Refrigerated Storage


300mg Concentrate for solution for infusion

Contact Biogen in all cases where deviation from the recommended storage conditions has occurred. Refer to the current BNF for company contact details.

Please also refer to the manufacturer’s product literature for recommended storage information at

19 March 2021
London MI service

Lactation Safety Information

No alternative for stage of multiple sclerosis for which used
Limited published evidence shows variable levels in breast milk, ranging from undetectable to moderate.
The long half-life increases the risk of accumulation
Natalizumab is a very large protein molecule which is likely to be degraded in the infant’s gastro-intestinal tract. Very limited published evidence shows infant serum levels are undetectable.
As a precaution, the infant should be monitored for signs of infection, changes in feeding and poor weight gain.
Breastfeeding appears to have beneficial effects to a mother with multiple sclerosis
15 March 2022

New Medicines

TysabriRelapsing-remitting multiple sclerosis (MS) - subcutaneous injection


New formulation

Development and Regulatory status

Approved (Licensed)
Not approved
April 2021
Apr 21Launched in UK. Price for two 150mg pre-filled syringes = £1,130 [9,10].
Apr 21FDA does not approve the company's supplemental Biologic License Application for subcutaneously delivered natalizumab for the treatment of relapsing multiple sclerosis. Rationale has not been publicly released. [8]
Apr 21Approved in UK [7].
Apr 21Approved in EU [6]
Jan 21Current licensed indication for Tysabri IV is as use single disease modifying therapy in adults with highly active relapsing remitting multiple sclerosis for patients with highly active disease despite a full and adequate course of treatment with at least one disease modifying therapy (DMT) or patients with rapidly evolving severe relapsing remitting multiple sclerosis defined by 2 or more disabling relapses in one year, and with 1 or more Gadolinium enhancing lesions on brain MRI or a significant increase in T2 lesion load as compared to a previous recent MRI [6].
Jan 21Recommended for EU approval by CHMP - approval covers the same indications as the original product. Treatment [...] is to be initiated and continuously supervised by specialised physicians experienced in the diagnosis and treatment of neurological conditions, with timely access to MRI. Home treatment is not recommended [5].
Oct 20Currently pre-registration in the EU. Has been filed using centralised procedure [3].


A selective adhesion-molecule inhibitor and binds to the α4-subunit of human integrins, which is highly expressed on the surface of all leukocytes, with the exception of neutrophils. SC formulation, dosed every 4 weeks.
MS estimated prevalence is 190 cases per 100,000 population. MS is more than twice as common in females than males. The highest prevalence for MS occurs in the 60 to 69 years age group for both sexes. The MS estimated incidence in England is between 8 and 11 new cases per 100,000 population [1].
Relapsing-remitting multiple sclerosis (MS) - subcutaneous injection
Subcutaneous injection

Trial or other data

Oct 14PII REFINE study completes [2].
Aug 11PII REFINE study to explore the effects of multiple regimens of natalizumab on disease activity and safety in participants with relapsing-remitting MS (RRMS) starts (NCT01405820). The study will explore dosing of natalizumab by subcutaneous and intravenous routes. Participants will be randomly assigned to 1 of 6 dosing regimens, blinded to natalizumab dose, but not route, for 60 weeks of treatment. 290 adults will be recruited in Belgium, Germany, France, Italy and Spain. Primary outcome is Cumulative number of combined unique active lesions (sum of the number of new gadolinium (Gd)-enhancing lesions and new or newly enlarging T2 hyperintense lesions not associated with Gd-enhancement on T1 weighted scans) based on brain magnetic resonance imaging (MRI) scans up to week 60 [2].

Evidence based evaluations