Antigenics To Report Second Quarter 2008 Financial Results On July 31, 2008; Conference Call To Follow

NEW YORK — July 24, 2008 — Antigenics Inc. (NASDAQ: AGEN) will release its second quarter financial results before the market opens on July 31, 2008.

Antigenics executives will host a conference call at 11:00 a.m. ET that same day. To access the live call, dial 877.762.5772 (domestic) or 706.643.6986 (international); the access code is 55836270. The call will also be webcast and will be accessible from the company’s website at www.antigenics.com/webcast/. A replay will be available approximately two hours after the call through midnight ET on August 14, 2008. The replay number is 800.642.1687 (domestic) or 706.645.9291 (international), and the access code is 55836270. The replay will also be available on the company’s website approximately two hours after the live call.

Antigenics is a biotechnology company developing treatments for cancers and infectious diseases. For more information, please visit www.antigenics.com.