Serono Announces Final Settlement of Serostim(R) Investigation

18 October 2005

Serono (virt-x: SEO
and NYSE: SRA) announced today that its U.S. affiliates have agreed to settle
the government investigation led by the U.S. Attorney's office in
Massachusetts into commercial practices related to Serostim(R). This
investigation was part of an ongoing industry-wide investigation by the states
and the federal government of commercial practices. The comprehensive
settlements with federal and state agencies will conclude all liabilities to
the government in connection with the investigation.
In April 2005, the company announced that it had taken a $725 million
provision to cover the settlement and related costs. The provision, which was
recorded as an exceptional charge in the company's earnings report for the
first quarter of 2005, will be sufficient to cover the comprehensive
settlements and related costs. The comprehensive settlements also include a
Corporate Integrity Agreement, administered through the Office of the
Inspector General.
"This settlement concludes a four-year government investigation into
commercial practices related to Serostim, and we are pleased to put the matter
behind us," said Thomas G. Gunning, Vice President and General Counsel, Serono
U.S. "The activities described in the settlement were confined to one unit in
our U.S. operations and cover a brief period in our history. Serono takes
compliance issues very seriously and has a rigorous compliance program to
ensure that its employees meet the highest ethical standards. We now look
forward to continuing to focus and devote our energies on our core mission of
developing treatments to meet unmet medical needs."

About Serono
Serono is a global biotechnology leader. The Company has eight
biotechnology products, Rebif(R), Gonal-f(R), Luveris(R),
Ovidrel(R)/Ovitrelle(R), Serostim(R), Saizen(R), Zorbtive(TM) and Raptiva(R).
In addition to being the world leader in reproductive health, Serono has
strong market positions in neurology, metabolism and growth and has recently
entered the psoriasis area. The Company's research programs are focused on
growing these businesses and on establishing new therapeutic areas, including
oncology. Currently, there are approximately 30 ongoing development projects.
In 2004, Serono achieved worldwide revenues of US$2,458.1 million, and a
net income of US$494.2 million, making it the third largest biotech company in
the world. Its products are sold in over 90 countries. Bearer shares of
Serono S.A., the holding company, are traded on the virt-x (SEO) and its
American Depositary Shares are traded on the New York Stock Exchange (SRA).

Forward-looking statement
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 be materially different from those expected
or anticipated in the forward-looking statements. Forward-looking statements
are based on Serono's current expectations and assumptions, which may be
affected by a number of factors, including those discussed in this press
release and more fully described in Serono's Annual Report on Form 20-F filed
with the U.S. Securities and Exchange Commission on March 16, 2005. These
factors include any failure or delay in Serono's ability to develop new
products, any failure to receive anticipated regulatory approvals, any
problems in commercializing current products as a result of competition or
other factors, our ability to obtain reimbursement coverage for our products,
the outcome of government investigations and litigation and government
regulations limiting our ability to sell our products. Serono has no
responsibility to update the forward-looking statements contained in this
press release to reflect events or circumstances occurring after the date of
this press release.

For more information, please contact:
Media Relations, USA: Investor Relations, USA
Tel: +1 781 681 2340 Tel: +1 781 681 2552
Fax: +1 781 6812935 Fax: +1 781 681 2912
http://www.seronousa.com

Corporate Media Relations: Corporate Investor Relations:
Tel: +41 22 739 36 00 Tel: +41 22 739 36 01
Fax: +41 22 739 30 85 Fax: +41 22 739 30 22
http://www.serono.com Reuters: SEO.VX / SRA.N
Bloomberg: SEO VX / SRA US