Vantaggi
I was at Sanofi for almost 5 years, and in that time I was able to transition through three different roles. I loved that my boss was so supportive of my development, helping me secure internal preceptorships and external certifications. If you're vocal about your passions and where you want to grow, Sanofi will probably support your learning, and they're very big on hiring and promoting from within.
Svantaggi
Despite the emphasis on people development and internal hiring, promotions and role changes are often more dependent on politics than qualifications. There is a disappointing lack of transparency around the posting and recruiting of internal positions. If you don't have a certain level of seniority or haven't brown-nosed with the right people, you can forget about being tapped for openings, regardless of credentials.