Trial of T-DXd Versus SoC Chemotherapy as Adjuvant Treatment in Endometrial Cancer

Overview

Sponsor-declared trial summary

Key facts

Sponsor

Daiichi Sankyo Inc.

Participant type

Patients

Age range

18-64 years, 65+ years

Gender

Female

Therapeutic area

Diseases [C] - Neoplasms [C04]

Trial duration

12 Mar 2026 → ongoing

Decision date (initial)

2025-12-15

Transition trial

No

Low-intervention

No

Rare-disease indication

No

Vulnerable population

No

Funding sources

Daiichi Sankyo, Inc

External identifiers

EU CT number

2024-519444-33-00

ClinicalTrials.gov

NCT07022483

Trial design

CTIS Part I — objectives, methods, condition coding

Main objective

Scope: Pharmacokinetic, Efficacy, Pharmacodynamic, Safety, Pharmacoeconomic

To compare the efficacy of T-DXd versus SoC as measured by DFS, as assessed by BICR or by histopathologic confirmation of disease recurrence per local assessment in the HER2 IHC 3+/2+ population

Secondary objectives 10

1. To compare the efficacy of T-DXd versus SoC as measured by OS in the HER2 IHC 3+/2+ population
2. To compare efficacy of T-DXd versus SoC as measured by DFS, as assessed radiographically by investigator or by histopathologic confirmation of disease recurrence per local assessment in the HER2 IHC 3+/2+ population
3. To compare the efficacy of T-DXd versus SoC with respect to distant metastatic recurrence as assessed radiologically by BICR or by histopathologic confirmation of disease recurrence per local assessment in the HER2 IHC 3+/2+ population.
4. To compare the efficacy of T-DXd versus SoC with respect to local recurrence as assessed radiographically by BICR or by histopathologic confirmation of disease recurrence per local assessment in the HER2 IHC 3+/2+ population.
5. To compare the efficacy of T-DXd versus SoC with respect to regional recurrence as assessed radiographically by BICR or by histopathologic confirmation of disease recurrence per local assessment in the HER2 IHC 3+/2+ population.
6. To evaluate the safety and tolerability of T-DXd versus SoC in the HER2 IHC 3+/2+ population
7. To evaluate patient-reported HRQoL in participants treated with T-DXd versus SoC in the HER2 IHC 3+/2+ population
8. To evaluate patient-reported symptom burden in participants treated with T-DXd versus SoC in the HER2 IHC 3+/2+ population
9. To evaluate the PK of T-DXd, total anti-HER2 antibody, and DXd in the HER2 IHC 3+/2+ population
10. To assess the immunogenicity of T-DXd in the HER2 IHC 3+/2+ population

Conditions and MedDRA coding

HER2-expressing endometrial cancer (IHC 3+/2+)

Regulatory references

Scientific advice from competent authorities

European Medicines Agency

Plan to share IPD

Yes

IPD plan description

De-identified individual participant data (IPD) and applicable supporting clinical trial documents may be available upon request at https://vivli.org/. In cases where clinical trial data and supporting documents are provided pursuant to our company policies and procedures, Daiichi Sankyo will continue to protect the privacy of our clinical trial participants. Details on data sharing criteria and the procedure for requesting access can be found at this web address: https://vivli.org/ourmember/daiichi-sankyo/

