Cancer Vaccine IMM-101 Plus Gemcitabine Shows Hopeful Results in Metastatic Pancreatic Cancer

About IMM-101

IMM-101 contains heat‐inactivated Mycobacterium obuense. Pre-clinical and clinical studies suggest IMM-101 can invoke an immune-modulatory response resulting in the release of cancer antigens, increased immune reactivity, decreased immunosuppression, and activation of immune cells known to have an anti-cancer effect.

“Only 18% of patients with advanced PDAC remain alive at one year, and 4% at five years […] Real-world studies report the median overall survival from diagnosis to be 4.6 months; in patients with metastatic cancer, the median survival ranges between 2.8 and 5.7 months.” said the authors.

On the choice for gemcitabine monotherapy as comparator arm, the authors commented that “Gemcitabine was the standard of care for advanced PDAC and at that time [of study start] it was widely used as the comparator arm in clinical trials for this disease.”

Study Design

110 adult patients with confirmed inoperable PDAC and at least one measurable lesions at a previously not irradiated site who had a WHO performance status (PS) 0–2 were randomised 2:1 in this open-label, phase II trial at 20 institutions in 5 European countries.

The study knew two pre-defined subgroups, 1) patients with metastatic disease; and 2) patients with locally advanced disease. Results of the latter subgroup were affected by small sample size, as only 16% of patients had locally advanced disease.

PFS Results

PFS favoured the combination IMM-101 plus gemcitabine in both the ITT and metastatic subgroup populations. In the ITT group, PFS for IMM-101 plus gemcitabine was 4.1 months vs. 2.4 months in the gemcitabine monotherapy arm (HR 0.58; 95% CI, 0.37-0.91; P=0.016).

In the metastatic subgroup, PFS was 4.4 months vs. 2.3 months favouring the IMM-101 combination arm over the gemcitabine monotherapy arm (HR 0.46; 95% CI, 0.28-0.75; P=0.001).

OS Results

In the overall, intent-to-treat (ITT) population, median OS was not significant with 6.7 months vs. 6.6 months for IMM-101 plus gemcitabine vs. gemcitabine respectively. It must be noted the hazard ratio (HR) numerically favoured the IMM-101 combination arm (HR=0.68; 95% CI, 0.44–1.04; P=0.074).