It might seem as if Wall Street has given up on Gilead Sciences (GILD -0.06%). Its shares have fallen more than 25% from the highs set last year, when investors were excited about the prospects for remdesivir in treating COVID-19.

Don't expect things to change for the better now that Gilead has announced its first-quarter results, on Thursday following the market close. The biotech stock slid nearly 3% lower in after-hours trading. Here are the highlights from Gilead's Q1 update.

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Image source: Getty Images.

By the numbers

Gilead reported revenue in the first quarter of $6.4 billion, a year-over-year jump of 16%. Despite the improvement, though, this result fell short of the consensus Wall Street revenue estimate of $6.74 billion.

The company announced Q1 net income of $1.7 billion, or $1.37 per share, based on generally accepted accounting principles (GAAP). In the prior-year period, Gilead posted GAAP earnings of $1.5 billion, or $1.22 per share.

Gilead also delivered solid improvement on a non-GAAP basis. It recorded adjusted earnings of $2.08 per share, up from $1.68 per share in the prior-year period. However, this result narrowly missed the average analyst estimate of $2.09 per share.

Behind the numbers

Veklury (remdesivir) nearly single-handedly carried Gilead in the first quarter, with sales of $1.46 billion. Without the COVID-19 drug, the company's total product sales would have fallen 11% year over year.

Gilead also had a few other bright spots in Q1. Sales for HIV powerhouse Biktarvy rose 8% to $1.82 billion. Cell therapies Yescarta and Tecartus combined for sales of $191 million, up 36% from the prior-year period. Cancer drug Trodelvy generated $72 million in sales in its first full quarter on the market. Sales of drugs for hepatitis B and hepatitis D also jumped 18%, to $220 million.

However, the biotech had plenty of problem areas. Despite the continued strength of Biktarvy, Gilead's total HIV product sales slid 12% lower, to $3.7 billion. The loss of U.S. exclusivity for Truvada and Atripla weighed heavily on the company's HIV franchise. Year-over-year comparisons were also challenging for Descovy, because of stocking in the first quarter of 2020 related to the COVID-19 pandemic.

Gilead's hepatitis C virus (HCV) drugs continued to perform dismally as well. HCV product sales plunged 30% to $510 million, with the pandemic playing a key role in the decline. The company's older products, Letairis and Ranexa, also experienced further sales declines due to generic competition.

Looking ahead

Gilead Sciences CEO Daniel O'Day stated in the company's Q1 press release that "2021 is a pivotal year for Gilead, with key milestones across our virology and oncology portfolios." Probably the most pivotal aspect of the year, though, will be what happens with COVID-19.

The company maintained its full-year 2021 guidance issues in February. Gilead still expects product sales excluding Veklury to be between $21.7 billion and $22.1 billion, with Veklury sales between $2 billion and $3 billion. Non-GAAP earnings per share are projected to be between $6.75 and $7.45.

However, Gilead noted that sales of Veklury will "be subject to significant volatility and uncertainty." With the biotech relying so heavily on the COVID-19 drug for its growth, this could mean that its stock price will remain under pressure until Gilead has other positive catalysts.