Tempe-Based GT Medical Technologies closes oversubscribed $100M Series E, its largest raise yet

Tempe medical device company GT Medical Technologies has closed an oversubscribed $100 million Series E financing, the largest round in the firm's history and one of the biggest venture raises an Arizona health-tech company has landed this year.

The financing was led by new investor Viking Global Investors, the Connecticut-based firm that manages roughly $52 billion across public and private investments. Existing backers MVM Partners, Gilde Healthcare, Evidity Health Capital, Medtech Venture Partners and FemHealth Ventures also took part. The round pushes GT Medical's total capital raised past $240 million since the company was founded in 2017.

Viking's involvement is the detail worth watching. The firm is a generalist investment house rather than a dedicated medtech fund, and its willingness to lead a nine-figure round for a clinical-stage device maker points to broader crossover interest in companies with hard randomized-trial data behind them. For a Tempe firm to draw that kind of capital is a meaningful marker for the wider Arizona life-sciences ecosystem.

GT Medical plans to use the money to scale commercial and operational work behind GammaTile, its FDA-cleared radiation therapy implant, and to fund the recently launched BRIDGES trial in patients with newly diagnosed glioblastomas.

What GammaTile does

GammaTile is a bioresorbable collagen implant embedded with radiation sources. A neurosurgeon places it directly into the cavity during brain tumor removal surgery, delivering targeted radiation to the resection site at the point when residual cancer cells are at their lowest level.

Conventional treatment leaves a gap between surgery and the start of radiation so the wound can heal. GammaTile is designed to remove that delay by starting treatment immediately, concentrating the dose where the tumor was and reducing the risk of regrowth. The device first won FDA 510(k) clearance in 2018 for recurrent brain tumors, with the label expanded in 2020 to cover newly diagnosed malignant tumors.

Trial data behind the raise

The timing follows the release last month of final results from GT Medical's ROADS randomized controlled trial, which studied GammaTile in patients with newly diagnosed brain metastases. The data was selected for oral presentation at the 2026 American Society of Clinical Oncology conference.

According to the company, GammaTile cut the risk of tumor recurrence by 93% and the risk of death at 12 months by 41% compared with standard care. The 12-month surgical-bed recurrence rate was 1.3% with GammaTile versus 15.4% for standard treatment, and 24-month overall survival reached 61.7% versus 35.7%.

"This financing is validation of GammaTile's potential to be a standard of care treatment for operable brain tumors and will accelerate our ability to bring this important therapy to even more patients," said Per Langoe, chief executive officer at GT Medical Technologies.

The company still faces the familiar hurdles of medtech commercialization, including surgeon adoption, training and consistent insurance coverage across health systems. But with fresh capital and trial results in hand, GT Medical is positioning GammaTile as a candidate for standard-of-care status in operable brain tumors.