Sixth-to-market Sanofi scores niche nod for PD-1 player—and blockbuster wannabe—Libtayo

Sanofi's Libtayo will follow PD-1/PD-L1 rivals from Merck, Bristol-Myers Squibb, Roche, AstraZeneca and a Pfizer-Merck KGaA team to market. (Sanofi)

Sanofi and Regeneron’s new immuno-oncology drug may be the sixth member of its class to win FDA approval, but it already has something not all its predecessors do: a market all to itself.

Friday, U.S. regulators green-lighted Libtayo, a PD-1 inhibitor, to treat metastatic cutaneous squamous cell carcinoma (CSCC) in patients who aren’t candidates for curative surgery or radiation. The disease is the second most common form of skin cancer, accounting for about 20% of all U.S. skin cancer cases, Sanofi said (PDF).

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And not only is Libtayo the first PD-1/PD-L1 drug to net an approval in that indication, it’s the first drug, period.

With that fact in mind, Leerink Partners analyst Geoffrey Porges expects “adoption to be relatively rapid, and to see significant pent-up demand among a substantial prevalent pool of previously diagnosed patients,” he wrote in a note to clients, predicting Libtayo—priced on par with rivals at $12,130 per month—would treat 5,000 patients by 2021.

It gets better for Sanofi and Regeneron, which will hit the market behind in-class nemeses Merck & Co., Bristol-Myers Squibb, Roche, AstraZeneca and a Pfizer-Merck KGaA team. The Sanofi-Regeneron partnership is “likely to have this indication to themselves for several years at least,” Porges said, adding that he expects to see Libtayo’s U.S. revenue grow from $15 million this year to $600 million in 2021. Global sales will tally $1.4 billion that same year, according to his forecasts.

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Of course, Sanofi isn’t planning to keep Libtayo in a niche. Instead, it wants to jump into the lung cancer fray as soon as possible to snag a piece of a very lucrative pie. The way the French drugmaker sees it, Libtayo can eventually edge out a couple of rivals despite their head starts.

“I think we have the opportunity to be third” behind current leader Keytruda from Merck and Opdivo from Bristol-Myers Squibb,” Jorge Insuasty, senior vice president and global head of development, said during a press briefing this summer.