Clinical trial Recruiting at 3 sites Phase1; Phase2 Interventional Ages 18 and up

Evaluating the safety and effectiveness of SA53-OS in patients with advanced solid tumors

Official title: A Phase 1/2a, Open-Label Study of Safety, Tolerability, Pharmacokinetics, and Preliminary Efficacy of SA53-OS, an MDM2 Inhibitor, in Patients With Locally Advanced or Metastatic p53 Wild-Type Solid Tumors

Run by Lamassu Bio Inc · NCT06578624 · Data updated 2026-11-12

This study is testing a new oral medication called SA53-OS to see if it can safely help adults with advanced solid tumors, especially those with dedifferentiated liposarcoma, by promoting tumor cell death.

More Solid Tumor trials

Quick facts

PhasePhase1; Phase2
Study typeInterventional
Ages18 Years and up
SexAll
Enrollment55 (estimated)
SponsorLamassu Bio Inc
Industry-sponsored
Drugs / interventionsradiation
Locations3 sites (Canton, Ohio and 2 other locations)
StatusRecruiting
StartedJune 16, 2025
Main results expectedJuly 1, 2031
Study endsAugust 1, 2031
Registry record updatedNovember 9, 2026
Trial IDNCT06578624 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Ideal candidates include adults aged 18 and older with p53 wild-type refractory solid tumors, particularly those with dedifferentiated liposarcoma or other solid tumors.

Probably not a fit

Patients with primary central nervous system malignancies or those who have not experienced prior systemic therapy may not benefit from this study.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This clinical trial aims to assess the safety, efficacy, and pharmacokinetics of a novel MDM2 inhibitor, SA53-OS, in adult patients with refractory solid tumors. The study is divided into two parts: a dose escalation phase to determine the maximum tolerated dose (MTD) and a dose expansion phase focusing on patients with dedifferentiated liposarcoma (DD LPS) and other solid tumors. Participants will receive SA53-OS as an oral solution for three consecutive days every three weeks, potentially for up to two years. The trial will evaluate the drug's ability to activate the p53 tumor suppressor protein, facilitating tumor cell death and growth inhibition.

Why it matters

Potential benefit: If successful, this treatment could provide a new therapeutic option for patients with advanced solid tumors that currently have limited effective treatments.

How similar studies have gone: While this approach is novel, similar studies targeting MDM2 inhibition have shown promise in early phases.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Tumor characteristics of participants in Phase 1

  1. Histologically and/or cytologically confirmed diagnosis of advanced or metastatic solid tumor and/or non-Hodgkin lymphoma excluding primary central nervous system malignancy for which no standard effective treatment exists or where that treatment was declined. Participants with non-Hodgkin lymphoma should have failed ≥ 2 prior lines of systemic therapy prior enrollment.
  2. Tumor p53 wild-type.
* Tumor characteristics of participants in Phase 2a

  1. Cohort A: Tumor p53 wild-type with histologically confirmed diagnosis of advanced or metastatic DD LPS (and MDM2 amplification); OR Cohort B: Tumor p53 wild-type in other solid tumor.
  2. Measurable disease by RECIST 1.1.
* 18 years old or older.
* Resolution of clinically relevant toxicity-related to prior anticancer therapies prior to receipt of study treatment to Grade 1 or less.
* Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.
* Participants of childbearing/reproductive potential must agree to use adequate birth control measures during the course of the trial and for at least 3 months after discontinuing study treatment.

Exclusion Criteria:

* Anticipated need for major surgery and/or localized palliative radiation within the next 6 weeks
* Active, untreated central nervous system metastases. Participants with brain metastases identified at Screening may be rescreened after the lesion(s) have been appropriately treated; participants with treated brain metastases should be neurologically stable for 4 weeks post-treatment and prior to study enrollment, and off corticosteroids for at least 2 weeks before start of study treatment, and treated lesions should demonstrate no new growth on the re-screening scan.
* Known HIV infection or active hepatitis B or C infection.
* Thrombotic event requiring active and ongoing anticoagulation within the last 6 months prior to study treatment.
* Myocardial infarction within the last 6 months prior to study treatment.
* Significant cardiovascular disease including unstable angina pectoris, uncontrolled hypertension or arrhythmia, congestive heart failure New York Heart Association (NYHA) Class III or IV related to primary cardiac disease, uncontrolled ischemic or severe vascular heart disease.
* A history of additional risk factors for Torsades de Pointes (TdP) (e.g., heart failure, hypokalemia, family history of Long QT Syndrome)
* Known bleeding disorder (e.g., hemophilia, von Willebrand disease).
* Conditions that may predispose to major bleeding (e.g., active GI ulcers, upper or lower GI bleedings in the last 6 months, significant hemoptysis in the last 6 months, tumor invasion of major vessels, etc.). Conditions that have been treated may be allowed if resolution of the risk is documented.
* Use or indication for full dose anticoagulation or anti-platelet therapy including low dose aspirin.
* Women who are pregnant or lactating.

Where it's running

  • Gabrail Cancer Center
    Canton, Ohio, United States
    Recruiting
  • University Hospitals Cleveland Medical Center
    Cleveland, Ohio, United States
    Recruiting
  • Cleveland Clinic Taussig Cancer Institute
    Cleveland, Ohio, United States
    Recruiting

Study contacts

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.