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Pharmexa Provides Update on the HeptoVax Trial of GV1001 In Liver Cancer

Summary: Pharmexa updates on preliminary results of the HeptoVax trial after the first 21 patients. Final data is still expected before the end of the second quarter of 2008.

HORSOLM, Denmark, Nov. 19, 2007-As stipulated in the clinical trial protocol, the clinical investigators and Pharmexa reviewed the interim safety and efficacy data from the first 21 patients enrolled in the HeptoVax trial, an uncontrolled Phase II trial in which GV1001 (a telomerase peptide vaccine administered with GM-CSF) was given to patients suffering from advanced hepatocellular carcinoma (HCC or liver cancer). As previously announced, Pharmexa provides an update of the trial at this point in time.

Enrollment of patients to the trial, which takes place in three centers in Spain, France and Germany, has been completed. Currently, 14 patients are still on treatment with GV1001. According to plan, the final trial results will include an analysis of safety, immunogenicity, tumor response, time-to-progression and survival of all 40 patients enrolled. As planned, these data are expected to be available before the end of the second quarter of 2008.

In the first 21 patients, all 6 vaccine doses were well tolerated and no vaccine-attributable serious adverse effects were observed. No measurable tumor responses were observed in the first 21 patients. Important T-cell immune response data and overall survival data are not yet available. The observed lack of an objective tumor response as measured by CT scans in this small cohort of patients with advanced liver cancer was not surprising and does not exclude that patients will experience other treatment benefits. For example, a recently concluded placebo-controlled controlled Phase III trial of the new cancer drug sorafenib (Nexavar®) demonstrated partial tumor responses in only 7 out of 299 treated patients (2.3%), but still gave significant improvements in time-to-progression and survival.

Achim Kaufhold, Pharmexa's CSO and CMO says: "The HeptoVax trial is progressing according to plan and will deliver conclusive results within the time frame we originally announced. We are looking forward to the in-depth analysis of the final data set concerning, safety, immunogenicity, objective tumor responses, time-to-progression and survival, which will determine whether or not we proceed to further development in this particular indication."

HeptoVax trial design outline In the open, uncontrolled trial, 40 patients with advanced stage liver cancer will receive a single pre-treatment dose of the chemotherapeutic drug cyclophosphamide three days prior to the start of immunotherapy, followed by doses of GV1001 plus GM-CSF three times in the first week, and once weekly in week 2, 3, 4 and 6. Thereafter, GV1001 plus GM-CSF will be given once a month. All patients will be treated for a minimum of 6 months unless they show symptomatic progression, in which case patients will be discontinued from the trial.

The primary outcome variable of the trial is to assess tumor efficacy, measured by objective tumor response. Other endpoints include the safety and immunogenecity of the vaccine. Approximately half of the patients with advance stage liver cancer are expected to die within a year, hence other efficacy parameters such as time-to-progression and overall survival will also be measured.

Liver cancer represents a large unmet need Hepatocellular carcinoma is the fifth most common cancer in the world. More than 600,000 new cases of HCC occur worldwide each year with almost as many deaths. In Europe alone, more than 50,000 new cases occur each year. The incidence of HCC, however, varies greatly between different countries and regions, and HCC occurs significantly more often in Japan than in Europe. Moreover, accumulating evidence indicates that the incidence of liver cancer is rising. HCC is twice as common in men as in women and has a strong association with hepatitis B and hepatitis C infection as well as with cirrhosis.

The GV1001 vaccine GV1001 is a so called peptide vaccine that activates the patients' immune system - primarily the T-cells - to recognize and kill cancer cells. GV1001 differs from most other peptide vaccines by containing epitopes that can stimulate both the immune system's T-helper cells, which coordinate the immune response and killer T-cells which selectively attack cancer cells. GV1001 is targeted towards an enzyme called telomerase. Telomerase is rarely found in normal cells, but is overexpressed in most cancer cells, which makes telomerase a good target for a cancer vaccine. In addition, telomerase activity is a key factor in the process wherein cancer cells lose their normal mortality, which is a common feature for all cancers. GV1001 therefore has the potential to be a universal cancer vaccine and Pharmexa's broad development strategy for GV1001 reflects this. More details can be found on Pharmexa's homepage.

Hørsholm, November 19, 2007

Jakob Schmidt Chief Executive Officer

Additional information: Jakob Schmidt, Chief Executive Officer, telephone +45 4516 2525 Claude Mikkelsen, Vice President, Corporate Affairs and Communication, telephone +45 4516 2525 or +45 4060 2558

Note to editors: Pharmexa A/S is a leading company in the field of active immunotherapy and vaccines for the treatment of cancer, serious chronic and infectious diseases. Pharmexa's proprietary technology platforms are broadly applicable, allowing the company to address critical targets in cancer and chronic diseases, as well as serious infectious diseases such as HIV, influenza, hepatitis and malaria. Its leading programs are GV1001, a peptide vaccine that has entered phase III trials in pancreatic cancer and phase II trials in liver cancer, and HIV and hepatitis vaccines in phase I/II. Collaborative agreements include H. Lundbeck, Innogenetics, IDM Pharma and Bavarian Nordic. With operations in Denmark, Norway and USA, Pharmexa employs approximately 105 people and is listed on the Copenhagen Stock Exchange under the trading symbol PHARMX.

Posted: November 2007