As of July 2025, 62 patients have been treated with IKS014 across five dose levels (40, 60, 90, 120 and 105 mg/m2), including 10 patients with HER2+ oesophageal cancers. Encouraging anti-tumour activity was seen across all dose levels in patients with a variety of tumour indications such as breast, ovarian, gallbladder, lung and oesophageal cancers, and in patients with HER2+ and HER2 low tumours.
Of the sub-set of 10 patients with HER2+ oesophageal cancer, who had received prior therapy (median 3, range 1-6), five achieved a response, including a complete response in one patient with non-measurable disease, whilst three other patients demonstrated stable disease for more than six months, resulting in a clinical benefit rate for IKS014 of 80%. These positive results warrant further exploration, and the dose expansion part of this Phase 1 study will now include an additional expansion cohort specifically for patients with HER2-expressing oesophageal adenocarcinoma who have previously received at least one prior line of standard treatment that may have included a HER2-directed therapy.