Gilead Sciences' hepatitis C drugs, Sovaldi and Harvoni, will get exclusive coverage on several plans from CVS/Caremark, the pharmacy benefits manager said Monday, taking the opposite stance from competitor Express Scripts.

Gilead shares spiked on the news Monday, driving up the entire biotech sector. Last month, shares of Gilead swooned after Express Scripts said it would exclusively offer competitor AbbVie's newly approved hepatitis C therapy on its largest plan.