Conclusions
The recommended phase 2 doses and schedules for this combination are topotecan 0.75mg/m2 IV days 1-5, cyclophosphamide 250mg/m2 IV days 1-5, and cabozantinib 25mg/m2 days 8-21. Non-concomitant administration of cabozantinib with cytotoxic therapy in this population has acceptable toxicity while allowing for potential disease control.