Inclusion Criteria. Participants must meet all of the following criteria to be eligible for enrollment into the
study:
1. Sign and date the informed consent form prior to the start of any study-specific
qualification procedures. A separate tissue screening consent will be obtained from
all subjects to meet the baseline tumor tissue requirement.
2. Participants aged ≥18 years (follow local regulatory requirements if the legal age of
consent for study participation is >18 years old).
3. Has locally advanced unresectable or metastatic disease (not curable by surgery or
radiation) as follows:
Cutaneous (acral and non-acral) melanoma. 1. Histologically or cytologically confirmed cutaneous (acral or non-acral) melanoma. 2. Disease progression while on or after having received treatment with ≥1 prior
line of anti-programmed cell death protein (PD-1) or anti-programmed death-ligand
1 (PD-L1) based therapy (previous use of other immune checkpoint inhibitors
[ICIs] [ie, anti-CTLA4, anti- LAG-3] is acceptable). Prior anti-PD-(L)1 therapy
in the adjuvant setting is allowed if there is recurrence within 12 weeks of the
last dose. If the participant had BRAFm melanoma, they must have had disease
progression on BRAF/MEK inhibitor therapy as well.
Squamous cell carcinomas of the head and neck. 3. Squamous cell carcinoma of the head and neck (with a primary location of oral
cavity,oropharynx, larynx, hypopharynx) that is human papillomavirus (HPV)
positive or negative (as determined by local standard). Excludes tumor location
in the nasopharynx, nasal cavity, paranasal sinuses, and unknown primary
locations.
4. Disease progression after having received treatment with ≥1 and <3 prior lines of
systemic therapy in the unresectable recurrent or metastatic setting.
Must have had disease progression on anti-PD-(L)1 (either as monotherapy or in
combination with chemotherapy or other therapies). Must also have had disease
progression on a platinum-based chemotherapy (PBC) regimen either in the
recurrent or metastatic setting or in the locally advanced setting with curative
intent.
Gastric or GEJ adenocarcinoma. 5. Tumor tissue must be confirmed as negative for HER2 expression
(immunohistochemistry [IHC] 0/1+ or IHC 2+/in situ hybridization negative) as
classified by American Society of Clinical Oncology/College of American
Pathologists (ASCO-CAP) guidelines and determined prior to enrollment by
assessment in a local laboratory that is Clinical Laboratory Improvement
Amendments certified (US sites) or accredited based on specific country
regulations.
6. Disease progression after having received treatment with ≥2 prior lines of
therapy that include PBC with or without anti-PD-1 therapy.
Ovarian Carcinoma. 7. Pathologically documented high-grade serous epithelial ovarian cancer, primary
peritoneal cancer, or fallopian tube cancer.
8. Documented disease progression ≥4 weeks after the last dose of PBC and <6 months
of last dose of PBC in the advanced or metastatic setting. Prior use of folate
reductase alpha targeting antibody-drug conjugate (ADC) (ie, mirvetuximab
soravtansine) is allowed.
Cervical Cancer. 9. Pathologically or cytologically documented recurrent or persistent squamous,
adenosquamous, or adenocarcinoma of the uterine cervix.
10. Disease progression after having received ≥1 line of systemic therapy in the
recurrent or metastatic setting. This may include prior anti-PD-(L)1 treatment
and/or tissue factor directed ADC (tisotumab vedotin [TV]) per regional standard
of care.
Endometrial Cancer. 11. Pathologically or cytologically documented endometrial cancer (carcinoma of any
histological sub-type or endometrial carcinosarcoma), irrespective of
microsatellite instability (MSI) or mismatch repair (MMR) status.
12. Documented disease progression after having received ≥1 prior line of therapy
(maximum of 3) PBC containing systemic treatment and an anti-PD(L)-1
therapy-containing regimen (combined or sequential) in the advanced/metastatic
setting.
Bladder Cancer. 13. Pathologically or cytologically documented locally advanced/unresectable or
metastatic urothelial carcinoma of the bladder, renal pelvis, ureter, or urethra.
Histological variants are allowed if urothelial histology is predominant. Small
cell/neuroendocrine tumors are not allowed even if mixed histology.
14. Relapsed or progressed after treatment with ≥1 prior line of therapy (maximum of
3) that contains anti-PD-(L)1 therapy in the perioperative or metastatic setting.
At least 1 line of therapy must also contain one of the following treatment
modalities: chemotherapy or enfortumab vedotin. Prior fibroblast growth factor
receptor (FGFR)-inhibitor treatment for those who are eligible are allowed.
