Crown the new drug launch king: Gilead's Harvoni has knocked aside sister med Sovaldi

Move over, Sovaldi--there's a new launch king in town. And luckily for Gilead, it's another of its own.

Harvoni has officially unseated its hep C predecessor, putting up $2.11 billion in revenue in its first quarter on the U.S. market. While that's less than Sovaldi recorded in Q1 of last year--it posted $2.27 billion in sales--Harvoni's Oct. 10 approval meant it missed two weeks of Q4 sales time.

That would have been more than enough put Harvoni past Sovaldi, the Motley Fool figures. With its FDA green light at the tail end of December 2013, Sovaldi had the full first quarter of 2014 to rack up those numbers.

Script stats tell the same story. Three months post-approval, Sovaldi prescriptions were just a shade above 6,500 per week. Harvoni topped the 7,000-per-week mark in less than three months, the publication says.

And in Harvoni's 17th week after launch, it notched 8,396 total prescriptions--nearly 400 more than Sovaldi's 8,006 in Week 17, Leerink Partners analyst Howard Liang wrote in a recent note to clients.

It's no surprise Harvoni is besting Gilead's ($GILD) first next-gen hep C star. The therapy combines Sovaldi with the NS5A inhibitor ledipasvir, and it charted cure rates above 90% in clinical trials. In three Phase III studies on patients with the tough-to-treat genotype 1 variant of the virus, the cocktail managed cure rates as high as 99.1%.

But the way Liang sees it, both drugs will need to ramp up their performance if they want to meet analysts' sales targets for this year's first quarter. Based on total prescriptions recorded in the week ended February 6, he calculates a $1.8 billion top-line haul "assuming full capture by IMS and 46% gross to net," he wrote. If the numbers stay flat, revise that down to $1.7 billion. Both would fall short of analysts' $2.4 billion pre-consensus estimate from earlier this month, he notes.

Similarly, while Sovaldi's total scripts were up for the week, jumping 5.9%, new prescriptions were down. And extrapolating from total prescriptions--and flat script numbers for the rest of the quarter--Liang sees just $403 million in quarterly sales. That's well below the $914 million Wall Street expects.

If revenue seems low, thank the pricing war AbbVie ($ABBV) helped touch off with payers when it rolled out its Harvoni rival, Viekira Pak. In response to an exclusive deal the Illinois pharma struck with PBM Express Scripts ($ESRX), Gilead has been offering up its own discounts to ink similar arrangements with Express Scripts' competitors. The result? A $26 billion to $27 billion sales forecast for 2015, which was modest enough to make investors balk.

- read the Motley Fool story

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