Can Dupixent (dupilumab) affect male fertility?

Dupilumab (Dupixent) and Male Fertility

Based on the available evidence, dupilumab (Dupixent) does not appear to harm male fertility, as animal studies showed no effects on fertility parameters including sperm analysis at doses up to 200 mg/kg/week in mice. 1

Evidence on Dupilumab and Male Fertility

The FDA drug label for Dupixent (dupilumab) specifically addresses fertility concerns in the nonclinical toxicology section. Animal studies using a homologous antibody against IL-4Rα (the same target as dupilumab) showed:

• No effects on fertility parameters
• No impact on reproductive organs
• No changes in sperm analysis
• No effects on menstrual cycle length

These findings were observed in sexually mature mice that received subcutaneous administration at doses up to 200 mg/kg/week 1, which represents a substantial safety margin compared to human therapeutic dosing.

Clinical Experience

There is limited clinical data specifically addressing male fertility with dupilumab use. A case series reported two men who successfully conceived children while on dupilumab treatment for atopic dermatitis, with no reported complications regarding their ability to conceive 2. While this represents a very small sample, it aligns with the preclinical safety data.

Mechanism of Action Considerations

Dupilumab is a monoclonal antibody that blocks the IL-4 receptor α subunit, inhibiting both IL-4 and IL-13 signaling pathways that drive type 2 inflammation 3. This mechanism primarily affects inflammatory pathways rather than hormonal or reproductive systems, which may explain why it does not appear to impact fertility parameters.

Risk Classification of Biologics and Targeted Therapies

According to fertility preservation guidelines, most targeted therapies (including monoclonal antibodies) are classified as having "unknown risk" to fertility 4. However, this general classification applies to cancer therapies and may not directly apply to dupilumab, which has specific safety data showing no impact on fertility parameters.

Practical Considerations

For men with concerns about fertility while using dupilumab:

1. The FDA label data provides reassurance that animal studies show no impact on fertility parameters 1
2. Unlike some medications that require discontinuation before conception (such as methotrexate or cyclophosphamide), there is no evidence suggesting dupilumab needs to be stopped before attempting conception 4
3. Dupilumab has a favorable overall safety profile across a wide range of doses 3

Monitoring Considerations

For men with fertility concerns who are using dupilumab:

• Standard fertility evaluation can be performed if there are concerns about fertility
• Semen analysis remains the cornerstone of male fertility assessment 4
• There is no evidence suggesting dupilumab requires special monitoring for fertility effects

Conclusion

The available evidence indicates that dupilumab does not harm male fertility based on preclinical animal studies and limited clinical experience. This is consistent with its mechanism of action and safety profile. For men with moderate-to-severe atopic dermatitis or other approved indications who require this medication, concerns about fertility impact should not be a barrier to treatment.