The Ewing Sarcoma Treatment Landscape

Subheadings go here.

How To Use This Information

New possibilities continue to develop, but figuring out what’s right for you or your child is overwhelming. It feels like the world’s worst “choose your own adventure” book—where the stakes couldn’t be higher and the choices are rarely clear.

Think of this page as a starting point—a way to explore what’s out there, ask thoughtful questions, and move forward with as much clarity and confidence as possible.
Use this content in partnership with your medical team.

Because this landscape is changing quickly, we welcome your help in keeping this resource up to date. If you notice something that should be added, updated, or clarified, please let us know. This is not an exhaustive list, and inclusion here does not necessarily imply endorsement—just as exclusion does not mean an option isn’t worth considering.

Second Opinions

Remote consults, tumor boards, and more.

New Diagnosis

Frontline options for newly diagnoses patients.

Relapsed & Refractory Trials

Eager to explore life’s big questions?
Searching for a sense of belonging?

Local Control Considerations

Surgery, Radiation and More

Maintenance

Leave us alone, cancer.

Other Options/Precision Med

Stem Cell, AngioA, etc?

Second Opinions

NEWS Tumor Board

The National Ewing Sarcoma Tumor Board (NEWS) pulls multidisciplinary experts from across the country to consult on cases. Leaders in the fields of pediatric & medical oncology, radiation oncology, orthopedic oncology, radiology/IR, pathology and other surgical specialties participate representing leading institutions such as Dana-Farber, Duke, Nationwide Children’s, Seattle Children’s, and Stanford. Recommendations will be delivered back to your oncologist (not to the patient directly). 

Your oncologist can submit your case with a question for the board.
Learn More »

Finding Second Opinions

Ewing Sarcoma is rare enough that the average oncologist will see only a handful of cases in their career. That's not a criticism of your local team — it's just the reality of this disease. Expertise matters enormously here, and the doctors who live and breathe sarcoma every day think about it differently than those who don't.

If you are not already being treated at a sarcoma center, seek a second opinion from one. Most offer remote consultations, which means you don't necessarily have to travel. By establishing a relationship with a specialist early, you have someone to reach out to quickly when challenges arise.

NOTE: If your local team is resistant to collaborating with a sarcoma specialist — that's concerning. A confident, experienced oncologist will welcome the extra eyes.

Sarcoma Centers

Did we miss a strong Sarcoma Center? Let us know.

Trials & Options for Newly Diagnosed Patients

IN:Formation Next Generation Sequencing Program

Dr. Giselle Sholler | Penn State Health & Beach Childhood Cancer Consortium
The IN:Formation Project uses advanced genomic sequencing to reveal the mechanics, drivers, and targets in your child's unique tumor. Patients may participate in this program when their tumor is biopsied or during surgical local control. Participating helps you and your team learn more about your tumor while also contributing to research. There is an arm of this program that includes treatment recommendations.

This is considered an observational trial. Participation does not include intervention, but it does provide valuable information that may be helpful in relapsed or refractory situations.

Ewing’s U Episode:May 2022(Dr. Sholler and this program have moved to Penn State Health)
ClinicalTrials.gov:NCT04715178
Location: Multiple Locations, US
Status: Recruiting
Little Warrior Foundation has provided financial support to this program. ⚔️


METTSEO Trial

Dr. Matteo Trucco & Dr. Jonathan Metts | Cleveland Clinic & H. Lee Moffitt Cancer Center
This Phase 1 trial tests an alternative strategy for widely metastatic Ewing sarcoma by optimizing the sequencing of existing chemotherapy rather than introducing a new drug. METTSEO rotates multi-agent regimens every ~6–8 weeks to limit resistance, applying an evolution-based approach: an initial “first strike” to reduce tumor burden, followed by sequential “second strikes” targeting resistant cells and a maintenance phase to suppress regrowth. The goal is to improve historically poor outcomes by disrupting tumor adaptation.

Ewing's U Episode: April 2025
ClinicalTrials.gov: NCT07194044
Location: Multiple Locations, US
Status: Recruiting


INTER-EWING-1 — Regorafenib + Optimized Standard Therapy

Prof. Bernadette Brennan | University of Manchester / CRUK Clinical Trials Unit

Multi-tyrosine kinase inhibitor + multimodal therapy optimization.
This Phase 2 international trial tests whether adding regorafenib—a multi-tyrosine kinase inhibitor—to standard chemotherapy improves outcomes in newly diagnosed Ewing sarcoma, while simultaneously optimizing radiotherapy dosing and evaluating maintenance chemotherapy. Patients are randomized across multiple arms examining targeted therapy, dose-adjusted radiation, and extended low-dose chemotherapy. The goal is to improve survival by enhancing standard treatment across multiple points of care rather than introducing a single new regimen.

