In companies that are innovative and growing, this problem takes care of itself. A growing company needs more employees and managers, and most of those managers come from inside. An innovative company is constantly raided by headhunters looking for employees to steal, again opening positions for employees to be promoted into.
If the company is struggling, as are large parts of Sanofi, these rules don't apply and you may have to jump ship to get what you want. That can be scary, and difficult if you have spouse and children who can't easily relocate, but that is reality. You work for a subsidiary of a multinational company that has lost patent protection on its best selling drugs, and its pipeline is not producing new blockbusters. Unless you are an EU citizen and speak French fluently don't expect too much.