Open-Label Study of the CDK4/6 Inhibitor SPH4336 in Subjects With Locally Advanced or Metastatic Liposarcomas

A Phase 2 Multicenter, Open-Label Study of the CDK4/6 Inhibitor SPH4336 in Subjects With Locally Advanced or Metastatic Liposarcomas

Study SPH4336-US-01 is an open-label (no placebo), multicenter clinical trial to evaluate the safety, blood levels (pharmacokinetics) and preliminary anti-tumor effects of SPH4336, a selective enzyme blocker, in patients with specific types of liposarcomas (tumors expressing the target of the study drug).

Study Overview

• Status: Terminated
• Conditions: Liposarcoma, Dedifferentiated
• Intervention / Treatment: Drug: SPH4336

Detailed Description

Study SPH4336-US-01 is a multicenter, non-randomized, open-label Phase 2 study of SPH4336 with a safety lead-in in subjects with CDK4-positive liposarcomas (dedifferentiated or well-differentiated/dedifferentiated liposarcomas). SPH4336 is an orally administered, molecularly targeted chemotherapy drug called a cyclin-dependent kinase inhibitor (CDK4/6 inhibitor), which acts to block the ability of cancer cells to divide and thus prevents tumors from growing. SPH4336 (tablets) will be administered orally once each day in successive 28-day cycles until demonstration of progressive disease or the development of unacceptable toxicity.

The study will incorporate a safety lead-in for the initial 10 subjects. Safety will be evaluated after 10 subjects (minimum 1 cycle completed) by a Safety Review Committee (SRC). The study will be stopped if unacceptable toxicity is observed in more than 2 subjects.

Tumor assessments according to RECIST v1.1 will be performed at baseline and every 6 weeks (from Cycle 1, Day 1 (C1D1)) for 36 weeks, then every 12 weeks thereafter. Plasma samples for pharmacokinetics will be collected in all subjects. Baseline (pretreatment) tumor tissue (archival or fresh) will be collected from all subjects to confirm histologically a liposarcoma with a dedifferentiated component and CDK4 positivity. Tumor tissue biomarkers (e.g., phospho-Rb, Ki-67) will be analyzed in the first 10 study subjects in baseline (pretreatment) and C1D15 tumor tissue samples.

• Study Type: Interventional
• Enrollment (Actual): 14
• Phase: Phase 2

Contacts and Locations

Study Locations

• United States
  • Arizona
    • Phoenix, Arizona, United States, 85054
      • Mayo Clinic Hospital
  • California
    • Duarte, California, United States, 91010
      • City of Hope
  • Florida
    • Jacksonville, Florida, United States, 32224
      • Mayo Clinic Florida
    • Miami, Florida, United States, 33136
      • University of Miami
  • Michigan
    • Ann Arbor, Michigan, United States, 48109
      • University of Michigan
  • New Jersey
    • Hackensack, New Jersey, United States, 07601
      • Hackensack University Medical Center
  • Ohio
    • Cleveland, Ohio, United States, 44106
      • Seidman Cancer Center, University Hospitals
    • Columbus, Ohio, United States, 43210
      • The Ohio State University
  • Tennessee
    • Nashville, Tennessee, United States, 37232
      • Vanderbilt University Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 14 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Informed consent
• ≥ 18 years of age
• ECOG performance status 0 or 1

• Histologically confirmed, locally advanced or metastatic sarcoma

  • Dedifferentiated or well-differentiated/dedifferentiated liposarcomas
• No more than 3 prior lines of treatment

• Evidence of progression as evidenced by at least one of the following within the past 3 months:

  • An increase of at least 20% in measurable tumors
  • The appearance of new lesions
  • Unequivocal progression of non-measurable lesions
• Measurable disease per RECIST v1.1

• If residual treatment-related toxicity from prior therapy:

  • All treatment-related toxicity resolved to Grade 1 or baseline (alopecia excepted)
• ANC ≥ 1,500/μL
• Platelets ≥ 100,000/μL
• Hgb ≥ 9.0 g/dL (in the absence of pRBC transfusion over the prior 4 weeks)
• Estimated glomerular filtration rate of ≥ 60 mL/min (based on the Cockcroft and Gault formula for individualized estimates of GFR)
• Total bilirubin ≤ 1.5 x the Upper Limit of Normal (ULN) or ≤ 3 x ULN if known Gilbert's disease
• AST and ALT ≤ 3 x ULN or ≤ 5 x ULN if malignant involvement of the liver
• Sterile or willing to use effective contraception (approved hormonal contraceptive such as oral contraceptives, patches, implants, injections, rings or hormonally-impregnated intrauterine device (IUD), or an IUD in women of childbearing potential and a condom in men) during the study and for 3 months following the last dose of study drug
• Availability of archived tumor tissue or willingness to undergo a baseline tumor biopsy, and in the first 10 study subjects, to determine baseline tumor biomarker levels and a willingness to undergo a second tumor biopsy at C1D15 to assess treatment-induced changes in tumor biomarker levels

