Can Pfizer's new breast cancer med really cruise to $4B and beyond?

An early FDA approval is a bonus for any drug. But for Pfizer's ($PFE) new breast cancer drug Ibrance (palbociclib), the earlier-than-expected green light has given it a billion-dollar-plus boost--on paper, anyway.

There's the extra time to market the drug before its patents start to expire down the road, thanks to a breakthrough therapy designation, priority review and a final approval two months ahead of schedule. There's the fact that Pfizer has even more of a head start on rivals from AstraZeneca ($AZN) and Novartis ($NVS).

And then there's perception. Last summer, some top analysts weren't so sure palbociclib would hit the market on its first go-round with the FDA. Sales estimates were in the $2 billion range, partly because of anticipated competition with Eli Lilly's candidate abemaciclib and Novartis' experimental LEE011. Some physicians were skeptical, too, without data on whether the drug would actually be able to extend patients' lives.

That last question remains unanswered for now. But the mood turned more and more positive as an FDA decision neared, what with particularly when the agency said it didn't need to hold an advisory committee meeting to consider the drug. Now, with Ibrance's accelerated-and-early approval in hand, the skepticism appears to have vanished. Analysts now are talking about up to $5 billion in sales by 2020. Some physicians say the solid FDA backing, plus impressive progression-free survival stats--20 months, versus about 10 for the current standard of care--are enough to persuade them to pick up Ibrance immediately. As Kantar Health's Arnold DuBell recently said, the drug had "phenomenal efficacy in terms of PFS benefit and as a result will be very well-received."

And at a list price of $9,850 per month--putting a 17-month treatment course at more than $160,000--Ibrance certainly has the sort of price that can fuel quick sales growth.

Now, Leerink Partners expects "brisk" uptake, with 2015 sales topping the $150 million previously expected, and 2020 sales at $4 billion. JP Morgan is looking for $4 billion by 2020, too. Evercore/ISI Group's Mark Schoenebaum predicts $4.2 billion, noting that CKD products from AstraZeneca and Novartis are now about 2 years behind Ibrance. And Jeffries analyst Jeffrey Holdford is even more optimistic, with a forecast of $5 billion by 2020--and about $420 million this year.

Can Pfizer deliver on that sort of optimism? The company isn't talking about its plans for sales staffing, consumer advertising or brand-building. But the company knows that, just as they tracked palbo through the clinic, people will be watching closely to see how Ibrance's early sales numbers stack up to those estimates. And when you look back over Pfizer's history, the company has a strong track record when it comes to launches, with a few major duds aside.

Pfizer oncology president Albert Bourla

But Pfizer's oncology president, Albert Bourla, agrees with the optimistic analysts. "We are very excited about this initial launch," Bourla said during a recent call with analysts, citing the fact that it's been more than a decade since a new first-line drug for advanced breast cancer won approval.

Plus, he pointed out, the early Ibrance PFS data isn't just statistically significant, but "clinically meaningful," with its 10-month advantage over the current standard treatment. "As a result," Bourla concluded, "we expect the uptake to be robust."

Meanwhile, the company is looking for overall survival data on Ibrance later this year, with many large studies in process in other types of breast cancer. Plus, trials are underway looking at the drug in lung and prostate cancer, plus melanoma. With a couple more indications under its belt, some say Ibrance could be a $10 billion opportunity.

- see the Pfizer call transcript

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