Ewing's U Episode: May 2025
UK Trial Information: Bone Cancer Research Trust
Location: International. UK, Europe, Australia, New Zealand (Not currently offered in the US)
Status: Active

Options for Relapsed & Refractory Disease

Common Relapse Protocols

Two chemotherapy combinations are most commonly recommended starting points when Ewing sarcoma comes back. Neither is experimental — both have been used for years, are familiar to most pediatric oncology teams, and have similar response rates of roughly 25–35%. The choice between them usually comes down to what your child has already received, current blood counts, and which side-effect profile fits your family's situation, as well as the availability and interest in clinical trials.

Irinotecan + Temozolomide (often called "I/T" or "Tem-Iri")

A lower-intensity regimen that's typically given outpatient. Temozolomide is an oral pill taken at home for five days; irinotecan is an IV infusion given over the same five days, often in clinic without hospitalization. Together they damage cancer-cell DNA and prevent the cells from repairing it. Common side effects: diarrhea (sometimes significant — irinotecan is known for this), nausea, fatigue, and lower blood counts. Some teams include Vincristine in this protocol (VIT).

A practical note worth making: many of the trials in this list (INBRX-109, ONITT, the CAMPFIRE abemaciclib arm, silmitasertib + VIT) are built directly on top of I/T or VIT. So if your child tolerates and responds to I/T, several of those trials become natural next steps that layer a targeted therapy on a backbone you already know works for them.

Cyclophosphamide + Topotecan (often called "C/T")

A more intensive regimen, usually given as a five-day inpatient stay repeated every three weeks. Both drugs are IV. Cyclophosphamide damages DNA directly; topotecan, like irinotecan, blocks the cancer cell's DNA-repair machinery. C/T tends to drop blood counts more deeply than I/T, which means more transfusions, more time in the hospital, and a higher risk of fevers and infections during the low-count window. It's a meaningful step up in intensity, but for some kids — especially those who've already had a course of irinotecan — switching to a different mechanism with C/T is the right next move.

Comparing The Protocols:

The European rEECur trial directly compared the most common relapse regimens head-to-head (I/T, C/T, gemcitabine/docetaxel, and high-dose ifosfamide). The takeaway is often summarized as "no single clear winner" — high-dose ifosfamide showed a numerical advantage on some endpoints but is much harder on the body, while I/T and C/T held up well as more livable options. This is why your team's recommendation will likely be individualized rather than formulaic. And why consulting with a Sarcoma Center is important.

SARC037 — Trabectedin + Low-Dose Irinotecan

Dr. Patrick Grohar | CHOP
EWS::FLI1 suppressor + topoisomerase I inhibitor.
This study pairs trabectedin — a drug shown to suppress the EWS::FLI1 fusion protein that drives Ewing sarcoma — with low-dose irinotecan. Trabectedin reverses the EWS::FLI1 transcriptional program, and low-dose irinotecan sustains that effect. Phase 2 results (2024) reported a 33% response rate and ~48% 6-month progression-free survival in relapsed/refractory Ewing sarcoma.

Ewing's U Episode:July 2023
ClinicalTrials.gov:NCT04067115
Location: Multiple Locations, US
Status: Completed REMOVE?



Clinical Trials

While we try to keep this resources as up to date as possible, please refer to ClinicalTrials.gov for the most up to date options and trial status information.

SARC037 — Trabectedin + Low-Dose Irinotecan

Dr. Patrick Grohar | CHOP
EWS::FLI1 suppressor + topoisomerase I inhibitor.
This study pairs trabectedin — a drug shown to suppress the EWS::FLI1 fusion protein that drives Ewing sarcoma — with low-dose irinotecan. Trabectedin reverses the EWS::FLI1 transcriptional program, and low-dose irinotecan sustains that effect. Phase 2 results (2024) reported a 33% response rate and ~48% 6-month progression-free survival in relapsed/refractory Ewing sarcoma.

Ewing's U Episode: July 2023
ClinicalTrials.gov:NCT04067115
Location: Multiple Locations, US
Status: Completed


SARC037 — Trabectedin + Low-Dose Irinotecan

Dr. Patrick Grohar | CHOP
EWS::FLI1 suppressor + topoisomerase I inhibitor.
This study pairs trabectedin — a drug shown to suppress the EWS::FLI1 fusion protein that drives Ewing sarcoma — with low-dose irinotecan. Trabectedin reverses the EWS::FLI1 transcriptional program, and low-dose irinotecan sustains that effect. Phase 2 results (2024) reported a 33% response rate and ~48% 6-month progression-free survival in relapsed/refractory Ewing sarcoma.

