CytomX Therapeutics, Inc. (NASDAQ:CTMX) Q2 2020 Earnings Conference Call - Final Transcript
Aug 06, 2020 • 05:30 pm ET
Sean A. McCarthy
are advancing into Phase 2 studies in breast cancer. CX-072, a Probody therapeutic targeting PD-L1 that we are advancing in combination with CX-2009 in triple-negative breast cancer. And BMS-986249, an anti-CTLA-4 Probody therapeutic currently in a randomized Phase 2 study in melanoma, which is being run by our partner Bristol-Myers Squibb.
In parallel with building and advancing our broad clinical pipeline, we have formed many strong partnerships with leading biopharmaceutical companies, including BMS, Amgen, AbbVie and Astellas, all of whom are advancing novel product candidates, utilizing our technology. We have integrated research and development capabilities and our ambition is to ultimately commercialize our products, ourselves and with our partners as we build our long-term, sustainable, values based organization.
I'd like to spend some time laying out the high level strategy for each of our four clinical assets and how the data we presented at ASCO 2020 has pointed the way to our Phase 2 programs, as we evaluate the full potential of each product candidate in further detail.
Let's begin with the CX-2029, a Probody drug conjugate targeting CD71. CD71 is also known as the transferrin receptor, a protein that is highly expressed on many cancer types. But due to its involvement in iron metabolism has been traditionally thought of as undruggable. We know, in fact, that antibody drug conjugates targeting CD71 are not developable to use a lethal toxicity at low doses in animal models. However, given the high potential of CD71, as a novel anti-cancer target, we have investigated whether our Probody technology can allow us to achieve therapeutic levels of an anti-CD71 drug conjugate in cancer patients, potentially unlocking this first-in-class approach across a range of different cancer types.
Our Phase 1 results presented at ASCO 2020 show for the first time that by employing our technology CD71 can indeed be targeted successfully in patients with advanced cancers. Our dose escalation study achieved therapeutic levels of CX-2029 and objective confirmed single agent responses were observed in patients with squamous non-small cell lung cancer and with head and neck squamous cell cancer.
The principal dose limiting toxicity seen in this Phase 1 study was anemia, which was managed with red blood cell transfusions. These promising Phase 1 results for CX-2029 are particularly important, because targeting CD71 is likely the most rigorous test we have conducted to-date to assess our Probody technology and these results we believe underscore the broad potential of our platform.
These Phase 1 data also resulted in CytomX earning a $40 million milestone payment from AbbVie, our partner for this program, which we received in the second quarter. CytomX continues to lead clinical developments in this global co-development and commercialization alliance. We expect to initiate Phase 2 expansion cohorts of CX-2029 at the dose of 3 milligrams per kilogram every three weeks in head and neck squamous cell carcinoma, squamous non-small cell lung cancer, squamous esophageal carcinoma and DLBCL in the second half of 2020 with potential for the first data readouts in late 2021.