Recruiting
Phase 1
Phase 2

PEEL-224, Vincristine, Temozolomide

Sponsor:

David S Shulman, MD

Code:

NCT06709495

Conditions

Sarcoma

Sarcoma, Ewing

Desmoplastic Small Round Cell Tumor

Refractory Sarcoma

Osteosarcoma

Eligibility Criteria

Sex: All

Age: 12 - 49

Healthy Volunteers: Not accepted

Interventions

PEEL-224

Temozolomide

Vincristine

Pegfilgrastim

Filgrastim

Study Details

Brief summary:

This research is being done to test a new drug called PEEL-224 in combination with two commercially available drugs, Vincristine and Temozolomide, and to determine how effective this combination of drugs is at treating Ewing Sarcoma (EWS) and Desmoplastic Small Round Cell Tumor (DSRCT), as well as multiple other kinds of sarcomas.

The names of the study drugs and biological agents involved in this study are:

  • PEEL-224 (a type of Topoisomerase 1 inhibitor)
  • Vincristine (A type of vinca alkaloid)
  • Temozolomide (A type of alkylating agent)
  • Pegfilgrastim or Filgrastim (types of Myeloid growth factors)

Conditions

Sarcoma

Sarcoma, Ewing

Desmoplastic Small Round Cell Tumor

Refractory Sarcoma

Osteosarcoma

Study ID

NCT06709495

Start date

Jan 27, 2025

Status verified date

Feb, 2026

Completion date

Sep 1, 2029

Anticipated

Primary completion date

Nov 1, 2028

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 12 - 49

Healthy Volunteers: Not accepted

Inclusion Criteria:

-Patients in all cohorts must have relapsed or refractory disease after standard therapy.

Inclusion Criteria Phase 1 (only) diagnosis requirements:

-Patients must have:

  • Evaluable or measurable disease; and
  • Histologic diagnosis of sarcoma

Inclusion Criteria Phase 2 (only) diagnosis requirements

  • EWS cohort: Patients must have:

  • RECIST measurable disease at study entry;
  • Histologic diagnosis consistent with Ewing sarcoma; and
  • Molecular evidence of a FET-ETS family translocation including but not limited to any of the following:

  • EWSR1::FLI1, EWSR1::ERG, EWSR1::ETV1, EWSR1::ETV4, EWSR1::FEV, FUS::FLI1, FUS::ERG
  • DSRCT cohort: Patients must have:

  • RECIST measurable disease at study entry;
  • Histologic diagnosis consistent with DSRCT; and
  • Molecular evidence of an EWSR1::WT1 fusion
  • Other sarcoma cohort: Patients must have:

  • RECIST evaluable or measurable disease; and
  • Histologic diagnosis of sarcoma. Patients with EWS or DSRCT with evaluable but not measurable disease may participate in this cohort.
  • Slots in this cohort will include three dedicated slots for patients with rhabdomyosarcoma, three dedicated slots for patients with osteosarcoma and three dedicated slots for patients with other translocation-associated round cell sarcomas.
  • Age: ≥ 12 years and ≤ 49 years.
  • Weight: Patients must be ≥ 40 kg.
  • Performance Status: Karnofsky ≥ 50% for patients >16 year of age and Lansky ≥ 50% for patients ≤ 16 years of age. (see Appendix A for definitions of Lansky and Karnofsky Performance Status).
  • Participants must meet the following organ and marrow function as defined below: Adequate Bone Marrow Function:

  • Hematologic Requirements for Subjects without Bone Marrow Involvement by

Disease:

  • Absolute neutrophil count (ANC) ≥ 1,000/uL
  • Platelet count ≥100,000/uL (transfusion independent, defined as not receiving platelet transfusions for at least 7 days prior to enrollment)

--Hematologic Requirements for Subjects with Bone Marrow Involvement by Disease:
  • ANC ≥750 /uL
  • Platelets ≥50,000 /uL (may receive platelet transfusions) Not known to be refractory to red cell and/or platelet transfusions.

