A Phase 1 Clinical Study of NXP800 in Subjects with Advanced Cancers and Expansion in Subjects with Ovarian Cancer

Part A Inclusion Criteria:

• Provide written informed consent.

• 18 years old or older.

• Life expectancy of at least 12 weeks.

• Histologically- or cytologically-confirmed, advanced, metastatic, and/or progressivesolid tumors for whom there is no authorized or effective therapy available, or forwhom such therapies are considered inappropriate by the Investigator (in Part B,subjects with specific cancer types will be enrolled; Specific criteria will beintroduced in a protocol amendment).

• Measurable disease according to Response Evaluation Criteria in Solid Tumors (RECIST) Version 1.1.

• Eastern Cooperative Oncology Group (ECOG) performance status of ≤ 2.

Part A Exclusion Criteria:

• Radiotherapy (except for palliative reasons), endocrine therapy, chemotherapy, orinvestigational agent within 28 days, (42 days for nitrosoureas, mitomycin-C) offirst dose of NXP800. Subjects can continue to receive bisphosphonates due tometastatic bone disease or GnRH agonists if they have prostate cancer.

• Ongoing toxic manifestations of previous treatments > Grade 2.

• Subjects with treated brain metastases are eligible if there is no evidence ofprogression for at least 28 days after central nervous system (CNS) directedtreatment, as ascertained by clinical examination and brain imaging (magneticresonance imaging [MRI] or computed tomography [CT] scan) during the Screeningperiod.

• Female subjects who can become pregnant (or are already pregnant or lactating).

• Male subjects with partners of childbearing potential (unless they agree to takemeasures not to father children by using a barrier method of contraception (condomplus spermicide) or to sexual abstinence).

Part B Inclusion Criteria:

• Provide written informed consent.

• 18 years old or older.

• Subjects with the following ARID1a mutated, ovarian/fallopian tube/primaryperitoneal cancer histologies (ARID1a mutation status determined by a DNA-based NextGeneration Sequencing test):

• Clear cell ovarian carcinoma (≥ 50% clear cell carcinoma with no serousdifferentiation)

• Endometrioid ovarian carcinoma

• Subjects must have disease progression within 6 months (182 days) from completion ofplatinum-based therapy (6 months should be calculated from the date of the lastadministered dose of platinum therapy to the date of radiographic imaging showingprogression)

• Measurable disease according to Response Evaluation Criteria in Solid Tumors (RECIST) Version 1.1.

• Subjects with a BRCA mutation must have received prior treatment with a PARPinhibitor.

• Subjects must have received at least 1 but not more than 3 prior systemic lines ofanticancer therapy, including at least 1 line of therapy containing bevacizumab.

• Adjuvant + neoadjuvant are considered one line of therapy

• Maintenance therapy (i.e., bevacizumab, PARP inhibitors) will be considered aspart of the preceeding line of therapy and are not counted independently.

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

• Subjects must have a sufficient archival Formalin-Fixed Paraffin-Embedded (FFPE)tissue specimen, or be willing to consent to a fresh tissue biopsy during the study.

Part B Exclusion Criteria:

• Subjects with disease that did not respond to, or has progressed during or within 4weeks of the last dose of first-line platinum containing chemotherapy.

• Radiotherapy (except for palliative reasons), endocrine therapy, chemotherapy, orinvestigational agent within 28 days, (42 days for nitrosoureas, mitomycin-C) offirst dose of NXP800.

• Ongoing toxic manifestations of previous treatments > Grade 2, with the exception ofalopecia.

• Subjects with treated brain metastases are eligible if there is no evidence ofprogression for at least 12 weeks while off corticosteroids after central nervoussystem (CNS) directed treatment, as ascertained by clinical examination and brainimaging (magnetic resonance imaging [MRI] or computed tomography [CT] scan) duringthe Screening period.

• Female subjects who can become pregnant (or are already pregnant or lactating).