Immunotherapy link to fertility problems

Egg freezing may be needed for cancer patients receiving immunotherapy, Australian scientists have discovered. This is what we know so far.

Immunotherapy which has been considered less damaging to the body than chemotherapy could cause fertility problems, Australian researchers have found.

While cancer patients facing chemotherapy have been encouraged to freeze their eggs to ensure having a baby, scientists at Monash University have found that fertility preservation may also be needed for those receiving certain immunotherapies.

A preclinical trial led by the Biomedicine Discovery Institute at Monash University and the Peter MacCallum Cancer Centre, showed that immune checkpoint inhibitors, a common type of immunotherapy drug, resulted in permanent damage to mouse ovaries and the eggs stored inside.

Traditional cancer therapies, such as chemotherapy and radiotherapy, are already linked to permanent, negative side effects on the ovaries. This can lead to infertility and premature menopause in young girls and women.

Published in Nature Cancer, researchers found that checkpoint inhibitor immunotherapy reduced the number and quality of their eggs, interfered with ovulation, and disrupted the fertility cycle.

Until now the potential fertility side effects of immunotherapy, an emerging and increasingly common cancer treatment that stimulates the immune system, have been unknown.

The study found that a type of immunotherapy called immune checkpoint inhibitors, which ‘release the brakes’ on the immune system to enhance a patient’s ability to fight cancer, could impair immediate and future fertility.

Its authors said studies in female patients were now needed to investigate the findings. In the meantime, fertility preservation through egg or embryo freezing should be considered for women using these immunotherapies.

Co-lead author Lauren Alesi, a PhD candidate in the Monash Biomedicine Discovery Institute Ovarian Biology Laboratory, said human studies must now be prioritised.

“Initially these treatments were thought to be less damaging (than chemo and radiotherapy) in the context of off-target effects to the body in general. However, it is now clear that inflammatory side effects in other organ systems are quite common with these drugs.

“Our study highlights that caution should be exercised by clinicians and their patients, for whom fertility may be a concern. Studies in women receiving these drugs must now be prioritised.”

Peter MacCallum Cancer Centre Specialist Medical Oncologist Professor in breast cancer and a senior author on the study Sherene Loi said further research into how these drugs impact the ovarian function and fertility of women receiving these drugs must be prioritised and should be included in future clinical trials involving women of reproductive age.