Radiopharm Reports Durable Partial Response in RAD204 Phase 1 and Positive Phase 2b Results for RAD101
RADX sits 27% above its 52-week low of $3.62.
Summary
Radiopharm Theranostics reported a durable Partial Response in its Phase 1 trial of RAD204 and positive Phase 2b results for RAD101, meeting the primary endpoint and supporting advancement to a pivotal Phase 3 trial.
Key Events · Product Development and Regulatory · RADX
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RAD204 Phase 1 Durable Partial Response
The first patient in cohort 3 achieved a RECIST-confirmed Partial Response, with a 43% reduction in target lesions maintained through four cycles and progression-free beyond seven months. No dose-limiting toxicities were observed across all cohorts.
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RAD101 Phase 2b Primary Endpoint Met
In 30 patients with suspected recurrent brain metastases, RAD101 PET demonstrated 93% concordance with MRI across all evaluable lesions, meeting the trial's primary objective.
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RAD101 Sensitivity and Phase 3 Plans
Preliminary sensitivity reached 86% (12/14 patients) in a subset with six-month follow-up/biopsy data. A U.S. Phase 3 pivotal trial is planned to initiate in Q4 2026, targeting a $600M+ addressable market.
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Cash Runway Context
The positive data come after a recent A$5.9M R&D tax refund improved the cash position, but the company had only 1.29 quarters of cash as of April 2026, highlighting the need for these catalysts to support future financing.
Analysis · RADX · Life Sciences
Two significant clinical milestones were announced by Radiopharm Theranostics: a confirmed durable Partial Response in the Phase 1 trial of RAD204, its PD-L1-targeted radiotherapeutic, and positive Phase 2b results for RAD101, a diagnostic imaging agent for brain metastases. The RAD204 data show a patient remaining progression-free beyond seven months with no dose-limiting toxicities, supporting dose escalation and a planned Phase 2 trial. Meeting its primary endpoint, the RAD101 trial demonstrated 93% concordance versus MRI, and preliminary sensitivity of 86% in a subset of patients, paving the way for a pivotal Phase 3 trial in Q4 2026. These results validate the company's radiopharmaceutical platform and address significant unmet needs in oncology, potentially transforming the investment thesis for this micro-cap biotech.
At the time of this filing, RADX was trading at $4.60 on NASDAQ in the Life Sciences sector, with a market capitalization of approximately $47.1M. The 52-week trading range was $3.62 to $16.25. This filing was assessed with positive market sentiment and an importance score of 9 out of 10.