Tests two investigational drugs together in advanced breast cancer
Tests BNT323 with BNT327 in adults with advanced breast cancer.
Plain-language title generated from the registry record
Registry title: A Clinical Study to Find the Optimal Dose of an Investigational Treatment Called BNT323 When Used in Combination With Another Investigational Treatment, BNT327, and to Test if That Combination Treatment is Safe and Beneficial for Patients With Advanced Breast Cancer
Key facts
- Where
- Chicoutimi, London, Toronto, and Vancouver, CanadaSee the 4 sites
- Phase
- Phase 1/2
Where in Canada
- CIUSSS du Saguenay-Lac-Saint-JeanChicoutimi, CanadaTaking people
- London Health Sciences Centre (LHSC) - Victoria HospitalLondon, CanadaTaking people
- Sunnybrook Health Sciences CentreToronto, CanadaTaking people
- BC Cancer - VancouverVancouver, CanadaTaking people
Questions to ask the study team
- How often do I need to come in, and for how long each time?
- Are travel costs paid?
- Can I keep my own doctor?
- What happens if I want to stop?
Trial details
- Who runs it
- BioNTech SE
- Trial code
- NCT06827236EU 2024-517979-20-00
- Record updated
- 10 November 2026
- Original description
This is a Phase I/II, multi-site, open-label, two-part study designed to evaluate the efficacy, safety, optimized dose and contribution of components of BNT323 (also known as trastuzumab pamirtecan and DB-1303) in combination with BNT327 (also known as pumitamig and PM8002) in participants with hormone receptor-positive (HR+) or hormone receptor-negative (HR-), Human epidermal growth factor receptor (HER)2-positive, HER2-low (immunohistochemistry [IHC] 1+ or IHC 2+/in situ hybridization -), HER2-ultralow (IHC 0, with membrane staining) or HER2-null breast cancer (BC), or triple-negative breast cancer (TNBC).Read full original descriptionShow less
A Phase I/II, Multi-site, Open-label, Two-part Trial to Evaluate the Efficacy, Safety, and Pharmacokinetics of BNT323 in Combination With BNT327 in Participants With Advanced Breast Cancer
This is a Phase I/II, multi-site, open-label, two-part study designed to evaluate the efficacy, safety, optimized dose and contribution of components of BNT323 (also known as trastuzumab pamirtecan and DB-1303) in combination with BNT327 (also known as pumitamig and PM8002) in participants with hormone receptor-positive (HR+) or hormone receptor-negative (HR-), Human epidermal growth factor receptor (HER)2-positive, HER2-low (immunohistochemistry [IHC] 1+ or IHC 2+/in situ hybridization -), HER2-ultralow (IHC 0, with membrane staining) or HER2-null breast cancer (BC), or triple-negative breast cancer (TNBC).
Inclusion: Have pathologically documented BC that:; Is locally advanced, unresectable or metastatic; Has a confirmed HER2 status as determined by the local laboratory as standard of care testing prior to study screening (Part 1, Part 2 Cohorts 2 and 4) or the central laboratory (Part 2, Cohorts 1 and 3) from the most recently collected pre-randomization tumor sample; Has a documented history of HER2 expression consistent with the subgroup definitions (i.e., HER2-low, HER2-ultralow, HER2-null, HER2-positive, or TNBC) as per current American Society of Clinical Oncology/College of American Pathologists guidelines; Have measurable disease defined by RECIST v1.1; Has left ventricular ejection fraction ≥55% by either echocardiography or multi-gated acquisition (scanning) within 28 days before randomization/enrollment.
Exclusion: Have history of small bowel obstruction requiring hospitalization within the past 3 months prior to the first dose of IMP; Have clinically uncontrolled pleural effusion, ascites or pericardial effusion requiring drainage, peritoneal shunt, or cell-free concentrated ascites reinfusion therapy within 2 weeks prior to randomization/enrollment; Had prior treatment with topoisomerase I inhibitors, including antibody-drug conjugates with topoisomerase I inhibitor payloads such as trastuzumab deruxtecan; Have received any of the following therapies or drugs prior to the initiation of the study:; Participants who have received prior treatment with BNT323; Participants who received prior treatment with a programmed death-ligand 1 (PD-L1) / vascular endothelial growth factor (VEGF) bispecific antibody. Note: Prior treatment with programmed death 1 (PD-1)/VEGF bispecific antibodies, PD-1/PD-L1 inhibitors or anti-VEGF therapies are permitted; Have received other systemic immunostimulatory agents or immunosuppressive therapies (such as interferon-α, interleukin-2, or methotrexate) within 4 weeks prior to the initiation of study treatment or are within five half-lives of the treatment drug (whichever is longer). Exception: excluding local, intranasal, intraocular, intra-articular or inhaled corticosteroids, short term use (≤7 days) of corticosteroids for prophylaxis (e.g., prevention of contrast agent allergy) or treatment of non-autoimmune conditions (e.g., delayed hypersensitivity reactions caused by exposure to allergens); Have received systemic corticosteroids (at a dosage greater than 10 mg/day of prednisone or an equivalent dose of other corticosteroids) within 3 weeks prior to the initiation of study treatment; NOTE: Other protocol defined Inclusion/Exclusion criteria apply; Have an uncontrolled intercurrent illness that would limit compliance with study requirement or substantially increase risk of incurring adverse events; Have a history of (non-infectious) interstitial lung disease (ILD)/pneumonitis that required steroids, have current ILD/pneumonitis, or where suspected ILD/pneumonitis cannot be ruled out by imaging at screening.