Today: Gilead Sciences demolishes earnings expectations thanks to powerful sales of breakthrough hepatitis C drug Sovaldi. Also: Juniper Networks, VMware and Intuitive Surgical announce quarterly earnings as Netflix rises.

The Lead: Sovaldi gives gigantic boost to Gilead Sciences' sales

Gilead Sciences' revenues nearly doubled in one year thanks to the introduction of a breakthrough hepatitis C drug that produced more than $2 billion in sales in its debut quarter, the Foster City biopharmaceutical giant reported Tuesday.

Silicon Valley's largest biotech company announced that it amassed profits of $2.22 billion, or $1.13 a share, on total sales of $5 billion in the first three months of the year. The company's first-quarter revenues jumped 97.6 percent from the same quarter a year ago, thanks mostly to Sovaldi: The hep C drug, which was cleared by the FDA in December, produced $2.27 billion in sales during those three months.

ISI Group analyst Mark Schoenbaum said on Gilead's earnings conference call that the drug produced the largest quarterly sales for a pharmaceutical drug that he had found, living up to the prediction of Robert W. Baird analyst Brian Skorney, who said that the drug will break annual records in 2014. Overall, Sovaldi sales were double the average analyst estimate of $1.13 billion compiled by Bloomberg News, and were higher than even optimistic reports from analysts who suggest Gilead stock, Schoenbaum said.

"This is well above the very likely stale sell-side consensus estimates," Schoenbaum wrote in a note. "More importantly, it's above even the high end of buy-side expectations that I've heard floated in the past few weeks."

Gilead has faced negativity for its pricing of the drug, which costs $1,000 a pill in the United States and was acquired in the company's $11 billion purchase of Pharmasset in 2011. A panel of California medical experts labeled Sovaldi a "low value" treatment due to its high cost, and one member of Congress has asked Gilead to explain the pricing.

"The value of a cure, I tend to think, is underestimated in terms of the overall advantage that the health care system receives from it," Chief Operating Officer John Milligan said in Tuesday's conference call, detailing the long-term cost of treating patients with hepatitis C against the short-term cost of Gilead's drug regimen.

Investors pushed Gilead shares higher than $75.50 in late trading after the company's stock closed with a 1.8 percent gain at $72.86 ahead of the report.

Four of Silicon Valley's largest 35 technology companies announced earnings Tuesday afternoon. In addition to Gilead, the 8th largest tech company in the Bay Area, Palo Alto software company VMware (18th), Sunnyvale networking company Juniper Networks (20th) and Sunnyvale medical-tech company Intuitive Surgical (35th) released their first quarter financial reports.

VMware reported net income of $199 million, or 46 cents a share, on sales of $1.36 billion, representing 14 percent growth in both metrics from the same quarter a year ago. The gains fit with VMware's performance in 2013, when the company boosted revenues 13.1 percent and profits by 35.9 percent, as the company's infrastructure offerings for cloud customers catch on. After initially rising in late trading following the report, VMware stock fell lower than $100 after closing with a 0.3 percent gain at $105.15.

Juniper reported profits of $110.6 million, or 22 cents a share, on revenues of $1.17 billion, a 10 percent revenues gain and 21.5 percent net income advance from the same quarter a year ago. New Juniper CEO Shaygan Kheradpir, who has announced a reorganization that will include a workforce reduction, called the performance "solid." Juniper stock dipped slightly after closing with a 1.9 percent gain at $25.89.

Intuitive Surgical announced earlier this month that its results would be disappointing, and Tuesday's report lived down to those expectations. The Sunnyvale medical robotics company, which recently received clearance for a new product, reported net income of $44.3 million, or $1.13 a share, on revenues of $464.7 million, a sales decline of 24 percent from the same quarter a year ago. Despite the advance warning, Intuitive Surgical shares still plunged after the report, falling near $391 after closing with a 2.7 percent advance at $422.33.

SV150 market report: Wall Street gains as Netflix, Tesla shoot higher

Stock indexes rose Tuesday thanks to a strong performance from Silicon Valley stocks, as Netflix jumped following its Monday earnings report and Tesla topped a strong day from Bay Area cleantech companies.

Netflix rose 7 percent to $372.90 Tuesday after announcing the previous afternoon that it would increase prices for new customers of its streaming service after surpassing $1 billion in quarterly revenues from the offering for the first time. Analysts were effusive in their praise of the Los Gatos video-on-demand company's report. "With international expansion firmly in place and profitability achieved ahead of expectations ... and a $1-$2 price hike later this quarter, Netflix has gotten a lot more compelling," Cantor Fitzgerald analyst Youssef Squali wrote in a note. Potential rivals aren't scared of Netflix, though: AT&T announced a joint initiative that will pour $500 million into developing a rival service, joining Yahoo and Microsoft in recent efforts at new streaming services.

Tesla nearly matched Netflix's performance, gaining 7 percent to $218.64 after the first Model S deliveries in mainland China were celebrated on the ground by CEO Elon Musk, who discussed the company's plans for expansion in the world's most populous nation. The other three companies in the SV150's cleantech sector also had a sunny day on Wall Street: Solar panel manufacturer SunPower rose 6.7 percent to $29.37, solar installer SolarCity gained 6.6 percent to $60.91, and Silver Spring Networks moved 2.4 percent higher to $15.98. Cloud software companies also moved higher as a group Tuesday, after Morgan Stanley analyst Jennifer Swanson Lowe released a report publicizing a buying opportunity in the sector after recent weakness. Workday gained 4.4 percent to $81.37, NetSuite jumped 2.2 percent to $84.10 and Salesforce moved 1.7 percent higher to $57.08.

Google gained 1.1 percent to $545.50 as the Mountain View tech giant announced that it will begin offering app-install advertisements, matching a similar announcement from Twitter that arrived last week. Google did suffer a loss, however, as one of its top YouTube executives will reportedly depart his day-to-day operations. Apple moved 0.1 percent higher to $531.70 ahead of its Wednesday earnings report; the Cupertino tech giant's legal adversary, Samsung, disclosed in court Tuesday that Google agreed to insulate the Korean company from some of Apple's patent-infringement claims. Facebook, which will join Apple in announcing earnings Wednesday, gained 2.9 percent to $63.03, despite investors' bets against the Menlo Park company's stock. Rival Twitter fell 0.2 percent to $46.02 after announcing the launch of native advertisements on its biggest acquisition to date, MoPub, and the rollout of its redesign to all Web users.

Up: Netflix, Tesla, SunPower, SolarCity, Workday, AMD, Pandora, Facebook, Yelp, Zynga, Juniper, Gilead, Salesforce, SanDisk, Applied Materials, Google, Intuit, eBay

Down: Symantec, Yahoo, Hewlett-Packard, Intel, LinkedIn, Twitter

The SV150 index of Silicon Valley's largest tech companies: Up 11.84, or 0.86 percent, to 1,392.05

The tech-heavy Nasdaq composite index: Up 39.91, or 0.97 percent, to 4,161.46

The blue chip Dow Jones industrial average: Up 65.12, or 0.4 percent, to 16,514.37

And the widely watched Standard & Poor's 500 index: Up 7.66, or 0.41 percent, to 1,879.55

Check in weekday afternoons for the 60-Second Business Break, a summary of news from Mercury News staff writers, The Associated Press, Bloomberg News and other wire services. Contact Jeremy C. Owens at 408-920-5876; follow him at Twitter.com/jowens510.