Idera Pharmaceuticals has commenced a Phase III trial examining intratumoral IMO-2125 in combination with ipilimumab (Yervoy) in the treatment of patients with anti-PD-1 refractory melanoma.

The efficacy and safety of the combination treatment will be trialled in comparison with ipilimumab given alone to patients.

IMO-2125 is designed to activate the immune system’s creation of cancer-fighting cells (T-cells), which target solid tumours in refractory melanoma patients. The designation is intended to accelerate the development and review of drugs with the potential to treat serious or life-threatening conditions such as refractory metastatic melanoma.

The multi-centre, open-label Illuminate 301 trial is expected to be conducted in around 80 sites across ten countries. It aims to enrol roughly 300 patients with advanced melanoma who have confirmed disease progression while on nivolumab (Opdivo) or pembrolizumab (Keytruda). Participants need to have histologically confirmed metastatic melanoma with measurable or Stage IVA, IVB, or IVC disease, and at least one lesion that is accessible for injection.

In the trial, patients will be randomised into two treatment arms; IMO-2125 in combination with ipilimumab and ipilimumab monotherapy. The trial will be carried out to provide definitive evidence for superiority of the IMO-2125 and ipilimumab combination over ipilimumab.

“This Phase 3 trial offers hope to this large group of patients whose treatment options are very limited.”

Clinic Taussig Cancer Institute’s melanoma and skin cancer programme director Dr Ahmad Tarhini said:  “I am encouraged by the data that has been demonstrated to date with IMO-2125 and am hopeful that this Phase 3 trial offers hope to this large group of patients whose treatment options are very limited.”

The reported overall response rate for ipilimumab monotherapy following anti-PD-1 therapy is 13%, while the primary objective of the trial includes overall survival and overall response rate.

Findings from the completed Phase I portion of an ongoing Phase I/II clinical trial of intratumoral IMO-2125 in combination with ipilimumab have demonstrated that the combination is well-tolerated over the entire range of IMO 2125 doses tested.

Idera CMO Joanna Horobin said: “We are excited to initiate the ILLUMINATE 301 Trial, grateful to our advisers who have worked with us to design this pivotal trial and very encouraged by the enthusiasm of investigators to participate in the study.  We look forward to working together to conduct and complete this trial, so that we may bring IMO-2125 to the market as soon as possible for patients who are not benefiting from anti-PD-1 therapy.” 

Idera Pharmaceuticals noted that its IMO-2125 received a fast-track designation from the US Food and Drug Administration.