Feasibility of therapeutic drug monitoring of sorafenib in patients with liver or thyroid cancer.

INTRODUCTION: Sorafenib is a tyrosine-kinase inhibitor approved for the treatment of renal cell carcinoma, hepatocellular carcinoma, thyroid carcinoma, and desmoid fibromatosis. As high inter-individual variability exists in exposure, there is a scientific rationale to pursue therapeutic drug monitoring (TDM). We investigated the feasibility of TDM in patients on sorafenib and tried to identify sub-groups in whom pharmacokinetically (PK) guided-dosing might be of added value. METHODS: We included patients who started on sorafenib (between October 2017 and June 2020) at the recommended dose of 400 mg BID or with a step-up dosing schedule. Plasma trough levels (Ctrough) were measured at pre-specified time-points. Increasing the dose was advised if Ctrough was below the target of 3750 ng/mL and toxicity was manageable. RESULTS: A total of 150 samples from 36 patients were collected. Thirty patients (83 %) had a Ctrough below the prespecified target concentration at a certain time point during treatment. Toxicity from sorafenib hampered dosing according to target Ctrough in almost half of the patients. In 11 patients, dosing was adjusted based on Ctrough. In three patients, this resulted in an adequate Ctrough without additional toxicity four weeks after the dose increase. In the remaining eight patients, dose adjustment based on Ctrough did not result in a Ctrough above the target or caused excessive toxicity. CONCLUSIONS: TDM for sorafenib is not of added value in daily clinical practice. In most cases, toxicity restricts the possibility of dose escalations.

Improved survival prediction and comparison of prognostic models for patients with hepatocellular carcinoma treated with sorafenib.

BACKGROUND: The 'Prediction Of Survival in Advanced Sorafenib-treated HCC' (PROSASH) model addressed the heterogeneous survival of patients with hepatocellular carcinoma (HCC) treated with sorafenib in clinical trials but requires validation in daily clinical practice. This study aimed to validate, compare and optimize this model for survival prediction. METHODS: Patients treated with sorafenib for HCC at five tertiary European centres were retrospectively staged according to the PROSASH model. In addition, the optimized PROSASH-II model was developed using the data of four centres (training set) and tested in an independent dataset. These models for overall survival (OS) were then compared with existing prognostic models. RESULTS: The PROSASH model was validated in 445 patients, showing clear differences between the four risk groups (OS 16.9-4.6 months). A total of 920 patients (n = 615 in training set, n = 305 in validation set) were available to develop PROSASH-II. This optimized model incorporated fewer and less subjective parameters: the serum albumin, bilirubin and alpha-foetoprotein, and macrovascular invasion, extrahepatic spread and largest tumour size on imaging. Both PROSASH and PROSASH-II showed improved discrimination (C-index 0.62 and 0.63, respectively) compared with existing prognostic scores (C-index ≤0.59). CONCLUSIONS: In HCC patients treated with sorafenib, individualized prediction of survival and risk group stratification using baseline prognostic and predictive parameters with the PROSASH model was validated. The refined PROSASH-II model performed at least as good with fewer and more objective parameters. PROSASH-II can be used as a tool for tailored treatment of HCC in daily practice and to define pre-planned subgroups for future studies.

Are we SHARP enough? The importance of adequate patient selection in sorafenib treatment for hepatocellular carcinoma.

BACKGROUND: Upon FDA/EMEA registration for hepatocellular carcinoma (HCC), sorafenib received a broader therapeutic indication than the eligibility criteria of the landmark SHARP trial. This allowed treatment of SHARP non-eligible patients in daily clinical practice. AIM: To assess sorafenib efficacy and safety in SHARP eligible and non-eligible patients, and determine the validity of the current therapeutic indication as described by the FDA/EMEA. PATIENTS AND METHODS: Consecutive patients treated with sorafenib for advanced HCC at two Dutch tertiary referral centers between 2007 and 2016 were analyzed retrospectively. Primary outcome was overall survival (OS). Secondary outcomes were time to progression (TTP), response rate, adverse events and reasons for discontinuation. Outcomes were compared between SHARP eligible and non-eligible patients. RESULTS: One hundred and ninety-three of 257 (75%) patients were SHARP eligible. SHARP eligible patients (9.5 months, 95% CI 7.7-11.3) had a longer median OS than non-eligible patients (5.4 months, 95% CI 3.6-7.1) (log-rank p < .001). SHARP non-eligible patients were more often Child-Pugh B, had higher AST and ALT levels and developed more grade 3-4 liver dysfunction (44 versus 23%, p < .001) during treatment. SHARP ineligibility remained the strongest predictor of OS (HR 1.78, 95% CI 1.32-2.41) and an independent predictor of TTP (HR 1.45, 95% CI 1.05-2.00) in multivariable analysis. CONCLUSIONS: Landmark trial outcomes of sorafenib for HCC are reproducible in daily practice, provided that the SHARP eligibility criteria are respected. Based on the findings of this and previous studies, sorafenib usage should be restricted to Child-Pugh A patients.

