Data and Safety Monitoring Board Recommends Discontinuation of Canvaxin(TM) Phase 3 Clinical Trial for Patients with Stage III Melanoma

CancerVax Corporation (NASDAQ:CNVX) and Serono(Virt-X:SEO) (NYSE:SRA) announced today their decision to discontinuethe Phase 3 clinical trial of Canvaxin(TM) in patients with Stage IIImelanoma based upon the recommendation of the independent Data andSafety Monitoring Board (DSMB), which recently completed its planned,third, interim analysis of the data from this study. The DSMB foundthat the data are unlikely to provide significant evidence of anoverall survival benefit for patients with Stage III melanoma who weretreated with Canvaxin(TM) versus those who received placebo.

"This news is particularly disappointing because we understand thedevastating impact of this disease on patients with advanced-stagemelanoma, as well as their families and friends. We are extremelygrateful for the strong support we have received for this clinicaltrial from the clinicians, nurses, study coordinators and, especially,the patients who participated in this clinical trial," said David F.Hale, President and CEO of CancerVax Corporation. "We will discontinueall further development and manufacturing operations for Canvaxin(TM),but we currently plan to continue to further the development of theother product candidates in our product pipeline, which we believehold promise for the treatment of patients with cancer."

"The Phase 2 results were promising, and we were thus hopeful thatthis highly innovative product would be successful in a Phase 3clinical trial in patients with Stage III melanoma," said FranckLatrille, Senior Executive Vice President, Corporate Global ProductDevelopment of Serono. "We continue to have a strong pipeline withfive Phase 3 programs and significant newsflow expected in the nextyear. Serono remains committed to oncology with Humax-CD4,adecatumumab and TACI-Ig, with study results from all three programsexpected in 2006."

There were no significant safety issues identified with either thePhase 3 clinical trial of Canvaxin(TM) in patients with Stage IIImelanoma, or with the Phase 3 clinical trial of Canvaxin(TM) inpatients with Stage IV melanoma, which was discontinued earlier thisyear. The recommendations to close both of these clinical trials werenot made because of any potential safety concerns. Once the data fromthese clinical trials are fully analyzed, they will be presented atappropriate scientific meetings.

About the DSMB and Interim Analyses

The DSMB consists of independent experts in medical and surgicaloncology, statistics and medical ethics who are not participating inthe clinical trials, whose primary responsibility is to monitor, on aperiodic basis, the data emerging from a clinical trial and to providerecommendations to the sponsor on whether a study should be modifiedor discontinued.

About CancerVax Corporation (www.cancervax.com)

CancerVax Corporation is a biotechnology company focused on theresearch, development and commercialization of novel biologicalproducts for the treatment and control of cancer. CancerVax has beenevaluating Canvaxin(TM) in a Phase 3 clinical trial for the treatmentof patients with Stage III melanoma in collaboration with Serono.CancerVax also has a pipeline of product candidates and technologiesthat are being developed for the potential treatment of cancer. Theseinclude SAI-EGF, a product candidate that targets the epidermal growthfactor (EGF) receptor signaling pathway; and D93, CancerVax's leadanti-angiogenic humanized monoclonal antibody. CancerVax plans to filean Investigational New Drug (IND) application for clinical trials ofD93 in early 2006, and to initiate a clinical trial with SAI-EGF inpatients with advanced non-small-cell lung cancer in 2006.

About Serono

Serono is a global biotechnology leader. The Company has eightbiotechnology products, Rebif(R), Gonal-f(R), Luveris(R),Ovidrel(R)/Ovitrelle(R), Serostim(R), Saizen(R), Zorbtive(TM) andRaptiva(R). In addition to being the world leader in reproductivehealth, Serono has strong market positions in neurology, metabolismand growth and has recently entered the psoriasis area. The Company'sresearch programs are focused on growing these businesses and onestablishing new therapeutic areas, including oncology. Currently,there are approximately 30 ongoing development projects.