Eligibility criteria

Principal inclusion / exclusion criteria as submitted by sponsor

Inclusion criteria 17

1. Sign and date the Tissue SCR ICF, prior to HER2 central testing. Sign and date the main SCR ICFs, prior to the start of any trial-specific qualification procedures not included in the Tissue SCR ICF. Consent to optional PGx prior to any PGx procedures.
2. Adults ≥18 years at the time the ICF is signed (Please follow local regulatory requirements if the legal age of consent for trial participation is >18 years old)
3. Has histologically confirmed diagnosis of epithelial endometrial carcinoma. All histology’s are allowed except for sarcomas (carcinosarcomas are allowed).
4. Is newly diagnosed FIGO 2023 Stage IIC (including Stage IICmp53abn) or Stage III
5. Has HER2-expression (IHC 3+/2+) per 2016 ASCO-CAP gastric cancer IHC scoring guidelines as confirmed by central laboratory testing.
6. Has adequate archived tumor tissue sample (sample from surgery is strongly recommended) available for assessment of HER2 status by central laboratory.
7. Has an MMR IHC local test result from an approved and/or validated test, according to the local regulations.
8. Is eligible for combination treatment with carboplatin and paclitaxel as adjuvant therapy per SoC and Investigator discretion
9. Has undergone curative intent surgery that included hysterectomy and bilateral salpingo- oophorectomy. Pelvic lymph node sampling, para-aortic lymph node sampling, including sentinel lymph node, and lymph node dissection are optional but strongly encouraged.
10. Is disease-free with no evidence of loco-regional disease or distant metastasis post- operatively on imaging assessed by investigator and confirmed by BICR.
11. Trial intervention to start within 8 weeks of endometrial cancer surgery date
12. Has not received any radiotherapy or systemic therapy, including immunotherapy, hormonal therapy, radiosensitizer chemotherapy or HIPEC, in any setting including the neoadjuvant setting for endometrial cancer.
13. Has LVEF ≥ 50% within 28 days before randomization.
14. ECOG performance status of 0 or 1 assessed no more than 14 days prior to randomization.
15. Has adequate organ and bone marrow function as assessed by local laboratory within 14 days prior to randomization as defined in the protocol. Organ and bone marrow function criteria must also be met when laboratory tests are repeated within 72 hours of initiation of trial intervention as appropriate.
16. Has adequate treatment washout period before randomization as defined in the protocol.
17. Is willing and able to comply with scheduled visits, drug administration plan, laboratory tests, other trial procedures and trial restrictions.

Exclusion criteria 21

1. Has uterine mesenchymal tumor such as an endometrial stromal sarcoma, leiomyosarcoma, or other types of pure sarcomas. Adenosarcomas are also not allowed.
2. Has recurrent or FIGO 2023 Stage IV.
3. Has measurable residual tumor after surgery as determined by BICR assessment.
4. Is known to have a POLE mutation from an approved and/or validated local test, according to local regulations, if available
5. Has a medical history of MI within 6 months before randomization/enrollment, symptomatic CHF (NYHA Class II to IV). Participants with Troponin levels above ULN at SCR (as defined by the manufacturer), and without any MI related symptoms should have a cardiologic consultation during SCR Period to rule out MI.
6. Has a QTcF prolongation to > 480 msec based on average of the SCR triplicate12-lead ECG.
7. Any of the following within the past 6 months prior to enrollment: cerebrovascular accident, transient ischemic attack, or other arterial thromboembolic event.
8. Has a history of (noninfectious) ILD/pneumonitis that required corticosteroids, has current ILD/pneumonitis, or where suspected ILD/pneumonitis cannot be ruled out by imaging at SCR.
9. Clinically severe pulmonary compromise resulting from intercurrent pulmonary illnesses including, but not limited to, any underlying pulmonary disorder (ie, pulmonary emboli within 3 months of the trial enrollment, severe asthma, severe COPD, restrictive lung disease, pleural effusion, etc.) and any autoimmune, connective tissue, or inflammatory disorder with potential pulmonary involvement (eg, rheumatoid arthritis, Sjogren’s syndrome, sarcoidosis, etc.), or prior pneumonectomy.
10. History of other active malignancy within 3 years prior to enrollment, with the exception of those with a negligible risk of metastasis or death (eg, 5-year OS rate >90%) and treated with expected curative outcome (such as adequately treated carcinoma in situ of the cervix, nonmelanoma skin carcinoma, ductal carcinoma in situ).
11. History of hypersensitivity to the trial intervention or their excipients or any known contraindication (included in the approved local labels) to treatment with, including hypersensitivity to, the trial intervention.
12. History of severe hypersensitivity reactions to other monoclonal antibodies.
13. Has any evidence of severe or uncontrolled systemic diseases (including active bleeding diatheses or active infection, substance abuse) or other factors that, in the Investigator's opinion, make it undesirable for the participant to participate in the trial or which would jeopardize compliance with the protocol. SCR for chronic conditions is not required.
14. Has an uncontrolled infection requiring systemic antibiotics, antivirals or antifungals. Participant with localized fungal infections of skin or nails are eligible.
15. Has active or uncontrolled HBV infection. Hepatitis B SCR testing is required. Please see the protocol for more details.
16. Has active or uncontrolled hepatitis C virus infection. Hepatitis C SCR testing is required. Please see the protocol for more details.
17. Has active or uncontrolled HIV infection. Participants must be tested for HIV viral load during the SCR Period if acceptable by local regulations or IRBs/IECs. Please see the protocol for more details.
18. Psychological, social, familial, or geographical factors that would prevent regular follow up.
19. Prior or ongoing clinically relevant illness, medical condition, surgical history, physical finding, or laboratory abnormality that, in the investigator’s opinion, could affect the safety of the participant; alter the absorption, distribution, metabolism, or excretion of the trial intervention; or confound the assessment of trial results.
20. Has a history of receiving live-attenuated vaccine (mRNA and replication-deficient adenoviral vaccines are not considered attenuated live vaccines) within 30 days prior to the first exposure to trial intervention.
21. Unresolved toxicities from previous anticancer therapy, defined as toxicities (other than alopecia) not yet resolved to NCI-CTCAE Version 5.0, Grade ≤1 or baseline. Please see the protocol for more details.

