Efficacy of an ultra-low dose of immunotherapy in relapsed refrfactory solid tumors

Data from the the DELII phase III superiority trial, recently published on the Journal of Clinical Oncology, shows that an ultra-low dose of the immune checkpoint inhibitor nivolumab retains clinical efficacy in patients with relapsed refractory solid tumors, with fewer toxicity and better quality of life, thus potentially improving affordability of immunotherapy.

The study is an open-label phase III superiority trial where 500 patients with advanced, heavily pretreated solid tumors (of which 52% head and neck cancers, 36% lung cancers) were randomized to receive an ultra-low dose of nivolumab (20 mg every 2 weeks, i.e. 8% of the conventional dose) or chemotherapy. Results showed that median overall survival was 5.88 months with ultra-low dose nivolumab versus 4.7 months with chemotherapy; one year overall survival were 27.3% and 16.9% respectively. Median progression-free survival and objective response rates did not significantly differ between the two treatment groups, but duration of response reached 8.28 months with ultra-low dose nivolumab versus 4.93 months with chemotherapy. Safety with ultra-low dose nivolumab was substantially improved and quality of life was significantly better compared with chemotherapy. As authors point out, «only a very small proportion of eligible patients in many low- and middle-income countries are currently able to receive checkpoint inhibitors because of cost limitations. These findings support re-evaluation of immune checkpoint inhibitor dosing strategies and may enhance global access», they conclude.