Citi analyst Robyn Karnauskas downgraded Gilead Sciences (GILD) to Neutral saying the company's Hepatitis C virus guidance of $7.5B-$9B is considerably lower than consensus at $12B and her estimate of $10B.

The shares, around $69-$70, do not leave enough upside to justify a Buy recommendation, Karnauskas tells investors in a post-earnings research note. She believes the new guidance could create a new floor in the stock and cut her price target for Gilead to $76 from $87. The shares are down $4.30, or 6%, to $68.83 in pre-market trading.