With Novartis' Kisqali, Pfizer faces its first in-class threat for Ibrance

Novartis Kisqali will take on Pfizer's Ibrance in the CDK 4/6 inhibitor market.

Thanks to its lightning-quick trip down the regulatory pathway, Pfizer’s Ibrance has had more than two years as the market’s only CDK 4/6 inhibitor. But Tuesday, that came to an end.

Novartis has launched Kisqali just one day after snagging an FDA thumbs-up for the med, meaning Pfizer’s hormone receptor-positive, HER2-negative breast cancer med will get its first taste of in-class competition. And as the Swiss drugmaker was quick to note, its treatment comes at a lower price tag.

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Does that mean Pfizer has to worry, though? Not necessarily. The drugmaker has plans it thinks can keep the blockbuster expanding at a rapid clip.

For starters, Pfizer has a “very robust life-cycle program” in place for the med, as CEO Ian Read told investors on the pharma giant’s Q4 conference call in January. Translation: trials in a variety of other breast cancer settings and other cancers that could lead to new approvals. That R&D program includes trials in early, advanced and recurrent breast cancer, and studies outside the breast cancer arena—in areas like pancreatic and head and neck cancer—too.

RELATED: Novartis rolls out flex pricing scheme for newly approved Ibrance rival Kisqali

Pfizer has blueprinted some tactics for pumping up Ibrance sales in its already approved indications, too. After all, 20% of 12,000 or so eligible docs in the U.S. haven’t written an Ibrance prescription yet, and of those who have, about 30% have only done so for one or two patients.

“Our initial strategy was to establish Ibrance as the standard of care with early adopting physicians,” Albert Bourla, president of Pfizer’s Innovative Health division, explained on the call. But “moving forward, we believe the growth will come from late adopters, many of whom have already prescribed Ibrance, but in a limited number of patients.”

Luckily for Pfizer, its new Novartis rival also comes with some recommended safety monitoring that could help Ibrance retain a convenience edge. Regulators recommend patients receive ECG monitoring before starting up treatment with Kisqali and repeat it at day 14 of the first cycle and the beginning of the second cycle.

Kisqali, though, isn’t the only med coming for a piece of Pfizer’s $2.14 billion in 2016 Ibrance revenue. Eli Lilly is also making its way through the clinic with prospect abemaciclib, for which the Indianapolis drugmaker is expecting a key data readout in the first half of this year. Kisqali, for its part, is expected to bring in $1.6 billion in sales by 2022.