Dr XYZ a Dermatologist, is having a patient of Bullous Pemphigoid with elevated IgE level. He wants to start OmaliRel & RituxiRel RN to this patient. He has the following doubts 1. Should he give omalirel & RituxiRel RN to this patient at a time or start with either of them & then give another one ? 2. Vaccination prior to starting this therapy ? 3. Can he add ImmunoRel during this therapy as he suspects drop in immunity ?
omalizumab Bullous Pemphigoid elevated IgE treatment protocol
Management of Bullous Pemphigoid
Page 11
rituximab Bullous Pemphigoid dosing protocol combination therapy vaccination immunoglobulin
Management of Bullous Pemphigoid
Page 16
Drug Name Decoder: OmaliRel = Omalizumab (anti-IgE mAb) | RituxiRel = Rituximab (anti-CD20 mAb) | ImmunoRel = Intravenous Immunoglobulin (IVIg)
| Parameter | Rationale |
|---|---|
| Omalizumab first | This patient has elevated IgE — the defining biomarker that makes omalizumab the most targeted first choice. It is an anti-IgE mAb that directly addresses the IgE-mediated pathogenic axis in BP. |
| Mechanism fit | BP with high IgE has significant IgE-BP180 autoantibodies driving mast cell/eosinophil activation. Omalizumab neutralizes free IgE, reducing urticarial lesions and blister formation. |
| Rituximab timing | Rituximab (anti-CD20, B-cell depleter) is reserved for moderate-to-severe, refractory BP not adequately controlled by corticosteroids ± adjuvants. It should be added if the disease remains active despite omalizumab + standard therapy. |
| Safety rationale | Running both simultaneously unnecessarily stacks immunosuppression in a potentially older, comorbid BP patient, increasing infection risk without established added benefit from concurrent initiation. |
Practical algorithm:
- Start Omalizumab (300 mg SC q4 weeks, dose adjusted per IgE level/weight) + optimize topical/systemic corticosteroids
- Reassess at 12–16 weeks
- If inadequate control → add Rituximab (1000 mg IV × 2 doses, 2 weeks apart — RA protocol; or 375 mg/m² × 4 weekly — lymphoma protocol)
| Vaccine | Type | Timing Before Rituximab |
|---|---|---|
| Pneumococcal (PCV15/PCV20 or PPSV23) | Inactivated | ≥2–4 weeks prior |
| Influenza (seasonal) | Inactivated | ≥2 weeks prior |
| COVID-19 | mRNA (inactivated) | ≥2 weeks prior |
| Hepatitis B (if non-immune) | Inactivated | ≥2 weeks prior |
| Zoster (Shingrix) | Recombinant subunit | ≥2–4 weeks prior |
| Tdap | Inactivated | ≥2 weeks prior |
| Live vaccines (MMR, VZV live, Yellow Fever) | CONTRAINDICATED during and for months after rituximab | Must be given ≥4 weeks before OR deferred |
⚠️ Screen for Hepatitis B (HBsAg, anti-HBc, anti-HBs) before rituximab — HBV reactivation is a black-box warning. If HBsAg+ or anti-HBc+, antiviral prophylaxis (entecavir) is mandatory.
| Aspect | Details |
|---|---|
| IVIg in BP | Has level 1 evidence (RCT) — used as add-on therapy in BP patients with no improvement on prednisolone ≥0.4 mg/kg/day. Effect showed a trend toward benefit, though did not reach statistical significance in one RCT (Amagai et al., J Dermatol Sci 2017, p. 11). |
| Immunoglobulin replacement post-rituximab | Rituximab can cause secondary hypogammaglobulinemia (IgG depletion) with prolonged use. If serum IgG falls <4–5 g/L or patient develops recurrent serious infections → IVIg replacement is clinically indicated and appropriate. |
| Interaction with Omalizumab | IVIg is not contraindicated with omalizumab. The two work via entirely different mechanisms. |
| Timing consideration | If starting IVIg for immunoglobulin replacement (not disease control), dose is lower: 0.4–0.5 g/kg/month. For BP disease control, the dose used in trials was 2 g/kg per cycle. |
| Monitoring | Check serum IgG levels before and during rituximab therapy. Also monitor CBC, CD19/CD20 counts, and infection events. |
⚠️ Caution in elderly BP patients: IVIg carries risk of acute renal failure, thromboembolism, and hyperviscosity — especially in older patients with pre-existing renal or cardiovascular disease. Screen renal function and hydrate adequately.
| Question | Recommendation |
|---|---|
| Omalizumab + Rituximab simultaneously? | No — start Omalizumab first (IgE-driven BP); add Rituximab only if refractory |
| Vaccination before therapy? | Mandatory before Rituximab (≥2–4 weeks); screen HBV; avoid live vaccines; less critical for omalizumab alone |
| IVIg (ImmunoRel) during therapy? | Yes, appropriate — especially if post-rituximab hypogammaglobulinemia or recurrent infections; use with renal/cardiovascular caution in elderly |