Yes, it appears that Sanofi-Syntholabo messed up the early pricing of fondaparinux and I read somewhere this may have even helped Plavix' uptake as physicians transitioned to an oral alternative rather than a new innovative (but costly) injectable alternative.
It certainly seems true that post GSKs acquisition they have also failed to market it adequately - particularly given the VERY strong clinical data showing superiority over Lovenox and the ever increasing number of approved indications.
It seems GSK has a habit of under promoting solid drugs they have. They did the same thing with Relenza and missed out on huge upside from the first two years of the H5N1 scare and the associated government stockpiling because they never built out manufacturing capacity. They are only now starting to capture the value of Relenza.