Roche and its Genentech business confirmed plans to file regulatory approval applications for the antibody drug conjugate trastuzumab emtansine (T-DM1) to both FDA and the European authorities later this year. The decision to submit for approval comes on the back of positive data from the first Phase III study evaluating the drug in the treatment of metastatic breast cancer (mBC).
Trastuzumab emtansine is an ADC that combines Roche’s Herceptin (trastuzumab) antibody and ImmunoGen’s cancer-killing agent DM1, which are coupled using the latter firm’s linker technology. The resulting ADC is in global development by Roche under a collaboration agreement between ImmunoGen and Genentech.
The newly reported open-label Emilia study evaluated trastuzumab emtansine in patients with Her2-positive mBC whose disease had progressed following prior treatment with Herceptin and a taxane chemotherapy. Treatment with the ADC as monotherapy was compared with therapy using lapatinib and Xeloda. Topline data from the study showed that patients receiving the ADC had significantly longer progression-free survival. One- and two-year overall survival data aren’t yet available.
Trastuzumab emtansine is Roche’s first ADC candidate, and is in development against Her2-positive cancers. Two additional comparative monotherapy/combination therapy Phase III trials are ongoing. The Marianne study is evaluating trastuzumab emtansine in patients with Her2-positive breast cancer who haven’t yet been treated for their metastatic disease. The Th3resa trial involves patients with Her2-positive metastatic breast cancer who have already received both Herceptin and lapatinib.
Roche says that, building on results from transtuzumab emtansine studies to date, it now has some 30 ADCs in its pipeline.