Enobosarm and Breast Cancer

We use affiliate links. If you purchase something using one of these links, we may receive compensation or commission.

Ostarine Enobosarm breast cancerAre you wondering if Enobosarm (also known as Ostarine or MK-2866) can be used to treat breast cancer? We’ll take a look at this drug and see if there is any promise for treatment in breast cancer.

What is Enobosarm?

Ostarine is sometimes referred to as Enobosarm or MK-2866. It’s a SARM or selective androgen receptor modulator. They are designed to specifically target certain types of androgen receptors while ignoring others. This drug was originally developed to treat conditions like muscle wasting and osteoporosis.

SARMs target androgen receptors in a way that is similar to anabolic steroids. However, steroids target all androgen receptors where SARMs can target specific receptors such as skeletal tissue. Because of this SARMs have fewer side effects and do not seem to cause any masculine features in females.

Can Enobosarm Breast Cancer?

Some researchers have hope that SARMs like Enobosarm may have the potential to treat breast cancer. According to the National Breast Cancer Foundation, there were Phase II trials of Enobosarm that showed it was effective in treating metastatic ER+  and AR+ breast cancer. Patients were said to reach stable disease. This is exceptional because Enobosarm is the only new generation Androgen Receptor (AR) drug to achieve this outcome. The safety and dosages were considered in the study and Enobosarm was the only AR target therapy trial where the end goal was achieved.

There is another study in the UK that is examining if Enobosarm could be a benefit to patients, specifically women, with newly diagnosed ER+ breast cancer. If it turns out that Enobosarm is effective, it could be a potential treatment for the late stages and early stages of the disease. This will provide patients and doctors with more alternatives when deciding the proper course of treatment.

Another pilot study is being funded by the NBCF in Australia run by Professor Wayne Tilley of the University of Adelaide. The professors say that he is excited about the potential of Enobosarm and other SARMs as treatment options for breast cancer.

“Our data show that activation of androgen receptors with Enobosarm (or a similar drug) can inhibit tumors that are endocrine-resistant,” he said. “This opens the door for a new treatment avenue that could significantly prolong life.”

One of the main concerns of Tilley is that of patient well being when undergoing breast cancer treatment. Many treatments can leave patients feeling miserable. SARMs may be different in this aspect.

“We have been advocates for SARMs because they not only have the potential to prolong life, but they have the potential to make patients feel better while on therapy,” he explained. “This reduction in negative side effects is because the drugs promote bone, muscle, and brain health.”


There have been successful studies on the effects of Enobosarm and other SARM drugs in the treatment of breast cancer. One trial has shown that Enobosarm is effective in treating ER+ and AR+ metastatic breast cancer. A new trial is underway in the UK that we’re hopeful will find the same results. Doctors around the world are excited by these findings. However, more research is needed to determine if Enobosarm is an effective treatment for breast cancer.