- - Required treatments can be given in combination or sequentially.
- - Prior cisplatin-based therapy or PD-(L)1 inhibitor therapy given for the
treatment of muscle invasive urothelial carcinoma is counted as 1 line of
therapy.
- - The same regimen administered twice in different disease settings will be
counted as 1 line of prior therapy.
- - A minimum of 20 subjects in the second-line setting who have previously
received enfortumab vedotin and pembrolizumab in combination will be
enrolled.
Esophageal Carcinoma. 15. Pathologically or cytologically documented esophageal squamous cell carcinoma.
16. Must have documented disease progression after having received 2 prior lines of
therapy including previous PBC with or without an anti-PD-1 therapy-containing
regimen (combined or sequential) in the advanced/metastatic setting.
Pancreatic Carcinoma. 17. Pathologically or cytologically documented unresectable or metastatic pancreatic
adenocarcinoma.
18. Relapsed or disease progression after having received 1 prior line of systemic
therapy in the locally advanced/metastatic setting.
Prostate Cancer. 19. Pathologically or cytologically documented unresectable locally advanced or
metastatic castration-resistant prostate cancer (CRPC).
20. Adenocarcinoma of the prostate without neuroendocrine differentiation or small
cell histology.
21. Surgically or medically castrated, with testosterone levels of <50 ng/dL.
22. Documented objective progression as determined by radiographic progression for
subjects with measurable disease after androgen deprivation.
23. Relapsed or disease progression after having received treatment with ≥1 of the
following novel hormonal agents: abiraterone, enzalutamide, apalutamide, or
darolutamide.
24. Relapsed or disease progression after having received ≥1 cytotoxic chemotherapy
regimen that included a taxane.
4. Has ≥1 measurable lesion on CT or MRI as per RECIST v1.1 by investigator assessment.
Prostate cancer participants with bone only disease may be eligible.
5. Provides a pretreatment tumor tissue sample of sufficient quantity, as defined in the
Study Laboratory Manual. The following tissue samples can be provided as the
pretreatment tumor tissue sample:
1. Tissue collected from a biopsy (from ≥1 lesion not previously irradiated)
performed since progression while on or after treatment with the most recent
systemic cancer therapy regimen and prior to signing of the tissue ICF. OR. 2. Pretreatment tumor biopsy from ≥1 lesion not previously irradiated and amenable
to sampling after signing of the tissue ICF. The pretreatment tissue requirement
may be waived after discussion and agreement with the Sponsor.
6. Has Eastern Cooperative Oncology Group performance status (ECOG PS) of 0 or 1 at
screening.
Exclusion Criteria. Participants who meet any of the following criteria will be disqualified from entering the
study:
1. Has HER2-positive gastric cancer as classified by ASCO-CAP guidelines and determined
prior to enrollment by assessment in a local laboratory that is Clinical Laboratory
Improvement Amendments certified (US sites) or accredited based on specific country
regulations.
2. Has nasopharyngeal cancer.
3. Has mucosal or uveal melanoma.
4. Has a history of (non-infectious) interstitial lung disease (ILD), that required
corticosteroids, has current ILD/pneumonitis, or suspected ILD/pneumonitis cannot be
ruled out by imaging at screening.
5. Has clinically severe respiratory compromise (based on the investigator's assessment)
resulting from intercurrent pulmonary illnesses. 6. Is receiving chronic systemic corticosteroids dosed at >10 mg prednisone or equivalent
anti-inflammatory activity or any form of immunosuppressive therapy prior to Cycle 1
Day 1.
Participants who require use of bronchodilators, inhaled or topical steroids, or local
steroid injections may be included in the study.
7. Had prior treatment with an anti-HER3 antibody and/or antibody-drug conjugate (ADC)
that consists of an exatecan derivative that is a topoisomerase I inhibitor (eg,
trastuzumab deruxtecan).
8. Has history of other active malignancy within 3 years prior to Cycle 1 Day 1, except
the following:
1. Adequately treated nonmelanoma skin cancer. 2. Adequately treated intraepithelial carcinoma of the cervix. 3. Any other curatively treated in situ disease. 9. Has any evidence of severe or uncontrolled diseases (eg, active bleeding diatheses,
active serious infection) psychiatric illness/social situations, geographical factors,
substance abuse, or other factors that, in the investigator's opinion, make it high
risk for the subject to participate in the study or that would jeopardize compliance
with the protocol. 10. Has previously received irinotecan treatment in the advanced or metastatic disease
setting.
