Roche's Perjeta helps breast cancer patients live a record-setting 15.7 months longer

These days, even expensive cancer treatments don't necessarily deliver show-stopping study results when it comes to actually extending patients' lives. Roche's ($RHHBY) Perjeta is now a major departure from that trend.

Thanks to previously released data, we knew that Perjeta helped patients with HER2-positive breast cancer live significantly longer. But how long is that? Almost 16 months, according to a study rolled out at the European Society for Medical Oncology meeting over the weekend.

Perjeta helped half of patients live at least 15.7 months longer than patients in the control group, the study data shows. In the world of metastatic, HER2-positive breast cancer, that's a whopping result.

"We've never seen anything like this before," lead author Sandra Swain of MedStar Washington Hospital Center told The New York Times. "It's really unprecedented to have this survival benefit."

Launched in 2012, Perjeta has already carved out a sizable niche, but the company says about half of eligible women in the U.S. still aren't being treated with the drug. That might be a cost-related problem, at least in part: Perjeta's U.S. list price is about $5,900 per month, and it's used in tandem with Herceptin, which costs $5,300 per month.

But with those impressive survival stats, any stubborn payers could have trouble saying no. Roche says it will be asking regulators around the world to add the data to Perjeta's official label, which could help clear the way for increased sales.

Perjeta has also proven itself in patients with earlier stages of HER2-positive breast cancer. The drug won FDA approval for use before surgery a year ago, a move that cancer experts and FDA officials called "historic" and a "quantum leap" at the time.

- read the release from Roche's Genentech unit
- get more from the Times (sub. req.)

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