GT Medical Technologies closed an oversubscribed $100M Series E, announced June 9, 2026. Viking Global Investors led as a new investor. MVM Partners, Gilde Healthcare, Evidity Health Capital, Medtech Venture Partners and FemHealth Ventures participated. Total raised is $214M across rounds of $16M in 2020, $45M in 2023, $53M in 2025 and this one.
GammaTile is a bioresorbable radiotherapy implant placed in the resection cavity during brain tumor surgery, so radiation starts at the surgical bed immediately. FDA first cleared it under K180515 in July 2018, with Isoray Medical as applicant, for recurrent brain tumors. GT Medical cleared it for newly diagnosed malignant tumors under K190839 in January 2020, then again under K221539 in November 2022. Product code is KXK, a brachytherapy source under 21 CFR 892.5730.
ROADS randomized patients with newly diagnosed operable brain metastases. Twelve-month surgical-bed recurrence was 1.3% with GammaTile against 15.4% with surgery plus stereotactic radiation. Overall survival at 24 months was 61.7% against 35.7%. More than 150 US cancer centers now offer the treatment. CEO Per Langoe said the money goes to commercial and operational investment and to the BRIDGES randomized trial in newly diagnosed glioblastoma. A Class II brachytherapy source with randomized survival data is an unusual combination. The 510(k) got it to market; the RCT is what gets it paid.