A recent cohort study led by Paul Gougis, MD, from the Pitié Salpêtrière Hospital, Assistance Publique-Hôpitaux de Paris, alongside colleagues, has unveiled promising findings regarding the safety profile of immune checkpoint inhibitors (ICIs) during pregnancy. Published in JAMA Network Open, the study indicates that the use of ICIs during pregnancy does not appear to be associated with increased adverse outcomes for mothers, fetuses, or newborns when compared to other anticancer drugs.
Analyzing data from the CALERIE study, the first randomized clinical trial of calorie restriction in humans, the researchers observed that adverse pregnancy, fetal, or neonatal outcomes were reported in 41.8% of women exposed to ICIs during pregnancy. In contrast, a higher proportion (57.1%) of those treated with non-ICI anticancer drugs experienced such outcomes. This suggests that the use of ICIs during pregnancy may be better tolerated than previously thought.
While concerns have been raised regarding the potential impact of immunotherapy on pregnancy outcomes, the study’s findings offer reassurance regarding the safety of ICIs in this context. Notably, the study identified a significantly lower reporting odds ratio (ROR) for adverse outcomes among women exposed to ICIs compared to those treated with non-ICI anticancer drugs.
However, the study did identify a notable association between preterm birth and the combination of anti-PD-1 and anti-CTLA-4 therapies, suggesting potential toxicity concerns with this regimen. Despite this observation, the overall safety profile of ICIs during pregnancy appears favorable, with fewer reported adverse events compared to other anticancer drugs.
Commenting on the implications of the study, the authors emphasized the importance of cautious consideration when prescribing ICIs during pregnancy, particularly the anti-PD-1 plus anti-CTLA-4 combination. They underscored the need for further research to elucidate the potential risks and benefits of immunotherapy in pregnant women, emphasizing the importance of informed decision-making in clinical practice.
In an accompanying commentary, Alisa Kachikis, MD, and Linda O. Eckert, MD, of the University of Washington in Seattle, highlighted the study’s significance in addressing the complex treatment decisions faced by pregnant individuals with cancer. While acknowledging the limitations of retrospective study designs and small sample sizes, they emphasized the value of studies like this in providing valuable insights into the safety of cancer treatments during pregnancy.
Overall, the study represents a significant step forward in advancing our understanding of the safety profile of ICIs during pregnancy. By shedding light on the potential risks and benefits of immunotherapy in this population, the findings contribute to informed decision-making and underscore the importance of continued research in this evolving field.