A Study of DB-1303 vs Investigator's Choice Chemotherapy in Metastatic Breast Cancer

Sponsor
DualityBio Inc. (Industry)
Overall Status
Not yet recruiting
CT.gov ID
NCT06018337
Collaborator
(none)
466
1
2
43
10.8

Study Details

Study Description

Brief Summary

The goal of this clinical trial is to assess the efficacy of DB-1303 compared with investigator's choice chemotherapy in terms of progression-free survival (PFS) by blinded independent central review (BICR) in the HR+, HER2-low (IHC 2+/ISH- and IHC 1+)population.

Condition or Disease Intervention/Treatment Phase
Phase 3

Detailed Description

The study is an open-label, multi-center, randomized study in HR+, HER2-low breast cancer subjects whose disease has progressed on at least 2 lines of prior ET or within 6 months of first line ET + CDK4/6 inhibitor in the metastatic setting. The primary purpose of the study is to determine the efficacy and safety of DB-1303 compared with investigator's choice single agent chemotherapy in the target population. Approximately 466 subjects with HER2 IHC 2+/ISH- and IHC 1+ (HER2-low] expression will be randomized 1:1 across approximately 180 centers globally to receive either DB-1303 or investigator's choice single agent chemotherapy (capecitabine, paclitaxel or nab-paclitaxel) until RECIST 1.1 defined disease progression (PD), unless there is unacceptable toxicity, withdrawal of consent, or another criterion for discontinuation is met.

Study Design

Study Type:
Interventional
Anticipated Enrollment :
466 participants
Allocation:
Randomized
Intervention Model:
Parallel Assignment
Masking:
None (Open Label)
Primary Purpose:
Treatment
Official Title:
A Phase 3, Randomized, Multi-center, Open-Label Study of DB-1303 Versus Investigator's Choice Chemotherapy in Human Epidermal Growth Factor Receptor 2 (HER2)-Low, Hormone Receptor Positive (HR+) Metastatic Breast Cancer Patients Whose Disease Has Progressed on Endocrine Therapy (ET) (DYNASTY-Breast02)
Anticipated Study Start Date :
Nov 1, 2023
Anticipated Primary Completion Date :
Aug 1, 2025
Anticipated Study Completion Date :
Jun 1, 2027

Arms and Interventions

Arm Intervention/Treatment
Experimental: DB-1303

Enrolled Subjects will be randomized to receive a 8 mg/kg IV dose of DB-1303 on Day 1 of each cycle Q3W

Drug: DB-1303
IV

Active Comparator: investigator's choice single agent chemotherapy

Enrolled Subjects will be randomized to receive investigator's choice single agent chemotherapy (capecitabine:1000 or 1250 mg/m2, Oral, Twice daily orally for 2 weeks followed by a 1-week rest period in 3-week cycles; paclitaxel:80 mg/m2, IV, Every week (QW) in 3-week cycles; or nab-paclitaxel: 100 mg/m2, IV, Every week (QW) for 3 weeks followed by a one-week rest period in 4-week cycles) until RECIST 1.1 defined disease progression (PD), unless there is unacceptable toxicity, withdrawal of consent, or another criterion for discontinuation is met.

Drug: Capecitabine
Oral

Drug: Paclitaxel
IV

Drug: Nab-paclitaxel
IV

Outcome Measures

Primary Outcome Measures

  1. To assess the efficacy of DB-1303 compared with chemotherapy in terms of progression-free survival (PFS) [From the date of randomization until objective (RECIST 1.1 defined) disease progression]

    Tumor evaluation scans will be performed at screening (as baseline) with follow ups every 6 weeks (Q6W ± 1 week)

Secondary Outcome Measures

  1. To assess the efficacy of DB-1303 compared with chemotherapy in terms of overall survival (OS) in the HR+, HER2-low populationchemotherapy in terms of overall survival (OS) [From the date of randomization until objective (RECIST 1.1 defined) disease progression]

    Tumor evaluation scans will be performed at screening (as baseline) with follow ups every 6 weeks (Q6W ± 1 week)

  2. To further assess the efficacy of DB-1303 in terms of PFS by Investigator assessment, objective response rate (ORR), duration of response (DoR), disease control rate (DCR), and time to response (TTR) by BICR and Investigator assessment [From the date of randomization until objective (RECIST 1.1 defined) disease progression]

    Tumor evaluation scans will be performed at screening (as baseline) with follow ups every 6 weeks (Q6W ± 1 week)

  3. To assess the safety and tolerability profile of DB-1303 compared with investigator's choice chemotherapy. [From the date of randomization until objective (RECIST 1.1 defined) disease progression]

    Tumor evaluation scans will be performed at screening (as baseline) with follow ups every 6 weeks (Q6W ± 1 week)

  4. To assess the pharmacokinetics (PK) of DB-1303 (DB-1303 antibody-drug conjugate [ADC] and free payload P1003). [From the date of randomization until objective (RECIST 1.1 defined) disease progression]

    Tumor evaluation scans will be performed at screening (as baseline) with follow ups every 6 weeks (Q6W ± 1 week)

  5. To assess symptoms, functioning and health-related quality of life (HRQoL) in subjects treated with DB-1303 compared with investigator's choice single agent chemotherapy [From the date of randomization until objective (RECIST 1.1 defined) disease progression]

    Tumor evaluation scans will be performed at screening (as baseline) with follow ups every 6 weeks (Q6W ± 1 week)

  6. To assess the impact of treatment and disease state on health utility using the EQ-5D-5L [From the date of randomization until objective (RECIST 1.1 defined) disease progression]

    Tumor evaluation scans will be performed at screening (as baseline) with follow ups every 6 weeks (Q6W ± 1 week)

Eligibility Criteria

Criteria

Ages Eligible for Study:
18 Years and Older
Sexes Eligible for Study:
All
Accepts Healthy Volunteers:
No
Inclusion Criteria:
  1. Male or female adults (defined as ≥ 18 years of age or acceptable age according to local regulations at the time of voluntarily signing of informed consent).

