Immutep Reports Encouraging EFTISARC-NEO Phase II Sarcoma Survival Data; Efti + KEYTRUDA + Radiotherapy Shows 81.1% 12-Month DFS, 94.1% LRFS And 86.2% DMFS In 38 Patients

• First survival data from EFTISARC-NEO, released in CTOS 2026 Abstract, demonstrate encouraging preliminary long-term outcomes in patients with resectable soft tissue sarcoma (STS).
• With a median follow-up of 19.1 months, 12-month disease-free survival (DFS), local recurrence-free survival (LRFS) and distant metastasis-free survival (DMFS) rates were 81.1%, 94.1% and 86.2%, respectively, in 38 evaluable patients.
• Investigators conclude that efti plus KEYTRUDA® (pembrolizumab) and radiotherapy as neoadjuvant therapy showed promising preliminary long-term outcomes warranting registrationally relevant trials in patients with STS.
• Further and new analyses will be presented in a poster discussion session on 19 November 2026 and will be the subject of a further announcement by the Company.
  
  
  
   

SYDNEY, AUSTRALIA, Nov. 11, 2026 (GLOBE NEWSWIRE) -- Immutep Limited ((ASX: IMM, NASDAQ:IMMP) today announced the release of an abstract reporting interim disease-free survival data and clinicopathological correlates from EFTISARC-NEO, the investigator-initiated Phase II trial of eftilagimod alfa (efti) plus KEYTRUDA® (pembrolizumab) and radiotherapy as neoadjuvant treatment for resectable soft tissue sarcoma (STS). Further detail and analyses will be presented in a poster discussion session on 19 November 2026 at the Connective Tissue Oncology Society (CTOS) 2026 Annual Meeting, being held from 18–21 November 2026 in Seoul, South Korea.

As reported in October 2025, EFTISARC-NEO has met its primary endpoint, with a median tumour hyalinisation/fibrosis of 51.5% in 38 evaluable patients, well above the pre-specified target of 35% and approximately 15% historically observed with radiotherapy alone.1 Health-related quality of life data presented at the ESMO Congress 2026 in October showed no significant deterioration during treatment and a statistically significant improvement following surgery. The U.S. Food and Drug Administration granted Orphan Drug Designation to efti for the treatment of STS in April 2026. The survival outcomes reported here are secondary endpoints of the trial.

With a median follow-up of 19.1 months, the 12-month disease-free survival (DFS), local recurrence-free survival (LRFS) and distant metastasis-free survival (DMFS) rates were 81.1%, 94.1% and 86.2%, respectively, in 38 evaluable patients (data cut-off 30 April 2026). No differences in DFS were observed across tumour grade, stage or histological subtype.

The investigators concluded that efti plus pembrolizumab on top of standard radiotherapy as neoadjuvant therapy showed promising preliminary long-term outcomes warranting registrationally relevant trials in patients with STS. The investigators reported that high infiltration by tumour-infiltrating lymphocytes (TIL) and tumour hyalinisation/fibrosis after therapy may be associated with better DFS but that longer follow-up is necessary.

Follow-up for DFS and overall survival is ongoing.

For further details see the Events section of Immutep’s website. The poster with updated data will be made available on the Posters & Publications page of Immutep’s website at www.immutep.com following its presentation at the meeting.