Ocrevus (ocrelizumab) is a medication primarily used to treat multiple sclerosis (MS), a chronic autoimmune disease affecting the central nervous system. When considering its impact on fertility, it is important to understand both the drug’s mechanism and the available evidence from clinical and animal studies.
Ocrevus works by targeting and depleting CD20-positive B cells, a type of immune cell involved in the autoimmune process of MS. Because it affects the immune system, concerns naturally arise about whether it might influence reproductive health or fertility in men and women.
**Effects on Female Fertility:**
There is limited direct human data on Ocrevus and female fertility. However, animal studies provide some insights. In studies with pregnant monkeys given high doses of ocrelizumab during organ development, there were observations of B-cell depletion in fetal lymphoid tissues and some adverse neonatal effects such as perinatal deaths and renal toxicity. Notably, these effects were seen at doses much higher than those used in humans. Importantly, no clear evidence showed that ocrelizumab caused long-term fertility impairment in female animals, but the neonatal complications suggest caution during pregnancy and reproductive planning.
In clinical practice, women of childbearing potential are advised to use effective contraception during treatment and for a period after the last dose, reflecting a precautionary approach due to the drug’s immune effects and the lack of extensive pregnancy safety data. MS itself can complicate pregnancy outcomes, but Ocrevus’s direct impact on female fertility remains unclear and is generally considered low risk if managed properly.
**Effects on Male Fertility:**
Animal studies have shown some concerning findings related to male reproductive organs. In neonatal monkeys exposed to high doses of ocrelizumab, reduced testicular weight was observed. This suggests a potential impact on testicular development at very high exposure levels. However, there is no direct evidence from human studies that Ocrevus impairs sperm production or male fertility.
Men receiving Ocrevus are generally counseled about potential reproductive risks, and contraception is recommended during treatment and for some time afterward. The lack of definitive human data means that any effect on male fertility is not well established but is considered unlikely at therapeutic doses.
**General Considerations:**
– Ocrevus’s mechanism of depleting B cells can theoretically affect immune regulation related to reproduction, but no direct impairment of fertility has been conclusively demonstrated in humans.
– Because Ocrevus can increase the risk of infections, including serious herpes virus infections, immune system changes during treatment might indirectly affect reproductive health or pregnancy outcomes.
– Women planning pregnancy are advised to discuss timing with their healthcare provider, as the drug’s effects on the fetus and newborn immune system are not fully understood. The recommendation is often to wait several months after the last infusion before attempting conception.
– MS itself can influence fertility and pregnancy outcomes, so distinguishing the effects of the disease from the medication is important.
– Current guidelines emphasize contraception during treatment and careful pregnancy planning rather than outright avoidance of pregnancy for all patients.
**Summary of Key Points:**
| Aspect | Evidence/Considerations |
|————————-|————————————————————|
| Female fertility | No direct human evidence of impairment; animal studies show fetal B-cell depletion and neonatal effects at high doses; contraception recommended during and after treatment. |
| Male fertility | Animal studies show reduced testicular weight at high doses; no clear human data; contraception advised. |
| Pregnancy risks | Potential neonatal immune effects; increased infection risk; pregnancy planning essential. |
| MS disease impact | MS itself can affect fertility and pregnancy outcomes, complicating assessment. |
| Clinical advice | Use contraception during treatment; consult healthcare provider for pregnancy planning. |
In essence, while Ocrevus has shown some effects on reproductive tissues in animal studies at high doses, there is no definitive evidence that it causes infertility in humans
