Clinical trial NCT04787042: Phase 1a and Phase 2 Study for Safety, Preliminary Efficacy, PK and PD of ST-067
Official title: A First-In-Human Phase 1/2 Open-Label Study of Intravenous ST-067, Subcutaneous ST-067 with or Without Obinutuzumab Pre-Treatment, and ST-067 in Combination with Pembrolizumab in Subjects with Advanced Solid Malignancies
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: PHASE1
PHASE2
Conditions: Cancer
Solid Tumor
Melanoma
Renal Cell Carcinoma
Triple-negative Breast Cancer
Non Small Cell Lung Cancer
Squamous Cell Carcinoma of the Head and Neck
Carcinoma
MSI-High
Lead sponsor: Simcha IL-18, Inc.
Sponsor class: INDUSTRY
Collaborators: name: Merck Sharp & Dohme LLC
First posted: 2021-03-08
Enrollment: 316
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NON_RANDOMIZED
Intervention model: SEQUENTIAL
Intervention model description: Dose escalation and expansion
Primary purpose: TREATMENT

Brief summary: This is a multiphase, multicenter study, which includes a Phase 1a open-label, dose escalation monotherapy study of ST-067 given as an SC injection with or without obinutuzumab \[Gazyva®\] pre-treatment, by IV infusion, and in combination with pembrolizumab. A Phase 2 monotherapy arm is also planned; the exact design of the Phase 2 study elements with respect to formulation and pre-treatment will be determined after completion of the Phase 1 study portion of the trial.

Detailed description: Phase 1a is designed to determine the maximum tolerated dose (MTD) and recommended Phase 2 dose (RP2D) of ST067, administered by subcutaneous (SC) or intravenous (IV) dosing, in subjects with relapsed or refractory solid tumors, as well as to determine the MTD and recommended Phase 2 dose of ST067, administered SC with obinutuzumab (Gazyva®) as pretreatment in subjects with relapsed or refractory solid tumors using a modified toxicity probability interval (mTPI) design. There will be evaluations of ST-067 PK and PD effects.

Phase 2 will evaluate the preliminary efficacy of ST-067 administered at the RP2D to patients with the following tumor types. A Simon 2 stage design is used to calculate the sample size and early stopping rules will be employed in the event of lack of efficacy in any of the cohorts. RECIST 1.1 will be used to assess tumor response every 8-12 weeks.

* Melanoma (n=28)
* Renal cell carcinoma (n=25)
* Triple-negative best cancer (n=25)
* Non-small cell lung cancer (n=25)
* squamous cell carcinoma of the head and neck (n=28)
* MSI-Hi tumors (n=25)

A Simon 2 stage design is used to calculate the sample size and early stopping rules will be employed in the event of lack of efficacy in any of the cohorts. RECIST 1.1 will be used to assess tumor response every 8-12 weeks.

Safety will be assessed for each patient throughout the study.

Eligibility criteria: Inclusion Criteria:

1. Male and female patients aged ≥18 years
2. Must provide written informed consent and any authorizations required by local law
3. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1
4. Have histologically or cytologically confirmed diagnosis of advanced/metastatic solid tumor

   For Phase 1a, the following solid tumors are allowed: Melanoma, Merkel cell, RCC, urothelial, NSCLC,TNBC, SCCHN, microsatellite instability high, high tumor mutation burden (Hi TMB) or mismatch repair deficient, gastric, cervical, endometrial, cutaneous squamous, small cell lung, esophageal, hepatocellular carcinoma and platinum resistant ovarian cancer.
   1. For patients who have developed disease progression through standard therapy, or
   2. For patients whom standard of care therapy that prolongs survival is unavailable or unsuitable (according to the investigator and after consultation with the Medical Monitor) For Phase 1 combination therapy dose escalation, the following solid tumors are allowed: Melanoma, Merkel cell, RCC, urothelial, NSCLC (with no EGFR, TRK receptor, or ALK positive mutations/fusions), TNBC, SCCHN, MSI-Hi tumors, Hi TMB or mismatch repair deficient, gastric, cervical, endometrial, cutaneous squamous, small cell lung, esophageal, and HCC

      * TNBC is diagnosed in a tumor which does not express estrogen receptor or progesterone receptor, is not human epidermal growth factor receptor 2 (HER2) 3+ on IHC or is negative by fluorescence in situ hybridization (FISH).
      * MSI high tumor should have mutations in 30% or more microsatellites by PCR or be negative for MSH1/2/6 or PMS-2 by IHC.
      * Hi-TMB high tumor has 10 mut/Mb or greater calculated from whole genome sequencing or whole exome sequencing

   For Phase 2, the following solid tumors are allowed:

   Melanoma, RCC, TNBC, NSCLC, SCCHN, and MSI-Hi tumors
5. Has at least 1 measurable lesion per RECIST 1.1 criteria which has not been biopsied or received prior irradiation
6. Has an accessible tumor for biopsy pre- and on-treatment (mandatory).

