Safety and efficacy of PD-1 blockade-activated multiple antigen-specific cellular therapy alone or in combination with apatinib in patients with advanced solid tumors: a pooled analysis of two prospective trials.

BACKGROUND

The lethal effects of multiple antigen-specific cellular therapy (MASCT) may be enhanced by blocking PD-1 in vitro and vascular endothelial growth factor receptor 2 inhibitor (apatinib). We analyzed the pooled data from our phase I/II trials to determine the toxicity and efficacy of PD-1 blockade (SHR-1210)-activated MASCT (aMASCT) alone or in combination with apatinib in advanced solid tumors.

METHODS

Patients with advanced solid tumors received aMASCT alone (n = 32) or aMASCT plus apatinib (500 mg q.d., n = 38) after standard treatment. The safety profile was the primary end point. The secondary end points were antitumor response, progression-free survival (PFS), and overall survival (OS). The circulating T cells were quantified before and after aMASCT infusion.

RESULTS

Treatment-related adverse events (AEs) occurred in 18/32 (56.3%) and 25/38 (65.8%) patients in the aMASCT and aMASCT plus apatinib groups, respectively. No serious AEs were reported, and apatinib did not increase immunotherapy-related toxicity. The objective response rate (34.2% and 18.8%) and PFS (median 6.0 and 4.5 months, P = 0.002) were improved in the aMASCT plus apatinib group compared with the aMASCT group; however, the OS was not improved (median 10.0 and 8.2 months, P = 0.098). Multivariate analyses indicated that two or more cycles of aMASCT treatment was an independent and favorable prognostic factor of PFS and OS. The circulating T cells increased and Tregs decreased in both groups after one cycle of aMASCT treatment.

CONCLUSIONS

Treatment with aMASCT plus apatinib was safe and effective for the management of advanced solid tumors.