A Study of DB-1303 in Advanced/Metastatic Solid Tumors
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ClinicalTrials.gov Identifier: NCT05150691 |
Recruitment Status :
Recruiting
First Posted : December 9, 2021
Last Update Posted : April 26, 2023
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
HER2-positive Advanced Solid Tumor | Biological: DB-1303 | Phase 1 Phase 2 |
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 363 participants |
Allocation: | Non-Randomized |
Intervention Model: | Single Group Assignment |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | A Phase 1/2a, Multicenter, Open-Label, Non-Randomized First in Human Study to Assess the Safety, Tolerability, Pharmacokinetics, and Preliminary Antitumor Activity of DB-1303 in Patients With Advanced/Metastatic Solid Tumors |
Actual Study Start Date : | January 31, 2022 |
Estimated Primary Completion Date : | June 2025 |
Estimated Study Completion Date : | October 2025 |

Arm | Intervention/treatment |
---|---|
Experimental: DB-1303 Dose Level 1
Enrolled Subjects will receive a single-dose of DB-1303 at Dose Level 1 on Day 1 of each cycle Q3W
|
Biological: DB-1303
Administered IV |
Experimental: DB-1303 Dose Level 2
Enrolled Subjects will receive a single-dose of DB-1303 at Dose Level 2 on Day 1 of each cycle Q3W
|
Biological: DB-1303
Administered IV |
Experimental: DB-1303 Dose Level 3
Enrolled Subjects will receive a single-dose of DB-1303 at Dose Level 3 on Day 1 of each cycle Q3W
|
Biological: DB-1303
Administered IV |
Experimental: DB-1303 Dose Level 4
Enrolled Subjects will receive a single-dose of DB-1303 at Dose Level 4 on Day 1 of each cycle Q3W
|
Biological: DB-1303
Administered IV |
Experimental: DB-1303 Dose Level 5
Enrolled Subjects will receive a single-dose of DB-1303 at Dose Level 5 on Day 1 of each cycle Q3W
|
Biological: DB-1303
Administered IV |
Experimental: DB-1303 Dose Expansion 1
Enrolled Subjects will receive a single-dose of DB-1303 on a selected dose level (RP2D) Day 1 of each cycle Q3W
|
Biological: DB-1303
Administered IV |
Experimental: DB-1303 Dose Expansion 2
Enrolled Subjects will receive a single-dose of DB-1303 on a selected dose level (RP2D) Day 1 of each cycle Q3W
|
Biological: DB-1303
Administered IV |
Experimental: DB-1303 Dose Expansion 3
Enrolled Subjects will receive a single-dose of DB-1303 on a selected dose level (RP2D) Day 1 of each cycle Q3W
|
Biological: DB-1303
Administered IV |
Experimental: DB-1303 Dose Expansion 4
Enrolled Subjects will receive a single-dose of DB-1303 on a selected dose level (RP2D) Day 1 of each cycle Q3W
|
Biological: DB-1303
Administered IV |
Experimental: DB-1303 Dose Expansion 5
Enrolled Subjects will receive a single-dose of DB-1303 on a selected dose level (RP2D) Day 1 of each cycle Q3W
|
Biological: DB-1303
Administered IV |
Experimental: DB-1303 Dose Level 6
Enrolled Subjects will receive a single-dose of DB-1303 at Dose Level 6 on Day 1 of each cycle Q3W
|
Biological: DB-1303
Administered IV |
Experimental: DB-1303 Dose Level 7
Enrolled Subjects will receive a single-dose of DB-1303 at Dose Level 7 on Day 1 of each cycle Q3W
|
Biological: DB-1303
Administered IV |
Experimental: DB-1303 Dose Expansion 6
Enrolled Subjects will receive a single-dose of DB-1303 on a selected dose level (RP2D) Day 1 of each cycle Q3W
|
Biological: DB-1303
Administered IV |
- Phase 1: Percentage of Participants with Dose-Limiting Toxicities (DLTs) as assessed by CTCAE v5.0. [ Time Frame: up to 21 days after C1D1 ]Percentage of participants in Part 1 with DLTs
