Sorafenib rechallenge in patients with metastatic renal cell carcinoma

What's known on the subject? and What does the study add? Targeted agents with a similar or different target molecule are often used sequentially in the treatment of metastatic RCC. Two tyrosine kinase inhibitors, sorafenib and sunitinib, have been reported to show little cross-resistance, when used sequentially. In addition, a recent report showed that sunitinib rechallenge could potentially benefit selected patients. This case series shows that patients once refractory to sorafenib could regain disease control on rechallenge with sorafenib during sequential treatment. Outcomes of the sorafenib rechallenge were not significantly affected by the response to the initial sorafenib treatment or by the duration of intervening treatments between first sorafenib and rechallenge.

To investigate clinical outcomes of sorafenib rechallenge during sequential therapy for patients with metastatic renal cell carcinoma (RCC).

Patients with metastatic RCC who received sorafenib rechallenge after failed treatment first with sorafenib and subsequently with other agents, were retrospectively reviewed for patient characteristics, best response, progression-free survival (PFS), and adverse events (AEs).

Of the 14 patients who received sorafenib rechallenge, 12 were evaluable for response. Eleven patients had previously undergone nephrectomy, and 10 had previously received systemic therapy, mostly interferon-α (nine patients) and interleukin-2 (six patients), with a median duration of 9 months. The best responses after the first sorafenib therapy were partial response (PR) in two patients, stable disease (SD) in seven, and progressive disease (PD) in two. The median PFS was 5.7 months. Initial sorafenib therapy was discontinued because of PD in eight patients and AEs in four patients. Rechallenge with sorafenib was undertaken after a 7.6 month median interval from the initial sorafenib challenge. Eight patients achieved SD on sorafenib rechallenge and median PFS was 5.4 (95% confidence interval, 3.8-7.0) months. The outcome of the sorafenib rechallenge was not significantly affected by the response to the initial sorafenib treatment or by the duration of treatments received between first sorafenib and rechallenge. No severe AE was newly observed on the rechallenge.

In the systemic treatment of advanced RCC, it was suggested that patients once refractory to sorafenib could regain disease control on rechallenge with sorafenib during sequential treatment.