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 May, 2004

                                  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-      )
                                                 ------



                               [GRAPHIC OMITED]




Media  Release

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


                   4SC AG AND SERONO SIGN WORLDWIDE AGREEMENT
              TO DEVELOP AND COMMERCIALIZE ORALLY ACTIVE COMPOUNDS
                    FOR THE TREATMENT OF AUTOIMMUNE DISORDERS


            LEAD COMPOUND SC12267 COMPLETING PHASE I CLINICAL TRIALS


MARTINSRIED,  GERMANY  AND  GENEVA,  SWITZERLAND  -  MAY  4,  2004  -
4SC  AG  ("4SC"),  a  German-based  drug  discovery and development company, and
Serono  (virt-x:  SEO  and  NYSE:  SRA) announced today that they have signed an
agreement  under  which  4SC grants Serono exclusive worldwide rights to develop
and  commercialize  4SC's  program  of  dihydroorotate  dehydrogenase  (DHODH)
inhibitors. This program comprises a series of small molecules with potential as
orally  active  treatments in autoimmune disorders, such as rheumatoid arthritis
and  multiple  sclerosis.  The  agreement covers lead compound SC12267, which is
currently  completing  Phase  I  clinical  trials,  as  well  as further back-up
compounds  and  related  intellectual  property.

Under  the terms of the agreement, 4SC will receive an upfront payment, research
funding  and  potential  milestone  payments  related  to  development progress,
regulatory  submissions,  marketing  authorizations  and  commercial  sales
achievements.  If  products  are  successfully  developed,  registered  and
commercialized 4SC could receive up to USD 67 million from Serono. 4SC will also
receive  undisclosed  royalties  on  product  sales.

4SC  will  be  responsible  for  completion of the current multiple dose Phase I
study  on  SC12267,  while  Serono  will  be  solely  responsible  for  further
development,  regulatory approvals and commercialization, both of SC12267 and of
any  other  products  deriving  from  the  collaboration.

Dr  Ulrich Dauer, CEO of 4SC commented "Gaining Serono as a partner committed to
strongly expanding its presence in autoimmune disorders demonstrates the success
of  our  business  model  in  providing  attractive  drug  candidates  to  major
companies".  He  added "Revenues resulting from this partnership will contribute
to  the  sustainable growth of our small molecule drug discovery and development
pipeline".

"This  partnership with 4SC will further strengthen our development portfolio in
autoimmune  diseases,  building  on Serono's existing commitment to this area of
significant  medical  need"  said  Franck  Latrille,  Serono's  Head  of Product
Development.


                                                                             1/3

ABOUT SC12267

SC12267,  a  novel,  selective and orally available, small molecule inhibitor of
dihydroorotate dehydrogenase (DHODH), interferes with cell proliferation through
blocking  the  synthesis  pathway  of  pyrimidines.  Its  mode-of-action  is  of
therapeutic  relevance  for  the  treatment  of  autoimmune  disorders  such  as
rheumatoid  arthritis  and  multiple  sclerosis.  4SC was able to reach clinical
trials  with SC12267 in less than 3 years through application of its proprietary
virtual  screening  platform  and  state  of  the  art discovery capabilities in
medicinal  chemistry  and relevant disciplines. SC12267 has shown activity in in
vitro  and  in  vivo  models.  Ongoing  Phase  I  studies  indicate  favorable
pharmacokinetic  properties, suggesting a likely once daily dosing regime of the
well  tolerated  compound.


ABOUT  AUTOIMMUNE  DISORDERS

Autoimmune disorders are a severe medical problem. In general they are caused by
an over reactive immune response. Examples of this kind of disorder are multiple
sclerosis  (MS)  and  rheumatoid  arthritis (RA). MS is a disease of the central
nervous  system  (CNS),  which includes the brain, the spinal cord and the optic
nerves.  It  is  usually diagnosed between the ages of 20 and 40 and is twice as
common  in  women  as  in  men.  RA  is a very common disease affecting almost 6
million people around the world. It is characterized by inflammation of multiple
joints,  cartilage  loss  and bone erosion, which leads to joint destruction and
ultimately  reduced joint function. Fewer than 50% of patients diagnosed with RA
can continue to work or function normally on a day to day basis after ten years.


