Clinical trial Recruiting at 1 site Phase 1 Interventional Ages 18 and up

Omitting brain metastasis radiation after tumor removal when CNS-active therapy is used

Official title: OBSERVE: A Pilot Study Of Omission Of Brain Metastasis Stereotactic Radiosurgery Following Resection With CNS-Active Systemic Therapy

Run by M.D. Anderson Cancer Center · NCT07655583 · Data updated 2026-11-12

This pilot study tests whether patients with resected brain metastases from melanoma or NSCLC can skip post-operative brain radiation while receiving CNS-active systemic therapy.

Quick facts

PhasePhase 1
Study typeInterventional
Ages18 Years and up
SexAll
Enrollment20 (estimated)
SponsorM.D. Anderson Cancer Center
Academic / other
Drugs / interventionsipilimumab, nivolumab, osimertinib, brigatinib, alectinib, lorlatinib, radiation
Locations1 site (Houston, Texas)
StatusRecruiting
StartedMay 27, 2026
Main results expectedJune 30, 2028
Study endsJune 30, 2030
Registry record updatedSeptember 15, 2026
Trial IDNCT07655583 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Adults 18 or older with resected brain metastases from NSCLC or melanoma, gross total resection confirmed, and planned CNS-active systemic therapy.

Probably not a fit

Patients whose disease recurs in the brain despite CNS-active therapy may not benefit and could require radiation or other treatments.

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

What this trial studies

This is a Phase 1 pilot trial exploring if highly CNS-active systemic therapy can replace post-operative radiation after surgical removal of brain metastases. Eligible participants are adults with a recent gross total resection of brain metastases from NSCLC or melanoma and good performance status. The study focuses on recurrence risk in the surgical bed without immediate radiation, while patients receive systemic treatment that acts in the CNS. Multidisciplinary review ensures appropriate patient selection and monitoring for intracranial control and safety. It is conducted at MD Anderson Cancer Center and involves careful imaging and pathology review to confirm each enrolled case.

Why it matters

Potential benefit: If successful, participants may avoid the risks and side effects of brain radiation while maintaining disease control.

How similar studies have gone: Previous approaches with CNS-active systemic therapy plus deferred or omitted radiation have shown mixed results and this remains an exploratory area.

Who can join: the full rules

Show full inclusion / exclusion criteria
Eligibility Criteria

1. Age ≥ 18 years.
2. ECOG performance status ≤ 2.
3. Participants with a resected brain metastasis with gross total resection and pathologic confirmation of NSCLC or melanoma. Gross total resection must be confirmed based on a review of the operative report, pathology, and all post-operative images available at the time of enrollment.
4. Brain metastasis resection occurred ≤ 5 weeks ago.
5. Additional prior surgeries, including Laser Interstitial Thermal Therapy (LITT), to the same or nearby location are permitted, provided that residual disease or local recurrence is confirmed pathologically at the most recent resection.
6. The resected lesion has never previously been targeted by radiotherapy.
7. Evaluation by a brain metastasis multidisciplinary team (BM-MDT), consisting of a medical oncologist (can be the patient's primary medical oncologist), a radiation oncologist who regularly performs SRS, and a neurosurgeon, and agreement that the intracranial cavity does not or will not require immediate post-operative radiation (i.e. it is judged to be safe to omit post-operative radiation). This BM-MDT evaluation can take place in clinic or during a multidisciplinary conference, either before or after the surgical resection. If the BM-MDT evaluation was before the surgical resection, there can be no new findings in the interim (e.g. during or after the surgical resection) that would change the BM-MDT's recommendation, as determined by one or more of the patient's treating physicians.
8. Documentation by the patient's primary medical oncologist of a planned study systemic therapy regimen consisting of one of the following: dual-agent immune checkpoint inhibitors (e.g. ipilimumab and nivolumab) for melanoma, osimertinib for EGFR Mutant (e.g. Exon 19 deletion; L858R) NSCLC, and brigatinib, alectinib, or lorlatinib for ALK rearranged/fusion positive NSCLC. As new agents are approved, other highly-CNS active tyrosine kinase inhibitors for participants with NSCLC may be included at the discretion of the principal investigator.
9. For a participant with more than one recently resected brain metastasis that meets eligibility criteria #3-#7 above, it is permissible (but not mandated) for more than one surgical cavity to proceed without immediate post-operative radiation. All other intracranial disease must proceed with treatment according to standard-of-care practices at the time of enrollment. This may include treatment with SRS or observation if clinically appropriate.
10. Regarding prior systemic therapy:

    1. For participants with melanoma: no prior disease progression on any immune checkpoint inhibitor agent and ≥ 6 months between the last dose of any immune checkpoint inhibitor agent and initiation of the study systemic therapy regimen.
    2. For participants with EGFR Mutant NSCLC: no prior disease progression on any EGFR-targeted tyrosine kinase inhibitor and ≥ 6 month between the last dose of any EGFR-targeted tyrosine kinase inhibitor and initiation of the study systemic therapy regimen.
    3. For participants with ALK rearranged/fusion positive NSCLC: no prior disease progression on any ALK-targeted tyrosine kinase inhibitor and ≥ 6 month between the last dose of any ALK-targeted tyrosine kinase inhibitor and initiation of the study systemic therapy regimen.
11. This study will allow non-English speaking subjects to be enrolled. Verbal Translation Preparative Sheet (VTPS) will be used if a translated consent form is not available in the subject's language. The consent form will be translated into the language of the subject after 2 or more occurrences. This will apply to any MD Anderson patient.

Exclusion Criteria

1. History of known leptomeningeal involvement (radiographic or cytological).
2. Subjects that have previously received or are currently planned for whole brain radiotherapy.
3. Prior unacceptable toxicity on one or more of the agents comprising the planned study systemic therapy.
4. Cognitively impaired subjects with a major medical, neurologic or psychiatric condition who are judged as unable to fully comply with study therapy or assessments should not be enrolled.
5. Participant unable to receive a brain MRI (implanted metal devices or foreign bodies) or MRI contrast.
6. Pregnancy or plans to become pregnant during the duration of the study.

Where it's running

  • MD Anderson Cancer Center
    Houston, Texas, 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.