Testing the Safety and Tolerability of CX-4945 in Patients With Recurrent Medulloblastoma Who May or May Not Have Surgery
![]() |
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. |
ClinicalTrials.gov Identifier: NCT03904862 |
Recruitment Status :
Recruiting
First Posted : April 5, 2019
Last Update Posted : April 28, 2023
|
- Study Details
- Tabular View
- No Results Posted
- Disclaimer
- How to Read a Study Record
Condition or disease | Intervention/treatment | Phase |
---|---|---|
Medulloblastoma, Childhood | Drug: CX 4945 | Phase 1 Phase 2 |
PRIMARY OBJECTIVES:
I. To estimate the maximum tolerated dose (MTD) and/or the recommended phase II dose (RP2D) of CX-4945 administered orally daily to skeletally-immature children with recurrent SHH (sonic hedgehog) medulloblastoma (Phase I) II. To describe the toxicity profile and define the dose-limiting toxicities (DLTs) of CX-4945 in skeletally-immature children with recurrent SHH (sonic hedgehog) medulloblastoma. (Phase I) III. To characterize the pharmacokinetics of CX-4945 administered orally daily to skeletally-immature children with recurrent SHH (sonic hedgehog) medulloblastoma. (Phase I) IV. To characterize the concentrations of CX-4945 in tumor after administration of CX-4945 and surgical resection (Surgical Study). V. To establish the safety and characterize the toxicity of 1000mg BID continuous dosing of CX-4945 in skeletally-mature patients with recurrent SHH medulloblastoma (Phase II). VI. To estimate the objective response rate associated with CX-4945 in skeletally-mature patients with recurrent SHH medulloblastoma
SECONDARY OBJECTIVES:
I. To document preliminary antitumor activity of CX-4945 in skeletally-immature children with recurrent SHH medulloblastoma (Phase I). II. To perform a genomic analysis within the confines of a Phase I study to investigate correlation between response to treatment and the presence of specific genomic alterations. and/or specific subgroups of disease (Phase I). III. To explore the ability of CX-4945 at the MTD/ RP2D to inhibit CK2-mediated signaling in tumor (Surgical Study). IV. To characterize the pharmacokinetics of CX-4945 in skeletally-mature patients with recurrent SHH medulloblastoma (Phase II). V. To perform a genomic analysis within the confines of a Phase II study to investigate correlation between response to treatment and the presence of specific genomic alterations and/or specific subgroups of disease (Phase II).
OUTLINE: Phase I component is a dose-escalation study. The Phase II component is to establish the safety of 1000mg BID given continuously.
The study will open with a safety cohort of 3 subjects who are considered skeletally-mature. The initial 3 subjects will be administered CX-4945 twice a day at the adult RP2D of 1000 mg BID or at its BSA adjusted equivalent; however, the dose will be given continuously. If there are not excessive toxicities in this cohort, the study will proceed following the Phase II design for subjects who are skeletally-mature.
Following the safety lead in, the Phase 1 component of this trial will be initiated. Skeletally-immature children with refractory or recurrent medulloblastoma of the SHH subgroup, will be administered CX-4945 twice a day on a continuous basis at a starting dose of 600mg/m2 BID which corresponds approximately to the BSA adjusted recommended Phase 2 dose (RP2D) of 1000mg. The Phase 1 study will escalate doses to determine the maximum tolerated dose skeletally-immature children.
The surgical study will be initiated after the first 3 patients in the skeletally-mature cohort are treated for initial assessment of safety and did not experience excessive toxicity. Skeletally-mature subjects with recurrent or refractory SHH medulloblastoma will be eligible as soon the surgical study is initiated and will receive drug at 1000mg BID or its BSA adjusted equivalent depending upon age and BSA. Skeletally-immature subjects will only be eligible to enroll on the surgical trial once the MTD is defined in the Phase 1 component and will receive drug at the established MTD for this cohort.
After completion of study treatment, patients are followed up to 2 years.
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 60 participants |
Allocation: | Non-Randomized |
Intervention Model: | Parallel Assignment |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | PBTC-053: A Pediatric Brain Tumor Consortium Phase I/ II and Surgical Study of CX-4945 in Patients With Recurrent SHH Medulloblastoma |
Actual Study Start Date : | July 25, 2019 |
Estimated Primary Completion Date : | September 7, 2028 |
Estimated Study Completion Date : | November 6, 2028 |

Arm | Intervention/treatment |
---|---|
Experimental: Phase I - Skeletally-immature
Skeletally-immature children with refractory or recurrent medulloblastoma of the SHH group
|
Drug: CX 4945
CX-4945 is supplied as 200 mg capsules delivered orally as a formulated API
Other Name: Silmitasertib sodium |
Experimental: Phase II - Skeletally-mature
Skeletally-mature subjects with refractory or recurrent medulloblastoma of the SHH group
|
Drug: CX 4945
CX-4945 is supplied as 200 mg capsules delivered orally as a formulated API
Other Name: Silmitasertib sodium |
Experimental: Surgical
Subjects who are eligible for the Phase I or Phase II arm of the trial and are candidates for surgery, may be enrolled in the surgical arm prior to initiation of the Phase I or Phase II treatment.
|
Drug: CX 4945
CX-4945 is supplied as 200 mg capsules delivered orally as a formulated API
Other Name: Silmitasertib sodium |
- Phase I: Maximum tolerated dose of CX-4945 [ Time Frame: 4 weeks ]Defined as the highest dose level at which six patients have been treated with at most one patient experiencing a dose limiting toxicity (DLT) and the next higher dose level has been determined to be too toxic.