Linifanib versus Sorafenib in patients with advanced hepatocellular carcinoma: results of a randomized phase III trial.

PURPOSE: This open-label phase III trial evaluated efficacy and tolerability of linifanib versus sorafenib in patients with advanced hepatocellular carcinoma (HCC) without prior systemic therapy. PATIENTS AND METHODS: Patients were randomly assigned in a 1:1 ratio to linifanib 17.5 mg once daily or sorafenib 400 mg twice daily. Patients were stratified by region (Outside Asia, Japan, and rest of Asia), Eastern Cooperative Oncology Group performance score (ECOG PS; 0 or 1), vascular invasion or extrahepatic spread (yes or no), and hepatitis B virus (HBV) infection (yes or no). The primary end point of the study was overall survival (OS). Secondary end points were time to progression (TTP) and objective response rate (ORR) per RECIST v1.1. RESULTS: We randomly assigned 1,035 patients (median age, 60 years; Asian, 66.6%; ECOG PS 0, 65.2%; HBV, 49.1%; vascular invasion or extrahepatic spread, 70.1%). Median OS was 9.1 months on the linifanib arm (95% CI, 8.1 to 10.2) and 9.8 months on the sorafenib arm (95% CI, 8.3 to 11.0; hazard ratio [HR], 1.046; 95% CI, 0.896 to 1.221). For prespecified stratification subgroups, OS HRs ranged from 0.793 to 1.119 and the 95% CI contained 1.0. Median TTP was 5.4 months on the linifanib arm (95% CI, 4.2 to 5.6) and 4.0 months on the sorafenib arm (95% CI, 2.8 to 4.2; HR, 0.759; 95% CI, 0.643 to 0.895; P = .001). Best response rate was 13.0% on the linifanib arm versus 6.9% on the sorafenib arm. Grade 3/4 adverse events (AEs); serious AEs; and AEs leading to discontinuation, dose interruption, and reduction were more frequent with linifanib (all P < .001). CONCLUSION: Linifanib and sorafenib had similar OS in advanced HCC. Predefined superiority and noninferiority OS boundaries were not met for linifanib and the study failed to meet the primary end point. TTP and ORR favored linifanib; safety results favored sorafenib.

Structure, development, preclinical and clinical efficacy of tivozanib (KRN-951, AV-951).

Tivozanib hydrochloride monohydrate (tivozanib; formerly KRN-951, AV-951) is a potent pan-VEGF receptor tyrosine kinase inhibitor. The biological activity of tivozanib seems to outstand that of other VEGF tyrosine kinase inhibitors. In Phase I studies, observed side effects are generally mild, with hypertension being the most common adverse event. In single-agent Phase II and III studies in patients with advanced or metastatic renal cell carcinoma, tivozanib has demonstrated convincing clinical activity. Further clinical trials of tivozanib combined with various cytotoxic drug regimens as well as other classes of target-specific anticancer agents (e.g., mTOR inhibitors) for other indications are underway. Tivozanib has not yet been approved for regular use.

Sorafenib induced thyroiditis in two patients with hepatocellular carcinoma.

BACKGROUND: Sorafenib is a multi-targeted tyrosine kinase inhibitor licensed for the treatment of hepatocellular carcinoma and renal cell carcinoma. Thyroid function test abnormalities have been reported for different tyrosine kinase inhibitors, but only limited data on thyroid function test abnormalities related to sorafenib are available, demonstrating the occurrence of hypothyroidism in patients treated with sorafenib. SUMMARY: We describe two patients who developed temporary hyperthyroidism during the course of sorafenib treatment, which was followed by overt and subclinical hypothyroidism, respectively. Thyroid ultrasonography showed an atrophic thyroid gland in patient 1 , and signs of thyroiditis in patient 2 . Detailed reassessment of thyroid volumes on routinely performed computerized tomography scans showed a gradual decrease in thyroid volume during sorafenib treatment in one patient, suggesting progressive thyroid destruction. CONCLUSION: This case report describes in detail and for the first time two cases of sorafenib-induced thyroiditis. We assume that this sorafenib-induced destructive thyroiditis is an important cause of sorafenib-induced hypothyroidism.