UNITED STATES ~~SECURITIES AND EXCHANGE COMMISSION~~

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 6-K

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

For the month of ~~July~~ September

Commission File Number 1-15096

Serono S.A.

(Translation of registrant’s name into English)

15 bis, Chemin des Mines
Case Postale 54
CH-1211 Geneva 20
Switzerland

(Address of principal executive office)

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 o

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): o

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): o

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 o No x

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

Media Release

FOR IMMEDIATE RELEASE

EUROPEAN COMMISSIONONE-YEAR APPROVES REVISIONDATA OFFROM THERAPEUTICPHASE INDICATIONIII FORTRIAL SHOW THAT NEW FORMULATION OF REBIF® OFFERS SUBSTANTIAL IMPROVEMENT

Throughout theIN EuropeanTOLERABILITY Union,AND multipleIMMUNOGENICITY sclerosis patients can now benefit from Rebif® as soon as their diagnosis of MS is confirmedPROFILES

~~Geneva,~~Data ~~Switzerland,~~Presented ~~July 10, 2006~~at ~~— Serono (virt-x:SEO and NYSE: SRA) announced today that the European Commission has approved an update of the Summary of Product Characteristics (SmPC) of Rebif®~~22nd ~~(interferon~~ECTRIMS ~~beta-1a),~~Congress in order to align it with current medical practice. Throughout the European Union, Rebif® can now be prescribed after the diagnosis of multiple sclerosis (MS) has been confirmed based on one attack and subsequent positive magnetic resonance imaging (MRI) scans.Madrid

~~The~~Madrid, ~~‘therapeutic~~Spain, ~~indication’~~September ~~section~~28, of2006 ~~the~~– ~~SmPC~~Serono ~~of Rebif® now~~(virt-x: ~~takes~~SEO ~~into~~and ~~account~~NYSE: ~~the~~SRA) ~~McDonald~~announced ~~criteria,~~today ~~which~~data ~~are~~from ~~the~~an ~~current~~ongoing ~~reference~~two-year ~~criteria~~(96 ~~for~~weeks) ~~the~~Phase ~~diagnosis~~IIIb oftrial ~~MS.~~show ~~The~~that ~~SmPC~~the ofnew formulation of Rebif® ~~was~~(interferon ~~previously~~beta-1a) ~~based~~44 onmcg ~~the~~subcutaneously ~~Poser criteria,~~(sc) ~~which~~three ~~were~~times inweekly ~~use~~(tiw) at for the ~~time~~treatment of ~~Rebif® approval~~relapsing informs ~~the~~of ~~European~~multiple ~~Union~~sclerosis ~~in 1998, and Rebif® was consequently indicated for~~ (MS) ~~patients~~offers ~~who~~substantial ~~had~~improvement ~~experienced~~in attolerability ~~least~~and ~~two~~reduction ~~attacks.~~in ~~Compared~~antibody ~~with~~formation ~~the~~observed ~~Poser~~at ~~criteria, the~~one ~~McDonald~~year ~~criteria~~(48 ~~utilize~~weeks), ~~MRI~~compared ~~evidence~~with ashistorical andata ~~alternative~~from topatients. aHistorical ~~second attack,~~data ~~and~~for ~~allow~~ the ~~same~~currently ~~patients~~available toformulation beof ~~diagnosed~~Rebif® is ~~with~~the ~~more sensitivity and~~EVIDENCE ~~specificity~~study. ~~Current~~These ~~understanding~~data ofare ~~the~~presented ~~disease~~today ~~supports~~at ~~that~~a itsatellite issymposium ~~critical to~~at ~~initiate treatment as soon as~~ the ~~diagnosis~~22nd Congress of MSthe European isCommittee ~~established~~for toTreatment ~~ensure the~~and ~~best~~Research ~~possible~~in ~~outcome~~Multiple ~~for~~Sclerosis ~~the~~(ECTRIMS) in ~~patients~~Madrid, Spain.