- Phase I: Plasma pharmacokinetics of CX-4945 in skeletally-immature children [ Time Frame: 4 weeks ]To report the plasma drug concentration of CX-4945 on this schedule in skeletally-immature children
- Surgical Study: Intratumoral PK concentrations [ Time Frame: Prior to starting CX-4945 (Day -5 or -7), prior to dose on Day -3, prior to dose on Day -1, day of surgery and during surgery at the time of tissue collection ]Average tumor CX-4945 concentrations.
- Phase II: Sustained objective response rate (PR-CR) rate in the skeletally mature cohort [ Time Frame: Up to 2 years from enrollment ]Percentage of patients who achieve sustained objective response.
- Progression free survival [ Time Frame: Up to 3 years from enrollment ]Interval of time between the date of initiation of protocol treatment and minimum date of documentation of PD, second malignancy, death due to any cause or date of last follow-up.
- Objective response rate in the skeletally-immature cohort [ Time Frame: Up to 2 years from enrollment ]Percentage of patients who achieve objective response in the skeletally-immature cohort
- Plasma pharmacokinetics of CX-4945 in skeletally-mature subjects [ Time Frame: 4 weeks ]To report the plasma drug concentration of CX-4945 in skeletally-mature subjects
- Relative frequency of genomic alterations in archival tissue [ Time Frame: At time of enrollment ]Percentage of various genomic alterations will be reported
- Surgical study: Reduction in CK2-mediated signaling in tumor. [ Time Frame: 4 weeks ]Change in CK2 activity in tumor tissue from patients on the surgical are at baseline and after treatment.

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 3 Years and older (Child, Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
A. Screening Criteria:
Subject must have a diagnosis of medulloblastoma that is recurrent or refractory and must have adequate tissue for SHH subgrouping.
B. Inclusion Criteria:
-
Phase I Skeletally-immature:
a. Patient must be skeletally-immature at the time of study enrollment, defined as females with a bone age < 14 years and males with a bone age < 16 years. Patient must be ≥3 and ≤18 years of age and BSA must meet protocol restrictions.
-
Phase II Skeletally-mature:
- Patients must be skeletally-mature, defined as females with a bone age ≥14 years and males with a bone age ≥ 16 years OR have a chronological age >18 years.
- Must have bi-dimensionally measurable disease
-
Surgical Study:
- Surgical resection must be clinically indicated.
- Must be ≥3 years.
- Must be amenable to receiving CX-4945 for 5-7 days prior to surgery
-
All Phases:
- Must have a diagnosis of SHH medulloblastoma that is recurrent or progressive which was confirmed histologically and subgrouping was completed using a CLIA certified methylation based test.
-
Prior Therapy
- Must have received prior therapy which included radiation therapy and recovered from acute treatment related toxicities.
- Must have received the last dose of myelosuppressive therapy at least 21 days prior to enrollment and at least 42 days if nitrosourea.
- Must have received the last dose of another investigational or biologic agent ≥7 days prior. For agents known to have adverse events occurring beyond 7 days, the period must be extended to accommodate the longer interval. For monoclonal antibodies with prolonged half-lives, at least 3 half-lives must have elapsed.
- Must have received last fraction of craniospinal or total body irradiation or radiation to ≥50% of the pelvis >3 months prior to enrollment. Last fraction of focal irradiation must be >4 weeks prior to enrollment.
- Must be ≥ 6 months since allogeneic stem cell transplant with no evidence of acute graft vs. host disease.
- Must be ≥3 months since autologous stem cell transplant.
- Must be off all colony-forming growth factors at least 1 week prior to enrollment. Must be off 2 weeks if the subject received a long-acting formulation.
-
If neurological deficits are present, must have been stable for a minimum of 1 week prior to enrollment.
• Patients with seizure disorders may be enrolled if seizures are well controlled.
- Must have a Karnofsky/Lansky Performance status ≥50%
- Must have adequate organ and marrow function
- Subjects receiving dexamethasone must be on a stable or decreasing dose for at least 1 week prior to enrollment.
- Female patients of childbearing potential must have a negative pregnancy test.
- Patients of child-bearing or child fathering potential must be willing to use medically acceptable form of birth control while treated on this study and for 3 months after drug cessation.
- Parent or legal guardian must be able to understand and willing to sign the written informed consent.
C. Exclusion Criteria:
1. All Phases
- Nursing mothers due to an unknown but potential risk for adverse events in nursing infants.
- Patients with a history of any other malignancy with the exception of patients with a secondary brain tumor if the patient's prior malignancy has been in remission for at least 5 years from the end of treatment.
