to be legally bound, agree
as follows:

1    DEFINITIONS

Plural used in this Agreement shall mean singular and vice versa.

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2    STEERING COMMITTEE

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3    DEVELOPMENT PROGRAM





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4    DEVELOPMENT PROGRAM PLANS AND BUDGETS AND FUNDING

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5    REGULATORY AFFAIRS

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6    REPORTS AND RECORDS

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7    COMMERCIALIZATION COLLABORATION

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8    MANUFACTURING

9    GRANT OF LICENSES, THIRD PARTY RIGHTS AND COVENANTS

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10    PAYMENTS FOR GRANTED RIGHTS AND MILESTONES

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11    ROYALTIES

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12    PAYMENTS; BOOKS AND RECORDS

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13    INTELLECTUAL PROPERTY

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14    REPRESENTATIONS AND WARRANTIES

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15    CONFIDENTIALITY

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16    INDEMNIFICATION

17    TERM AND TERMINATION

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18    MISCELLANEOUS

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|To CRUCELL: |  | CRUCELL
Archimedesweg 4,
2333CN Leiden
THE NETHERLANDS
Attn. Business Development
|----------- |  | ---------------------------------------------------------------------------------
|To AvP:     |  | Aventis Pasteur
2, avenue Pont Pasteur,
69007, Lyon,
France
Attn. CEO,           
|            |  | With a copy to General Counsel                                                   
|            |  | Legal Department
Aventis Pasteur
Discovery Drive
Swiftwater, PA 18370            



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IN
WITNESS WHEREOF, the Parties hereto have executed this Agreement to be effective as of the date the last Party to undersign.

|AVENTIS PASTEUR S.A.                             |  | CRUCELL HOLLAND B.V.                           
|------------------------------------------------ |  | -----------------------------------------------
|By                                               |  | /s/ David J. Williams                          
|                                                 |  |                                                
|Name: David J. Williams
Title: President and CEO |  | Domenico Valerio, Ph.D.
Chief Executive Officer

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