Exclusion Criteria:

• Prior treatment with a CDK4/6-targeted agent
• Patient's tumor known to be CDK4 negative
• Anticancer therapy (e.g., chemotherapy, biologics, irradiation) within 14 days or 5 half-lives (whichever is greater) of screening
• Major surgery within 28 days of screening
• Requirement for systemic treatment with strong CYP3A4 inhibitors or inducers of CYP3A4 at study entry
• Central nervous system metastases or leptomeningeal disease, unless appropriately treated and neurologically stable without steroids for ≥ 28 days
• Other malignancy unless disease-free for ≥ 2 years and not expected to relapse or require treatment during study participation
• Active systemic infection or severe localized infection
• Known HIV-positive with CD4+ cell counts < 350 cells/uL or a history of an AIDS-defining opportunistic infection
• Known hepatitis B virus (HBV) or hepatitis C virus (HCV) infection with viral load above the limit of quantification
• Active COVID-19 infection
• Major cardiac abnormalities (e.g., uncontrolled angina, unstable arrhythmias, myocardial infarction, NYHA Class ≥ 3 CHF) ≤ 6 months of C1D1
• Persistent (3 ECGs ≥ 5 mins apart) prolongation of the QTcF (Fridericia) > 470 msec
• [Females] Pregnant or nursing
• Any other medical or psychiatric condition, or laboratory abnormality that would result in an unacceptable risk with study participation
• Presence of active gastrointestinal disease or other condition expected to interfere significantly with absorption, distribution, metabolism or excretion of oral therapy (e.g., ulcerative disease, uncontrolled nausea, vomiting, chronic diarrhea, malabsorption syndrome)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: SPH4336; 400 mg (2 - 200 mg tablets) PO QD	Drug: SPH4336; 400 mg SPH4336 PO QD

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Progression-free Survival (PFS) at 12 Weeks	Number of total patients who are progression-free, as defined as RECIST v1.1 (a 20% increase in the sum of the longest diameter of target lesions, or a measurable increase in a non-target lesion, or the appearance of new lesions), at 12 weeks	12 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Median PFS	Time when 50% or more patients have progressed disease (per RECIST v1.1) or died	From date of randomization until the date of first documented progression or date of death from any cause, whichever came first, assessed up to 100 months
Best Overall Response	The best response (per RECIST v1.1) recorded from the start of the treatment until disease progression	From date of randomization until the date of first documented progression or date of death from any cause, whichever came first, assessed up to 100 months
Time to Response	Time from start of treatment to partial or complete response per RECIST v1.1	From date of randomization until the date of first documented progression or date of death from any cause, whichever came first, assessed up to 100 months
Duration of Response	Time from start of treatment to disease progression or death in patients who achieve complete or partial response per RECIST v1.1	From date of randomization until the date of first documented progression or date of death from any cause, whichever came first, assessed up to 100 months
Incidence and severity of adverse events	The incidence of each reported adverse event (regardless of its relationship to study drug) will be tabulated and classified using MedDRA and the severity of each adverse event will be graded by the Investigator using NCI CTCAE v5.0	From date of randomization until the date of first documented progression or date of death from any cause, whichever came first, assessed up to 100 months

Collaborators and Investigators

• Sponsor: Shanghai Pharma Biotherapeutics USA Inc.
• Investigators: Study Director: Kenneth W Locke, PhD, Shanghai Pharma Biotherapeutics USA Inc.

Study record dates

Study Major Dates

• Study Start (Actual): August 31, 2023
• Primary Completion (Actual): October 4, 2024
• Study Completion (Actual): October 31, 2024

Study Registration Dates

• First Submitted: October 11, 2022
• First Submitted That Met QC Criteria: October 13, 2022
• First Posted (Actual): October 14, 2022

Study Record Updates

• Last Update Posted (Actual): June 13, 2025
• Last Update Submitted That Met QC Criteria: June 10, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Keywords: CDK4/6 inhibitor
• Additional Relevant MeSH Terms: Neoplasms; Neoplasms by Histologic Type; Sarcoma; Neoplasms, Connective and Soft Tissue; Neoplasms, Adipose Tissue; Liposarcoma
• Other Study ID Numbers: SPH4336-US-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No