DRTS Stock Surges Pre-Market Even As Retail Traders Debate ‘Too Small’ Brain Cancer Trial Data

• The third patient showed stable disease with a 30% reduction in tumor size.
• Alpha Tau reported no unexpected serious adverse events through May 3, 2026.
• As of the cutoff date, none of the patients showed signs of cancer returning or lingering side effects from the procedure.

Shares of Alpha Tau Medical (DRTS) surged more than 20% in pre-market trading on Monday, after the biotech firm reported encouraging interim results from a trial evaluating experimental alpha-radiation therapy for recurrent glioblastoma, one of the deadliest and most treatment-resistant brain cancers.

If the pre-market levels hold at market open, DRTS stock would trade at its highest levels since August 2022.

Alpha DaRT Shows Promise In Potential Treatment Of GBM

Interim results from the closely watched U.S. REGAIN trial evaluating Alpha DaRT for recurrent glioblastoma (GBM) showed that two of the first three patients treated achieved complete responses, with MRI scans confirming the disappearance of all visible tumor lesions following treatment.

The third patient showed stable disease with a 30% reduction in tumor size.

DRTS’ Safety Review Supports Trial Progress

The interim data were reviewed as part of an FDA-requested safety analysis following treatment of three patients between December 2025 and March 2026.

Alpha Tau reported no unexpected serious adverse events (SAEs) through May 3, 2026. One patient experienced a treatment-related seizure with temporary paralysis classified as a grade 3 serious adverse event, though the condition was resolved with steroid treatment. The results were defined by Response Assessment in Neuro-Oncology (RANO) criteria, Alpha Tau said.

As of the cutoff date, none of the patients showed signs of cancer returning or lingering side effects from the procedure.

Alpha DaRT Is Being Tested For Pancreatic Cancer Treatment

Last month, the U.S. Food and Drug Administration (FDA) approved an expansion of Alpha Tau Medical IMPACT pancreatic cancer trial testing Alpha DaRT in combination with chemotherapy.

The multi-center study is currently being conducted across the U.S., Canada, and Israel in patients with inoperable pancreatic cancer. The trial is designed to evaluate the therapy’s safety and tolerability while also monitoring tumor response, survival outcomes, disease progression, and pain relief.

DRTS: Retail Says Trial Data Based On A ‘Far Too Small’ Sample

Retail sentiment turned ‘bullish’ from ‘extremely bullish’ a day earlier, amid ‘high’ message volumes.

While retail bulls piled in on the data, one user said “Three patients is far too small to draw conclusions.”

Another user expects the stock to climb to $17.5 before declining. It is currently trading at around $10.1.

The stock has jumped more than 67% so far this year.

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