Just what Sanofi and Regeneron wanted: A Dupixent rollout so zippy, it's fueling bigger sales forecasts

Sanofi and Regeneron’s new atopic dermatitis drug Dupixent is off to the kind of start drugmakers aim for, judging by the number of doctors who’ve already prescribed it—and the number of scripts they’ve written.

Regeneron executives said last week that 1,800 physicians have picked up their prescription pads for Dupixent, and the company estimated 3,500 scripts had been written as of May 4. Sanofi had cited 1,200 docs and 2,500 scripts in the first month after approval—through April 21 or thereabouts, Leerink Partners analyst Geoffrey Porges wrote.

That rate of prescribing is quite a bit higher than other new launches, as the partners know quite well, given the slow rollout for their PCSK9 cholesterol med Praluent. It even beats one of Novartis’ most successful launches, the psoriasis med Cosentyx, judging by data from QuintilesIMS.

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“The early IMS script trend suggests that Dupixent is ramping at more than double the pace of the successful Otezla launch, and at 2.5x the rate of PCSK9s, and 4x the rate of recent psoriasis launches of Cosentyx and Taltz,” Porges said.

As analysts noted, those numbers don’t show how many prescriptions were actually filled, but, in another positive sign, the med hit the market with coverage from two pharmacy benefits managers that together account for 25% of the overall U.S. coverage universe, Credit Suisse analyst Vamil Divan says. The companies worked with payers up front on pricing, and set a list price at $37,000.

“The levels of [prescription] demand would suggest access is not a key hurdle to patients and there is a high level of awareness of the product by patients and doctors,” Divan wrote in a Friday note.

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How does this translate into sales? Porges quoted consensus estimates of $137 million for 2017, with sales ramping up to $70 million in the fourth quarter. But his firm has put up considerably higher figures. Based on a formula incorporating prescription growth, reimbursment levels—growing to 45% by year’s end from 25% in the first quarter—plus drop-out rates and payer discount estimates, Leerink is looking for $320 million from Dupixent this year, $206 million of that in the U.S.

Canaccord Genuity also expects better-than-consensus performance: U.S. sales of $148 million plus $67 million abroad, for a grand total of $215 million.

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Bernstein’s Ronny Gal pointed out in a Monday note that 25% of scripts appear to have been filled so far, but that’s likely higher, given the hurdles to be cleared before prescriptions are approved. “[T]his is an under-estimation as all payers require prior authorization and the process is often longer than couple of weeks,” Gal wrote.

Though the “$100 million-plus run rate” implied by these early launch numbers is “fantastic,” Gal said, for now, pent-up demand is likely fueling the immediate surge. So, excited pharma-watchers shouldn’t let the launch trajectory go to their heads. “[T]here is no evidence to suggest peak sales potential should change,” Gal said.

Of course, Bernstein’s peak estimates are at $4 billion, well into blockbuster territory. Sanofi and Regeneron could do quite a bit with that.