Enzalutamide Induces Added Benefit for Patients with Castration-Resistant Prostate Cancer

Researchers found a hint of added benefit in terms of mortality due to the longer overall survival with the drug enzalutamide (Xtandi) to treat adult patients with high-risk non-metastatic castration-resistant prostate cancer, according to a reassessment by the German Institute for Quality and Efficiency in Health Care (IQWiG).

The drug had previously been examined twice before in 2018 and 2019 to see if there was an advantage in comparison with the appropriate comparator therapy. Both the first and second data cut-offs for the PROSPER study found no added benefit for the drug to treat high-risk non-metastatic castration-resistant prostate cancer.

“Since the study was not yet completed, the Federal Joint Committee (G-BA) limited its corresponding decision,” the press release stated. “After expiry of the decision, IQWiG reassessed the drug on the basis of the third data cut-off of the study, which had been completed in the meantime.”

In regard to morbidity and health-related-quality, no new findings existed when compared to the first assessment of the drug. As a result, no added benefit was determined for these outcome categories.

Where that differed was in terms of mortality for the third data cut-off when compared to the first assessment. The data found that patients in the enzalutamide arm survived considerably longer than patients in the comparator arm.

For drug side effects, the researchers explained that the results are mixed. For renal and urinary disorders, there were signs of a major advantage for patients although its unclear whether these are a result of treatment or symptoms of the disease. More, signs of disadvantages were found for enzalutamide when compared to watchful waiting while maintaining ongoing conventional androgen deprivation therapy.

Regardless, the disadvantages did not raise doubt about the advantages, resulting in the overall assessment finding an added benefit of enzalutamide compared to the appropriate comparator therapy.

Prostate cancer is the most common form of cancer for men in the United States. More, the American Cancer Society estimates that about 190,000 men will be diagnosed with prostate cancer and over 33,000 men in the United States will die from the cancer in the 2020.

Reference:

Castration-resistant prostate cancer at high risk of metastasis: enzalutamide has added benefit [news release]. Published August 19, 2020. https://www.eurekalert.org/pub_releases/2020-08/ifqa-cpc081920.php. Accessed October 7, 2020/