A recent phase 2 trial published in Journal for Immunotherapy of Cancer looked at the feasibility of taking intermittent nivolumab for the treatment of metastatic renal cell carcinoma (RCC) in patients who have already been treated with an anti-angiogenic therapy, such as sunitinib or pazopanib. Nivolumab is available for the second-line treatment of metastatic RCC in the UK, but the duration of treatment needed for sustained clinical benefit is unknown.
Fourteen patients were treated with nivolumab. After 12 weeks, if they had more than a 10% reduction in tumour burden, they were taken off nivolumab treatment and entered a treatment-free observation period with imaging every 12 weeks. If the tumour burden increased more than 10%, nivolumab was restarted. Five patients (36%) were taken off nivolumab (median decrease in tumour burden 46%) and all agreed to intermittent therapy. With a median follow-up of 48 weeks, only one patient restarted treatment with nivolumab. The four remaining patients have a sustained response for a median of 34 weeks (range, 16-53) off therapy.
The researchers suggest that further investigation of intermittent dosing with immunotherapy in metastatic RCC is warranted by these results.