- Phase 1: Percentage of Participants with Treatment Emergent Adverse Events (TEAEs) as assessed by CTCAE v5.0. [ Time Frame: Up to follow-up period, approximately 1 year post-treatment ]Percentage of participants with AEs in Part 1 graded according to NCI CTCAE v5.0
- Phase 1: Percentage of Participants with Serious Adverse Events (SAEs) as assessed by CTCAE v5.0. [ Time Frame: Up to follow-up period, approximately 1 year post-treatment ]Percentage of Participants with SAEs in Part 1 graded according to NCI CTCAE v5.0
- Phase 1: Maximum Tolerated Dose (MTD) of DB-1303 [ Time Frame: 12 months ]MTD on the data collected during Part 1
- Phase 1: Recommended Phase 2 Dose (RP2D) of DB-1303 [ Time Frame: 12 months ]RP2D of DB-1303 based on the data collected during Part 1
- Phase 2a: Percentage of Participants with Treatment Emergent adverse events (TEAEs) as assessed by CTCAE v5.0. [ Time Frame: Up to follow-up period, approximately 1 year post-treatment ]Percentage of participants with AEs in Part 2 graded according to NCI CTCAE v5.0
- Phase 2a: Percentage participants with Serious Adverse Events (SAEs) as assessed by CTCAE v5.0. [ Time Frame: Up to follow-up period, approximately 1 year post-treatment ]Percentage of participants with SAEs in Part 2 graded according to NCI CTCAE v5.0
- Phase 2a: Percentage of Objective Response Rate (ORR) as assessed by RECIST 1.1. [ Time Frame: Up to follow-up period, approximately 1 year post-treatment ]The percentage of subjects who had a best response rating of CR and PR, for Part 2 only which was maintained ≥4 weeks
- Phase 1 & Phase 2a: Pharmacokinetic-AUC [ Time Frame: Pre-Dose, 30 minutes post end of infusion, 4 hours, 8 hours, 24 hours, 72 hours, 7 days, 14 days post start of infusion at Cycle 1 and Cycle 3. Pre-dose and within 30 minutes post end of infusion up to Cycle 8, End of Treatment and Safety Follow-up Visit ]Area under the concentration-time curve from time 0 to infinity of DB-1303
- Phase 1 & Phase 2a: Pharmacokinetic-Cmax [ Time Frame: Pre-Dose, 30 minutes post end of infusion, 4 hours, 8 hours, 24 hours, 72 hours, 7 days, 14 days post start of infusion at Cycle 1 and Cycle 3. Pre-dose and within 30 minutes post end of infusion up to Cycle 8, End of Treatment and Safety Follow-up Visit ]Maximum observed plasma concentration (Cmax) of DB-1303
- Phase 1 & Phase 2a: Pharmacokinetic-Tmax [ Time Frame: Pre-Dose, 30 minutes post end of infusion, 4 hours, 8 hours, 24 hours, 72 hours, 7 days, 14 days post start of infusion at Cycle 1 and Cycle 3. Pre-dose and within 30 minutes post end of infusion up to Cycle 8, End of Treatment and Safety Follow-up Visit ]Time to Cmax of DB-1303
- Phase 1 & Phase 2a: Pharmacokinetic-T1/2 [ Time Frame: Pre-Dose, 30 minutes post end of infusion, 4 hours, 8 hours, 24 hours, 72 hours, 7 days, 14 days post start of infusion at Cycle 1 and Cycle 3. Pre-dose and within 30 minutes post end of infusion up to Cycle 8, End of Treatment and Safety Follow-up Visit ]Terminal elimination half-life
- Phase 1 & Phase 2a: Pharmacokinetic-Ctrough [ Time Frame: Pre-Dose, 30 minutes post end of infusion, 4 hours, 8 hours, 24 hours, 72 hours, 7 days, 14 days post start of infusion at Cycle 1 and Cycle 3. Pre-dose and within 30 minutes post end of infusion up to Cycle 8, End of Treatment and Safety Follow-up Visit ]Trough concentration of DB-1303
- Phase 1 & Phase 2a: Pharmacodynamics-ADA [ Time Frame: Before infusion on C1D1, C1D15, Before infusion on day 1 of C2, C4, C6, C8, C10 and every 4 cycles until end of treatment, EOT visit, Safety FU Visit, and 60 and 90 days after last dose (if possible) ]Data gathered from blood to determine Levels of anti-drug antibody (ADA) against DB 1303 in serum compared to baseline.
