Confirmation of combination hormone blocking therapy approach for recurrent prostate cancer

Image credit – University of California San Francisco

CANCER DIGEST – Jan. 28, 2024 – A new multi-center study, led by Rahul Aggarwall, MD, a professor at UCSF School of Medicine, has shown that combining two hormone blockade therapies further slows progression of recurrent prostate cancer. The study results appear in the Jan. 23, 2024 Journal of Clinical Oncology.

“New cancer therapies must clear a high bar to make their way to patients,” Aggarwal said in a press release. “With the evidence in this study and others, combination hormone therapy should be considered a standard of care in prostate cancer patients with high-risk relapse after prior treatment.”

The PRESTO Phase 3 clinical trial randomly assigned 503 prostate cancer patients at dozens of cancer centers across the country whose PSA levels doubled in less than nine months after having their prostates removed. Each was assigned to one of three hormone blockade therapies.

One third received testosterone lowering drugs such as Eligard® or Lupin®, commonly called androgen deprivation therapy or ADT, one third received ADT plus apalutamide (Erleada®), which blocks cells from taking up hormones, and one-third received ADT plus apalutamide plus abiraterone acetate (Zytiga®), which decreases the production of certain hormones in the body.

Patients stayed on the assigned drug combination for a year while their PSA (prostate specific antigen) levels were monitored. All combinations drastically lowered testosterone levels, which slowed the progression of their cancers, however, the single therapy group had their cancers progress, while those on the combination therapies remained cancer free.

Patients in all three regimens also experienced fatigue, hot flashes, lowered desire for sex and other side effects. Once the therapies were stopped the testosterone levels recovered at about the same rate.

The study results were consistent with other similar clinical trials using combinations of hormone blockade, including a study in the Oct. 19, 2023 New England Journal of Medicine show.