A Dose Escalation and Cohort Expansion Study of KB-0742 in Participants With Relapsed or Refractory Solid Tumors or Non-Hodgkin Lymphoma

Inclusion Criteria:

Males or females ≥ 18 years old (Parts 1 and 2A); males or females ≥ 12 years old and with a body weight ≥ 40 kg are eligible to enroll with tumor types including soft-tissue sarcomas, Ewing's sarcoma, alveolar rhabdomyosarcoma, NUT midline carcinoma (NMC), or chordoma (Part 2B)
Willing and able to provide consent (and assent for participants between the ages of 12 to <18)

Part 1: Participants who meet at least 1 of the following criteria:

Any relapsed/refractory (R/R) solid tumor with readily accessible biopsy sites and consenting to 1 baseline and 1 on-treatment biopsy if deemed feasible to perform.

Tumor type of interest (see list below) with measurable disease per Response Evaluation Criteria in Solid Tumors 1.1 (RECIST 1.1) or Positron Emission Tomography (PET) Response Criteria in Solid Tumors (PERCIST) 1.0 for solid tumors or by Lugano Classification or Modified Weighted Assessment Tool (mSWAT) for non-Hodgkin lymphoma AND at least 1 measurable scan per one of the above criteria prior to the most recent scan to document the rate of tumor growth before the initiation of study treatment. Tumor types of interest (R/R without other available therapeutic options) are:

Small cell lung cancer (SCLC)
Epithelial ovarian cancer, triple negative breast cancer (TNBC), or non-small cell lung cancer (NSCLC)
Diffuse large B-cell lymphoma with documented MYC translocation or Burkitt's lymphoma (as determined by local testing)
Sarcoma with documented transcription factor fusion (as determined by local testing)
Chordoma, NUT midline carcinoma, or adenoid cystic carcinoma
Part 2, Cohort A: Participants with histologically or cytologically confirmed solid tumors who have failed, are intolerant to or are considered ineligible for standard-of-care anti-cancer treatments.

Note: Part 2, Cohort A, will include participants with relapsed or refractory solid tumors including approximately 10 participants each with NSCLC, triple-negative breast cancer and ovarian cancer (MYC-dependent tumor types).

• Part 2, Cohort B: Participants with histologically or cytologically confirmed SCLC or soft-tissue sarcomas with defined transcription factor oncogenic drivers as determined locally, including (but not limited to) chordomas, Ewing's sarcoma or alveolar rhabdomyosarcoma as well as NUT midline carcinomas (NMC) or adenoid cystic carcinomas, without access to or intolerant of other approved therapies.

For both Parts 1 and 2:

Access to a tumor sample for central laboratory testing
Eastern Cooperative Oncology Group Performance Status (ECOG PS) 0 or 1
Evaluable or measurable disease, per RECIST 1.1 or PERCIST 1.0 for solid tumors or the Lugano Classification or mSWAT for non-Hodgkin lymphoma
Adequate bone marrow and organ function
Recovery from treatment-related toxicities from prior therapies to National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) Grade ≤ 1 or to baseline level
Must agree to use highly effective birth control during the trial and for at least 3 months after the last dose of study drug; female participants cannot be pregnant or breastfeeding

Exclusion Criteria:

Any other anti-cancer therapies including chemotherapy, immunotherapy, or hormonal therapy within 4 weeks or 5 half-lives (whichever is shorter)
History of surgery (except for diagnostic purposes) or non-palliative radiotherapy within 4 weeks
History of allogeneic transplantation within 6 months
Active central nervous system (CNS) involvement by the underlying malignancy; previously treated CNS metastatic disease is permitted with magnetic resonance imaging (MRI) documentation of stable disease for at least 3 months prior to study start
History of stroke or intracranial hemorrhage within ≤6 months
History of seizure disorder, ie, recurrent seizures with an underlying etiology and requiring ongoing anti-epileptic medication
Current use of medications associated with seizure risk unless approved by Medical Monitor
Active infections requiring systemic antibiotic, antiviral or antifungal therapy
Known active coronavirus disease 2019 (COVID-19)
Clinically significant heart disease
Uncontrolled hypertension
Prolongation of QT interval at baseline
Known human immunodeficiency virus (HIV), hepatitis B, or hepatitis C infection
Significant concurrent, uncontrolled medical condition including, but not limited to, renal, hepatic, hematologic, gastrointestinal, endocrine, pulmonary, neurological, cerebral or psychiatric disease