Immutep Limited’s Phase II EFTISARC-NEO trial reveals a novel immunotherapy combo delivering a striking 51.5% tumour response in soft tissue sarcoma patients, alongside robust immune activation signals.
- 51.5% median tumour hyalinization/fibrosis achieved with efti, radiotherapy, and KEYTRUDA
- Strong immune activation evidenced by significant rises in cytokines and chemokines
- Efficacy observed across 10 soft tissue sarcoma subtypes, including rare aggressive forms
- Early biomarker increases correlate with improved pathological responses
- EFTISARC-NEO awarded Poland’s prestigious Golden Scalpel for medical innovation
A Breakthrough in Soft Tissue Sarcoma Treatment
Immutep Limited, a biotechnology company focused on immunotherapy, has unveiled compelling data from its Phase II EFTISARC-NEO trial, spotlighting a novel neoadjuvant treatment approach for soft tissue sarcoma (STS). The combination of eftilagimod alfa (efti), radiotherapy, and KEYTRUDA (pembrolizumab) achieved a median 51.5% tumour hyalinization and fibrosis rate, a marker of significant tumour destruction. This result notably surpasses historical benchmarks for radiotherapy alone, suggesting a meaningful advance in managing this challenging cancer type.
Immune System Activation at the Forefront
Beyond tumour shrinkage, the trial’s translational data reveal a robust immune response consistent with efti’s mechanism of action. Patients exhibited statistically significant increases in key immune proteins such as interferon-gamma (IFN-γ), CXCL9, CXCL10, and IL-23. These cytokines and chemokines are critical in orchestrating the body’s adaptive and innate immune defenses, indicating that the therapy not only attacks the tumour directly but also mobilizes the immune system to sustain the fight.
Diverse and Difficult Tumour Subtypes Respond
The trial included 38 evaluable patients spanning ten STS subtypes, including notoriously aggressive and rare forms like myxofibrosarcoma and malignant peripheral nerve sheath tumour. The broad efficacy across these subtypes underscores efti’s potential versatility and may open new avenues for treating patients with limited options and poor prognoses.
Clinical and Regulatory Implications
While survival data remain immature, the high tumour response rate and immune biomarker correlations are promising early surrogate endpoints linked to better long-term outcomes. The findings bolster the rationale for advancing efti combinations into registrational trials, potentially expanding its use into earlier-stage cancers where tumour burden is lower. Immutep’s Chief Scientific Officer highlighted the therapy’s favorable safety profile and its capacity to synergize with existing treatments, positioning it well in the evolving immuno-oncology landscape.
Recognition and Next Steps
The EFTISARC-NEO trial’s innovation was recognized with Poland’s Golden Scalpel Award, a testament to its clinical impact and research excellence. As the company prepares to present further survival and translational data, investors and clinicians alike will be watching closely to see if these early signals translate into durable patient benefits and regulatory approvals.
Bottom Line?
EFTISARC-NEO’s promising tumour and immune response data set the stage for pivotal trials that could redefine soft tissue sarcoma treatment.
Questions in the middle?
- Will forthcoming survival data confirm the early surrogate markers’ predictive value?
- How will efti’s safety and efficacy profile compare in larger, registrational studies?
- Can this immunotherapy combo extend to other solid tumours beyond soft tissue sarcoma?