Table 3.

Expert recommendations on treatment indications and regimens

Group	aGvHD	cGvHD
ASFA [10]	Indication: salvage treatment after failure of first-line therapy Regimen: 1 cycle (2 treatments typically on 2 consecutive days) performed weekly until disease response and then tapered to every other week before discontinuation	Indication: steroid-refractory or steroid-dependent extensive cGvHD Regimen: 1 cycle weekly for 4 weeks (or consider biweekly if treating only mucocutaneous cGVHD) and then 1 cycle every 2 weeks or for at least 8 weeks (assess at 2–3 monthly intervals), continue to maximum response every 2–4 weeks with tapering
German Working Group on Bone Marrow and Blood Stem-Cell Transplantation [42, 43]	Indication second-line treatment Regimen: initially 3×/week, then 2×/week until resolution	Indication: salvage therapy after first-line therapy Regimen: −
European Dermatology Forum [9]	Indication: no response to first-line therapy with corticosteroids at 2 mg/kg/day, defined as progression of aGvHD after ≥3 days of corticosteroid treatment or lack of response after ≥7 days of corticosteroids Regimen: 2–3 treatments per week with cessation upon achievement of a complete response	Indication: second-line treatment for steroid-refractory patients (progression on prednisone at 1 mg/kg/day for 2 weeks, stable disease on at least 0.5 mg/kg/day for 4–8 weeks and inability to taper steroids below 0.5 mg/kg/day) Regimen: 1–2 cycle(s) of ECP every 1–2 weeks for 3 months; thereafter, intervals can be increased depending on the type of lesions, extension, and the clinical response; if cGvHD progress consider a change in the treatment strategy
United Kingdom Photopheresis Society [25]	Indication: no response to first-line therapy with corticosteroids at 2 mg/kg/day, defined as progression of aGvHD after ≥3 days of corticosteroid treatment or lack of response after ≥7 days of corticosteroids Regimen: 2–3 treatments per week with cessation upon achievement of a complete response	Indication: second-line treatment in skin, oral or liver cGvHD, third-line treatment for other organs Regimen: 2 consecutive days every week with minimum assessment after 3 months
BCSH/BSBMT [26, 44]	Indication: second-line treatment of aGvHD grade III/IV Regimen: optimal schedule and duration not defined	Indication: second-line treatment in skin, oral, and liver cGvHD, may also be considered as third-line treatment for cGvHD involving other organs Regimen: fortnightly-paired treatments for a minimum assessment period of 3 months