First in Human Multicenter Open Name Dose-increase, Consolidation Method to Study Safety Drug-level in Blood & Drug Metabolism Clinical Activity of Oral JBI-778 in Lung Cancer Patients With, Without Brain Metastasis IDH Mutated WHO Grade 3,4 Recurrent Glioma, Salivary Glands Tumor

Dose-Escalation:

The initial dose escalation up to cohort 3 (estimate to be 160mg) or until the pharmacologically active dose is reached, whichever comes first as determined by the safety committee will be performed only in EGFR mutant NSCLC patients with or without stable cerebral metastases and ACC patients. Once this dose level is reached IDH mutated WHO grade 3 /4 glioma patients will be added. The starting dose of JBI-778 is 40 mg orally, once daily in 21-day treatment cycles using a 3+3 design. Dose escalation will be 100% until dose level 3 (i.e., 160 mg) afterwards, a maximum of 33%-75% dose increment will be implemented (up to 75% dose increment if no dose limiting toxicity (DLT), but 33% dose increment if one DLT is observed in the previous dose level, applicable to any dose level not just after 160mg), rounded up or down based on capsule strength. With these restrictions, the next dose to be studied will be determined by the sponsor with approval by the Safety Review Committee (SRC). In the event that any DLTs occur at the starting dose in 2 patients, and with the approval of the SRC, a 20 mg once daily dose level will be evaluated using a 3+3 design. If 20 mg once daily is not tolerated, no further patients will be recruited, and the study will be terminated. In addition to the PK evaluation, patients in dose-escalation will provide pre-treatment and on treatment tissue and/or liquid biopsies to aid in the assessment.

In the 3+3 design, if 3 patients at a dose level complete the DLT evaluation period with no DLT, that dose level of JBI-778 will be deemed safe, and another 3 patients will be treated at the next higher dose level. If 1 of the first 3 patients experience a DLT, 3 more patients will be treated at the same JBI-778 dose level. If 2 or more of the 3 to 6 patients in any dose level experience a DLT, dosing will stop at that level, and either the previous dose level will be considered the Maximum Tolerated Dose (MTD) or intermediate doses may be explored to determine MTD, especially if the difference between the non-tolerated dose and the previous dose is > 50%.

Dose-escalation will continue until any of the following events occur:

• The highest planned dose level is determined to be safe and tolerable (Minimum of 6 DLT evaluable patients).
• An MTD is identified. Additional dose levels may be explored based on emerging data (Additional patients (up to 6 patients may be enrolled in 1 or more dose levels that have been shown to be safe and tolerable, defined as backfill enrolment). This backfill enrolment will be done to better estimate the RP2D and to better characterize the safety, efficacy, PK and pharmacodynamics (PD) for JBI 778 and may be concurrent with dose-escalation to identify the MTD. Study patients who do not complete the DLT period for reasons other than study drug toxicity will be replaced. All patients will be assessed for a response using relevant RECIST 1.1 and RANO criteria. Clinical status will be assessed by the NANO instrument. Intra-patient dose-escalations are allowed in this study. Patients who complete the DLT period, tolerate the dose, and have been on the treatment for ≥ 2 cycles without significant toxicities may proceed to a higher dose level for the following treatment cycle if the next dose cohort is deemed safe (For both acute and cumulative toxicities) at that time by the Safety Review Committee (SRC), and after consultation with the Sponsor if the patient has not experienced any ≥ Grade 2 adverse events (deemed treatment-related by the Investigator) during entire prior treatment. The maximum Intra-patient Dose-Escalation level should be one level below the current actively enrolling dose level if tolerability based on the protocol defined criteria have not yet been established. Patients who do not proceed to a higher dose may continue to receive additional cycles at their original dose, based on the decision of the investigator and concurrence by the SRC. An SRC will have oversight of safety and will meet at the end of each cohort and approximately quarterly and as needed during the dose-escalation phase to review cumulative toxicity data, make recommendations to the Sponsor regarding ongoing safety and dose-escalations. The SRC may recommend protocol amendments to maintain patient safety at any stage. In addition, any serious adverse events (SAEs) will be forwarded to the SRC upon occurrence. Safety and tolerability of JBI-778 will be characterized by adverse event and serious adverse event type, severity (graded using the National Cancer Institute Common Terminology Criteria for Adverse Events [NCI CTCAE] Version 5.0), timing, and relationship to study therapy, and laboratory abnormalities in the first and in subsequent cycles. Administration of JBI-778 may continue until evidence of disease progression, intolerance to study medication, or withdrawal of consent. Stable or responding patients who experience DLTs may continue therapy once DLTs have resolved.

Inclusion criteria

• Male or female participants aged ≥18 years.
• Histologically or cytologically confirmed:

• EGFR-mutated non-small cell lung cancer (NSCLC) with or without brain metastases previously treated with an EGFR inhibitor; or
• IDH-mutated WHO Grade 3/4 recurrent glioma; or
• Adenoid cystic carcinoma (ACC) with recurrent, metastatic, or advanced incurable disease.
• At least one measurable lesion according to RECIST v1.1 and/or RANO criteria, as applicable.
• ECOG performance status ≤2.
• Adequate hematologic, hepatic, renal, and coagulation function.
• Resolution of clinically significant toxicities from prior therapy to Grade 0 or 1, except permitted residual toxicities.
• Life expectancy of at least 3 months.
• Able to swallow oral medication.
• Availability of tumor tissue and/or liquid biopsy suitable for next-generation sequencing.
• Willing to use highly effective contraception during study participation and for at least 3 months after the last dose of study treatment.
• Able and willing to provide written informed consent.

Exclusion criteria

• Systemic anticancer therapy or investigational therapy within 2 weeks or 5 half-lives prior to study treatment.
• Major surgery within 21 days before study treatment.
• Radiotherapy within 4 weeks for brain metastases or within 2 weeks for other disease sites.
• Significant uncontrolled cardiovascular, metabolic, psychiatric, or other serious medical conditions.
• QTcF >450 msec in males or >470 msec in females.
• History of optic neuritis or optic neuropathy.
• Active HIV infection or active hepatitis B or C infection.
• Active infection requiring systemic antibiotic therapy.
• Use of strong CYP3A inhibitors or inducers within protocol-specified washout periods.
• Gastrointestinal conditions that may significantly affect drug absorption.
• Pregnancy or breastfeeding.
• Participation in another interventional clinical study.
• Previous treatment with JBI-778.
• Any condition that, in the opinion of the investigator, would place the participant at unacceptable risk or interfere with study participation.