Sept 10 (Reuters) - Trial data on Swiss drugmaker Roche's breast cancer treatment Perjeta supported a faster approval of the drug for use in early stages of the disease, reviewers for the U.S. Food and Drug Administration said on Tuesday.
Roche is seeking approval for Perjeta as a neoadjuvant, or initial, treatment for early stage breast cancer patients whose cancer cells contain increased amounts of the HER2 protein.
A neoadjuvant treatment is given in the beginning to shrink a tumor before the main treatment. Perjeta, also known as pertuzumab, is currently approved as a first-line treatment for metastatic breast cancer.
If approved, Perjeta, to be used in combination with Roche's older breast cancer drug Herceptin and chemotherapy drug docetaxel, would be the first neoadjuvant breast cancer treatment approved by the FDA.
The agency is trying to set up a new, faster approval process for early-stage breast cancer drugs, including a proposed new clinical goal known as pathologic complete response (pCR), to support approval. Pathologic complete response is defined as absence of invasive cancer in the breast.
"FDA analysis of the Neosphere study showed statistically significant improvements in pCR rates by both the study and FDA-preferred definitions," FDA staff said in the briefing documents. ()
If considered in the neoadjuvant setting under the pCR pathway, an approval could come four years earlier than if the company were forced to wait for data from an ongoing trial expected in 2016, said Dietmar Berger, vice president of clinical development at Roche's Genentech unit.
About 220,000 people are diagnosed with early breast cancer in the United States each year. Of these, the company estimates that about 15,000 currently receive neoadjuvant treatment.
However, the reviewers added that an analysis found that while pCR has clear prognostic value for individual patients, an association between pCR and long-term outcome could not be confirmed at a trial level.
"Since there is uncertainty regarding the ultimate long-term efficacy and safety of drugs approved under this pathway, long-term follow-up with confirmation of clinical benefit will be needed," the reviewers said.
Since there are no approved neoadjuvant breast cancer treatments, there is technically no standard of care. However, the majority of people who currently receive neoadjuvant treatment for HER2-positive early breast cancer receive Herceptin and chemotherapy.
A panel of independent advisors to the FDA will review Perjeta's risks and benefits on Thursday, Sept. 12. The FDA, which takes the panel's recommendations into account, is expected to decide on the drug's approval by Oct. 31.