Natalizumab

Blueteq
Natalizumab requires Blueteq initiation and annual updating.

Pregnancy
St George's usual practice - 8 weekly treatment through pregnancy up to 32 weeks. Restart after delivery and 8 weekly during breast feeding

When someone becomes pregnant while on natalizumab: Leonora's comments Sep 2021
I will only refer to the scenario of a patient with RRMS who is on Natalizumab and who falls pregnant (not necessary planning pregnancy).

Given the high risk of rebound disease, I recommend:

1)      Continuing on Natalizumab on a reduced frequency, every  6-8 weeks as long as the last infusion is given at week 34 (and not 32)

a.       Why? In order to reduce the risk of rebound disease in the mother (more commonly seen 12 weeks or more after the last dose of Natalizumab) and reduce the risk of thrombocytopaenia in the newborn

2)      Continue the PML surveillance MRI scanning avoiding contrast and ideally avoiding the 1st trimester especially if this is the 1st pregnancy and the patient is JCV –ve

a.       If patients are JCV positive, I use this chance to consider switch of therapies  so coordinate pre-screening and CSF examination if required so there isn’t a prolonged gap between the last dose of Natalizumab and the start of the new DMT (ideally no more than 4-6 weeks – all dependant on the health of the mother and on whether mother will be breastfeeding or not).

b.      JCV screening continues to be done every six months

3)      Establish beforehand on whether patient decide to breastfeed or not

a.       If patient decide to not breastfeed, then I resume regular Natalizumab infusions

i.      Some patients are happy to go for EID (extended interval dosing 6-8 weeks) some like to go back to 4 weekly

b.      If patient decide to breastfeed  they can do so for 2 weeks, so they have a gap of 8 weeks from the latest Natalizumab infusion

i.       I do however, given the benefit of the breastfeeding, share with the patient the following from the guidelines: Natalizumab is transferred to/crosses into breast milk and the amount increases with time. However, there are significant benefits of breastfeeding. Whilst the SmPC for Natalizumab states that it should be discontinued whilst breastfeeding, the panel believed that as the oral bioavailability is negligible, any transfer into breast milk is unlikely to result in systemic absorption by the baby

ii. So far I haven’t had any patient of mine that has breastfed whilst on Natalizumab

1.       I am aware that in some centres patients sign a consent form to continue Natalizumab whilst breastfeeding

c.       For patient that for a reason on another (especially for those that are JCV positive) I re-baseline them by doing a brain and spine MRI scan to assess for any rebound activity

i.      You do not want to end up needing to do a CSF examination to exclude PML on someone that might have rebound disease and the neuroradiologist says – cannot exclude PML!

Consent
Basil's example

Links

 * BNF entry
 * Summary of product characteristics (SmPC)
 * Cochrane review 2011