                                                                             2/3

                                       ###
Serono  forward-looking  statements
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  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.
                                       ###

ABOUT  SERONO
Serono  is  a  global  biotechnology  leader.  The Company has seven recombinant
products,  Rebif(R),  Gonal-F(R),  Luveris(R),  Ovidrel(R)/Ovitrelle(R),
Serostim(R), Saizen(R) and Zorbtive(TM) (Luveris(R) is not approved in the USA).
In  addition to being the world leader in reproductive health, Serono has strong
market  positions  in  neurology,  metabolism and growth. 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).

ABOUT  4SC
4SC  is  a  drug  discovery  and  development  company  that  uses  its
cheminformatics-based  technological  platform for the discovery and development
of  new  drug  candidates. By combining the disciplines of chemistry and biology
with the proprietary virtual High Throughput Screening technology, 4SCan(R), the
time  and  cost  of  advancing  a drug candidate to the development phase can be
significantly  reduced.  The  company's  therapeutic  focus  centers  on
hyperproliferative  and  infectious  diseases.  The  drug  candidate SC12267 for
treatment  of rheumatoid arthritis from 4SC's most advanced project is currently
being  tested in clinical Phase I. Additional research programs in disease areas
of cancer, inflammation, and bacterial infections are currently at the discovery
and  preclinical evaluation stage. 4SC, which was founded in 1997, today employs
60  people  and  is  based  in  Martinsried,  near  Munich,  Germany.

FOR MORE INFORMATION, PLEASE CONTACT:
SERONO IN GENEVA, SWITZERLAND:
MEDIA RELATIONS:               INVESTOR RELATIONS:
Tel: +41-22-739 36 00          Tel: +41-22-739 36 01
Fax: +41-22-739 30 85          Fax:
http://www.serono.com          Reuters: SEOZ.VX / SRA.N
---------------------          Bloomberg: SEO VX / SRA US

SERONO, INC., ROCKLAND, MA
MEDIA RELATIONS:               INVESTOR RELATIONS:
Tel.  +1 781 681 2340          Tel.  +1 781 681 2552
Fax:  +1 781 681 2935          Fax: +1 781 681 2912
http://www.seronousa.com
------------------------

4SC AG

Bettina von Klitzing
Tel:  +49-89-700 763 0
Fax:  +49-89-700 763 29
http://www.4sc.de


                                                                             3/3

                               [GRAPHIC OMITED]



Media Release

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


        SERONO LAUNCHES ZORBTIVE(TM), FIRST DRUG PRODUCT FOR TREATMENT OF
                              SHORT BOWEL SYNDROME

USE OF RECOMBINANT HUMAN GROWTH HORMONE REDUCES PATIENT DEPENDENCE ON PARENTERAL
                                    NUTRITION

GENEVA,  SWITZERLAND  AND  ROCKLAND,  MA, MAY 4, 2004 - SERONO (VIRT-X:  SEO AND
NYSE:  SRA)  -Serono,  Inc.,  the  US  affiliate  of Serono, announced today the
launch  of  Zorbtive(TM) [somatropin (rDNA origin) for injection] for use in the
treatment  of  patients  with  short  bowel  syndrome.

Short  bowel syndrome (SBS) is a rare and potentially life-threatening condition
in  which  the  ability  of the small intestine to absorb the nutrition a person
needs  from  food  is  impaired.  Short  bowel syndrome can occur after surgical
removal  of  part  of  the  intestine, due to trauma or because the intestine is
diseased.

"Many patients with SBS receive their basic nourishment by parenteral nutrition,
which  means they can spend eight to ten hours a day hooked up to an intravenous
feeding  line,"  says Kareem M. Abu-Elmagd, MD, PhD, FACS, Professor of Surgery,
Director of The Intestinal Rehabilitation and Transplant Center at the Thomas E.
Starzl  Transplantation  Institute  in  Pittsburgh, Pennsylvania.  "Reduction in
dependence  on  parenteral  nutrition  is  an  important  therapeutic  goal  for
patients.  Treatment  with  Zorbtive(TM)  may  help  to  achieve  this."

