Novel transforming growth factor beta receptor I kinase inhibitor galunisertib (LY2157299) in advanced hepatocellular carcinoma

Background and aims: We assessed the activity of galunisertib, a small molecule inhibitor of the transforming growth factor beta (TGF-β1) receptor I, in second-line patients with hepatocellular carcinoma (HCC) in two cohorts of baseline serum alpha fetoprotein (AFP).

Methods: Patients with advanced HCC who progressed on or were ineligible to receive sorafenib, Child-Pugh A/B7 and ECOG PS ≤1 were enrolled into Part A (AFP ≥ 1.5× ULN) or Part B (AFP < 1.5× ULN). Patients were treated with 80 or 150 mg galunisertib BID for 14 days per 28-day cycle. Endpoints were time-to-progression (TTP) and changes in circulating AFP and TGF-β1 levels, as well as safety, pharmacokinetics, progression-free survival and overall survival (OS).

Results: Patients (n = 149) were enrolled with median age 65 years. Median TTP was 2.7 months (95% CI: 1.5-2.9) in Part A (n = 109) and 4.2 months (95% CI: 1.7-5.5) in Part B (n = 40). Median OS was 7.3 months (95% CI: 4.9-10.5) in Part A and 16.8 months (95% CI: 10.5-24.4) in Part B. OS was longer in AFP responders (>20% decrease from baseline, Part A) compared to non-responders (21.5 months vs 6.8 months). OS was longer in TGF-β1 responders (>20% decrease from baseline, all patients) compared to non-responders. The most common Grade 3/4 treatment-related adverse events were neutropenia (n = 4) and fatigue, anaemia, increased bilirubin, hypoalbuminemia and embolism (each, n = 2).

Conclusions: Galunisertib treatment had a manageable safety profile in patients with HCC. Lower baseline AFP and a response in AFP or TGF-β1 levels (vs no response) correlated with longer survival.

Trial registration number: NCT01246986 at ClinicalTrials.gov.