- Phase 2a: Disease Control Rate (DCR) as assessed by RECIST 1.1 [ Time Frame: Up to follow-up period, approximately 1 year post-treatment ]Proportion of participants who had a best response rating of CR or PR, or SD using RECIST V1.1.
- Phase 2a: Duration of Response (DoR) as assessed by RECIST 1.1 [ Time Frame: Up to follow-up period, approximately 1 year post-treatment ]The duration of time from date of first CR or PR to date of progressive disease or death due to any cause, whichever comes first using RECIST V1.1
- Phase 2a: Time to Response (TTR) as assessed by RECIST 1.1 [ Time Frame: Up to follow-up period, approximately 1 year post-treatment ]The duration of time when receiving the first dose of study drug to the first date that is evaluated as either CR or PR using RECIST V1.1
- Phase 2a: Time on Therapy [ Time Frame: Up to 21 days after the participant's last dose ]The duration of time from participant receiving first dose of study drug to the last dose + 21 days
- Phase 2a: Percent change in target lesions as assessed by RECIST 1.1 [ Time Frame: Up to follow-up period, approximately 1 year post-treatment ]The percent change in the participant's target lesions from baseline to last study scan using RECIST V1.1

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Has a pathologically documented HER2-positive or HER2-expressing advanced/unresectable, recurrent, or metastatic malignant solid tumor that is refractory to or intolerable with standard treatment, or for which no standard treatment is available.
- At least 1 measurable lesion (per RECIST 1.1)
- Provide signed informed consent
- ECOG performance status (PS) of 0-1.
- LVEF ≥ 50% by ECHO or MUGA
- Adequate organ functions
- Provide pre-existing diagnosis of HER2 status or resected tumor samples or undergo fresh tumor biopsy for HER2 testing.
- Life expectancy of ≥ 3 months.
Exclusion Criteria:
- History of symptomatic CHF (New York Heart Association [NYHA] classes II-IV) or serious cardiac arrhythmia requiring treatment.
- History of myocardial infarction or unstable angina within 6 months before Day 1.
- Average QTcF > 450 ms in males and > 470 ms in females
- History of clinically significant lung diseases
- Uncontrolled infection requiring IV antibiotics, antivirals, or antifungals.
- HIV infection with AIDS defining illness or active viral hepatitis.
- Clinically active brain metastases
- Unresolved toxicities from previous anticancer therapy, defined as toxicities not yet resolved to NCI-CTCAE version 5.0, Grade ≤ 1 or baseline.
- A known hypersensitivity to either the drug substances or inactive ingredients in the drug product.
- Multiple primary malignancies within 3 years, except adequately resected non- melanoma skin cancer, curatively treated in-situ disease, other solid tumors curatively treated, or contralateral breast cancer.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT05150691
Contact: Britney Winterberger | +1-513-403-8568 | britney.winterberger@tigermedgrp.com |

Responsible Party: | DualityBio Inc. |
ClinicalTrials.gov Identifier: | NCT05150691 |
Other Study ID Numbers: |
DB-1303-O-1001 |
First Posted: | December 9, 2021 Key Record Dates |
Last Update Posted: | April 26, 2023 |
Last Verified: | April 2023 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
HER2 HER2-positive HER2-positive Breast Cancer HER2-positive Gastric Cancer HER2-positive Endometrial Cancer HER2-positive Biliary Tract Cancer HER2-positive Advanced Solid Tumor HER2 low HER2 high metastatic cancer HER2-positive GEJ Uterine serous papillary carcinoma USPC recurrent cancer carcinoma |
neoplasms breast neoplasms gastrointestinal neoplasms endometrial neoplasms biliary tract neoplasms Antineoplastic Agents, Biological stomach cancer bile duct cancer Cholangiocarcinoma liver cancer liver neoplasms NSCLC Non-Small Cell Lung Cancer NSCLC HER2 mutation HER2 Low Breast Cancer |
Neoplasms |