Pemphigus and pemphigoid are chronic illnesses that, with rare exception, do not improve without active treatment. Treatment approaches include a control phase and then a maintenance phase, with the possibility of complete remission or disease relapse (flare).
Current consensus of disease outcomes during treatment are (y):
- Baseline: defined as the day that therapy is started.
- Control of disease activity: defined as the time at which new lesions cease to form and established lesions begin to heal. The expected interval of time to reach the control of disease activity is on the order of weeks.
- End of the consolidation phase: defined as the time when the majority of lesions have healed, and the clinician feels it is possible to taper steroids. The timeframe varies by patient.
- Late Endpoints of disease activity are identified as complete remission off therapy: defined as the absence of new or established lesions while the patient is off all systemic therapy for at least two months.
- Complete remission on therapy: defined as the absence of new or established lesions while the patient is receiving minimal therapy.
In addition (y):
- Minimal therapy is defined as less than, or equal to, 10 mg/day of prednisone (or the equivalent) and/or minimal adjuvant therapy for at least two months.
- Minimal adjuvant therapy is defined as half of the dose required to be defined as treatment failure (see below).
- A partial remission off therapy: defined as the presence of transient new lesions that heal within one week without treatment and while the patient is off all systemic therapy for at least two months.
- A partial remission on minimal therapy: defined as the presence of transient new lesions that heal within one week while the patient is receiving minimal therapy, including topical steroids.
- Relapse/Flare. A relapse of disease and a flare of disease are synonymous. They are defined by the appearance of 3 or more new lesions a month that do not heal spontaneously within 1 week, or by the extension of established lesions in a patient who has achieved disease control.
- Treatment Failure: Failure of therapy is defined as the failure to control disease activity (i.e., relapse/flare, or continued development of new lesions, continued extension of old lesions, or failure of established lesions to begin to heal) with full therapeutic doses of systemic treatments. This includes 3 weeks of therapy on 1.5 mg/kg/day prednisone equivalent with or without
- Cyclophosphamide 2 mg/kg/day for 12 weeks
- Azathioprine 3 mg/kg/day for 12 weeks (if TPMT level is normal)
- Methotrexate 20 mg/week for 12 weeks
- Mycophenolate mofetil 3 gm/day for 12 weeks
The methotrexate and mycophenolate mofetil doses are based on an individual of 75kg. These doses reflect the fact that additional therapies may be beneficial and a consideration for patients who are considered to be a failure of therapy.