FDA reviewers back Roche's Perjeta in early breast cancer

Roche's ($RHHBY) new cancer drug Perjeta could be on its way to a much bigger market. The drug shrank breast tumors in early stages of the disease, the FDA said in review documents ahead of an advisory panel meeting later this week. If the committee votes in favor of early Perjeta use, then the drug may soon have access to thousands more patients with HER2-positive disease.

Roche's study looked at Perjeta in combination with Roche's Herceptin and chemotherapy, compared with Herceptin and chemo alone. Patients on Perjeta and Herceptin saw statistically significant improvements in tumor size compared with those in the Herceptin-only arm, the FDA reveiewers noted.

Cancer therapy before surgery--known as neoadjuvant treatment--aims to shrink tumors enough to avoid a mastectomy. Typically, women with HER2-positive breast cancer are given Herceptin plus chemo if they're treated in the neoadjuvant setting, Bloomberg notes. Roche is asking for approval to market Perjeta as an add-on to that combination, under the FDA's accelerated approval program.

The FDA's staff reviewers weren't without questions about Perjeta's effects in these patients. Agency staff suggested that the advisory panel consider requiring future clinical trials to determine the drug's effects on the heart. They also said trials should examine Perjeta's effects at various stages of breast cancer.

Approved last year, Perjeta is one of Roche's latest generation of HER2-positive breast cancer treatments. The drug has already built up impressive sales, with 108 million francs ($115.5 million) for the first half of 2013. It's designed to work with Herceptin--or with Roche's Herceptin-plus drug Kadcyla, approved earlier this year. That drug, a much-anticipated "armed antibody" treatment, is also in studies as a neoadjuvant therapy. Previously known as T-DM1, Kadcyla totted up 83 million francs in sales for the first half of this year, or about $89 million.

- read the Bloomberg piece

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