In 2004, Serono achieved worldwide revenues of US $2,458.1million, and a net income of US $494.2 million, making it the thirdlargest biotech company in the world. Its products are sold in over 90countries. Bearer shares of Serono S.A., the holding company, aretraded on the virt-x (SEO) and its American Depositary Shares aretraded on the New York Stock Exchange (SRA).

CANCERVAX CORPORATION

CONFERENCE CALL AND WEBCAST TUESDAY, OCT. 4, AT 9:00 AM EASTERNTIME

CancerVax management will host a conference call on Tuesday, Oct.4, at 9:00 a.m. Eastern Time, to discuss the DSMB recommendation todiscontinue the Canvaxin(TM) Phase 3 clinical trial for patients withStage III melanoma. A live audio webcast of management's presentationwill be available at http://ir.cancervax.com. Alternatively, callersmay participate in the conference call by dialing (866) 831-6270(domestic) or (617) 213-8858 (international). The passcode is70660579. A replay of the conference call can be accessed by dialing(888) 286-8010 (domestic) or (617) 801-6888 (international). Thepasscode for the replay is 42654318. The webcast will also be archivedon CancerVax's website.

Forward Looking Statements

CancerVax Corporation

CancerVax cautions you that statements included in this pressrelease that are not a description of historical facts areforward-looking statements. For example, statements about the timingof the initiation of clinical trials with any of CancerVax's productcandidates, and plans and objectives of management, are allforward-looking statements. The inclusion of forward-lookingstatements should not be regarded as a representation by CancerVaxthat any of its plans will be achieved. Actual results may differmaterially from those set forth in this release due to the risks anduncertainties inherent in CancerVax's business including, withoutlimitation: the progress, timing and outcome of its clinical trials;its ability to obtain additional financing to support its operations,which could adversely affect its ability to continue to operate as agoing concern; the risk that the collaboration agreement forCanvaxin(TM) may be terminated by Serono in certain instances; therisk that CancerVax may be required to pre-pay the debt incurred toexpand its manufacturing capacity prior to the termination of the loanbecause of a failure to comply with covenants included in the loanagreement; unexpected adverse side effects or inadequate therapeuticefficacy of its product candidates that could delay or prevent productdevelopment or commercialization, or that could result in recalls orproduct liability claims; competition from other pharmaceutical orbiotechnology companies; CancerVax's limited experience inmanufacturing and testing biological products, which may result indelayed development or commercialization of its product candidates, aswell as lost revenue; and other risks detailed in CancerVax'sSecurities and Exchange Commission filings, including CancerVax'sAnnual Report on Form 10-K for the fiscal year ended December 31,2004, and Quarterly Report for the fiscal quarter ended June 30, 2005.You are cautioned not to place undue reliance on these forward-lookingstatements, which speak only as of the date hereof. Allforward-looking statements are qualified in their entirety by thiscautionary statement and CancerVax undertakes no obligation to reviseor update this news release to reflect events or circumstances afterthe date hereof. This caution is made under the safe harbor provisionsof the Private Securities Litigation Reform Act of 1995.

Serono

Some of the statements in this press release are forward-looking.Such statements are inherently subject to known and unknown risks,uncertainties and other factors that may cause actual results,performance or achievements of Serono S.A. and affiliates to bematerially different from those expected or anticipated in theforward-looking statements. Forward-looking statements are based onSerono's current expectations and assumptions, which may be affectedby a number of factors, including those discussed in this pressrelease and more fully described in Serono's Annual Report on Form20-F filed with the U.S. Securities and Exchange Commission on March16, 2005. These factors include any failure or delay in Serono'sability to develop new products, any failure to receive anticipatedregulatory approvals, any problems in commercializing current productsas a result of competition or other factors, our ability to obtainreimbursement coverage for our products, the outcome of governmentinvestigations and litigation and government regulations limiting ourability to sell our products. Serono has no responsibility to updatethe forward-looking statements contained in this press release toreflect events or circumstances occurring after the date of this pressrelease.

CancerVax(R) is a registered trademark of CancerVax Corporation.

Canvaxin(TM) is a trademark of CancerVax Corporation.