Selected adverse events in cancer patients treated with vascular endothelial growth factor inhibitors

To evaluate the safety profile of new drugs, it is important to quantify the rates of adverse events (AE). There has been little to no research on the safety of vascular endothelial growth factor (VEGF) inhibitors in population-based settings. The purpose of this study was to further the understanding of the incidence of AEs in a population-based representative cancer population receiving VEGF inhibitors where there currently is a deep lack of knowledge.

We conducted a retrospective cohort study using data from an administrative claims database between January 1, 2004 and December 31, 2010. Patients were included into the study if they had at least two malignant primary cancer diagnoses codes (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM]: 140-209 [not including 196-199.0]) from the same cancer site and a prescription for a VEGF inhibitor. We estimated the incidence rate (IR) and 95% confidence interval (CI) for each adverse event under study.

2326 patients met the inclusion and exclusion criteria. The mean age for the cohort was 57.3 where 79% of the patients were 50 years of age or older. The most common adverse event was nausea and vomiting (IR = 651.7/1000 person-years; 95% CI = 589.7-718.4). Other common adverse events were hypertension (IR = 452.9/1000 person-years; 95% CI = 394.9-517.1) and hemorrhage (IR = 375.2/1000 person-years; 95% CI = 332.2-422.3). The least common adverse events were rare dermatologic diseases such as Stevens-Johnson syndrome and toxic epidermal necrolysis where no cases were observed.

The rates detailed in this analysis are helpful in understanding the benefit risk of VEGF inhibitors as they are prescribed in the real world. Although no formal comparisons were conducted, the VEGF inhibitors evaluated in this study appeared to have overlapping toxicity profiles; however, the manner in which these AEs are listed in the prescribing information was not always consistent.