Researchers are seeking prognostic biomarkers for response to treatment with adjuvant sorafenib (Nexavar) in patients with hepatocellular carcinoma, according to a presentation during the 2017 International Liver Cancer Association Annual Conference in Seoul, South Korea.
1,2In an analysis of the phase III STORM trial, 2 biomarkers were found that were indicative of patients’ responses; however, no predictive biomarkers were found to identify patients with a greater risk for recurrence following sorafenib.
The STORM trial demonstrated no significant difference in recurrence-free survival (RFS), time to recurrence, and overall survival for patients being treated with adjuvant sorafenib versus placebo. However, due to the adjuvant trial design, tissue samples were evaluated for biomarker analysis aimed at determining the molecular prognostic factors and predictors of recurrence with sorafenib.
Overall, no biomarkers related to angiogenesis, proliferation, previously proposed gene signatures, or mutations were independently associated with recurrence or prevention for treatment with sorafenib. Recurrence often occurs after resection in 70% of patients at 5 years, according to Robert Montal, MD, a visiting researcher at Mount Sinai Health System.
“The idea of the companion biomarker clinical trial was to infer molecular alterations that could discriminate [between] the subpopulation of patients who could benefit from sorafenib in the adjuvant setting,” said Montal in an interview withTargeted Therapies in Oncology™.
The STORM trial collected tumor samples from 188 patients with resected HCC, 83 of which were treated with sorafenib, and 105 patients with placebo. Prognostic and predictive biomarkers were analyzed by gene expression, targeted exome sequencing of 18 mutational drivers, assessment of activation of MAPK signaling, and angiogenesis.
Positive hepatocyte pERK staining (hazard ratio [HR], 2.41; 95% CI, 1.21-4.8; P = .012) and microvascular invasion were independent prognostic factors in regard to predictive variables for RFS. In the STORM trial, RFS events (recurrences) occurred in 70 cases.
There was an association found between hepatocyte pERK-positive and proliferation gene signatures (P <.001), poor differentiation (P = .01), and Ki-67 positivity (P <.05).
The STORM trial did not identify candidate biomarkers predicting recurrence prevention with sorafenib. Biomarkers related to angiogenesis, proliferation, previously proposed gene signatures, or mutations were not independently associated with recurrence or prevention with sorafenib.
However, the investigators generated a multigene signature that did correlate with improved RFS with sorafenib versus placebo, but this would require external validation.
“None of the prespecified biomarkers obtained the statistically significant results in terms of the prediction of benefit to sorafenib,” Montal explained. “We designed a gene signature composed of 146 genes that are able to identify those patients in our cohort who benefit from sorafenib, but certainly, these gene signatures should be externally evaluated for assessing its clinical validity.”
Questions remain in determining how to incorporate biomarkers into clinical practice for HCC, especially when using them to identify patients who would best respond to current and emerging therapies.
“In HCC, and similar to other solid tumors, these predictive biomarkers have not been incorporated yet in the clinical practice. In fact, most of the phase III trials assessing new drugs in HCC have failed targeting all-comers. The idea would be to start the development of new drugs in HCC together with the predictive biomarkers from the further stems of the clinical research,” said Montal.
Another area of increasing interest regarding biomarkers for HCC is the development and optimization of liquid biopsies to help determine the biology of tumors. Additionally, the survival benefit shown with systemic therapies in phase III trials, with sorafenib, regorafenib (Stivarga), and lenvatinib (Lenvima), is continuing to be investigated. Immune checkpoint inhibitors are also being studied in HCC as they have dramatically changed the standard of care in other solid tumors, most notably in nonsmall cell lung cancer, melanoma, and urothelial carcinoma. In liver cancer, the PD-1 inhibitor nivolumab (Opdivo) recently received an accelerated approval from the FDA for the treatment of patients with HCC following treatment with sorafenib.