By Will Boggs MD
NEW YORK (Reuters Health) - 15/8/2019
Men with prostate cancer and pre-existing cardiovascular disease (CVD) have worse short-term mortality following treatment with oral androgen-signaling inhibitors than do similar men without CVD, according to a database study.
"Approved cancer therapies do not always meet the therapeutic expectations promised in clinical trials because trials usually exclude men with significant comorbidities or polypharmacy," said Dr. Grace Lu-Yao from Sidney Kimmel Medical College, in Philadelphia.
"Our study showed that two-thirds of the patients treated with abiraterone acetate (AA) or enzalutamide (ENZ) might not be eligible for the pivotal trial. The magnitude of benefit observed in the pivotal trial might not be generalized to these patients with high-risk CVD events," she told Reuters Health by email.
Dr. Lu-Yao and colleagues used Surveillance, Epidemiology, and End Results (SEER) and Medicare data to test their hypothesis that pre-existing CVD is associated with higher six-month mortality after AA or ENZ treatment.
Two-thirds of the 3,876 patients included in this study had one or more CVD conditions (acute myocardial infarction, atrial fibrillation, chronic heart failure, stroke, or ischemic heart disease) before receiving AA or ENZ.
Among men not treated with docetaxel-based chemotherapy, all-cause crude mortality at six months posttreatment was higher in those with any CVD condition than in those with no CVD, but only if they took AA.
In contrast, there were no differences in six-month mortality between the individual CVD groups and the no-CVD group among men who received chemotherapy, regardless of which oral androgen-signaling inhibitor they received, the researchers report in European Urology, online August 13. Overall, men with three or more CVD diagnoses had 43% (with AA) and 56% (with ENZ) higher six-month mortality risk compared with those without CVD, both significant results.
Hospitalization rates did not differ significantly among post-chemotherapy patients who took AA or ENZ, but men with one to two CVDs had a 43% higher hospitalization rate compared with their peers without CVD.
Among men not treated with chemotherapy who had three or more CVDs, those treated with ENZ had a 41% lower hospitalization rate than did those treated with AA.
"More research is needed to develop clinical algorithms for patient selection, monitoring, and treatment modifications to optimize the treatment outcomes of many patients with pre-existing cardiovascular conditions," Dr. Lu-Yao said. "A multispecialty-care-team approach with a cardiologist will likely provide the best care for patients with a high baseline risk of CVD events."
"Once a drug is approved based on the pivotal trial with relatively healthy patients, it is crucial to conduct studies in patients with various medical conditions or taking other co-medications to ensure the safety of the drugs in a broad population," she added.
Eur Urol 2019.
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