Gilead Sciences, Inc. (NASDAQ:GILD) reported its latest quarterly earnings results, which sent the company’s shares tumbling as earnings missed Wall Street’s guidance.

The U.S. biopharmaceutical company experienced a slight increase to its stock before reporting earnings as shares were up 0.5% during regular trading hours. However, the company’s stock declined as the company missed analysts’ projections with net income of $1.54 billion, or $1.17 per share.

In the year-ago quarter, Gilead Sciences brought in $2.7 billion in net income, or $2.05 per share. On an adjusted basis, the company earned $1.48 per share, which was well below the $1.67 per share that analysts were calling for, according to data compiled by FactSet.

The company’s revenue tallied up to $5.09 billion, also failing to meet its own year-ago total of sales at $6.51 billion. The Wall Street consensus estimate was calling for Gilead Sciences to bring in revenue of $5.4 billion, according to data compiled by FactSet.

The drugmaker’s antiviral product sales, including the sales of HIV, chronic hepatitis B (HBV) and chronic hepatitis C (HCV) products tallied up to $4.4 billion for the first quarter of 2018, below the $5.8 billion from the same period in fiscal 2017.

For the fiscal year 2018, Gilead Sciences reiterated its outlook as it is calling for revenue in the range of $20 billion to $21 billion. Analysts expect this figure to be higher at $21.27 billion in revenue.

GILD stock fell about 5.5% after hours Tuesday.