Multicenter phase 2 trial of GX-188E DNA vaccine plus pembrolizumab in HPV16- and/or 18-positive recurrent or advanced cervical cancer

GX-188E is a DNA vaccine that encodes HPV16 and HPV18 E6 and E7 proteins. The phase 2 KEYNOTE-567 trial at nine centers in South Korea evaluated the combination of GX-188E DNA vaccine plus pembrolizumab in HPV16- and/or HPV18-positive recurrent or advanced cervical cancer. The combination resulted in objective response rate of 35.0% (95% CI 23.1-48.4) with complete response in 8.3% and a median duration of response 12.3 months. The median progression-free survival was 4.4 months (95% CI 2.1-8.3) and the median overall survival was 23.8 months (14.0-NR). Treatment-related adverse events were reported for 33.8%; grade 3 or 4 TRAEs for 6.2%; there was no grade 5 TRAE. The authors conclude that the combination of the vaccine with pembrolizumab was safe and had promising activity among patients with recurrent or advanced HPV-positive cervical cancer.