Endpoints

Primary and secondary outcome measures (English text)

Primary endpoints 1

1. DFS is defined as time interval from the date of randomization to the first documented local-regional recurrence, distant metastasis, or death due to any cause, whichever occurs first. DFS will be assessed radiographically by BICR or by histopathologic confirmation of disease recurrence per local assessment.

Secondary endpoints 10

1. OS is defined as the time interval from the date of randomization to the date of death due to any cause.
2. DFS is defined as the time from randomization to the first documented local-regional recurrence, distant metastasis or death due to any cause, whichever occurs first. DFS will be assessed radiographically by investigator or by histopathologic confirmation of disease recurrence per local assessment.
3. Distant metastatic recurrence is defined as recurrence outside of vagina, pelvis, or pelvic lymph nodes.
4. Local recurrence is defined as recurrence in the vagina as assessed radiologically by BICR or by histopathologic confirmation of disease recurrence per local assessment
5. Regional recurrence is defined as recurrence in the pelvis or pelvic lymph nodes as assessed radiologically by BICR or by histopathologic confirmation of disease recurrence per local assessment
6. Incidence of TEAEs, SAEs, TEAEs associated with dose modifications, AESIs, TEAEs with death outcome, and changes from baseline in vital signs, clinical laboratory results, ECGs, ECHO/MUGA, and ophthalmologic assessments
7. Change from baseline and time to deterioration for the following PRO questionnaire: EORTC QLQ-C30 GHS/overall QoL, physical
8. Change from baseline and time to deterioration for the following PRO questionnaires: EORTC QLQ-EN24: Back and pelvic pain (ENBP), tingling/numbness (ENTN), muscular pain (ENM)
9. Serum concentrations of T-DXd, total anti-HER2 antibody and DXd.
10. ADA incidence: The proportion of participants having treatment-emergent ADA. Titer and nAb may be determined when ADA is positive.

Investigational products

Investigational medicinal products (IMPs), comparators, placebo, auxiliary

Test 1

Comparator 4

Sponsors and contacts

Sponsor organisations, regulatory contacts, third parties

Daiichi Sankyo Inc.

Sponsor organisation

Daiichi Sankyo Inc.

Address

211 Mount Airy Road

City

Basking Ridge

Postcode

07920-2311

Country

United States

Scientific contact point

Organisation

Daiichi Sankyo Inc.

Contact name

Clinical trial office

Public contact point

Organisation

Daiichi Sankyo Inc.

Contact name

Clinical trial office

Third parties 6

Locations

7 EU/EEA countries · 68 investigational sites

By country

Investigational sites

Country notifications

Trial-start, recruitment-start, end and early-termination notifications submitted per Member State

Results and documents

Annex IV summary of results, Annex V layperson summary, and all documents registered in CTIS for this trial

Documents 172 files

Public protocol annexes, IB summaries, regulatory submissions and post-authorisation documents registered in CTIS.

Application history

4 submissions — initial application plus substantial / non-substantial modifications