In the controlled Phase 2 clinical trial, SCCHN patients were treated either with IMO-2055 at a dose of 0.32mg/kg given subcutaneously once weekly in combination with weekly cetuximab, or with cetuximab alone.
The study’s primary endpoint was progression-free survival, while the secondary outcome measures included overall response rate (by RECIST), disease control rate, overall survival, and safety and tolerability.
The study did not meet its primary endpoint following treatment with IMO-2055 along with cetuximab compared to treatment with cetuximab alone.
As per the investigator assessments, the median progression-free survival was 2.9 months in both arms, and based on the independent radiology review, it was 1.9 months in the cetuximab arm and 1.5 months in the combination arm.
Idera Pharmaceuticals chairman and chief executive officer Sudhir Agrawal said the company is disappointed with the results of the trial, considering the favorable results reported earlier this year from a single-arm Phase 1b study of IMO-2055 in combination with Tarceva and Avastin in patients with non-small cell lung cancer as well as the safety profile of IMO-2055 in combination with targeted anti-cancer agents that has been observed in multiple clinical trials.
"We believe that IMO-2055 may have clinical and commercial potential for certain cancer indications and plan to seek to advance IMO-2055 through collaborations with third parties," Agrawal added.