Roche, ImmunoGen gain speedy review for T-DM1 breast cancer breakthrough

Roche has gained the inside track in the final lap of a long and expensive race to win an FDA approval for the armed antibody T-DM1, a new approach to treating HER2-positive breast cancer that marks a significant advance for patients. The pharma giant put out the word that the agency has granted the antibody-drug conjugate a priority review, with a decision due by February 26, a little less than four months away.

Roche ($RHHBY) and its partner ImmunoGen ($IMGN)--which stepped up with the ADC technology and stands to gain a small, single-digit royalty stream from a likely blockbuster--may not have to wait out the full timeline ahead of the PDUFA date. The FDA has made a number of early calls this year in favor of targeted cancer drugs that it has watched closely over the years. In this case the agency also sent back Roche to do a pivotal study, rather than consider mid-stage data. And the results in Phase III were solidly in T-DM1's favor.

In early October Roche revealed that the armed antibody delivered a 32% reduction in the risk of death among patients in the pivotal Phase III study when compared to the standard-of-care arm. The median overall survival rate for T-DM1 patients hit an impressive 30.9 months, while patients taking a combination of Tykerb and Xeloda achieved a 25.1-month OS rate.

"We're very pleased that the FDA has granted Priority Review to the trastuzumab emtansine BLA," noted ImmunoGen CEO Daniel Junius. "This decision underscores the urgent need to have new and more effective treatment options available for patients with this cancer." The European Medicines Agency also accepted Roche's marketing application for T-DM1 for review, moving closer to an approval in that key market as well.

Analysts like Cowen's Simos Simeonidis believe that TDM-1 could be a bigger earner than Herceptin. A number of analysts have projected peak sales at $5 billion-plus.

- here's the press release

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