Exclusion Criteria:

1. History of another malignancy
2. Known symptomatic brain metastases requiring \>10 mg/day of prednisolone or equivalent
3. Significant cardiovascular disease (MI, thrombotic events,) within 6 months prior to study treatmentSignificant ECG abnormalities (Phase 1a and 2 monotherapy only) including unstable cardiac arrhythmia requiring medication, second-degree atrioventricular block type II, third degree AV
4. Any degree of respiratory compromise (from either malignant or non-malignant disease)
5. Evidence of an ongoing systemic bacterial, fungal, or viral infection
6. Has received a live vaccine within 30 days
7. Major surgery within 4 weeks
8. Prior solid organ or bone marrow progenitor cell transplantation
9. Prior high dose chemotherapy requiring stem cell rescue
10. History of active autoimmune disorders
11. Ongoing immunosuppressive therapy, including systemic or enteric corticosteroids.
12. Treatment with an approved, systemic anticancer therapy or an investigational agent within 4 weeks of Day 1
13. A positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral test within 28 days prior to dosing, unless there is Investigator-confirmed clinical recovery on or before C1D1
14. Subjects with adrenal insufficiency
15. Subjects with any chemistry or hematology laboratory values that are ≥Grade 2

    Additional exclusion criteria for Phase 1 combination therapy only:
16. Presence of known active CNS metastases and/or carcinomatous meningitis. Subjects with previously treated brain metastases may participate provided they are radiologically stable, i.e., without evidence of progression for at least 4 weeks by repeat imaging, clinically stable, and without requirement of steroid treatment for at least 14 days prior to first dose of study treatment.
17. Prior radiotherapy within 2 weeks of start of study treatment or history of radiation pneumonitis.
18. Presence of an active documented autoimmune disease that has required systemic treatment in the past 2 years (i.e., with use of disease modifying agents, corticosteroids, or immunosuppressive drugs). Replacement therapy (e.g., thyroxine or insulin) is not considered a form of systemic treatment and is allowed. Subjects may use topical and/or inhaled corticosteroids. However, subjects with adrenal insufficiency on replacement doses of steroids are not allowed.
19. Prior therapy with an anti-PD-1, anti-PD-L1, or anti-PD-L2 agent or with an agent directed to another stimulatory or co-inhibitory T-cell receptor (e.g., CTLA-4, OX40, CD137), and was discontinued from that treatment due to a Grade 3 or higher irAE
20. Severe hypersensitivity (≥Grade 3) to pembrolizumab and/or any of its excipients. Subjects who have been retreated after such a reaction may be allowed after discussion with the Simcha Medical Monitor
21. History of (non-infectious) pneumonitis/interstitial lung disease that required steroids or has current pneumonitis/interstitial lung disease
22. Subjects that have received radiation therapy to the lung that is \>30Gy within 6 months of the first dose of study treatment

Primary outcomes:
measure: Determine the maximum tolerated dose of ST-067 in phase 1a monotherapy
timeFrame: Day 29
measure: Evaluate the overall safety and tolerability of ST-067 in combination with pembrolizumab
timeFrame: Day 29
measure: Number of Participants With Treatment-Related Adverse Events
timeFrame: Day 29
measure: Initial assessment of efficacy in phase 2
timeFrame: At 8 weeks
Secondary outcomes:
measure: PK
timeFrame: Day 29
measure: ADA
timeFrame: Day 29
Other outcomes:
Locations:
city: Scottsdale
country: United States
facility: HonorHealth Research Institute
state: Arizona
city: Denver
country: United States
facility: Sarah Cannon Research Institute at HealthONE
state: Colorado
city: New Haven
country: United States
facility: Yale Cancer Center
state: Connecticut
city: Tampa
country: United States
facility: Moffitt Cancer Center
state: Florida
city: Boston
country: United States
facility: Massachusetts General Hospital
state: Massachusetts
city: Buffalo
country: United States
facility: Roswell Park Cancer Institute
state: New York
Study officials:
affiliation: Simcha IL-18, Inc.
name: Jeremy Barton, MD
role: STUDY_DIRECTOR
References: