Docetaxel Plus Hormone Therapy Improved QoL, Cost Effectiveness in Prostate Cancer

The addition of docetaxel to first-line long-term hormone therapy in patients with prostate cancer is associated with improved quality of life (QoL) benefits and cost effectiveness, according to study results.

During a session at the 2018 Genitourinary Cancers Symposium, Nicholas James, MBBS, PhD, Queen Elizabeth Hospital, presented results from the STAMPEDE trial, which looked at patients with M0 and M1 disease. The primary outcome of the trial was overall survival, and secondary endpoints included failure-free survival (FFS), progression-free survival, metastatic progression-free survival, skeletal-related events (SRE), toxicity, cost effectiveness, and QoL.

“Docetaxel produced a very consistent improvement in FFS across the whole trial,” said James. “The other thing that was very consistent across the whole trial was a 40% reduction in symptomatic skeletal events.”

The researchers used a standard model-based approach, explained James. All patients start hormone sensitive and they can progress to M0 castrate-resistant prostate cancer (CRPC) or M1 lymph node disease, CRPC bone, CRPC bone with a SRE, or CRPC visceral. The STAMPEDE trial data were used to determine how much each patient spent time in each category and what the QoL implications were. Additionally, the researchers also assessed cost effectiveness.

Because M0 patients have a 40% delay in the time to relapse, the patients getting docetaxel upfront spend more time hormone sensitive than patients in the control arm, said James. They subsequently spend less time with CRPC M0 or M1 lymph node only, and also less time with bone metastases, with or without an SRE. This correlates to more time with relatively good QoL, and less time with relatively poor QoL. For the metastatic setting, the same effects were observed. Patients spend more time in the hormone-sensitive state. This means less time with the factors that harm your QoL and increase your costs, said James.

“For metastatic patients where there’s a survival advantage, not surprisingly, you see a quality-adjusted life years (QALY) gain as well,” said James. “In other words, the benefits of not relapsing, not having SREs, wipes out the quality of life penalty that you incur from your upfront chemotherapy.”

The same effect was seen in M0 patients. Although there wasn’t a robust survival advantage in this setting, there is still a QALY gain.

For treatment with docetaxel, end-of-life costs didn’t change substantially, docetaxel costs increased, management costs in general went up, and over the course of the trial, the costs of other life prolonging therapies went up. However, there’s been big changes over the duration of the trial with the emergence of androgen receptor targeted therapies, said James.

The researchers remodeled the data using patients who had enrolled later in the trial and who were getting abiraterone/enzalutamide for M1 CRPC. When they did that, there were still increases in docetaxel costs, management costs, and there was little effect on end-of-life care. However, there was a significant reduction in the use of other life prolonging therapies compared to the control arm. When looking at net total cost, there was a reduction in overall lifetime care costs in M0 disease from the upfront addition of docetaxel. While there was a net increase for the metastatic setting, the total cost was approximately £3000 over the lifetime of the patient.

“Upfront docetaxel results in robust gain in quality adjusted life years in all subgroups,” concluded James. “It supports existing healthcare policy in metastatic patients, but it also supports the use of docetaxel in high-risk non-metastatic patients.”