--Adequate Renal Function: Creatinine clearance or radioisotope GFR ≥70ml/min/1.73 m2 or A serum creatinine based on age/sex as follows:
  • Age: 12 to < 13 years, Maximum Serum Creatinine (mg/dL): Male 1.2, Female 1.2
  • Age 13 to < 16 years, Maximum Serum Creatinine (mg/dL): Male 1.5, Female 1.4

---≥ 16 years, Maximum Serum Creatinine (mg/dL): Male 1.7, Female 1.4

--Adequate Liver Function:
  • Bilirubin (sum of conjugated + unconjugated) ≤ 1.5 x upper limit of normal (ULN) for age
  • SGPT (ALT) ≤110 U/L. For the purpose of this study, the ULN for SGPT is 45 U/L.

  • Adequate Cardiac Function: QTc < 480 msec

-Patients must have fully recovered from the acute toxic effects of all prior anti-cancer therapy except organ function as noted above. Patients must meet the following minimum washout periods prior to enrollment:
  • Myelosuppressive chemotherapy: At least 14 days after the last dose of myelosuppressive chemotherapy
  • Radiotherapy:
  • At least 14 days after local XRT (small port, including cranial radiation);
  • At least 90 days must have elapsed after prior TBI, craniospinal XRT or if >50% radiation of pelvis;
  • At least 42 days must have elapsed if other substantial BM radiation.

  • Small molecule biologic therapy: At least 7 days following the last dose of a biologic agent.
  • Monoclonal antibody: At least 21 days must have elapsed after the last dose of antibody.
  • Myeloid and platelet growth factors: At least 14 days following the last dose of long-acting myeloid growth factor (e.g. Neulasta) or 7 days following short-acting myeloid or platelet growth factor.
  • Autologous hematopoietic stem cell transplant and stem cell boost: Patients must be at least 60 days from day 0 of an autologous stem cell transplant or stem cell boost.
  • Cellular Therapies (e.g., CART, NK-cell based therapy): The patient must be and at least 42 days from cellular therapy administration.
  • Major Surgery: At least 2 weeks from prior major surgical procedure. Note: Biopsy, CNS shunt placement/revision, and central line placement/removal are not considered major.
  • Irinotecan, liposomal irinotecan, and/or temozolomide: Patients may have received prior irinotecan, liposomal irinotecan, and/or temozolomide. NOTE: Patients who have had progressive disease while receiving irinotecan and temozolomide in combination will be excluded from the Phase 2 EWS and DSRCT cohorts only.

-For patients with metastatic disease to the CNS enrolling to the phase 1 portion of the trial or the "other sarcoma" cohort, any baseline neurologic deficits (including seizure) must be stable for at least one week prior to study enrollment. Patients with CNS metastatic disease receiving corticosteroids must be on a stable or decreasing dose at time of study entry.
  • Patients with CNS metastatic disease will not be eligible for the phase 2 EWS and DSRCT cohorts.

  • Participants with a prior or concurrent malignancy whose natural history or treatment does not have the potential to interfere with the safety or efficacy assessment of the investigational regimen are eligible for this trial.
  • The effects of PEEL-224 in combination with temozolomide and vincristine on the developing human fetus are unknown. For this reason, women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry and for the duration of study participation. Should a woman become pregnant or suspect she is pregnant while she or her partner is participating in this study, she should inform her treating physician immediately. Men treated or enrolled on this protocol must also agree to use adequate contraception prior to the study, for the duration of study participation, and 4 months after completion of PEEL-224 administration.
  • Ability to understand and/or the willingness of the patient (or parent or legally authorized representative, if minor) to provide informed consent, using an institutionally approved informed consent procedure.
  • Any participant must obtain prior approval from insurance to reimburse oral temozolomide for the duration of the study or agree to self-pay for oral temozolomide.

