424(b)(3)

Filed Pursuant to Rule 424(b)(3) and Rule 424(c)
Registration No. 333-149116

December 12, 2011

PROSPECTUS SUPPLEMENT NO. 53

17,417,434 SHARES OF COMMON STOCK

AGENUS INC.

This prospectus supplement amends the prospectus dated March 16, 2009 (as supplemented on April 15, 2009, April 17, 2009, April 22, 2009, April 27, 2009, May 4, 2009, May 11, 2009, May 27, 2009, June 4, 2009, June 8, 2009, June 9, 2009, June 11, 2009, June 15, 2009, July 7, 2009, July 15, 2009, August 3, 2009, August 5, 2009, September 11, 2009, September 18, 2009, November 12, 2009, January 5, 2010, March 1, 2010, March 25, 2010, April 26, 2010, May 11, 2010, May 18, 2010, July 23, 2010, August 9, 2010, August 25, 2010, November 3, 2010, November 10, 2010, December 30, 2010, January 7, 2011, January 14, 2011, January 28, 2011, March 1, 2011, March 8, 2011, March 18, 2011, April 18, 2011, May 5, 2011, May 9, 2011, June 8, 2011, June 17, 2011, August 8, 2011, August 16, 2011, September 7, 2011, September 27, 2011, September 30, 2011, October 11, 2011, October 20, 2011, November 7, 2011, and November 17, 2011) to allow certain stockholders or their pledgees, donees, transferees, or other successors in interest (the “Selling Stockholders”), to sell, from time to time, up to 8,708,717 shares of our common stock, which they have acquired in a private placement in the United States, and up to 8,708,717 shares of our common stock issuable upon the exercise of warrants which are held by the Selling Stockholders named in the prospectus.

We would not receive any proceeds from any such sale of these shares. To the extent any of the warrants are exercised for cash, if at all, we will receive the exercise price for those warrants.

This prospectus supplement is being filed to include the information set forth in the Current Report on Form 8-K filed on December 12, 2011, which is set forth below. This prospectus supplement should be read in conjunction with the prospectus dated March 16, 2009, Prospectus Supplement No. 1 dated April 15, 2009, Prospectus Supplement No. 2 dated April 17, 2009, Prospectus Supplement No. 3 dated April 22, 2009, Prospectus Supplement No. 4 dated April 27, 2009, Prospectus Supplement No. 5 dated May 4, 2009, Prospectus Supplement No. 6 dated May 11, 2009, Prospectus Supplement No. 7 dated May 27, 2009, Prospectus Supplement No. 8 dated June 4, 2009, Prospectus Supplement No. 9 dated June 8, 2009, Prospectus Supplement No. 10 dated June 9, 2009, Prospectus Supplement No. 11 dated June 11, 2009, Prospectus Supplement No. 12 dated June 15, 2009, Prospectus Supplement No. 13 dated July 7, 2009, Prospectus Supplement No. 14 dated July 15, 2009, Prospectus Supplement No. 15 dated August 3, 2009, Prospectus Supplement No. 16 dated August 5, 2009, Prospectus Supplement No. 17 dated September 11, 2009, Prospectus Supplement No. 18 dated September 18, 2009, Prospectus Supplement No. 19 dated November 12, 2009, Prospectus Supplement No. 20 dated January 5, 2010, Prospectus Supplement No. 21 dated March 1, 2010, Prospectus Supplement No. 23 dated March 25, 2010, Prospectus Supplement No. 24 dated April 26, 2010, Prospectus Supplement No. 25 dated May 11, 2010, Prospectus Supplement No. 26 dated May 18, 2010, Prospectus Supplement No. 27 dated July 23, 2010, Prospectus Supplement No. 28 dated August 9, 2010, Prospectus Supplement No. 29 dated August 25, 2010, Prospectus Supplement No. 30 dated November 3, 2010, Prospectus Supplement No. 31 dated November 10, 2010, Prospectus Supplement No. 32 dated December 30, 2010, Prospectus Supplement No. 33 dated January 7, 2011, Prospectus Supplement No. 34 dated January 14, 2011, Prospectus Supplement No. 35 dated January 28, 2011, Prospectus Supplement No. 36 dated March 1, 2011, Prospectus Supplement No. 37 dated March 8, 2011, Prospectus Supplement No. 38 dated March 18, 2011, Prospectus Supplement No. 39 dated April 18, 2011, Prospectus Supplement No. 40 dated May 5, 2011, Prospectus Supplement No. 41 dated May 9, 2011, Prospectus Supplement No. 42 dated June 8, 2011, Prospectus Supplement No. 43 dated June 17, 2011, Prospectus Supplement No. 44 dated August 8, 2011, Prospectus Supplement No. 45 dated August 16, 2011, Prospectus Supplement No. 46 dated September 7, 2011, Prospectus Supplement No. 47 dated September 27, 2011, Prospectus Supplement No. 48 dated September 30, 2011, Prospectus Supplement No. 49 dated October 11, 2011, Prospectus Supplement No. 50 dated October 20, 2011, Prospectus Supplement No. 51 dated November 7, 2011, and Prospectus Supplement No. 52 dated November 17, 2011, which are to be delivered with this prospectus supplement.

Our common stock is quoted on The NASDAQ Capital Market (“NASDAQ”) under the ticker symbol “AGEN.” On December 8, 2011, the last reported closing price per share of our common stock was $2.30 per share.

Investing in our securities involves a high degree of risk. Before investing in any of our securities, you should read the discussion of material risks in investing in our common stock. See “Risk Factors” on page 1 of the prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

THE DATE OF THIS PROSPECTUS SUPPLEMENT NO. 53 IS DECEMBER 12, 2011


 

 

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

 

 

FORM 8-K

 

 

CURRENT REPORT

Pursuant to Section 13 or 15(d) of

the Securities Exchange Act of 1934

December 8, 2011

Date of Report (Date of earliest event reported)

 

 

AGENUS INC.

(Exact name of registrant as specified in its charter)

 

 

 

DELAWARE   000-29089   06-1562417

(State or other jurisdiction

of incorporation)

 

(Commission

File Number)

 

(IRS Employer

Identification No.)

3 Forbes Road

Lexington, MA

  02421
(Address of principal executive offices)   (Zip Code)

781-674-4400

(Registrant’s telephone number, including area code)

 

 

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

 

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

 

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

 

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

 

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

 

 

 


Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On December 8, 2011, in line with the on-going cost containment efforts and current size and operations of Agenus Inc. (the Company), the Company’s Board of Directors (the “Board”) has decided to fix its size at five members. As such, effective December 8, 2011, the Board has been reduced from seven members to five with the resignation of Mr. John Hatsopoulos and Mr. Timothy Rothwell.


SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

 

    AGENUS INC.
Date: December 12, 2011     By:   /s/    Garo H. Armen        
      Garo H. Armen
      Chairman & CEO