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* R&D under microscope at GSK and Roche on Nov. 3 and 5
* New CEO's strategy main focus at Sanofi on Nov. 6
By Ben Hirschler
LONDON, Nov 1 (Reuters) - Three of Europe's top drugmakers -GlaxoSmithKline, Roche and Sanofi -face health checks this week at high-profile presentationsdesigned to show they can overcome looming market threats.
The unusual confluence of investor days comes at a testingtime for the $1 trillion-a-year global drugs industry, asdeal-making sweeps a sector facing mounting competitivepressures.
Chief executives at the three companies face differentchallenges, but they all have a point to prove.
GSK's Andrew Witty and Sanofi's new boss Olivier Brandicourtboth need to demonstrate recovery potential, after recentdisappointments, while Roche's Severin Schwan must show he canwithstand future cut-price competition to his group's topbiotech drugs.
"Roche probably has the easiest job, since we know they havegood data with new multiple sclerosis (MS) and oncology drugs,whereas GSK and Sanofi have quite a lot to prove," BerenbergBank analyst Alistair Campbell said.
Roche's three most anticipated drugs - ocrelizumab for MS,atezolizumab for cancer and ACE-910 for haemophilia - aretogether expected to rake in annual sales of some $5 billion by2020, according to consensus forecasts from Thomson ReutersCortellis, which is well above rivals.
Roche is particularly bullish on ocrelizumab, after itsucceeded in the hard-to-treat progressive form of MS and set anew benchmark for treating relapsing disease.
Like its Swiss rival, GSK is also seeking to showcase itsresearch and development (R&D) prowess at its first R&D event inmore than a decade. But after past setbacks in clinical trials,investor expectations are relatively low.
Much of the focus is expected to be on GSK's experimentalshingles vaccine Shingrix, Nucala for severe asthma, sirukumabfor rheumatoid arthritis and a new long-acting HIV medicine.
Beyond that, investors are keen to get a glimpse deeper intoGSK's pipeline to see whether the company's R&D can deliver inthe medium to long term as it seeks to offset declining sales ofthe best-selling inhaled lung treatment Advair.
A key question is how many of the 40 or so experimentalmedicines it has said it will profile at the event will be readyto move into final Phase III trials in the next 12 months.
Sanofi's situation is different and Brandicourt, who tookover as CEO in April, will give a broad strategy update, whichis expected to touch on cost savings, potential new groupstructures and the scope for acquisitions, as well as the drugpipeline.
His task has become more urgent since Thursday, when Sanofishocked the market by warning that sales at its main diabetesdivision would keep falling until 2018.
Brandicourt has already said he views M&A as "a very usefultool" for Sanofi, prompting speculation he may see opportunitiesfollowing a recent healthcare sector market correction. Someanalysts see that correction as one contributor to current talksbetween Pfizer and Allergan.
GSK will hold its R&D in New York on Nov.3, while Roche'spharma day is in London on Nov.5 and Sanofi is hosting its "meetmanagement" seminar in Paris on Nov. 6.
(Editing by Jane Merriman)
