On December 21, 2023 BioNTech SE (Nasdaq: BNTX, "BioNTech") and Duality Biologics (Suzhou) Co. Ltd. ("DualityBio") reported that the U.S. Food and Drug Administration ("FDA") granted Breakthrough Therapy designation for BNT323/DB-1303 for the treatment of advanced endometrial cancer in patients who progressed on or after treatment with immune checkpoint inhibitors (Press release, BioNTech, DEC 21, 2023, View Source [SID1234638746]). BNT323/DB-1303 is a next-generation antibody-drug conjugate ("ADC") candidate targeting the Human Epidermal Growth Factor Receptor 2 ("HER2"), a cell surface protein which is expressed in a range of tumor types. The designation is based on encouraging topline data from a Phase 1/2 study (NCT05150691) with BNT323/DB-1303 in patients with HER2-expressing advanced endometrial cancer.
Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:
Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing
Schedule Your 30 min Free Demo!
Endometrial or uterine cancer is the second most common gynecologic cancer globally, with over 400,000 cases occurring each year1,2 and both incidence and mortality are increasing3,4. While localized, early disease stages can be cured via surgery, the five-year survival rate for patients with advanced, metastatic or recurrent disease is only 18.4%5.
"The Breakthrough Therapy designation for BNT323/DB-1303 shows the potential of our ADC candidate to address current treatment challenges for patients with advanced HER2-expressing endometrial cancer who progressed under several lines of systemic therapy. For these patients the survival rates are still low and the medical need for new and more effective treatments remains high," said Prof. Özlem Türeci, M.D., Chief Medical Officer and Co-Founder at BioNTech. "With the designation and support by the FDA, we seek to expedite further development of BNT323/DB-1303."
"The FDA’s decision is an important milestone in the development of our novel differentiated ADC candidate directed at HER2. The HER2 protein overexpression and/or gene amplification is present in approximately 17% to 38%6 of patients with endometrial cancer and more than 50%7 of patients in late disease stage exhibit HER2 overexpression. We believe BNT323/DB-1303 has the potential to serve as a new therapeutic option for patients with HER2 expressing advanced endometrial carcinoma including both patients with high and low expression levels of HER2," said Vivian Gu, M.D., Chief Medical Officer at DualityBio. "We are committed to advancing BNT323/DB-1303 with the aim to improve outcomes for patients in late disease stages."
Breakthrough Therapy designation is an FDA program designed to expedite the development and regulatory review of investigational therapies that are designed to address serious or life-threatening conditions. To receive the designation, the candidate needs to demonstrate preliminary clinical evidence that indicates that it may offer substantial improvement over existing therapies on one or more clinically significant endpoints. With the Breakthrough Therapy designation, the development of BNT323/DB-1303 may benefit from more frequent engagement with the FDA, which will support the collection of appropriate data needed to accelerate development and may also allow for priority review if the relevant criteria are met.
Data presented from the ongoing Phase 1/2 study at ASCO (Free ASCO Whitepaper) 2023 and ESGO 2023 demonstrated encouraging anti-tumor activity in heavily pretreated patients with advanced endometrial cancer with an unconfirmed objective response rate of 58.8% and an unconfirmed disease control rate of 94.1%. BNT323/DB-1303 was well tolerated with a manageable safety profile across all evaluated patients with advanced/metastatic solid tumors.
The BNT323/DB-1303 program received FDA Fast Track designation for the treatment of endometrial cancer in January 2023.
About BNT323/DB-1303
BNT323/DB-1303 is a third-generation topoisomerase-1 inhibitor-based ADC targeting HER2 which was built from DualityBio’s proprietary Duality Immune Toxin Antibody Conjugates ("DITAC") platform. HER2 is a surface-expressed protein on solid tumors and has been linked to the aggressive growth and spread of cancer cells, making it a potential target for innovative cancer therapeutics. The candidate has exhibited antitumor activity in both HER2-positive and HER2-low tumor models as well as in several solid tumor indications, including patients with breast, gastric, endometrial, biliary tract cancers, and other advanced solid tumors. Preclinical data and preliminary clinical data for BNT323/DB-1303 indicate its potential to target HER2 on solid tumors irrespective of expression level with a manageable safety profile and a potentially expanded therapeutic window. BNT323/DB-1303 is currently being evaluated in an ongoing Phase 1/2 study (NCT05150691) in patients with advanced/metastatic solid tumors and in a pivotal Phase 3 study (NCT06018337) in patients with Hormone Receptor-positive ("HR+") and HER2-low metastatic breast cancer that have progressed on hormone and/or cyclin-dependent kinase 4/6 ("CDK4/6") therapy.