“WeThese results are ~~delighted~~promising ~~with~~news ~~the~~for ~~European~~patients ~~Commission~~with ~~decision~~multiple sclerosis,” said ~~Roberto~~Prof ~~Gradnik,~~Per ~~Senior~~Soelberg ~~Executive~~Sørensen, ~~Vice~~from ~~President~~the ~~Europe~~Danish ~~at Serono. “~~MS ~~has an initial stage when clinical manifestations are not~~ ~~pronounced~~Research ~~but~~Center, ~~irreversible~~Copenhagen ~~neurological~~University ~~damage~~Hospital, isRigshospitalet ~~taking~~and ~~place. This neurological~~an ~~damage~~investigator ~~determines the relative risk~~ of ~~progression of~~ the ~~disease~~trial. ~~People~~“If ~~with MS~~approved ~~living in Europe will be able to benefit from~~ the ~~proven~~new ~~efficacy~~formulation of Rebif® aspotentially ~~soon~~represents asan MSimprovement isin ~~diagnosed,~~the treatment ~~when~~of itpatients iswith ~~needed most”~~multiple sclerosis.”

~~Rebif® is~~The ~~proven~~incidence ~~effective~~of oninjection ~~the~~site ~~following~~reactions ~~three~~with ~~key~~the ~~measures~~new formulation of ~~treatment~~Rebif® at ~~effectiveness:~~48 ~~MRI~~weeks ~~lesion~~was ~~area~~nearly ~~and~~three-fold ~~activity,~~less ~~relapse~~than in ~~rates,~~the ~~and~~EVIDENCE ~~disability~~study ~~progression~~(29.6% ~~The~~versus ~~safety~~83.8%). ~~and~~Injection ~~efficacy~~site ofreactions ~~Rebif®~~ are ~~supported~~one byof the ~~eight-year~~reasons ~~follow-up~~why ~~data~~some ~~and~~patients discontinue MS treatment. Treatment enhancements 12resulting ~~years~~in a decrease of ~~patient~~injection ~~experience~~site ~~from~~reactions are usually associated with ~~around~~improved ~~the~~compliance ~~world~~and adherence to treatment.

The ~~European~~primary ~~Commission~~endpoint ~~decision~~of ~~means~~the ~~that~~study is the proportion of neutralizing antibody positive patients at the last ~~updated~~assessment. ~~SmPC~~At 48 weeks, the data showed that 13.9% of patients treated with the new formulation of Rebif® iswere ~~valid~~neutralizing ~~immediately~~antibody inpositive. ~~all~~In 25the EVIDENCE ~~member~~study ~~states~~ at 48 weeks, 24.4% of the ~~European~~patients ~~Union~~were positive. InPersistent neutralizing ~~most~~antibodies ~~other~~were ~~regions~~detected in 2.5% of the ~~world,~~patients ~~the~~treated ~~therapeutic~~with the ~~indication~~new formulation of Rebif® ~~already~~at ~~takes~~48 ~~into~~weeks. ~~account~~In the ~~McDonald~~EVIDENCE study at 48 ~~criteria~~weeks, the rate of persistent neutralizing antibodies observed was 14.3%.

1“The new formulation of Rebif® has been developed by an innovative approach, using state-of-the-art technologies, with a major focus on the molecule’s structural and functional integrity”, said Franck Latrille, Senior Executive Vice President Global Product Development at Serono. “Based on the improvements in tolerability and immunogenicity, the new formulation of Rebif® could lead to an improved benefit-to-risk profile”.

~~About Rebif®~~1

The new formulation of Rebif® ~~(interferon~~is ~~beta-1a)~~the islatest aof ~~disease-modifying~~many ~~drug~~product ~~used~~developments from Serono to ~~treat~~continually ~~relapsing~~enhance ~~forms~~the ofconvenience and ~~multiple~~tolerability ~~sclerosis~~of ~~and~~Rebif®. isOther ~~similar~~enhancements have included the Rebiject II auto-injector to facilitate injections; a 29 gauge-5 bevel needle pre-filled syringe, the ~~interferon~~thinnest ~~beta~~needle in ~~protein~~a ~~produced~~ready-to-use bypre-filled syringe for the ~~human~~treatment ~~body~~of MS; and a titration pack designed to make starting on Rebif® therapy easier and more convenient. The new formulation of Rebif® is currently under regulatory review by the ~~Interferon~~European ~~helps~~Medicines ~~modulate~~Agency, the ~~body’s~~US ~~immune~~Food ~~system,~~and ~~fight~~Drug ~~disease~~Administration and ~~reduce~~other ~~inflammation~~healthcare authorities.

