<p>When Sofosbivur is used in combination with Ribavirin or Peginterferon alfa/ Ribavirin, the contraindications applicable to those agents are applicable to combination therapies. Sofosbuvir combination treatment with Ribavirin or Peginterferon alfa/Ribavirin is contraindicated in women who are pregnant or may become pregnant and men whose female partners are pregnant, because of the risks for birth defects and fetal death associated with Ribavirin.</p>