Ewing's U Episode: July 2023
ClinicalTrials.gov:NCT04067115
Location: Multiple Locations, US
Status: Completed

Local Control

Surgical Decision Resource Guide

The Osteosarcoma Decision Aid is one of the most thorough patient-facing resources we know of for thinking through the surgical decisions that come with a bone sarcoma diagnosis. It was built specifically for osteosarcoma — and is upfront about that — but for Ewing sarcoma families whose child's tumor is in a long bone, the surgical pathways it walks through (limb salvage with an internal prosthesis or allograft, amputation, rotationplasty) and the trade-offs it lays out apply directly to your decision too.

Surgical teams typically explain these options across multiple appointments, in fragments — often during one of the most overwhelming weeks of your life. The Decision Aid pulls everything into one place at your own pace: what each option actually means day-to-day, how functional outcomes compare over time, complication and revision rates, what changes when the patient is still growing, and stories from families who chose each path. Many parents have told us this is the resource that finally let the surgical conversation make sense.

A few caveats worth naming up front: pelvic and chest-wall Ewing tumors involve different surgical considerations than long-bone disease, so the Decision Aid is less directly applicable there — though the general framework (oncologic vs. functional trade-offs, questions to ask, how to weigh family priorities) still translates. Some details around chemotherapy timing differ between osteosarcoma and Ewing, but the surgical decision itself is framed similarly. And this is meant to support — not replace — the conversation with your pediatric orthopedic oncology team. The best way to use it is to read through, mark down your questions, and bring those back to your team.

Visit the Osteosarcoma Decision Aid: osteosarcomadecisionaid.com

Ewing’s U Episode: June 2023


Discussion with Hillary

  • Cryoablation Trial & Ewings U?

  • SBRT? (Dr Murphy? Trial or just Ewings U?)

  • Proton vs. Photon?

  • Distraction Osteogenesis?

Maintenance Options

The question we get the most: “How do we keep it from coming back?”
Unfortunately, the answer isn’t straightforward. But here are the few resources we are aware of.

CHOA-NOME Protocol

UPDATE ALL SUPPORTING CONTENT
EWS::FLI1 suppressor + topoisomerase I inhibitor.
This study pairs trabectedin — a drug shown to suppress the EWS::FLI1 fusion protein that drives Ewing sarcoma — with low-dose irinotecan. Trabectedin reverses the EWS::FLI1 transcriptional program, and low-dose irinotecan sustains that effect. Phase 2 results (2024) reported a 33% response rate and ~48% 6-month progression-free survival in relapsed/refractory Ewing sarcoma.

Ewing's U Episode:
July 2023
ClinicalTrials.gov:
NCT04067115
Location: Multiple Locations, US
Status: Completed


CABOZANTINIB

UPDATE ALL SUPPORTING CONTENT
EWS::FLI1 suppressor + topoisomerase I inhibitor.
This study pairs trabectedin — a drug shown to suppress the EWS::FLI1 fusion protein that drives Ewing sarcoma — with low-dose irinotecan. Trabectedin reverses the EWS::FLI1 transcriptional program, and low-dose irinotecan sustains that effect. Phase 2 results (2024) reported a 33% response rate and ~48% 6-month progression-free survival in relapsed/refractory Ewing sarcoma.

Ewing's U Episode:
July 2023
ClinicalTrials.gov:
NCT04067115
Location: Multiple Locations, US
Status: Completed


DFMO Maintenance Trial

UPDATE ALL SUPPORTING CONTENT
EWS::FLI1 suppressor + topoisomerase I inhibitor.
This study pairs trabectedin — a drug shown to suppress the EWS::FLI1 fusion protein that drives Ewing sarcoma — with low-dose irinotecan. Trabectedin reverses the EWS::FLI1 transcriptional program, and low-dose irinotecan sustains that effect. Phase 2 results (2024) reported a 33% response rate and ~48% 6-month progression-free survival in relapsed/refractory Ewing sarcoma.

Ewing's U Episode:
July 2023
ClinicalTrials.gov:
NCT04067115
Location: Multiple Locations, US
Status: Completed


Monitoring: Liquid Biopsy

UPDATE ALL SUPPORTING CONTENT
The science has not been validated but other patients are taking matters into their own hands and using it commercially (testing is expensive and not covered by insurance).

Signatera, Foundation Medicine, Caris, BostonGene, etc. 

Dr. Pete Anderson | Cleveland Clinic

One of the premier Ewing Sarcoma experts, Dr. Pete conducts hundreds of remote consults per year. He has retired from the clinic, but sill offers virtual guidance. Appointments can be made via his admin, Sammi Garzone: garzones@ccf.org

Dr. Jonathan Gill & Dr. Karen Moody | MD Anderson

This team offers a much sought-after integrative oncology approach—they treat Ewing sarcoma with both cutting-edge medical therapy and comprehensive symptom, emotional, and quality-of-life support. Do we know how this team sets up second opinions? Virtual? In Person only? By referral?