Exclusion Criteria:

  • Patients who have received prior treatment with PEEL-224.
  • Patients who have had progressive disease while receiving irinotecan and temozolomide in combination will be excluded from the Phase 2 EWS and DSRCT cohorts only.
  • Participants who are receiving any other anti-cancer agents for this condition.
  • Patients receiving strong P450 CYP1A2 and CYP3A4 inhibitors and/or inducers with 14 days of the first planned dose of PEEL-224. NOTE: levofloxacin is permitted and preferred over ciprofloxacin for patients needing a fluoroquinolone.
  • Patients who have received a solid organ or allogeneic stem cell transplant
  • Pregnant participants, given that the effects of PEEL-224 on the developing human fetus are unknown.
  • Breastfeeding mothers, because there is an unknown risk for adverse events in nursing infants secondary to treatment of the mother with PEEL-224.
  • Patients with a history of allergic reactions attributed to PEGylated drugs, camptothecins, temozolomide or vincristine.
  • Patients with uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements.

Study Design

Enrollment

63 participants

Anticipated

Allocation

Non randomized

Intervention Model

Sequential

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Phase 1: Dose Escalation PEEL-224 Dose Level 0

Up to 15 participants will be enrolled using a Bayesian design, the Continual Reassessment Method (CRM), to determine the maximum tolerated dose of PEEL-224 and starting at Dose Level 0. Transition to a lower dose level will be determined by types of dose-limiting toxicities observed per the protocol.

  • Baseline visit with assessments and imaging
  • Cycle 1 (21 day cycle):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Day 10: Myeloid growth factor (Pegfilgrastim or Filgrastim) administration 1x daily
  • Cycle 2 through End of Treatment (21 day cycles):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Imaging every 2 cycles until Cycle 6 and then every 3 cycles
  • End of study visit

experimental: Phase 1: Dose Escalation PEEL-224 Dose Level -1A

Transition to a lower dose level will be determined by types of dose-limiting toxicities observed per the protocol, otherwise establishment of the MTD/RP2D will be according to the CRM model.

  • Baseline visit with assessments and imaging
  • Cycle 1 (21 day cycle):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Day 10: Myeloid growth factor (Pegfilgrastim or Filgrastim) administration 1x daily
  • Cycle 2 through End of Treatment (21 day cycles):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Imaging every 2 cycles until Cycle 6 and then every 3 cycles
  • End of study visit

experimental: Phase 1: Dose Escalation PEEL-224 Dose Level -1B

Transition to a lower dose level will be determined by types of dose-limiting toxicities observed per the protocol, otherwise establishment of the MTD/RP2D will be according to the CRM model.

  • Baseline visit with assessments and imaging
  • Cycle 1 (21 day cycle):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Day 10: Myeloid growth factor (Pegfilgrastim or Filgrastim) administration 1x daily
  • Cycle 2 through End of Treatment (21 day cycles):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Imaging every 2 cycles until Cycle 6 and then every 3 cycles
  • End of study visit

experimental: Phase 1: Dose Escalation PEEL-224 Dose Level -2

Establishment of the MTD/RP2D will be according to the CRM design.

  • Baseline visit with assessments and imaging
  • Cycle 1 (21 day cycle):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Day 10: Myeloid growth factor (Pegfilgrastim or Filgrastim) administration 1x daily
  • Cycle 2 through End of Treatment (21 day cycles):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Imaging every 2 cycles until Cycle 6 and then every 3 cycles
  • End of study visit

experimental: Phase 1: Dose Escalation PEEL-224 Dose Level 1

Escalation to Dose Level 2 or establishment of the MTD/RP2D will be determined by the CRM design.

  • Baseline visit with assessments and imaging
  • Cycle 1 (21 day cycle):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Day 10: Myeloid growth factor (Pegfilgrastim or Filgrastim) administration 1x daily
  • Cycle 2 through End of Treatment (21 day cycles):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Imaging every 2 cycles until Cycle 6 and then every 3 cycles
  • End of study visit

experimental: Phase 1: Dose Escalation PEEL-224 Dose Level 2

Establishment of the MTD/RP2D will be determined by the CRM design.

