Patients on targeted therapy were more likely to develop conditions such as heart attacks and stroke than were those who took cytokine therapy (adjusted hazard ratio, 1.80; 95% confidence interval [CI] 1.19-2.74), according to a retrospective Taiwanese study reports.
“These findings may inform the evaluation of cardiovascular risk when considering targeted cancer therapies for patients with advanced renal cell carcinoma in real-world clinical practice,” wrote the authors of the report, which appeared in JACC: CardioOncology.
The study notes that one kind of targeted therapy – tyrosine kinase inhibitors with anti–vascular endothelial growth factor (VEGFR-TKI) have been linked to higher rates of major adverse cardiovascular events (1.38-22.7). There have also been reports linking another kind of targeted therapy, mechanistic target of rapamycin inhibitors (mTOR), to major adverse cardiovascular events.
In the new study, Dong-Yi Chen, MD, of Chang Gung University, Taiwan, and colleagues, tracked patients with renal cell carcinoma who underwent treatment with targeted therapy (sunitinib, sorafenib, pazopanib, everolimus, or temsirolimus, (n = 2,257, 81%) or cytokine therapy (interleukin-2 or interferon gamma, n = 528, 19%) from 2007 to 2018.
The two groups had similar gender, age and socioeconomic levels. Combined, the groups were 74% male, the median age was 63, and 68% had hypertension.
After stabilized inverse probability of treatment weighting, the adjusted incidence rates of major cardiovascular events were 6.65 and 3.36 per 100 person-years in the targeted and cytokine therapy groups, respectively. “The higher cardiovascular risk of the targeted group was driven primarily by the VEGFR TKI–treated patients,” the authors wrote.
Two drugs were linked to statistically significant higher rates of major cardiovascular adverse events compared with the reference drug sunitinib: the VEGFR TKI sorafenib (univariable HR, 1.94, 95% CI, 1.11-3.39), P = .021) and the mTOR temsirolimus (univariable HR, 2.11, 95% CI, 1.24-3.59, P = .006). Sunitinib was by far the most commonly used targeted therapy drug.
Among patients on targeted therapy, several factors were linked to higher rates of major cardiovascular events, such as baseline history of heart failure (HR, 3.88, 95% CI, 2.25-6.71), atrial fibrillation (HR, 3.60, 95% CI, 2.16-5.99), venous thromboembolism (HR, 2.50, 95% CI, 1.27-4.92), ischemic stroke (HR, 1.88, 95% CI, 1.14-3.11), and age at least 65 years (HR, 1.81, 95% CI, 1.27-2.58).
According to the authors, there are several theories about why targeted therapy may boost the risk of major adverse cardiovascular risk. “VEGF signaling inhibitors have been associated with hypertension,” which is a risk factor for cardiac death, they noted. Also, “multi-receptor TKIs, including VEGFR and platelet-derived growth factor receptor inhibitors, could destabilize the coronary microvascular endothelial network and reduce coronary flow reserve, leading to an increased risk for thrombosis and arterial ischemic events, including myocardial infarction and ischemic stroke.”
The study was funded by Chang Gung Memorial Hospital.