What the FDA labels say about taking them together
Natalizumab and ocrelizumab
Ocrelizumab's FDA label of May 14, 2026 names natalizumab in its drug interactions section; the natalizumab labels PlainMeds reads (2) do not name ocrelizumab. The ocrelizumab label: “PML has occurred in OCREVUS-treated patients who had not been treated previously with natalizumab, were not taking any immunosuppressive or immunomodulatory medications associated with the risk of PML prior to or …”
Check it at the source: the natalizumab FDA label on DailyMed (effective March 21, 2025, Biogen Inc.); the ocrelizumab FDA label on DailyMed (effective May 14, 2026, Genentech, Inc.).
What does the natalizumab label say about ocrelizumab?
Natalizumab's label (effective March 21, 2025) and its 1 other brand-application label do not name ocrelizumab in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (TYSABRI), Biogen Inc., effective March 21, 2025 (SPL set c5fdde91-1989-4dd2-9129-4f3323ea2962), via openFDA; the full label on DailyMed
What does the ocrelizumab label say about natalizumab?
Ocrelizumab label, drug interactionsWhen switching from drugs with prolonged immune effects, such as daclizumab, fingolimod, natalizumab, teriflunomide, or mitoxantrone, consider the duration and mode of action of these drugs because of additive immunosuppressive effects when initiating OCREVUS [see Warnings and Precautions (5.2) ].
Ocrelizumab label, warnings and precautionsPML has occurred in OCREVUS-treated patients who had not been treated previously with natalizumab (which has a known association with PML), were not taking any immunosuppressive or immunomodulatory medications associated with the risk of PML prior to or concomitantly with OCREVUS, and did not have any known ongoing systemic medical conditions resulting in compromised immune system function.
Source: FDA drug label (OCREVUS), Genentech, Inc., effective May 14, 2026 (SPL set 9da42362-3bb5-4b83-b4bb-b59fd4e55f0d), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Natalizumab | Ocrelizumab | |
|---|---|---|
| Labeled for | Multiple sclerosis | n/a |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | n/a | n/a |
| Shortage now | No current entry | No current entry |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once