Immutep’s Efti with Radiotherapy & KEYTRUDA® (pembrolizumab) Meets Primary Endpoint in Phase II for Soft Tissue Sarcoma
Immutep (NASDAQ: IMMP) has announced positive results from its Phase II EFTISARC-NEO trial, evaluating eftilagimod alfa (efti) in combination with radiotherapy and KEYTRUDA® for resectable soft tissue sarcoma (STS). The trial met its primary endpoint, achieving significantly higher tumor hyalinization/fibrosis rates compared to historical data. The combination therapy demonstrated 50% tumor hyalinization/fibrosis in preliminary analysis, substantially exceeding the prespecified target of 35% and historical radiotherapy-alone data of 15%.
The study, conducted at Poland's national STS reference center, completed enrollment of 40 patients in January 2025. This chemotherapy-free treatment represents a potential breakthrough for STS, an orphan disease with poor prognosis affecting approximately 13,520 new cases in the US in 2025, with an estimated 5,420 deaths.
Immutep (NASDAQ: IMMP) ha annunciato risultati positivi dal suo trial di Fase II EFTISARC-NEO, che valuta eftilagimod alfa (efti) in combinazione con radioterapia e KEYTRUDA® per il sarcoma dei tessuti molli (STS) resecabile. Lo studio ha raggiunto l'endpoint primario, ottenendo tassi significativamente più elevati di ialinizzazione/fibrosi tumorale rispetto ai dati storici. La terapia combinata ha mostrato una ialinizzazione/fibrosi tumorale del 50% nell'analisi preliminare, superando ampiamente l'obiettivo prefissato del 35% e i dati storici della sola radioterapia del 15%.
Lo studio, condotto presso il centro nazionale di riferimento per STS in Polonia, ha completato il reclutamento di 40 pazienti a gennaio 2025. Questo trattamento senza chemioterapia rappresenta una potenziale svolta per il STS, una malattia rara con prognosi sfavorevole che colpisce circa 13.520 nuovi casi negli Stati Uniti nel 2025, con una stima di 5.420 decessi.
Immutep (NASDAQ: IMMP) ha anunciado resultados positivos de su ensayo de Fase II EFTISARC-NEO, que evalúa eftilagimod alfa (efti) en combinación con radioterapia y KEYTRUDA® para el sarcoma de tejidos blandos (STS) resecable. El ensayo cumplió su objetivo principal, logrando tasas significativamente más altas de hialinización/fibrosis tumoral en comparación con datos históricos. La terapia combinada demostró una hialinización/fibrosis tumoral del 50% en el análisis preliminar, superando ampliamente el objetivo preestablecido del 35% y los datos históricos de radioterapia sola del 15%.
El estudio, realizado en el centro nacional de referencia para STS en Polonia, completó la inscripción de 40 pacientes en enero de 2025. Este tratamiento sin quimioterapia representa un posible avance para el STS, una enfermedad rara con pronóstico desfavorable que afecta aproximadamente a 13,520 nuevos casos en EE. UU. en 2025, con una estimación de 5,420 muertes.
Immutep (NASDAQ: IMMP)는 절제 가능한 연부조직 육종(STS)에 대해 방사선 치료 및 KEYTRUDA®와 병용한 eftilagimod alfa(efti)의 효과를 평가한 2상 EFTISARC-NEO 시험에서 긍정적인 결과를 발표했습니다. 이 임상시험은 1차 평가변수를 충족했으며, 과거 데이터와 비교해 종양 유리화/섬유화 비율이 유의하게 높았습니다. 병용요법은 예비 분석에서 50%의 종양 유리화/섬유화를 보여, 사전 설정 목표인 35%와 방사선 치료 단독의 과거 데이터 15%를 크게 초과했습니다.
폴란드 국립 STS 참조 센터에서 진행된 이 연구는 2025년 1월에 40명의 환자 등록을 완료했습니다. 이 화학요법 없는 치료법은 예후가 좋지 않은 희귀질환인 STS에 있어 잠재적인 혁신적 치료법으로, 2025년 미국에서 약 13,520건의 신규 환자와 약 5,420명의 사망자가 발생할 것으로 추정됩니다.
