Parenteral administration of 8-methoxypsoralen in photopheresis.
BACKGROUND
Extracorporeal photochemotherapy (EP) is used for the treatment of cutaneous T-cell lymphoma (CTCL), progressive systemic sclerosis (PSS), pemphigus vulgaris, and rheumatoid arthritis. During this procedure, the oral administration of the photoactive drug 8-methoxypsoralen (8-MOP) results in an unpredictable range of serum levels and in side effects limiting its efficacy.


OBJECTIVE
To circumvent this limitation, extracorporeally administrable 8-MOP (EX-8-MOP) was developed. It is administered directly to the leukocyte/plasma concentrate in the treatment bag of the EP apparatus before irradiation with UVA light.


METHODS
Efficacy, tolerance, and side effects of EX-8-MOP were evaluated in 108 consecutive treatments of 16 patients who had previously been treated with oral 8-MOP (91 treatments).


RESULTS
With EX-8-MOP constant drug levels for UV light exposure were obtained; for equivalent levels only a small fraction of the oral dose (1/250 to 1/500) was required with none of the side effects associated with oral 8-MOP. Effective and reproducible inhibition of lymphocyte proliferation and cell viability was attained. No difference in clinical efficacy could be observed.


CONCLUSIONS
EX-8-MOP eliminates the need for premedication and drug level monitoring of 8-MOP and should improve the effectiveness of EP.
Knobler
R M
RM
Department of Dermatology, University of Vienna, Austria.
Trautinger
F
F
Graninger
W
W
Macheiner
W
W
Gruenwald
C
C
Neumann
R
R
Ramer
W
W
D000284:Administration, Oral; D002214:Capsules; D002470:Cell Survival / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007263:Infusions, Parenteral; D007937:Leukapheresis; D008214:Lymphocytes / Q000187:drug effects / Q000473:pathology; D008730:Methoxsalen / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use*; D009325:Nausea / Q000139:chemically induced; D010778:Photochemotherapy / Q000379:methods*; D012871:Skin Diseases / Q000097:blood / Q000188:drug therapy*; D012878:Skin Neoplasms / Q000097:blood / Q000188:drug therapy*; D014839:Vomiting / Q000139:chemically induced
D002214:Capsules; D008730:Methoxsalen