Correlation Between Sorafenib Plasma Concentrations, Toxicity and Disease Control Rate in Patients Treated by Sorafenib for Hepatocellular Carcinoma

Sorafenib is the standard of care for the palliative treatment of HCC. The recommended dose of sorafenib in patients with HCC is 400 mg twice daily. Sorafenib dose-limiting toxicities include diarrhea, arterial hypertension and hand-foot syndrome. Owing a large inter-patient variability (near 50%) of sorafenib Area Under the Curve (AUC) over 12h, an over-exposure to sorafenib could explain acute toxicity. On the other hand, a suboptimal exposure could result in an insufficient anti-tumor activity as suggested by a recent study. This inter-patient variability of sorafenib pharmacokinetic is especially relevant in HCC. Indeed, most of HCC are developed on cirrhotic liver with often an impaired liver function, a decrease of albuminemia and sometimes ascitis. All these parameters are likely to impact the sorafenib pharmacokinetic. The aim of this pilot study is to correlate the sorafenib plasma concentration to observed toxicity and to the disease control rate in 100 patients.

The dose of sorafenib will be the recommended dose: 400 mg twice daily. Sorafenib daily doses will be only adjusted by the clinician on adverse event. Values of sorafenib AUC will not be transmitted to clinician.

Patients will be followed during 12 months with 5 visits: Week 4, Week 8, Week 16, Month 6 and Month 12. Adverse event related to sorafenib will be recorded and graded according to the NCI-CTC for Adverse Event during all the study period. Sorafenib plasma concentrations will be assessed at 4, 8 and 16 weeks. An additional dosage could be performed between W1 and W4, before dose modification, if a dose modification is necessary due to adverse events before W4.