Immutep (NASDAQ : IMMP) a annoncé des résultats positifs issus de son essai de phase II EFTISARC-NEO, évaluant eftilagimod alfa (efti) en combinaison avec la radiothérapie et KEYTRUDA® pour le sarcome des tissus mous (STS) résécable. L'essai a atteint son critère principal, obtenant des taux significativement plus élevés d'hyalinisation/fibrose tumorale comparés aux données historiques. La thérapie combinée a démontré une hyalinisation/fibrose tumorale de 50% lors de l'analyse préliminaire, dépassant largement l'objectif prédéfini de 35% ainsi que les données historiques de la radiothérapie seule à 15%.
Cette étude, menée au centre national de référence STS en Pologne, a terminé le recrutement de 40 patients en janvier 2025. Ce traitement sans chimiothérapie représente une avancée potentielle pour le STS, une maladie orpheline au pronostic défavorable touchant environ 13 520 nouveaux cas aux États-Unis en 2025, avec environ 5 420 décès estimés.
Immutep (NASDAQ: IMMP) hat positive Ergebnisse aus seiner Phase-II-Studie EFTISARC-NEO bekannt gegeben, die eftilagimod alfa (efti) in Kombination mit Radiotherapie und KEYTRUDA® bei resezierbarem Weichteilsarkom (STS) untersucht. Die Studie erreichte ihren primären Endpunkt und erzielte signifikant höhere Raten an Tumor-Hyalinisierung/Fibrose im Vergleich zu historischen Daten. Die Kombinationstherapie zeigte in der vorläufigen Analyse eine 50%ige Tumor-Hyalinisierung/Fibrose, was das vorgegebene Ziel von 35% sowie die historischen Daten der alleinigen Radiotherapie von 15% deutlich übertraf.
Die Studie, durchgeführt am nationalen STS-Referenzzentrum in Polen, schloss im Januar 2025 die Einschreibung von 40 Patienten ab. Diese chemotherapiefreie Behandlung stellt einen potenziellen Durchbruch für STS dar, eine seltene Erkrankung mit schlechter Prognose, die in den USA im Jahr 2025 etwa 13.520 Neuerkrankungen und geschätzte 5.420 Todesfälle verursacht.
- Trial met primary endpoint with 50% tumor hyalinization/fibrosis vs 15% historical data
- Chemotherapy-free combination therapy shows strong anti-cancer efficacy
- Study completed enrollment of 40 patients, exceeding initial analysis of 21 patients
- Results suggest potential improvement in overall survival and recurrence-free survival
- Detailed results not yet available, pending future medical meeting presentation
- Study limited to resectable soft tissue sarcoma patients only
Insights
Immutep's triple combination therapy shows promising efficacy in soft tissue sarcoma, meeting primary endpoint with significantly better tumor response than historical controls.
The EFTISARC-NEO Phase II trial results represent a significant clinical achievement for Immutep's eftilagimod alfa (efti). The combination of efti with radiotherapy and pembrolizumab demonstrated remarkable efficacy by exceeding the prespecified median of
What's particularly noteworthy is that a preliminary analysis showed a median of
The chemotherapy-free approach is especially valuable in STS treatment, where conventional chemotherapy regimens often have limited efficacy and significant toxicity. Efti's mechanism of activating antigen-presenting cells to transform the immunosuppressed tumor microenvironment addresses a fundamental challenge in sarcoma treatment - these tumors are typically immunologically "cold" and resistant to immunotherapy alone.
Soft tissue sarcoma represents a high unmet medical need with approximately 13,520 new cases and 5,420 deaths expected in the US in 2025. As an orphan disease with poor prognosis, any advancement in treatment is significant for this patient population that has seen limited therapeutic innovations. The study's completion of enrollment (40 patients) in January 2025 indicates robust interest in this novel approach.
- Novel combination with efti has met the trial’s primary endpoint of tumour hyalinization/fibrosis in the neoadjuvant setting for patients with resectable soft tissue sarcoma
- Detailed results are planned for presentation at a future medical meeting
SYDNEY, AUSTRALIA, May 27, 2025 (GLOBE NEWSWIRE) -- Immutep Limited (ASX: IMM; NASDAQ: IMMP) (“Immutep” or “the Company”), a late-stage immunotherapy company targeting cancer and autoimmune diseases, today announces the investigator-initiated EFTISARC-NEO Phase II trial evaluating eftilagimod alfa (efti) with radiotherapy plus KEYTRUDA® (pembrolizumab) in the neoadjuvant setting for resectable soft tissue sarcoma (STS) has met its primary endpoint. The novel combination significantly exceeded the study’s prespecified median of
Tumour hyalinization/fibrosis is an early surrogate endpoint at the time of surgical resection that has been associated with improved overall survival and recurrence-free survival for STS patients.1,2 The trial’s investigators at the Maria Skłodowska-Curie National Research Institute of Oncology (MSCNRIO) in Warsaw, the national reference centre for STS in Poland, plan to present detailed results from the study at a future medical meeting.
