A $100 million ad blitz has whipped up patient demand for Harvoni, the $1,100-a-pill hepatitis C treatment, even as the drug’s price has drawn a barrage of lawsuits, state investigations, and sharp condemnation from members of Congress.

STAT analyzed data from media research firms iSpot.tv and Kantar Media for the most detailed look to date at the aggressive consumer marketing strategy for Harvoni, made by Gilead Sciences Inc. of Foster City, Calif.

At a time when some insurers have been reluctant to cover — and some physicians have been reluctant to prescribe — such an expensive drug, Gilead has pushed Harvoni in front of potential patients at every opportunity: as they read celebrity gossip, watch science fiction shows, follow the news, and more. As a result, doctors say patients are coming in asking for the drug by name, apparently not deterred by the cost or by the heavy political and legal fire aimed at Harvoni’s price tag.

Patients “have Harvoni on the mind because of these TV commercials,’’ said Mount Sinai Hospital hepatologist Dr. Douglas Dieterich.

Indeed, the Harvoni marketing push, which launched last spring, has been one of the year’s most expensive prescription drug ad campaigns.

Just a handful of prescription drugs were advertised more widely, and most of those treat conditions — such as erectile dysfunction and type 2 diabetes — that afflict far more patients in the United States than hepatitis C. About 3.5 million Americans have the viral infection, which usually lies dormant for years but can eventually cause liver failure and liver cancer.

More than 11,000 ads for Harvoni have aired on TV networks from ABC to Animal Planet to Syfy. The total value of the time slots is estimated at $60 million to upwards of $80 million, the data show.

And the TV ads were just the start: Last year Gilead bought more than $30 million of ad space to tout Harvoni in magazines including People, Popular Mechanics, and Better Homes and Gardens, as well as more than $5 million of ads online. (The iSpot and Kantar data reflect the list price of TV, magazine, and digital ad space, and don’t take into account any discounts Gilead may have negotiated.)

On top of all that, Gilead has run other ads that don’t mention its hepatitis C drugs by name — but do find a way to get them in front of patients. The unbranded magazine and TV spots tell patients they “haven’t been forgotten’’ and urge them to go to a website for more information about hepatitis C. Patients who click to learn about treatment options end up at the Harvoni website. The cost of these unbranded ads is not included in the $100 million estimate for the Harvoni campaign.

Gilead spokeswoman Cara Miller declined a request for an interview about the company’s advertising strategy for Harvoni.

Harvoni and an earlier version of the drug, sold as Sovaldi, have been in the headlines lately because of an intense backlash over their costs. Before discounts, a full course of Harvoni is priced at $94,500 and a course of Sovaldi costs $84,000.

In Massachusetts, the attorney general has threatened to sue Gilead over those prices, suggesting that they may constitute unfair trade practices. The New York State attorney general, meanwhile, is investigating insurers that have denied patients coverage for Harvoni, Reuters reported last week.

And a Senate committee in December excoriated Gilead for putting profits over patients when it set the prices of its two drugs.

“If Gilead’s approach is the future of how blockbuster drugs are launched in America, it’s going to cost billions and billions of dollars to treat just a fraction of patients in America,’’ Senator Ron Wyden, a Democrat from Oregon, said at the time.

Amid all this negative publicity, US sales of Harvoni slowed down in the fourth quarter of last year — but the drug remains a blockbuster. It’s generated $12 billion in US sales since its approval in late 2014. Sovaldi, which is still used for some patients, has generated $11 billion in US sales since being approved in late 2013.

Sales have been brisk partly because the drugs work. In the vast majority of patients, they can cure hepatitis C with few side effects in a matter of weeks, eliminating the potential need for grueling — and expensive — treatments like liver transplants later in life.

Harvoni’s strong sales numbers likely also reflect Gilead’s aggressive advertising, which has targeted patients who have been living with the condition for years.

Increased screening in recent years has helped create a sizable population of patients who know they have hepatitis C but who haven’t yet addressed it. Others may know they’re at risk because of past behavior, such as intravenous drug use, but haven’t yet been tested.

To spur those groups into action, Gilead has heavily pushed a TV spot called “I am Ready,’’ which features graying men and women declaring that they’re finally prepared to confront, and overcome, hepatitis C. As rain melts into sunshine, off-screen narrators declare, “I am ready to put hep C behind me’’ and “I am ready to be cured.’’

Like most drug advertisers, Gilead last year devoted the majority of its TV ad dollars for Harvoni to the big broadcast networks ABC, NBC, CBS, and Fox — which draw increasingly aging viewers, including baby boomers between the ages of about 50 to 70, who are five times more likely than other adults to have hepatitis C.

Harvoni ads also target more niche audiences. Consider the $600,000 of Harvoni ads last year in the AARP magazine. Or the $3 million Gilead spent advertising on Black Entertainment Television and in Ebony magazine — which makes sense given that African-American baby boomers are twice as likely as others in that age group to have hepatitis C.

Men are also disproportionately likely to have hepatitis C, which may explain Gilead’s investment last year in a collective $13 million of ads on ESPN and the Golf Channel and in Sports Illustrated and Men’s Journal.

Gilead is wooing patients directly at a time when both private insurers and Medicaid programs are balking at the high price of Harvoni. In some cases, they’re only agreeing to pay for treatment for the sickest patients, leaving those with relatively healthy livers unable to get treated. Other insurers will only pay for a competitor’s lower-priced drug.

Doctors, too, have proved a barrier; some are encouraging patients to hold out for cheaper therapies.

“A lot of physicians are taking a wait-and-see attitude,’’ said John Mack, who publishes Pharma Marketing News. As a result, he said, Gilead is going directly to patients, trying to “push them’’ into talking with their doctors and requesting the medication by name.

Dieterich, of Mount Sinai Hospital, said that physicians sometimes have to “do a little fast-talking’’ to reassure patients that other medications can work just as well as the brand-name drug they’ve seen so often on TV. Competing hepatitis C drugs Viekira Pak and Zepatier aren’t being advertised, so Gilead has the field to itself.

“We’re battling their successful direct-to-consumer advertising,’’ Dieterich said.

Gilead has said it’s expecting sales from Sovaldi and Harvoni to flatten this year, but the ads may well continue.

The company is already eyeing new markets: It got new approvals last month to market Harvoni for a new segment of patients with hepatitis C, those with advanced liver disease.

Rebecca Robbins can be reached at rebecca.robbins@statnews.com. Follow her on Twitter @RebeccaDRobbins. Follow Stat on Twitter: @statnews.