  2. Pathologically documented breast cancer that:

  1. Is advanced or metastatic 2) Has HER2-low expression (IHC 1+ or IHC 2+/ISH-) as determined by the central laboratory result.

  2. Was never previously reported as HER2-positive (IHC 3+ or ISH+) as per ASCO/CAP guidelines.

  3. Is documented as HR+ (either ER and/or PgR positive [ER or PgR ≥1%]) per ASCO/CAP guidelines (Allison et al 2020).

  1. Must have an adequate tumor tissue sample available for assessment of HER2 by central laboratory, preferably in formalin fixation and paraffin embedding (FFPE) blocks based on a mandatory FFPE tumor sample obtained at the time of metastatic disease or later;

  2. ECOG performance status of 0 or 1.

  3. Must have had either:

  4. Disease progression on endocrine therapy + CDK4/6 inhibitor within 6 months of starting first line treatment for metastatic disease and considered appropriate for chemotherapy as the next treatment by the investigator, OR

  5. Disease progression on at least 2 previous lines of ET with or without a targeted therapy (such as CDK4/6, mTOR or PI3-K inhibitors) administered for the treatment of metastatic disease.

  6. No prior chemotherapy for advanced or metastatic breast cancer. Subjects who have received chemotherapy in the neo-adjuvant or adjuvant setting are eligible, as long as they have had a disease-free interval (defined as completion of systemic chemotherapy to diagnosis of advanced or metastatic disease) of >12 months.

  7. Life expectancy ≥12 weeks at screening.

  8. Subjects must have at least one measurable lesion as defined per RECIST v1.1 or have non-measurable, bone-only disease that can be assessed by CT or MRI or X-Ray. Lytic or mixed lytic bone lesions that can be assessed by CT or MRI or X-Ray in the absence of measurable disease as defined above is acceptable; subjects with sclerotic/osteoblastic bone lesions only in the absence of measurable disease are not eligible.

  9. Female subjects of childbearing potential who are sexually active with a non-sterilized male partner must use at least one highly effective method of contraception from the time of screening and must agree to continue using such precautions for 7 months after the last dose of study treatment.

  10. Non-sterilized male subjects who are sexually active with a female partner of childbearing potential must use a condom with spermicide from screening and throughout the duration of the study treatment and the washout period

Exclusion Criteria:
  1. Ineligible for all options in the investigator's choice chemotherapy arm.

  2. Uncontrolled intercurrent illness, including but not limited to, ongoing or active infection, uncontrolled or significant cardiovascular disease, serious chronic gastrointestinal conditions associated with diarrhea, or psychiatric illness/social situations that would limit compliance with study requirement, substantially increase risk of incurring AEs or compromise the ability of the subject to give written informed consent.

  3. Clinically uncontrolled pleural effusion, ascites or pericardial effusion requiring drainage, peritoneal shunt or cell-free concentrated ascites reinfusion therapy within 2 weeks prior to the randomization.

  4. Uncontrolled or significant cardiovascular disease

  5. Has as a history of (non-infectious) ILD/pneumonitis that required steroids, has current ILD/pneumonitis, or where suspected ILD/pneumonitis cannot be ruled out by imaging at screening.

  6. Subjects with prior use of immunosuppressive medication within 14 days prior to first study dose, except for intranasal and inhaled corticosteroids or systemic corticosteroids at doses less than 10 mg/day of prednisone or equivalent.

  7. Has unresolved toxicities from previous anticancer therapy, defined as toxicities (other than alopecia) not yet resolved to Grade ≤ 1 or baseline.

  8. Previous treatment with anti-HER2 therapy.

  9. Prior treatment with antibody-drug conjugate that comprised an exatecan derivative that is a topoisomerase I inhibitor.

  10. Prior randomization or treatment in a previous DB-1303 study regardless of treatment assignment.20. Has substance abuse or any other medical conditions such as psychological conditions, that may, in the opinion of the Investigator, interfere with the subject's participation in the clinical study or evaluation of the clinical study results.

Contacts and Locations

Locations

Site City State Country Postal Code
1 Texas Oncology - Baylor Charles A. Sammons Cancer Center Dallas Texas United States 75246

Sponsors and Collaborators

  • DualityBio Inc.

Investigators

  • Study Director: Raymond Zhao, DualityBio Inc.

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.
Responsible Party:
DualityBio Inc.
ClinicalTrials.gov Identifier:
NCT06018337
Other Study ID Numbers:
  • DB-1303-O-3002
First Posted:
Aug 30, 2023
Last Update Posted:
Aug 30, 2023
Last Verified:
Aug 1, 2023
Individual Participant Data (IPD) Sharing Statement:
No
Plan to Share IPD:
No
Studies a U.S. FDA-regulated Drug Product:
Yes
Studies a U.S. FDA-regulated Device Product:
No
Keywords provided by DualityBio Inc.
Additional relevant MeSH terms:

Study Results

No Results Posted as of Aug 30, 2023