Et farmakodynamisk interaktionsstudie med raske frivillige viste, at administration af loperamid og APTIVUS givet sammen med lavdosis ritonavir ikke forårsager klinisk relevant ændring i det respiratoriske respons på kuldioxid.
A pharmacodynamic interaction study in healthy volunteers demonstrated that administration of loperamide and APTIVUS, co-administered with low dose ritonavir does not cause any clinically relevant change in the respiratory response to carbon dioxide.