Edgar Filing: ANTIGENICS INC /DE/

ANTIGENICS INC.

Date: May 27, 2009

/s/ Garo H. Armen

Garo H. Armen

Chairman and CEO

424(b)(3)

Filed Pursuant to Rule 424(b)(3) and Rule 424(c)

Registration No. 333-156556

May 27, 2009

PROSPECTUS SUPPLEMENT NO. 7

5,929,212 SHARES OF COMMON STOCK

ANTIGENICS INC.

This prospectus supplement amends the prospectus dated March 18, 2009 (as supplemented on April 15, 2009, April 17, 2009, April 22, 2009, April 27, 2009, May 4, 2009, and May 11, 2009) that relates to the issuance of up to 5,929,212 shares of our common stock, par value $0.01 per share (“common stock”), issuable upon the conversion of 5,250 shares of Series B2 Convertible Preferred Stock, par value $0.01 per share (“Series B2 Convertible Preferred Stock”). If the shares of Series B2 Convertible Preferred Stock are converted through payment of cash consideration, if at all, we will receive the cash from such conversion.

This prospectus supplement is being filed to include the information set forth in the Current Report on Form 8-K filed on May 27, 2009, which is set forth below. This prospectus supplement should be read in conjunction with the prospectus dated March 18, 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, and Prospectus Supplement No. 6 dated May 11, 2009, 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 May 22, 2009, the last reported closing price per share of our common stock was $0.62 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. 7 IS MAY 27, 2009

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

May 23, 2009

Date of Report (Date of earliest event reported)

ANTIGENICS 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 1.01

Entry into a material definitive agreement

On May 23, 2009, Antigenics Inc. (“Antigenics”) executed a binding letter of intent with ISSI – Strategy (“ISSI”) pursuant to which the parties agreed that ISSI would be Antigenics exclusive distributor for Antigenics’ autologous cancer vaccine, Oncophage^® in the Russian Federation. Pursuant to the terms of the letter, ISSI would also provide related import/export and logistics management and commercialization services. The initial term of the arrangement is three years, unless extended or earlier terminated by the parties in accordance with the terms of the letter.

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.