Not yet recruitingPHASE2INTERVENTIONAL

Clinical Trial to Observe the Effects of Tamoxifen on Testosterone Recovery in Medically Castrated Prostate Cancer Patients

This study is investigating if an existing medicine called Tamoxifen can help men with prostate cancer recover their normal testosterone levels more quickly. Many men whose prostate cancer treatment includes hormone-lowering therapy, known as ADT, find that their testosterone takes a long time to return to normal, or sometimes doesn't fully recover. Low testosterone can cause various physical and emotional side effects. Tamoxifen is a well-known drug that has been used for other conditions. Researchers believe it might offer a simple and affordable way to speed up this testosterone recovery. The study hopes to find a solution that helps men feel better after their prostate cancer treatment, especially in places where resources might be limited.

At a glance

Status

Not yet recruiting

Phase

PHASE2

Sponsor

University Health Network, Toronto

Enrolment target

Start

01 Jul 2026

Estimated completion

01 Oct 2030

Hypogonadism Prostate Cancer

What is this study about?

This study is about helping men who have had a type of prostate cancer treatment called androgen deprivation therapy, or ADT. This treatment works by lowering the amount of testosterone in the body, which helps to control the cancer. However, a common problem with ADT is that it can take a long time for a man's testosterone levels to return to normal after the treatment stops. For some men, their testosterone might not even fully recover, which can lead to uncomfortable side effects like feeling tired, changes in mood, and other physical issues.

The researchers are looking at a medicine called Tamoxifen. You might have heard of it because it's used for other conditions, especially in breast cancer. Tamoxifen works by affecting how certain hormones, like oestrogen, act in the body. Scientists think it might be able to encourage the body to start making testosterone again more quickly after ADT. The aim is to reduce the time men spend with low testosterone levels, helping them to feel more like themselves sooner.

This is important because improving testosterone recovery could significantly improve the quality of life for many men after prostate cancer treatment. If Tamoxifen proves effective, it could offer a simple, cost-effective, and widely available option to help manage a common side effect of life-saving cancer treatment, benefitting patients and healthcare systems, particularly in areas with fewer medical resources.

Key takeaways

This study investigates if Tamoxifen can speed up testosterone recovery in men after prostate cancer hormone treatment (ADT).
Many men experience slow or incomplete testosterone recovery after ADT, leading to side effects.
Tamoxifen is an existing medicine that might offer a simple and affordable solution.
The goal is to improve quality of life for men after prostate cancer treatment.
Participation involves taking Tamoxifen and having regular health check-ups and blood tests.

Who may be eligible?

To join this study, you need to be a man over 18 years old who has been diagnosed with prostate cancer. You must have received hormone-lowering treatment (ADT) for either 6 months or between 18 and 36 months as part of your prostate cancer treatment. Importantly, you should have finished your ADT treatment and have been off it for a period equal to how long your last ADT injection was meant to last (for example, if your last injection was for 3 months, you must have been off it for 3 months). Your testosterone levels should still be low (effectively castrated) within six weeks of thinking about joining the study, and you need to be generally well enough to take part.

There are also some reasons why you might not be able to join. For example, if you have certain genetic variations, a history of blood clots, a stroke, or specific liver problems, the study would not be suitable for you. You also couldn't join if you take certain medicines like some antidepressants (SSRI’s), certain blood thinners, chemotherapy drugs, or aromatase inhibitors. If you have had other types of cancer in the last five years (excluding some skin cancers), or if you're already taking experimental drugs, you wouldn't be eligible. The team will carefully check all these details with you.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you a man at least 18 years old with prostate cancer?
Have you had hormone-lowering treatment (ADT) for prostate cancer?
Have you finished your ADT treatment and been off it for the required period?
Are your testosterone levels still low (effectively castrated)?
Do you have a history of blood clots or stroke?
Are you currently taking certain medications like specific antidepressants, strong blood thinners, or chemotherapy?

Answer every question to see your result.

What does participation involve?

If you decide to take part in this study, you will be given Tamoxifen, and the team will closely monitor its effects. This will involve regular visits to the clinic for check-ups, blood tests to measure your hormone levels, and assessments of your general health and how you are feeling. The study will look at how quickly your testosterone levels recover while you are taking the medication. The total duration of your involvement will depend on your individual response and the study's monitoring schedule, but detailed information will be provided before you agree to take part. All details about your specific schedule, including the number of visits and tests, will be fully explained to you.

Potential risks and benefits

Participating in this study might offer a potential benefit of helping your testosterone levels recover faster after your prostate cancer treatment, which could improve your overall well-being and reduce uncomfortable symptoms. However, like all medications, Tamoxifen has potential side effects, and some may be serious, though these will be fully explained by the study team. They will carefully monitor you for any problems. You have the right to withdraw from the study at any time, for any reason, without affecting your regular medical care.

Locations (1)

University Health Network - Princess Margaret Cancer Center
Verified postcode
Toronto, Canada

Common questions

What is ADT?

ADT stands for Androgen Deprivation Therapy. It's a type of prostate cancer treatment that lowers the amount of testosterone in your body to help control the cancer.

What is Tamoxifen?

Tamoxifen is a well-known medicine commonly used to treat certain types of breast cancer. It works by affecting how hormones interact with your body.

Why is fast testosterone recovery important?

Recovering normal testosterone levels faster can help improve your energy, mood, and overall physical health, reversing many of the side effects of low testosterone from ADT.

Will I still get my usual prostate cancer care if I join?

Yes, absolutely. Joining this study will not affect the prostate cancer care you would normally receive from your doctors.

How long will I be in the study?

The exact duration will be explained to you by the study team, as it can vary, but generally involves regular check-ups and monitoring over a period of time after you’ve stopped ADT.

How to find out more

Alejandro Berlin, MD

alejandro.berlin@uhn.ca 416-946-4501 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.