There were no differences in individual toxicities between the treatment arms, but cumulative toxicities were higher in the combination arm, according to the researchers.
The incidence of treatment-related adverse events (AEs) was 88% in the ipi + nivo arm and 90% in the nivo arm. The incidence of grade 3-5 treatment-related AEs was 39% and 31%, respectively.
The incidence of immune-mediated AEs was 65% in the ipi + nivo arm and 57% in the nivo arm. The incidence of immune-mediated grade 3-5 AEs was 20% and 11%, respectively.
There were six AEs leading to death in the ipi + nivo arm – two due to dyspnea, one due to colitis, and one due to respiratory failure. The attribution of one death is under review. For the remaining death, the exact cause is unknown.
There were two AEs leading to death in the nivo arm, both due to pneumonitis.
This study was supported by grants from the National Institutes of Health and by AbbVie, Amgen, AstraZeneca, Bristol-Myers Squibb, Genentech, and Pfizer through the Foundation for the National Institutes of Health in partnership with Friends of Cancer Research.
Dr. Bazhenova reported relationships with Epic Sciences, AbbVie, AstraZeneca, Boston Biomedical, Genentech/Roche, Lilly, Loxo, Pfizer, Takeda, and BeyondSpring Pharmaceuticals. Her colleagues reported relationships with these and other companies. Dr. Arbour reported a relationship with AstraZeneca.
SOURCE: Bazhenova L et al. ASCO 2019,