Enzalutamide for the treatment of metastatic prostate cancer during or after chemotherapy

Men whose metastatic prostate cancer progresses despite using conventional hormone blockers, and who have worsening symptoms like pain, are typically offered chemotherapy with the drug docetaxel. If the cancer progresses during or after this treatment, supportive care is an option. It is adjusted based on the patient's individual needs and symptoms. Supportive care aims to relieve the symptoms as much as possible and improve quality of life. It includes things like pain management therapy, sometimes with very strong painkillers.

What was enzalutamide compared with?

In late 2013 and early 2014, the Institute for Quality and Efficiency in Health Care (IQWiG, Germany) looked into the possible advantages and disadvantages of enzalutamide when used in addition to supportive care.

One relevant study was made available to IQWiG. All of the study participants received supportive care, and two thirds also took enzalutamide.

What advantages does enzalutamide have?

  • Life expectancy: There was weak evidence that enzalutamide can increase life expectancy: Half of the men had passed away within about 14 months in the supportive care group, and within about 18 months in the group that received both supportive care and enzalutamide. The data wasn’t as conclusive for men with metastatic tumors in their internal organs.
  • Bone damage: Research has suggested that enzalutamide can delay the onset of complications affecting the bones, such as fractures or surgery: Half of the men had developed such complications after about 13 months in the supportive care group, and after about 17 months in the group that received both supportive care and enzalutamide. This advantage is larger for men under the age of 65 than for older men.
  • Pain: The study results suggest that enzalutamide can relieve pain and delay the point at which the pain becomes more severe.
  • Severe side effects: There is some weak evidence that enzalutamide can delay the need for other treatments. For instance, there is less need for strong painkillers that can cause side effects like vomiting and problems affecting urination. Half of the men had developed these kinds of side effects after about 4 months in the supportive care group, and after about 13 months in the group that received both supportive care and enzalutamide.

What are the disadvantages of enzalutamide?

There is no data suggesting that enzalutamide has any disadvantages compared with supportive care.

What remains unanswered?

  • Quality of life: The study didn’t include any suitable data about the influence of enzalutamide on quality of life.
  • Seizures: Based on the available data, it’s not possible to say whether seizures are more or less common in people who take enzalutamide in addition to having supportive care.
Labels: C61, Enzalutamide, Xtandi