  • Baseline visit with assessments and imaging
  • Cycle 1 (21 day cycle):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Day 10: Myeloid growth factor (Pegfilgrastim or Filgrastim) administration 1x daily
  • Cycle 2 through End of Treatment (21 day cycles):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Imaging every 2 cycles until Cycle 6 and then every 3 cycles
  • End of study visit

experimental: Phase 2: Dose Expansion Ewing Sarcoma

Administration of PEEL-224 will be at the RP2D, and safety monitoring rules will be applied for the occurrence of dose-limiting toxicities. 15 participants will be enrolled and will complete:

  • Baseline visit with assessments and imaging
  • Cycle 1 (21 day cycle):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Day 10: Myeloid growth factor (Pegfilgrastim or Filgrastim) administration 1x daily
  • Cycle 2 through End of Treatment (21 day cycles):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Imaging every 2 cycles until Cycle 6 and then every 3 cycles
  • End of study visit

experimental: Phase 2: Dose Expansion DSRCT

Administration of PEEL-224 will be at the RP2D, and safety monitoring rules will be applied for the occurrence of dose-limiting toxicities. 15 participants will be enrolled and will complete:

  • Baseline visit with assessments and imaging
  • Cycle 1 (21 day cycle):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Day 10: Myeloid growth factor (Pegfilgrastim or Filgrastim) administration 1x daily
  • Cycle 2 through End of Treatment (21 day cycles):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Imaging every 2 cycles until Cycle 6 and then every 3 cycles
  • End of study visit

experimental: Phase 2: Dose Expansion Other Sarcoma

Administration of PEEL-224 will be at the RP2D, and safety monitoring rules will be applied for the occurrence of dose-limiting toxicities. 15 participants will be enrolled and will complete:

  • Baseline visit with assessments and imaging
  • Cycle 1 (21 day cycle):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Day 10: Myeloid growth factor (Pegfilgrastim or Filgrastim) administration 1x daily
  • Cycle 2 through End of Treatment (21 day cycles):

  • Days 1 through 5: Predetermined dose of Temozolomide 1x daily
  • Days 1 and 8: Predetermined dose of PEEL-224 1x daily and predetermined dose of Vincristine 1x daily
  • Imaging every 2 cycles until Cycle 6 and then every 3 cycles
  • End of study visit

Interventions

PEEL-224

Topoisomerase 1 inhibitor, 200mg amber vial, via intravenous (into the vein) infusion per protocol.

Temozolomide

Alkylating agent, 5, 20, 100, 140, 180, or 250 mg capsule, taken orally per standard of care.

Vincristine

Vinca alkaloid, 1 or 2mL vials, via intravenous (into the vein) infusion per institutional policy.

Pegfilgrastim

Myeloid growth factor administered per institutional standards.

Filgrastim

Myeloid growth factor administered per institutional standards.

Primary outcome measure

  • Maximum Tolerated Dose (MTD) (Phase 1) [ Time Frame: Up to 35 days ]
  • Number of Participants with Dose-Limiting Toxicities (Phase 1) [ Time Frame: Up to 35 days ]
  • Number of Participants with DLTs (Phase 2) [ Time Frame: Up to 35 days ]
  • Objective Response Rate EWS Cohort (Phase 2) [ Time Frame: Up to 5 years (based on accrual duration of 2 years) ]
  • Objective Response Rate DSRCT Cohort (Phase 2) [ Time Frame: Up to 5 years (based on accrual duration of 2 years) ]

Central Contacts and Locations

Central contacts

Locations

Dana-Farber Cancer Institute

Recruiting

Boston, Massachusetts, United States, 02115

Contacts

Principal Investigator:

David Shulman, MD

More Information

Sponsor

David S Shulman, MD

Last update posted

Feb 19, 2026

Last verified

Feb, 2026

Keywords

  • Sarcoma
  • Sarcoma, Ewing
  • Desmoplastic Small Round Cell Tumor
  • Refractory Sarcoma
  • Relapsed Sarcoma
  • osteosarcoma
  • rhabdomyosarcoma

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by David S Shulman, MD on 2026-02-19.