Begrundelserne for uenighederne var ifølge visse medlemsstater, at virkningen af Vantas ikke var blevet sammenlignet med andre godkendte og effektive behandlinger, og at der heller ikke var tilstrækkelig dokumentation for lægemidlets sikkerhed.
The reasons for disagreement was that, according to some Member States, the efficacy of Vantas was not demonstrated in comparison to other approved, effective treatments and that the safety of Vantas also was not adequately demonstrated.