<p>Losartan is 98.6-98.8% protein bound and the active metabolite (E-3174) is 99.7% protein bound in serum.<sup class="text-reference-group"><a class="reference-popover-link" data-content="Sica DA, Gehr TW, Ghosh S: Clinical pharmacokinetics of losartan. Clin Pharmacokinet. 2005;44(8):797-814. (PubMed ID 16029066)" href="#reference-A1033">1</a></sup></p>