Case Study Links Keytruda to Severe Immune-Related Enteritis After Pregnancy Exposure

Exposure to a common cancer drug during pregnancy may put infants at risk of developing immune-related inflammatory conditions, according to a recent case study.

Keytruda (pembrolizumab) is an immunotherapy drug often used alongside other cancer drugs to treat late-stage and reoccurring cancers of the skin, lungs, head, neck, lymph nodes and bladder, among others. It works by boosting the immune system to help the body identify and destroy difficult-to-treat cancer cells.

In a report published this month in the New England Journal of Medicine, Dutch researchers indicate that a newborn baby exposed to Keytruda before birth suffered severe immune-related enteritis.

As a result, doctors indicate prenatal Keytruda exposure, especially during the second or third pregnancy trimester, may be associated with an increased risk of adverse immune-related health events in newly born infants, including gastroenteritis and gastroenterocolitis.

Keytruda Linked to Infant Gastroenteritis

The case study describes complications experienced by a 4-month-old infant, who developed severe immune-related gastroenterocolitis after his mother received Keytruda injections for melanoma treatment. She received the injections every six weeks for a period of four months, starting from the 16^th week of pregnancy.

The chronic inflammation resembled reported cases of immune-related gastrointestinal toxicity and colitis in adult cancer patients who received the drug. The infant reportedly suffered from severe diarrhea and failure to thrive.

After ruling out other potential illnesses and causes, doctors determined the condition was induced by Keytruda side effects. The infant successfully recovered after 10 weeks of extensive treatment.

Researchers indicate that at least 14 similar cases of fetal drug exposure have been reported to date. The majority of those involved exposure during the second or third trimester, which resulted in pregnancy termination or preterm delivery.

As a result of the potential risks, doctors called for further investigations into the safety of Keytruda in treating cancer during pregnancy, to better understand the impact it has on babies before and after birth.

Keytruda Risks

The U.S. Food and Drug Administration (FDA) issued drug safety guidance to health care professionals in May 2018, indicating cancer patients who used Keytruda had lower survival rates when the drug was used as a single therapy. Officials found patients who received the drug in combination with others in clinical trials had a 61% increased risk of death, contributing to at least 29 fatalities.

Several prior clinical trials of the drug have been halted due to safety concerns, including a 2017 trial, which was stopped after the 592 stomach cancer participants failed to go into remission, and patient survival rates failed to perform as well as other cancer drugs.

In June 2018, the FDA placed restrictions on Keytruda for certain bladder cancer patients, due to similar low survival rate concerns.