What is the treatment for a pemphigus (Pemphigus, a group of chronic blistering skin diseases) flare-up?

From the Guidelines

To treat a familial pemphigus flare-up, oral prednisolone at 1 mg/kg-1 per day (or equivalent) is recommended as the first-line therapy, with the dose increased in 50–100% increments every 5–7 days if blistering continues, as suggested by the British Association of Dermatologists' guidelines for the management of pemphigus vulgaris 2017 1. The treatment approach should prioritize reducing the severity of the flare-up while minimizing the risk of side effects.

• The initial dose of prednisolone can be adjusted based on the severity of the disease, with 0.5–1 mg/kg-1 per day recommended for milder cases 1.
• In cases where high doses of oral prednisolone are required (> 1 mg/kg-1), pulsed intravenous corticosteroids may be considered as an alternative or in addition to oral therapy 1.
• Once remission is induced and maintained, the dose of prednisolone should be tapered to 10 mg daily or less, with the aim of withdrawing treatment if possible, as indicated by the high rates of complete remission off-therapy reported in the guidelines 1.
• Adjuvant immunosuppressants such as azathioprine (2–3 mg/kg-1 per day) or mycophenolate mofetil (2–3 g per day) may be added to the treatment regimen to reduce the dose of corticosteroids required and minimize the risk of side effects 1.
• Rituximab, a monoclonal antibody targeting CD20, has shown promise as a treatment option for pemphigus, particularly in cases that are refractory to conventional therapy, and may be considered as a third-line treatment option 1.

From the FDA Drug Label

1. 5 Pemphigus Vulgaris (PV) RITUXAN is indicated for the treatment of adult patients with moderate to severe pemphigus vulgaris.

The treatment for familial pemphigus flare-up is not directly addressed in the provided drug labels. However, Pemphigus Vulgaris (PV) is mentioned, and rituximab is indicated for the treatment of adult patients with moderate to severe PV.

• Rituximab may be considered as a treatment option for familial pemphigus flare-up, but this is not explicitly stated in the drug labels.
• The decision to use rituximab for familial pemphigus flare-up should be made with caution and under the guidance of a healthcare professional, as the evidence is not directly applicable 2.

From the Research

Treatment Options for Familial Pemphigus Flare-Up

• Systemic corticosteroids remain the gold standard treatment for pemphigus vulgaris, with the goal of controlling the disease, preventing relapses, and avoiding adverse events associated with prolonged use 3
• Azathioprine and mycophenolate mofetil are considered first-line steroid-sparing treatments, with mycophenolate mofetil being less myelosuppressive and hepatotoxic than azathioprine 4, 5
• Rituximab is an effective treatment for recalcitrant pemphigus, particularly when other treatments fail to control the disease 3, 4

Management of Relapse

• If a patient relapses, options include increasing steroids back to the previous dose, adding an immunosuppressant if using steroid monotherapy, or replacing a first-line immunosuppressant with another if already on combination therapy 3
• A combination of immunoadsorption, rituximab, pulsed dexamethasone, and azathioprine/mycophenolate mofetil may induce a rapid and durable remission in severe, treatment-resistant pemphigus 4

Treatment Protocols

• The European Dermatology Forum recommends tapering prednisolone by 25% every 2 weeks after the consolidation phase, and a 5 mg reduction every 4 weeks when the dose is reduced to <20 mg 3
• A novel protocol treatment involving immunoadsorption, rituximab, pulsed dexamethasone, and azathioprine/mycophenolate mofetil has been shown to induce a fast and long-term remission in severe pemphigus, with an improved side-effect profile compared to daily use of corticosteroids 4

Immunosuppressive Therapies

• Immunosuppressive agents, such as azathioprine, mycophenolate mofetil, cyclophosphamide, methotrexate, and dapsone, are widely used as corticosteroid-sparing drugs in the treatment of pemphigus 6, 7, 5
• Newer therapies focus on blocking cell signaling events induced by pathogenic autoantibodies and/or targeting specific autoantibodies 7