Rovalpituzumab Tesirine in Delta-Like Protein 3-Expressing Advanced Solid Tumors

This is a multicenter, open-label study involving multiple specific advanced solid tumor
types, consisting of a dose escalation Part A followed by an expansion Part B. Cancer
subtypes will be studied in separate disease-specific cohorts in both Parts. Eight separate
cohorts will enroll malignant melanoma, medullary thyroid cancer (MTC), glioblastoma, large
cell neuroendocrine carcinoma (LCNEC), neuroendocrine prostate cancer (NEPC), high-grade
gastroenteropancreatic (GEP), neuroendocrine carcinoma (NEC), other NEC, and solid tumors
other than the above.

Inclusion Criteria:

- Histologically confirmed, unresectable advanced solid malignancy with documented
disease progression after at least 1 prior systemic therapy

- Measurable disease as defined by RECIST 1.1

- DLL3-expressing malignancy based on central immunohistochemical (IHC) testing of
representative baseline tumor tissue (archived tissue or on-study biopsy). Positive is
defined as staining in ≥ 1% of tumor cells.

- Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1

- Minimum life expectancy of at least 12 weeks

- Subjects with a history of central nervous system (CNS) metastases must have
documentation of stable or improved brain imaging for at least 2 weeks after
completion of definitive treatment and within 2 weeks prior to first dose of Study
Drug, off or on a stable dose of corticosteroids. Definitive treatment may include
surgical resection, whole brain irradiation, and/or stereotactic radiation therapy.
(Applicable to tumor types of non-CNS primary origin only)

- Recovery to Grade 1 of any clinically significant toxicity (excluding alopecia) prior
to initiation of study drug administration

- Adequate hematologic and organ function as confirmed by laboratory values

- Last dose of any prior therapy administered by the following time intervals before the
first dose of study drug:

1. Chemotherapy, small molecule inhibitors, radiation, and/or other investigational
anticancer agents (excluding investigational monoclonal antibodies): 2 weeks.

2. Immune-checkpoint inhibitors (e.g., anti-PD-1, anti-PD-L1, or anti-CTLA-4),
monoclonal antibodies, antibody-drug conjugates, radioimmunoconjugates, or T-cell
or other cell-based therapies: 4 weeks (2 weeks with documented disease
progression).

- Females of childbearing potential must have a negative beta human chorionic
gonadotropin (β-hCG) pregnancy test result within 7 days prior to the first dose of
study drug. Females of non-childbearing potential are those who are postmenopausal
greater than 1 year or who have had a bilateral tubal ligation or hysterectomy.

Exclusion Criteria:

- Any significant medical condition, including any suggested by screening laboratory
findings that, in the opinion of the investigator or sponsor, may place the subject at
undue risk from the study, including but not necessarily limited to uncontrolled
hypertension and/or diabetes, clinically significant pulmonary disease (e.g., chronic
obstructive pulmonary disease requiring hospitalization within 3 months) or
neurological disorder (e.g., seizure disorder active within 3 months).

- Documented history of a cerebral vascular event (stroke or transient ischemic attack),
unstable angina, myocardial infarction, or cardiac symptoms consistent with New York
Heart Association (NYHA) Class III-IV (see Appendix 12.4) within 6 months prior to
their first dose of study drug.

- Recent or ongoing serious infection, including:

1. Any active grade 3 or higher (per NCI CTCAE version 4.03) viral, bacterial, or
fungal infection within 2 weeks of the first dose of the study drug. Routine
antimicrobial prophylaxis is permitted.

2. Known seropositivity for or active infection by human immunodeficiency virus
(HIV).

3. Active Hepatitis B (by surface antigen expression or polymerase chain reaction)
or C (by polymerase chain reaction) infection or on hepatitis-related antiviral
therapy within 6 months of first dose of study drug.

- Women who are pregnant or breastfeeding

- Systemic therapy with corticosteroids at >20 mg/day prednisone or equivalent within 1
week prior to the first dose of study drug

- History of another invasive malignancy that has not been in remission for at least 3
years. Exceptions to the 3year limit include non-melanoma skin cancer, curatively
treated localized prostate cancer, ductal carcinoma in situ, and cervical cancer in
situ on biopsy or squamous intraepithelial lesion on PAP smear.

- Prior exposure to a pyrrolobenzodiazepine (PBD)-based drug, prior participation in a
rovalpituzumab tesirine clinical trial, or known hypersensitivity to rovalpituzumab
tesirine or excipient contained in the drug formulation, unless undergoing retreatment
with rovalpituzumab tesirine in the context of this protocol