T-DM1, known as an “empowered antibody,” combines Genentech’s existing antibody drug trastuzumab (Herceptin) with ImmunoGen’s cancer-killing toxin DM1, for an added punch. The FDA stated that the souped-up drug did not meet the requirements for accelerated approval because all other treatments choices had not been exhausted for the patients with metastatic breast cancer who participated in the clinical trials of the drug.
Genentech submitted its application for accelerated approval for T-DM1 in July, based on clinical trial data showing that the drug had helped partially or completely shrink tumors in roughly one out of every three patients, in a group of volunteers who had already received an average of seven different drugs for their cancer. The data was presented in December at the San Antonio Breast Cancer Symposium.
ImmunoGen stock had fallen more than 35 percent as of 12:57pm today, to $5.43 per share. ImmunoGen also stated that the financial guidance it previously announced for fiscal year 2011 was no longer applicable due to the FDA “refuse to file” letter.
Following today’s FDA decision, Genentech indicated that it will continue its ongoing Phase III trial of T-DM1, as planned, and expects to submit a new application for the treatment in mid-2012, using a different data set than it had submitted for the accelerated approval application this summer.
“We firmly believe in the potential of T-DM1 as a novel HER2-targeted option and remain fully committed to its ongoing development,” said Hal Barron, Genentech executive vice president of product development and chief medical officer, in a company announcement of the news.
On its own, trastuzumab, which nabbed FDA approval as a breast cancer treatment in 1998, generates more than $5 billion in annual sales worldwide.
well, i think that is a appropriate decision from FDA to protect medical patients.