~~Rebif®,~~The ~~which~~results ~~was~~presented ~~approved~~today inare ~~Europe in 1998 and in~~ the US48-week ~~in 2002, is registered in more than 80 countries~~results ~~worldwide.~~from Ina ~~the~~96-week, ~~United~~Phase ~~States~~IIIb, ~~Rebif® is~~multicenter, cosingle-~~marketed by Serono~~arm, ~~Inc.~~ ~~and~~open-label ~~Pfizer~~study ~~Inc.~~evaluating ~~Rebif® has~~the ~~been~~safety ~~proven~~and toimmunogenicity ~~delay the progression~~ of ~~disability,~~ ~~reduce~~ the ~~frequency~~new formulation of ~~relapses and reduce MRI lesion activity and area(1).~~ Rebif® ~~is available in a 22 mcg and~~ 44 mcg sc ~~ready-to-use~~tiw ~~pre-filled~~in ~~syringe~~260 ~~and~~patients awith ~~titration~~relapsing ~~pack,~~forms ~~and~~of ~~can~~MS. beThe ~~stored~~primary atobjective ~~room~~of the ~~temperature~~study ~~for~~was up to 30compare ~~days~~the ifantigenicity aof ~~refrigerator~~new isformulation ~~not~~Rebif ~~available~~to historical data.

~~Most~~About commonly reported side effects are injection site disorders, flu-like symptoms, elevation of liver enzymes and blood cell abnormalities. Patients, especially those with depression, seizure disorders, or liver problems, should discuss treatment with Rebif® ~~with their doctors.~~

~~About~~Rebif® (interferon ~~Serono~~beta-1a) ~~Neurology~~is a disease-modifying drug used to treat relapsing forms of multiple sclerosis and is similar to the interferon beta protein produced by the human body. Interferon helps modulate the body’s immune system, fight disease and reduce inflammation.

~~In addition to~~ Rebif®, ~~Serono~~which ~~also~~was ~~offers~~approved ain Europe ~~second~~in ~~therapy~~1998 ~~within~~and ~~its~~in the US ~~portfolio~~in of2002, ~~multiple~~is ~~sclerosis~~registered ~~(MS)~~in ~~therapies: Novantrone® (mitoxantrone~~more ~~for~~than ~~injection~~80 ~~concentrate) for~~countries ~~worsening forms of MS~~worldwide. ~~Full~~In ~~prescribing~~the ~~information~~United ~~for~~States, ~~these~~Rebif® is ~~products~~co-marketed ~~can be obtained~~ by ~~contacting~~ Serono, orInc. ~~visiting~~and ~~the~~Pfizer ~~Serono website~~Inc. ~~Additional~~ ~~therapy~~Rebif® has ~~options~~been ~~are~~proven ~~currently~~to ~~under~~delay ~~development~~the atprogression ~~Serono, including cladribine~~of ~~tablets~~disability, ~~currently~~reduce ~~in Phase III studies and potentially~~ the ~~first~~frequency ~~oral therapy for treatment~~ of ~~MS,~~relapses ~~as well as osteopontin, an MMP-12 inhibitor, a JNK inhibitor~~ and ~~interferon~~reduce ~~beta:Fc,~~MRI inlesion ~~early-stage~~activity ~~development for MS~~and area(1). ~~Serono also~~ Rebif® is ~~taking~~available ~~a leading role~~ in ~~developing~~a an22 ~~understanding~~mcg ofand ~~the~~44 ~~role of~~mcg ~~genetics~~ready-to-use inpre-filled ~~MS,~~syringe ~~with~~and a ~~whole~~titration ~~genome~~pack, ~~scan~~and ~~currently~~can ~~underway.~~be ~~To-date,~~stored 80at ~~genes~~room ~~associated~~temperature ~~with~~for MSup ~~have~~to ~~been~~30 ~~identified,~~days ~~based~~if on a ~~40%~~refrigerator ~~scan. The project~~ is ~~due~~ tonot ~~be completed in 2006 and will improve understanding of the causes of MS and the appropriate therapeutic targets for the disease~~available.

~~About~~Most ~~multiple~~commonly ~~sclerosis~~reported side effects are injection site disorders, flu-like symptoms, elevation of liver enzymes and blood cell abnormalities. Patients, especially those with depression, seizure disorders, or liver problems, should discuss treatment with Rebif® with their doctors.

