Bridge Therapy for MS Awaiting Ocrevus Approval
Continue the patient's current disease-modifying therapy (DMT) without interruption until Ocrevus is approved and can be initiated, as discontinuing effective MS treatment creates unnecessary risk of disease reactivation and breakthrough activity. 1
Recommended Bridge Strategy
If Patient is Currently on Any DMT
- Maintain the existing DMT without interruption until Ocrevus approval and initiation can occur 1
- Do not create a treatment gap, as this exposes patients to risk of disease reactivation during the transition period 1
- The concept of "bridge therapy" in MS specifically refers to maintaining disease control during transitions, not switching to a temporary alternative 2
If Patient is Treatment-Naive or Off Therapy
For patients with highly active or aggressive MS awaiting Ocrevus approval:
- Initiate interferon beta-1a (Avonex) as first-line therapy while awaiting Ocrevus approval, as it is FDA-approved for relapsing forms of MS and can be started immediately 3
- Alternative options include other moderate-efficacy DMTs (glatiramer acetate, dimethyl fumarate, teriflunomide) that can be initiated quickly without extensive insurance authorization delays 2
For patients with standard relapsing-remitting MS:
- Interferon beta-1a remains the most accessible bridge option with established safety profile 3
- These moderate-efficacy DMTs require minimal washout when transitioning to Ocrevus 2
Timing Considerations for Transition
Washout Requirements
- Interferon beta-1a to Ocrevus: No mandatory washout period required - can transition directly once Ocrevus is approved 2
- Most oral DMTs (dimethyl fumarate, teriflunomide, fingolimod) require minimal washout of 2-4 weeks before initiating Ocrevus 2
- Avoid using natalizumab or alemtuzumab as bridge therapy due to complex washout requirements and risk of carryover immunosuppression 4
Pre-Ocrevus Screening During Bridge Period
- Complete hepatitis B screening (surface antigen, core antibody, surface antibody) during bridge therapy period 4
- Administer live-attenuated vaccines at least 4-6 weeks before planned Ocrevus initiation 1
- Obtain baseline MRI with gadolinium, T2-weighted, and FLAIR sequences 1
Critical Pitfalls to Avoid
Do not create treatment gaps - The evidence consistently shows that discontinuing effective therapy or creating washout periods without clinical necessity increases risk of breakthrough disease activity and may result in irreversible disability accrual 1, 5
Do not use high-efficacy DMTs as bridge therapy - Agents like natalizumab, alemtuzumab, or rituximab create complex washout scenarios and potential for carryover effects that complicate Ocrevus initiation 4
Do not delay Ocrevus initiation unnecessarily - Once approved, transition promptly as early treatment with high-efficacy therapy like Ocrevus is associated with better long-term outcomes, with data showing 66.4% of patients maintaining no evidence of disease activity over 4 years when treated early 6
Rationale for This Approach
The 2025 ECTRIMS/EBMT guidelines emphasize early escalation strategies over traditional stepped care, particularly for patients with highly active disease 2. However, the concept of "bridge therapy" in MS refers to maintaining disease control during administrative delays, not switching to temporary alternatives that may compromise long-term outcomes 1.
Ocrevus demonstrates superior efficacy compared to interferon beta-1a, with 39% reduction in relapse rate and maintenance of no evidence of disease activity in 74.8% of patients over 96 weeks 5, 7. The key is preventing disease activity during the approval waiting period while minimizing complications during the eventual transition 1.