Collagen Implant May Improve Local Control of Metastatic Brain Tumors

"These interim results suggest that [GammaTile] not only achieves local control but does so with superiority over the existing standard of care," according to study investigator Jeffrey S. Weinberg, MD, FAANS, FACS.

Treatment with GammaTile, a bioabsorbable collagen implant, reduced the risk of tumor recurrence or death compared with standard of care (SOC) among patients with operable, newly diagnosed brain metastases, according to a press release on interim findings from the phase 3 ROADS trial (NCT04365374).1

According to data on 168 patients presented at the 2025 Congress of Neurological Surgeons in Los Angeles, California, GammaTile reduced the risk of tumor recurrence or death by more than 50% vs standard therapy, demonstrating superiority in the study’s primary end point (HR, 0.42; P = .0024). Additionally, GammaTile improved overall protection from worrisome radiographic brain changes; more than half of the patients who underwent treatment with GammaTile remained free from tumor regrowth and radiation-associated tissue damage, whereas more than half of those who received SOC experienced one of these events by 18 months (HR, 0.32; P = .018).

Interim data showed that GammaTile produced significant efficacy gains without an increase in safety concerns. Investigators noted a low and comparable incidence of treatment-related adverse effects between the GammaTile and SOC arms.

“Although the ROADS trial focused on patients with operable brain metastases, the study reflects real-world treatment patterns, where many patients have a large metastasis that needs surgery and small brain metastases that can be well managed with stereotactic radiation without removal. In such cases, patients [randomly assigned] to the GammaTile arm received GammaTile radiation for the operable tumor and stereotactic radiation for the small metastases,” trial investigator Jeffrey S. Weinberg, MD, FAANS, FACS, professor of neurosurgery, deputy chair, and vice chair of clinical operations in the Department of Neurosurgery at The University of Texas MD Anderson Cancer Center in Houston, stated in the press release.1 “These interim results suggest that this approach not only achieves local control but does so with superiority over the existing standard of care. My colleague, Thomas H. Beckham, MD, PhD, and I agree this evidence may redefine how we treat this disease.”

Developers engineered GammaTile with embedded radiation seeds to treat patients with operable brain tumors. The modality is placed into the surgical cavity at the time of tumor resection, which may enable the direct delivery of radiotherapy to provide immediate, localized treatment. Investigators hypothesize that treatment with GammaTile may help target cancer cells at their lowest levels, effectively preventing regrowth while reducing the amount of healthy brain tissue exposed to radiation.

In the phase 3 ROADS trial, a total of 230 patients were randomly assigned to receive treatment with surgical resection plus GammaTile therapy or surgery plus SOC stereotactic radiation therapy.2 Patients underwent treatment at more than 30 centers across the US; investigators completed random assignment of patients in August 2025.

The trial’s primary end point was surgical bed recurrence-free survival from the time of random assignment to a maximum of 2 years following radiation. Secondary end points included overall survival, quality-of-life assessments, neurocognitive status assessments, and physical functioning assessments.

Patients 18 years or older with 1 to 6 newly diagnosed brain metastases, 1 primary index lesion planned for surgical resection, and a Karnofsky performance status of at least 70 were eligible for enrollment in the trial. Other eligibility criteria included having stable systemic disease or a minimum life expectancy of 6 months as well as adequate renal and hepatic function to undergo surgery.

“The interim data from the ROADS trial are the first randomized, multicenter evidence showing the superiority of starting radiation immediately at the time of tumor removal with GammaTile for operable brain metastases. These results highlight the importance of immediate, targeted radiation therapy,” Michael Garcia, MD, MS, chief medical officer at GT Medical Technologies, the developer of GammaTile, concluded.1

References

1. Breakthrough clinical trial confirms that GammaTile delivers superior tumor control compared to standard of care for patients with newly diagnosed operable brain metastases. News release. GT Medical Technologies. October 21, 2025. Accessed October 21, 2025. https://tinyurl.com/38wdwenh
2. Post-surgical stereotactic radiotherapy (SRT) versus GammaTile-ROADS (Radiation One and Done Study). ClinicalTrials.gov. Updated October 7, 2025. Accessed October 21, 2025. https://tinyurl.com/k99juktp