SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                    ________

                                    FORM 6-K

                        REPORT OF FOREIGN PRIVATE ISSUER
                      PURSUANT TO RULE 13a-16 OR 15d-16 OF
                       THE SECURITIES EXCHANGE ACT OF 1934

                         For the month of January, 2005

                                   Serono S.A.
                    -----------------------------------------
                               (Registrant's Name)

                            15 bis, Chemin des Mines
                                 Case Postale 54
                                CH-1211 Geneva 20
                                   Switzerland
                      ------------------------------------
                    (Address of Principal Executive Offices)

                                     1-15096
                    -----------------------------------------
                              (Commission File No.)

     (Indicate by check mark whether the registrant files or will file annual
reports under cover of Form 20-F or Form 40-F.)

     Form 20-F  X   Form 40-F
               ---            ---

     (Indicate by check mark if the registrant is submitting the Form 6-K in
paper as permitted by Regulation S-T Rule 101 (b)(1).)  ______

     (Indicate by check mark if the registrant is submitting the Form 6-K in
paper as permitted by Regulation S-T Rule 101 (b)(7).)   ______

     (Indicate by check mark whether the registrant by furnishing the
information contained in this form is also thereby furnishing the information to
the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of
1934.)

     Yes        No  X
         ---       ---

     (If "Yes" is marked, indicate below the file number assigned to the
registrant in connection with Rule 12g3-2(b): 82-______)



                                                                          SERONO


MEDIA RELEASE


FOR IMMEDIATE RELEASE
---------------------



      SERONO ANNOUNCES COMPLETION OF PATIENT ENROLLMENT IN PHASE III TRIAL OF
  SEROSTIM(R) (SOMATROPIN [RDNA ORIGIN] FOR INJECTION) IN HIV-ASSOCIATED ADIPOSE
                         REDISTRIBUTION SYNDROME (HARS)



GENEVA,  SWITZERLAND  AND  ROCKLAND,  MA, JANUARY 24, 2005 - Serono Inc., the US
affiliate  of  global  biotechnology  leader Serono (virt-x: SEO and NYSE: SRA),
announced  today  that  it  has completed enrollment in its second multi-center,
phase  III  trial of Serostim(R) (somatropin [rDNA origin] for injection) in the
treatment of HIV-Associated Adipose Redistribution Syndrome (HARS).

The  primary  goal of this randomized, double-blind, placebo-controlled trial is
to assess whether Serostim(R) induction therapy significantly reduces the marked
abnormal  accumulation  of visceral adipose tissue (intra-abdominal fat) and fat
maldistribution  which  characterize  HARS,  and  whether  low-dose  maintenance
therapy  prevents  the abnormalities from returning during a continued course of
therapy.

"We  are  pleased  to  have reached this major milestone for this very important
study,"  said  James  Sapirstein,  Executive  Vice  President  of  Metabolic
Endocrinology  at  Serono,  Inc.  "An  unmet need clearly exists in this patient
population.  Serono is committed to ensuring rapid completion of the trial and a
US  registration  submission  for  Serostim  as  a  treatment  for  this  orphan
indication."

"More  than  300  patients  were  enrolled  in the study in only six months. The
dedication  of  the  clinical  investigators,  all  study site personnel and our
in-house study team coupled with the need and enthusiasm for this project in the
HIV  community led to speedy enrollment of this study," said Paul Lammers, Chief
Medical  Officer at Serono, Inc. "The results of this pivotal Phase III clinical
trial  are  eagerly  awaited."


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ABOUT  HARS

HIV-associated  adipose  redistribution  syndrome  or  HARS  is  a subset of HIV
lipodystrophy.  HIV-associated  lipodystrophy  is  characterized by a variety of
metabolic  disturbances  and  body  shape  abnormalities  that  may  present
individually  or  in  combination.  Patients  with  HARS  experience  abnormal,
pathological  accumulation  of  adipose  tissue,  which  may  be present with or
without  fat depletion and/or metabolic abnormalities. In general, HARS patients
accumulate  excess  visceral  adipose tissue in the abdomen or may develop a fat
pad  on  the  upper  back  commonly  known  as  a  "buffalo  hump."



ABOUT  SEROSTIM(R)

Serostim(R)  [somatropin  (rDNAorigin) for injection] is the only growth hormone
approved by the US Food and Drug Administration for the treatment of HIV wasting
or cachexia. The recommended dose is 0.1 mg/kg daily (6 mg/day for patients > 55
kg).  Serostim(R)  0.1  mg/kg every other day should be considered as a starting
dose in patients thought to be at risk of certain adverse effects, e.g., glucose
intolerance.

Use  of  growth hormone is contraindicated in treatment of patients in intensive
care  units  due  to  complications  following  open-heart  surgery or abdominal
surgery,  multiple accidental trauma or acute respiratory failure; patients with
active  neoplasia;  and  patients with known hypersensitivity to growth hormone.
Serostim(R)  must  be  used  in  conjunction  with  antiretroviral therapy. Full
prescribing information for Serostim(R), including important safety information,
is  available  at  www.serostim.com.



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.  Currently,  there  are  approximately 30
ongoing  development  projects.

In  2003,  Serono  achieved  worldwide revenues of US$2,018.6 million, and a net
income  of  US$390.0 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).


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                                       ###


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 25, 2004.  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,  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:

SERONO, GENEVA, SWITZERLAND:

MEDIA RELATIONS:                       INVESTOR RELATIONS:
Tel:  +41-22-739 36 00                 Tel:  +41-22-739 36 01
Fax:  +41-22-739 3085                  Fax:  +41-22-739 30 22
http://www.serono.com                  Reuters:  SEO.VX / SRA.N
---------------------                  Bloomberg:  SEO VX / SRA US


SERONO, INC., ROCKLAND, MA

MEDIA RELATIONS:                       INVESTOR RELATIONS:
Stacie  Madden                         Tel:  +1 781 681 2552
Tel:  +1 781 681 2496                  Fax:  +1 781 681 2912
stacie.madden@serono.com
------------------------


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                                   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,  thereunto  duly  authorized.



                                        SERONO S.A.
                                        a Swiss corporation
                                        (Registrant)



January 24, 2005                        By:    /s/ Stuart Grant
                                               ---------------------------
                                        Name:  Stuart Grant
                                        Title: Chief Financial Officer