- Patients with any of the following gastrointestinal disorders - difficulty swallowing or active malabsorption, uncontrolled diarrhea, gastritis, ulcerative colitis, Crohn's disease or hemorrhagic coloproctitis, history of gastric or small bowel surgery involving any extent of gastric or small bowel resection.
- Patients with any clinically significant unrelated systemic illness that would compromise the patient's ability to tolerate therapy, put them at additional risk for toxicity or interfere with the study procedures or results.
- Corrected QT (QTc) interval is >480ms
- Patients who are receiving other anti-cancer or investigational drug therapy
- Patients who are on warfarin or statins.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03904862
Contact: Vanetria Stokes, MS | 901-595-5762 | vanetria.stokes@stjude.org | |
Contact: Nina Butingan, MBS | 901-671-6767 | nina.butingan@stjude.org |
United States, California | |
Children's Hospital of Los Angeles | Recruiting |
Los Angeles, California, United States, 90026 | |
Contact: Nathan Robison, MD 323-361-8147 nrobison@chla.usc.edu | |
Contact: Ashley Margol, MD 323-361-8464 amargol@chla.usc.edu | |
Stanford University and Lucile Packard Children's Hospital | Recruiting |
Palo Alto, California, United States, 94304 | |
Contact: Sonia Partap, MD 650-723-7299 spartap@stanford.edu | |
United States, District of Columbia | |
Children's National Medical Center | Recruiting |
Washington, District of Columbia, United States, 20010 | |
Contact: Gene Hwang, MD 202-476-3472 EHwang@childrensnational.org | |
Contact: Lindsay Kilburn, MD 202-476-2800 LKilburn@childrensnational.org | |
United States, Florida | |
University of Florida | Recruiting |
Gainesville, Florida, United States, 32608 | |
Contact: Elias Sayour, MD, PhD 352-294-5272 elias.sayour@neurosurgery.ufl.edu | |
United States, Georgia | |
Children's Healthcare of Atlanta | Recruiting |
Atlanta, Georgia, United States, 30322 | |
Contact: Jason Fangusaro, MD 404-785-6011 jason.ronald.fangusaro@emory.edu | |
Contact: Tobey MacDonald, MD 404-785-6011 tobey.macdonald@emory.edu | |
United States, Illinois | |
Ann & Robert H. Lurie Children's Hospital of Chicago | Recruiting |
Chicago, Illinois, United States, 60611 | |
Contact: Alicia Lenzen, MD 312-227-4874 alenzen@luriechildrens.org | |
United States, New York | |
Memorial Sloan-Kettering Cancer Center | Recruiting |
New York, New York, United States, 10065 | |
Contact: Ira Dunkel, MD 212-639-2153 dunkeli@mskcc.org | |
United States, Ohio | |
Cincinnati Children's Hospital Medical Center | Recruiting |
Cincinnati, Ohio, United States, 45229 | |
Contact: Natasha Pillay Smiley, DO 513-636-0673 natasha.pillay-smiley@cchmc.org | |
Nationwide Children's Hospital | Recruiting |
Columbus, Ohio, United States, 43205 | |
Contact: Ralph Salloum, MD 612-722-2490 ralph.salloum@nationwidechildrens.org | |
United States, Pennsylvania | |
Children's Hospital of Pittsburgh of UPMC | Recruiting |
Pittsburgh, Pennsylvania, United States, 15201 | |
Contact: Alberto Broniscer, MD 412-692-5056 alberto.broniscer@chp.edu | |
Contact: Ian Pollack, MD 412-692-5881 ian.pollack@chp.edu | |
United States, Tennessee | |
St. Jude Children Research Hospital | Recruiting |
Memphis, Tennessee, United States, 38105 | |
Contact: Giles Robinson, MD 901-595-2907 giles.robinson@stjude.org | |
Sub-Investigator: Amar Gajjar, MD | |
United States, Texas | |
Baylor College of Medicine | Recruiting |
Houston, Texas, United States, 77030 | |
Contact: Patricia Baxter, MD 832-824-4681 pabaxter@txch.org | |
Contact: Susan Burlingame, CCRP 832-824-1532 sxburlin@txch.org | |
Principal Investigator: Patricia Baxter, MD |
Principal Investigator: | Ralph Salloum, MD | Children's Hospital Medical Center, Cincinnati |
Responsible Party: | Pediatric Brain Tumor Consortium |
ClinicalTrials.gov Identifier: | NCT03904862 |
Other Study ID Numbers: |
PBTC-053 5UM1CA081457 ( U.S. NIH Grant/Contract ) |
First Posted: | April 5, 2019 Key Record Dates |
Last Update Posted: | April 28, 2023 |
Last Verified: | April 2023 |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Medulloblastoma Sonic Hedgehog (SHH) positive |
Medulloblastoma Glioma Neoplasms, Neuroepithelial Neuroectodermal Tumors Neoplasms, Germ Cell and Embryonal |
Neoplasms by Histologic Type Neoplasms Neuroectodermal Tumors, Primitive Neoplasms, Glandular and Epithelial Neoplasms, Nerve Tissue |