mTOR Inhibitors for Cancer May Protect Fertility in Younger Female Patients

A class of targeted drugs used to treat cancer may also preserve fertility in some younger women being treated for the disease.

A study in mice suggests that mTOR inhibitors protect the ovaries from chemotherapy- induced damage and infertility, announced Cancer Currents, a news blog published by the National Cancer Institute. Mice treated with both mTOR inhibitors and chemotherapy had more babies than those that received only chemotherapy. mTOR inhibitors work by targeting a protein that contributes to cancers and by slowing the growth of blood vessels that feed tumors. mTOR inhibitors approved by the Food and Drug Administration to treat a range of cancers include Afinitor (everolimus) and Torisel (temsirolimus).

Currently, younger women undergoing chemotherapy may take Zoladex (goserelin) or Lupron (leuprolide), which protect the ovaries by shutting them down during treatment, or may cryopreserve their eggs or fertilized embryos. But these options are not appropriate for everyone. In the study, a team from NYU Langone’s Perlmutter Cancer Center tested Afinitor and the experimental mTOR inhibitor sapanisertib (also known as INK128), Cancer Currents explained. They discovered that mice treated with chemotherapy alone ended up infertile, while mice that received both drugs became pregnant at normal rates. Mice taking chemotherapy alone gave birth to less than half as many pups as mice that received both drugs.

The mice taking both drugs did not experience side effects.

Next steps will involve trying lower doses in animals and designing trials to test the strategy in women.