Sanofi and partners have announced positive results from their Phase 2 study evaluating the efficacy and safety of AlphaMedix (Pb-DOTAMTATE) in patients with histologically confirmed unresectable or metastatic gastroenteropancreatic neuroendocrine tumours (GEP-NETs), positive somatostatin analogue imaging, and at least one measurable disease site.

Developed by Orano Med and RadioMedix and now licensed to Sanofi, the investigational somatostatin receptor (SSTR)-targeted alpha therapy, which uses the lead-212 isotope, met all primary efficacy endpoints, demonstrating clinically meaningful overall response rates (ORR) and prolonged clinical benefits in both peptide receptor radionuclide therapy (PRRT)-naïve and PRRT-exposed patients.

Significant improvements in key secondary endpoints, including progression-free survival (PFS) and overall survival (OS), were also observed across both patient cohorts. AlphaMedix exhibited a manageable safety profile, which was consistent between groups.

"The positive results from the ALPHAMEDIX-02 study represent a pivotal movement for the Orano Med 212Pb-based platform and underscore the profound potential of lead-212-based radiopharmaceuticals in addressing critical unmet needs for patients with GEP-NETs,” said Volker Wagner, Chief Medical Officer at Orano Med.  

“These data reinforce our belief that delivering highly potent alpha-emitters directly to cancer cells could potentially offer a meaningful new treatment option for people living with GEP-NETs,” he added.

Alpha-emitters are being investigated for their ability to deliver potent, targeted tumour activity while potentially reducing damage to surrounding healthy tissues due to the short range of alpha particles.

In February 2024, AlphaMedix received Breakthrough Therapy Designation from the US FDA for the treatment of PRRT-naïve patients with unresectable or metastatic, progressive, SSTR-expressing GEP-NETs, recognising its potential clinical benefit and innovative mechanism.

In September 2024, Orano Med and RadioMedix entered into an exclusive licensing agreement with Sanofi for AlphaMedix. Under this agreement, Sanofi assumes global responsibility for the commercialisation of the therapy.

"The promising ALPHAMEDIX-02 results represent a significant step forward, reinforcing the potential of targeted alpha therapy to deliver precise treatment for GEP-NETs. We look forward to advancing AlphaMedix and working with Orano Med and regulators to bring this important treatment to the GEP-NET community as soon as possible,” said Christopher Corsico, Global Head of Development at Sanofi.

The Phase 2 study remains ongoing, and full results will be presented at the 2025 European Society for Medical Oncology (ESMO) Congress, the companies said.