WSW, NY, October 19th, 2026, FinanceWire
FDA clearance doubles REGAIN’s permitted enrollment and broadens its clinical assessments, as Alpha Tau prepares to present updated results in November.
Alpha Tau Medical (NASDAQ: DRTS) announced on October 19 that the FDA has cleared its U.S. brain cancer trial to double in size, giving an experimental treatment associated with striking early tumor responses a larger clinical test. The company also set a date for its next update: November 13, when new REGAIN trial data are scheduled for presentation at the Society for Neuro-Oncology’s annual meeting in Philadelphia.
The expanded study can enroll up to 20 patients, compared with 10 previously, across three authorized U.S. academic cancer centers. It also adds measures of how long patients live without their disease progressing and how treatment affects their quality of life. For Alpha Tau, that creates an opportunity to investigate whether its early imaging results can translate into a broader clinical benefit.
A difficult cancer leaves little room for conventional treatment
REGAIN focuses on recurrent glioblastoma, an aggressive brain cancer that has returned after previous treatment. Its patients have already received radiation to the central nervous system, and their recurrent tumors cannot be surgically removed. That places the study in a particularly difficult setting: a growing tumor needs treatment inside an organ where preserving surrounding tissue is essential.
The National Cancer Institute describes the constraints facing these patients. Repeat radiation requires careful judgment because of the risk of cognitive damage and tissue death. Further surgery is an option for some, but many patients cannot undergo another operation because of their condition or the tumor’s location. A treatment capable of attacking a tumor locally while limiting exposure around it could address a meaningful gap.
Alpha Tau is testing precisely that possibility. Its Alpha DaRT technology places tiny radioactive sources containing radium-224 directly inside a tumor. As the material decays, it releases short-lived radioactive atoms that spread a limited distance and emit powerful alpha particles. The goal is to damage tumor cells while sparing nearby healthy tissue.
For brain tumors, the company uses an image-guided delivery system that works with standard surgical navigation platforms. Sources are placed through a small opening in the skull, without requiring the larger opening used in an open craniotomy. The approach puts both the radiation and its placement at the center of the treatment strategy.
The first patients gave the program a reason to grow
In May, Alpha Tau reported interim results from the first three REGAIN patients, treated at The Ohio State University. Two had complete responses on repeated MRI scans, meaning all enhancing tumor lesions had disappeared under the study’s response criteria. The third had stable disease, with a 30% reduction in tumor dimension. All three had local disease control at the May 3 data cutoff.
The company also reported one treatment-associated grade 3 serious adverse event, a seizure with temporary paralysis that resolved after steroids. These observations came from a small, uncontrolled feasibility and safety study, but they established a concrete signal for further investigation. In June, the FDA cleared enrollment of the remaining patients under the original 10-patient design and authorized two additional U.S. sites.
Today’s expansion gives the next phase of that investigation more substance. Alongside overall survival and local tumor control, the protocol now tracks progression-free survival, the length of time before the disease worsens, and includes regular quality-of-life assessments. It also permits enrollment of patients with IDH-mutant grade 4 tumors, a genetically defined brain-tumor category classified separately from glioblastoma.
Those measurements could help explain what tumor control means for patients beyond a scan. Chief Medical Officer Robert Den described the challenge as “extending survival while preserving neurological function and quality of life.” The revised study is designed to collect evidence across those dimensions.
November brings the next public test of the story
Alpha Tau says that, based on initial discussions, data from the expanded study may support future market-submission requirements in this disease. That remains a potential development pathway, with Alpha DaRT investigational for recurrent glioblastoma. The updated protocol also provides for another interim analysis six months after the fifth patient’s treatment, which occurred in July.
The nearer milestone is November 13. Principal investigator Dr. Joshua Palmer’s accepted SNO presentation is scheduled to include new REGAIN data, marking the study’s first appearance at a scientific meeting. The trial has moved from three patients’ early responses toward a larger, more informative clinical program. Whether that signal deepens as the evidence grows is now a specific, approaching question, giving Alpha Tau’s brain cancer program a fresh reason to command attention.
Recent News Highlights from Alpha Tau (NASDAQ: DRTS)
Alpha Tau to Participate in October Investor Conferences
Alpha Tau to Participate in September Investor Conferences
Alpha Tau Announces Second Quarter 2026 Financial Results and Provides Corporate Update
Alpha Tau Registers for Dual Listing on the Tel Aviv Stock Exchange (TASE)
Important Disclaimers and Disclosures: The author, Wall Street Wire, is a content and media technology platform that connects the market with under-the-radar companies. The platform operates a network of industry-focused media channels spanning finance, biopharma, cyber, AI, and additional sectors, delivering insights on both broader market developments and emerging or overlooked companies. Wall Street Wire is not a broker-dealer or investment adviser. References to market size estimates, valuations, price targets, or other third-party data are provided strictly for informational purposes. Wall Street Wire receives cash compensation on behalf of Alpha Tau Medical Ltd. (the “Issuer”) from a related party or shareholder of the Issuer for coverage and awareness services, which are provided on an ongoing subscription basis. The content above is a form of paid advertising and promotion and is for informational purposes only and does not constitute financial or investment advice. This article may contain forward-looking statements about the Issuer’s products, plans, or prospects that are subject to risks and uncertainties; actual results may differ materially, and readers should review the Issuer’s public filings on SEC EDGAR (sec.gov/edgar) for full risk factors. Market size figures, research estimates, or other third-party data referenced in this article are quoted from publicly available sources believed to be reliable; however, we do not independently verify or endorse them, and additional figures or estimates may exist. Full compensation details, information about the operator of Wall Street Wire, and the complete set of disclaimers and disclosures applicable to this content are available at: wallstwire.ai/disclosures. This article should not be considered an official communication of the Issuer. Images may be computer generated and are for entertainment and visualization purposes only, and may not be an accurate or exact depiction of the technology.