German-based biotech firm Mologen has reported positive first combination data of its TLR9 agonist lefitolimod with checkpoint inhibitors in preclinical tumour models.
Lefitolimod is a TLR9 agonist designed to trigger immune system by reactivating its monitoring function.
The drug is being developed for the treatment of first-line maintenance treatment of colorectal cancer and small-cell lung cancer and has been recognised as Immune Surveillance Reactivator (ISR) due to its mechanism of action.
The combination data indicated that in murine tumour models, lefitolimod could increase the anti-tumour effect of checkpoint inhibitors such as anti-PD-1 and anti-PD-L1 antibodies.
The in-vitro experiments conducted further confirmed the positive effect of the combination of lefitolimod with anti-PD-1, when compared to each monotherapeutic approach.
Mologen chief executive officer Mariola Söhngen said: “We believe that patients can benefit from the combination of these immunotherapies due to their modes of action complementing each other.
"The new results are an important proof-of-concept for the combination approach of lefitolimod with checkpoint inhibitors.
"Consequently, the data opens further application possibilities for our lead product and supports our ongoing phase I combination study of lefitolimod with the checkpoint inhibitor Yervoy. ”
The clinical trial to evaluate the combination therapy will be conducted in approximately 50-60 patients by MD Anderson Cancer Center, Texas, US, for which Mologen will offer funding and the ISR lefitolimod.
The trail will intially evaluate the best tolerable dose and safety of lefitolimod in combination with Yervoy, with plans for an expansion phase to assess the efficacy of the combination.
Patient enrolment commenced last July and is expected to be completed by the beginning of 2018.