Results  from  a  pivotal  clinical  trial  showed  that  a four-week regimen of
Zorbtive(TM),  Serono's brand of recombinant human growth hormone for use in SBS
given  in  conjunction with specialized nutritional support, could significantly
reduce a person's dependence on intravenous feeding as measured by total volume,
total  calories  and  frequency of infusion.  Patients taking Zorbtive(TM) and a
supplemented specialized diet reduced the average number of days they had to use
intravenous  nutrition  by  4.2  days  per  week  versus  baseline,  which was a
significant  reduction  compared  to  the  average reduction seen in the control
group.  Additionally,  the  proportion  of  patients who were able to completely
discontinue  intravenous  feeding  was  greater  among  those  who  received
Zorbtive(TM).  Results  persisted  at  the  12-week  post-treatment  follow-up
assessment.

There  are  an  estimated  10,000-20,000  people  in  the  US  who are receiving
intravenous  parenteral  nutrition  for  SBS  who could potentially benefit from
Zorbtive(TM)  treatment.  Zorbtive(TM)  was  granted  a  seven-year  orphan drug
exclusivity  for  use  in  the treatment of patients with SBS by the US Food and
Drug  Administration.


                                                                             1/3

ADDITIONAL  PRODUCT  INFORMATION
Zorbtive(TM)  is  the  only  drug  product  approved  by  the  US  Food and Drug
Administration  specifically  for  the  treatment  of  SBS in patients receiving
specialized  nutritional support.  Optimal management of SBS may include dietary
adjustments, enteral feedings, parenteral nutrition, and fluid and micronutrient
supplements,  as needed. The recommended dose is 0.1 mg/kg daily up to a maximum
of 8 mg per day for a treatment period of four weeks.  Zorbtive(TM) is available
in  an  8.8  mg  vial  and  is  administered  by  subcutaneous  injection.

The  most  commonly  reported  adverse events during the clinical trial included
mild  injection-site  reactions, gastrointestinal disturbances, muscle and joint
pain,  and  edema/swelling.  Patients  with  a history of hyperglycemia or other
risk  factors  for  glucose  intolerance should be monitored closely.  Transient
increases  in  glucose  levels occur early in treatment and should be monitored.

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.

More  information  about  Zorbtive(TM)  can  be  found  in  the full prescribing
information  and  Treatment Guideline available online at www.zorbtive.com or by
                                                          ----------------
calling  SeroCare  at 1-800-714-2437.  Patients should be instructed to read the
Patient  Handbook  and  the  patient  package  insert  leaflet  accompanying the
product.


                                                                             2/3

ABOUT  SERONO
Serono,  Inc.,  located in Rockland, MA, is the US affiliate of Serono, a global
biotechnology  leader,  headquartered  in  Geneva, Switzerland. Serono has seven
recombinant  products,  Rebif(R)  (interferon  beta-1a), Gonal-F(R) (follitropin
alfa  for  injection),  Luveris(R)  (lutropin  alfa),  Ovidrel(R)/Ovitrelle(R)
(choriogonadotropin  alfa  injection), Serostim(R) [somatropin (rDNA origin) for
injection],  Saizen(R) [somatropin (rDNA origin) for injection] and Zorbtive(TM)
[somatropin  (rDNA  origin)  for  injection]. (Luveris(R) is not approved in the
USA.)(1)  In  addition  to being the world leader in reproductive health, Serono
has  strong  market  positions  in  neurology,  metabolism  and growth. Serono'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).


                                       ###

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, INC., ROCKLAND, MA
MEDIA RELATIONS:              INVESTOR RELATIONS:
Tel. +1 781 681 2481          Tel. +1 781 681 2552
Fax: +1 781 681 2935          Fax: +1 781 681 2912
http://www.seronousa.com
------------------------

SERONO IN GENEVA, SWITZERLAND:
MEDIA RELATIONS:             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




-----------------
(1) Package inserts for Serono's US marketed products are available at
www.seronousa.com or by calling 1-888-275-7376.


                                                                             3/3

                                   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)



May 4, 2004                         By:       /s/ Francois Naef
                                              -----------------------------
                                              Name:  Francois Naef
                                              Title: Secretary