Purpose

RBS2418 is a targeted immune modulator that inhibits ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1). It is designed to promote anti-tumor immunity by preserving endogenous 2'-3' cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) from hydrolysis, thereby activating antigen-presenting cells and promoting robust T cell activation. Ideally, RBS2418 acts synergistically with CTLA-4 inhibitors, such as those in the STRIDE regimen (Tremelimumab plus Durvalumab). The hypothesis is that RBS2418 combined with STRIDE will be safe, well-tolerated, highly immunogenic, and enhance anti-tumor responses in adult participants with advanced, unresectable hepatocellular carcinoma (HCC) compared to STRIDE alone.

Condition

Eligibility

Eligible Ages
Over 18 Years
Eligible Sex
All
Accepts Healthy Volunteers
No

Inclusion Criteria

  1. At least 18 years of age on the day of signing informed consent. 2. Male and female participants with advanced, unresectable HCC who are eligible to receive STRIDE regimen as first line therapy. 3. Willing to submit a pre-treatment tissue sample (archival or fresh tissue if archival is not available).

Exclusion Criteria

  1. BCLC stage D disease at the time of screening or prior to first dose of RBS2418. 2. Child-Pugh class equal or higher than B8 at the time of screening or within 7 days prior to the first dose of study treatment. 3. Eligible for curative treatments (e.g., surgical resection, liver transplantation, or local ablation). 4. Evidence of rapid progression on prior therapy resulting in rapid clinical deterioration.

Study Design

Phase
Phase 2
Study Type
Interventional
Allocation
Randomized
Intervention Model
Parallel Assignment
Primary Purpose
Treatment
Masking
None (Open Label)

Arm Groups

ArmDescriptionAssigned Intervention
Active Comparator
Arm A: RBS2418, 200mg BID, plus STRIDE
RBS2418 200 mg PO, BID in combination with STRIDE regimen
  • Drug: RBS2418
    RBS2418 is a specific immune modulator that works through the inhibition of ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) and is designed to lead to anti-tumor immunity by protecting endogenous 2'-3'-cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) from hydrolysis and leading to the activation of antigen-presenting cells followed by T cell activation.
  • Drug: STRIDE (durvalumab + tremelimumab)
    STRIDE: Tremelimumab 300 mg IV (Cycle 1 Day 1 only) Plus Durvalumab 1500 mg IV every 4 weeks
Active Comparator
Arm B: RBS2418, 800mg BID, plus STRIDE
RBS2418 800 mg PO, BID in combination with STRIDE regimen
  • Drug: RBS2418
    RBS2418 is a specific immune modulator that works through the inhibition of ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) and is designed to lead to anti-tumor immunity by protecting endogenous 2'-3'-cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) from hydrolysis and leading to the activation of antigen-presenting cells followed by T cell activation.
  • Drug: STRIDE (durvalumab + tremelimumab)
    STRIDE: Tremelimumab 300 mg IV (Cycle 1 Day 1 only) Plus Durvalumab 1500 mg IV every 4 weeks
Active Comparator
Arm C: STRIDE alone (control)
STRIDE regimen
  • Drug: STRIDE (durvalumab + tremelimumab)
    STRIDE: Tremelimumab 300 mg IV (Cycle 1 Day 1 only) Plus Durvalumab 1500 mg IV every 4 weeks

Recruiting Locations

Vanderbilt-Ingram Cancer Center
Nashville, Tennessee 37232

More Details

Status
Recruiting
Sponsor
Riboscience, LLC.

Study Contact

Riboscience Clinical Trials
415-754-3182
clinicaltrials@riboscience.com

Detailed Description

In this Phase 2a study, participants must have advanced, unresectable HCC confirmed by radiology, histology or cytology. Participants must be eligible to receive the STRIDE regimen as first line therapy. Participants must have measurable disease per RECIST 1.1, an Eastern Cooperative Oncology Group (ECOG) performance score of 0, 1 or 2, and predicted life expectancy of at least 12 weeks. Up to approximately 220 participants will be enrolled and will receive therapy as part of their respective treatment group. Participants will receive study treatment of RBS2418 at two different dose levels (200mg and 800mg) twice daily in combination with STRIDE or STRIDE alone with a treatment period consisting of 28-day cycles up to two years or until there is progressive disease, death, withdrawal, or study completion, whichever comes first. Adverse Events (AEs) will be monitored throughout the study and graded in severity according to the guidelines outlined in the NCI CTCAE v5.0. AEs will be collected until up to 30 days after the last dose of RBS2418 or until resolution, whichever comes first. SAEs will be collected for 90 days after the last dose of RBS2418, or if the participant initiates new anti-cancer therapy, then 30 days after the RBS2418 last dose, whichever is earlier.

Notice

Study information shown on this site is derived from ClinicalTrials.gov (a public registry operated by the National Institutes of Health). The listing of studies provided is not certain to be all studies for which you might be eligible. Furthermore, study eligibility requirements can be difficult to understand and may change over time, so it is wise to speak with your medical care provider and individual research study teams when making decisions related to participation.