Katarzyna Kozak, M.D., Ph.D., and Paweł Sobczuk, M.D., Ph.D., medical oncologists at the Department of Soft Tissue/Bone Sarcoma and Melanoma at MSCNRIO and the trial’s principal investigators, said: “It is very encouraging to see the chemotherapy-free combination with efti far exceed the ambitious target we initially set for the trial's primary endpoint in resectable soft tissue sarcoma. These results support our belief that efti's activation of antigen-presenting cells, and in turn a broad adaptive and innate immune response, helps transform the immunosuppressed tumour microenvironment of soft tissue sarcomas leading to strong anti-cancer efficacy. There remains a very high unmet need in this aggressive orphan cancer indication and we look forward to presenting detailed results at a medical meeting later this year.”
As previously announced at the Connective Tissue Oncology Society (CTOS) Annual Meeting in November 2024, the combination therapy demonstrated significant efficacy with a median of
STS is an orphan disease with high unmet medical need and a poor prognosis for patients. The incidence of STS varies in different regions globally. In the United States, the number of new STS cases in 2025 is estimated to be ~13,520 with ~5,420 deaths, according to the American Cancer Society.3
For more information on EFTISARC-NEO, visit clinicaltrials.gov (NCT06128863).
About Eftilagimod Alfa (efti)
Efti is Immutep’s proprietary soluble LAG-3 protein and MHC Class II agonist that stimulates both innate and adaptive immunity for the treatment of cancer. As a first-in-class antigen presenting cell (APC) activator, efti binds to MHC (major histocompatibility complex) Class II molecules on APC leading to activation and proliferation of CD8+ cytotoxic T cells, CD4+ helper T cells, dendritic cells, NK cells, and monocytes. It also upregulates the expression of key biological molecules like IFN-ƴ and CXCL10 that further boost the immune system’s ability to fight cancer.
Efti is under evaluation for a variety of solid tumours including non-small cell lung cancer (NSCLC), head and neck squamous cell carcinoma (HNSCC), and metastatic breast cancer. Its favourable safety profile enables various combinations, including with anti-PD-[L]1 immunotherapy and/or chemotherapy. Efti has received Fast Track designation in first line HNSCC and in first line NSCLC from the United States Food and Drug Administration (FDA).
About Immutep
Immutep is a late-stage biotechnology company developing novel immunotherapies for cancer and autoimmune disease. The Company is a pioneer in the understanding and advancement of therapeutics related to Lymphocyte Activation Gene-3 (LAG-3), and its diversified product portfolio harnesses LAG-3’s ability to stimulate or suppress the immune response. Immutep is dedicated to leveraging its expertise to bring innovative treatment options to patients in need and to maximise value for shareholders. For more information, please visit www.immutep.com.
1. Schaefer IM et al. Histologic Appearance After Preoperative Radiation Therapy for Soft Tissue Sarcoma: Assessment of the European Organization for Research and Treatment of Cancer-Soft Tissue and Bone Sarcoma Group Response Score. Int J Radiat Oncol Biol Phys. 2017 Jun 1;98(2):375-383. doi: 10.1016/j.ijrobp.2017.02.087. Epub 2017 Feb 24. PMID: 28463157.
2. Rao SR et al. Extent of tumor fibrosis/hyalinization and infarction following neoadjuvant radiation therapy is associated with improved survival in patients with soft-tissue sarcoma. Cancer Med. 2022 Jan;11(1):194-206. doi: 10.1002/cam4.4428. Epub 2021 Nov 27. PMID: 34837341; PMCID: PMC8704179.
3. American Cancer Society statistics: https://www.cancer.org/cancer/types/soft-tissue-sarcoma/about/key-statistics.html
KEYTRUDA® is a registered trademark of Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA.
Australian Investors/Media:
Catherine Strong, Sodali & Co.
+61 (0)406 759 268; catherine.strong@sodali.com
U.S. Media:
Chris Basta, VP, Investor Relations and Corporate Communications
+1 (631) 318 4000; chris.basta@immutep.com
FAQ
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