ITM's Radiotherapy Shows Promise in Phase 3 Trial, Despite Overall Survival Miss

ITM Isotope Technologies has unveiled detailed results from a pivotal phase 3 study of its lead radiotherapy candidate, ITM-11, in patients with somatostatin receptor (SSTR)-positive neuroendocrine tumors of the stomach or pancreas. The trial, which compared ITM-11 to the standard of care everolimus, demonstrated significant improvements in progression-free survival (PFS) but fell short on the overall survival (OS) endpoint.

Progression-Free Survival Benefit

The phase 3 study, involving 309 patients, revealed that ITM-11 significantly extended median PFS to 23.9 months, compared to 14.1 months observed in the everolimus group. This marked improvement in PFS represents a substantial advancement in the treatment of SSTR-positive neuroendocrine tumors, potentially offering patients a more effective therapeutic option.

Overall Survival and Safety Profile

Despite the PFS success, ITM-11 did not achieve a statistically significant benefit in median overall survival. The ITM-11 cohort reached 63.4 months, while the everolimus group achieved 58.7 months. ITM attributed this lack of statistical significance to the study design, which allowed patients to start alternative therapies after disease progression, potentially confounding the OS data.

In terms of safety, ITM-11 demonstrated a favorable profile compared to everolimus. Treatment-emergent adverse events were reported in 82.5% of patients receiving ITM-11, versus 97% in the everolimus group. However, one grade 2 serious event of myelodysplastic syndrome was reported as related to ITM-11.

Implications for ITM and Future Directions

Dr. Andrew Cavey, CEO of ITM, emphasized the significance of these results, stating, "These successful results validate our decision to design a pivotal phase 3 trial directly comparing a targeted radiopharmaceutical against a targeted molecular therapy ... underscoring our commitment to improving the lives of people living with this challenging cancer."

The positive outcome of this trial marks a crucial milestone for ITM, as ITM-11 becomes the company's first drug candidate to deliver positive phase 3 results. This achievement paves the way for New Drug Application (NDA) submission and commercial launch preparations, potentially expanding treatment options for patients with neuroendocrine tumors.

ITM continues to advance its radiopharmaceutical portfolio, with ongoing trials including a phase 1 study in children with SSTR-positive tumors and a phase 3 study in lung and thymus neuroendocrine tumors. These developments underscore ITM's commitment to leveraging its two decades of radioisotope expertise to bring innovative therapies to market.