~~Multiple~~About ~~sclerosis~~Serono (MS) is a chronic, inflammatory condition of the nervous system and is the most common, non-traumatic, neurological disease in young adults. MS may affect approximately two million people worldwide. While symptoms can vary, the most common symptoms of MS include blurred vision, numbness or tingling in the limbs and problems with strength and coordination. The relapsing forms of MS are the most common.Neurology

In addition to Rebif®, Serono also offers a second therapy within its US portfolio of multiple sclerosis (1MS) ~~The~~ ~~exact~~therapies: Novantrone® (mitoxantrone ~~relationship~~for injection concentrate) for ~~between~~worsening ~~MRI~~forms ~~findings~~of MS. Full prescribing information for these products can be obtained by contacting Serono or visiting the Serono website. Additional therapeutic options are currently under development at Serono, including oral cladribine, currently in Phase III studies and potentially the ~~clinical~~first ~~status~~oral therapy for treatment of ~~patients~~MS, as well as several products in early stage development including: osteopontin, an MMP-12 inhibitor, a JNK inhibitor and interferon beta:Fc. Serono also is ~~unknown~~taking a leading role in developing an understanding of the role of genetics in MS, with a whole genome scan currently underway. To-date, 80 genes associated with MS have been identified, based on a 40% scan. The project is due to be completed in 2006 and will improve understanding of the causes of MS and the appropriate therapeutic targets for the disease.

2About multiple sclerosis

~~Background~~Multiple ~~material~~sclerosis (MS) is a chronic, inflammatory condition of the nervous system and is the most common, non-traumatic, neurological disease in young adults. MS may affect approximately two million people worldwide. While symptoms can vary, the most common symptoms of MS include blurred vision, numbness or tingling in the limbs and problems with strength and coordination. The relapsing forms of MS are the most common.

~~For~~(1) ~~free~~The ~~B-roll,~~exact ~~video~~relationship ~~and~~between ~~other content for Serono~~MRI findings and ~~its products, please visit~~ the ~~Serono~~clinical ~~Media~~status ~~Center~~of ~~www.thenewsmarket.com/Serono. You~~patients ~~can download print-quality images and receive broadcast-standard video digitally or by tape from this site. Registration and video~~ is ~~free to the media~~unknown.

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~~Some of the statements in this press release are~~Background 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 February 28, 2006. 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.material

~~###~~For free B-roll, video and other content for Serono and its products, please visit the Serono Media Center www.thenewsmarket.com/Serono. You can download print-quality images and receive broadcast-standard video digitally or by tape from this site. Registration and video is free to the media.

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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 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 February 28, 2006. 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 any government investigations and litigation. Serono is providing this information as of the date of this press release, and 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.

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About Serono

Serono is a global biotechnology leader. The Company has eight biotechnology products, Rebif®, Gonal-f®, Luveris®, Ovidrel®/Ovitrelle®, Serostim®, Saizen®, Zorbtive™ and Raptiva®. 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 and autoimmune diseases. ~~Currently, there are more than 25 on-going development projects.~~

In 2005, Serono, whose products are sold in over 90 countries, achieved worldwide revenues of US$2,586.4 million. Reported net loss in 2005 was US$106.1 million, reflecting a charge of US$725 million taken relating to the settlement of the US Attorney’s Office investigation of Serostim. Excluding this charge as well as other non-recurring items, adjusted net income grew 28.4% to US$565.3 million in 2005. 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).

For more information, please contact:

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

Media Relations, USA:		Investor Relations, USA:
Tel:	+1 781 681 2340	Tel:	+1 781 681 2552
Fax:	+1 781 681 2935	Fax:	+1 781 681 2912
http://www.seronousa.com

SIGNATURE

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.,~~	SERONO S.A.,
		~~a Swiss corporation~~	a Swiss corporation
		~~(Registrant)~~	(Registrant)
Date July 10, 2006		By:	/s/ Stuart Grant
Date	September 28, 2006		By: /s/ Stuart Grant
		Name:	Stuart Grant
			Name: Stuart Grant
		Title:	Chief Financial Officer
			Title: Chief Financial Officer

Filing Compare · MERCK SERONO S.A.