BACKGROUND: We previously reported preliminary results of our phase I study of continuous daily sorafenib with bevacizumab every other week for solid tumours. Toxicity was moderate, leading to additional dose levels (DL) testing intermittent sorafenib dosing. . Outcome and toxicity data from 19 epithelial ovarian cancer (EOC) patients from DL 1 -5 were analysed. RESULTS: Fewer patients required sorafenib dose reduction with the intermittent schedule (41 vs 74% daily, P ¼ 0.01). Hand -foot skin reaction (HFSR) remained the primary cause of dose reduction (n ¼ 5). Partial responses (12%) or disease stabilisation X4 months (53%; median 6 (4 -26)) occurred in most patients on the intermittent schedule. Partial response occurred in 47% EOC patients treated in pooled analysis of duration 4 -37 months. CONCLUSION: Intermittent sorafenib dosing with bevacizumab has promising clinical activity and less sorafenib dose reduction and side effects, but does not ameliorate HFSR. We are conducting a phase II clinical trial with intermittent sorafenib and bevacizumab in patients with EOC.

As has been reported with other chemotherapeutic agents, evidence is emerging to suggest that increased taxol dose intensity is associated with improved therapeutic efficacy. Granulocyte colony-stimulating factor (G-CSF) effectively protects the bone marrow from taxol-induced neutropenia and allows for higher taxol dose administration. This report addresses the optimal use of G-CSF as a supportive agent for dose-intense taxol therapy. Forty-seven patients were evaluated. Each ovarian cancer patient received taxol with G-CSF support, with starting doses of 250 mg/m2 per 21 days and 10 micrograms/kg/d, respectively. Five patients were treated with the same dose of G-CSF for multiple cycles. Forty-two patients were given “flexibleflexible” G-CSF dosing. Instead of reducing taxol dose after a cycle of therapy complicated by febrile neutropenia (F+N+), the G-CSF dose was increased. Only after a second episode of F+N+ was the taxol dose reduced. The initial 5 patients who developed F+N+ after taxol (250 mg/m2) and G-CSF (10 micrograms/kg/d) were retreated at the same doses of both drugs; subsequently, 4 of 5 patients had another episode of F+N+. With flexible G-CSF dosing, taxol dose intensity could be maintained at the target level in 34 of 42 patients (81% of the cohort). Sixteen of these patients (38% of the cohort) would have required taxol dose reductions for F+N+ if flexible G-CSF dosing had not been used. By increasing the G-CSF dose when indicated, patients at high risk for recurrence of F+N+, because they had already experienced one episode, appeared to have a lower risk of developing a recurrent episode. These data suggest that flexible G-CSF dosing may have merit and may allow the administration of more dose- intense taxol. A prospective, randomized, controlled clinical trial of flexible G-CSF dosing versus fixed-dose G-CSF appears warranted.