5-Methoxypsoralen (Bergapten) for photochemotherapy. Bioavailability, phototoxicity, and clinical efficacy in psoriasis of a new drug preparation.
In a previous study we evaluated a microcrystalline preparation of 5-methoxypsoralen (5-MOP; Bergapten) for its photochemotherapeutic properties. Preliminary data indicated that the clinical efficacy of 5-MOP is comparable to that of 8-methoxypsoralen. 5-MOP appeared as a promising alternative photosensitizer for the management of psoriasis because of the almost complete lack of phototoxic and drug intolerance reactions that are frequently encountered in patients undergoing 8-MOP photochemotherapy. With a new liquid preparation of 5-MOP we have now extended our earlier investigation on a larger clinical scale and have correlated the clinical response with the bioavailability of the drug. Serum level determinations showed an absorption rate of only approximately 25% that of 8-MOP. When administered in the same dosage as 8-MOP, 5-MOP turned out to be significantly less effective; however, by doubling the oral dosage, comparable results in terms of clearing of psoriasis were obtained. Also with this high-dose 5-MOP regimen, no drug intolerance was noted and other side effects, such as severe erythema, pruritus, and nausea, occurred only rarely. We propose 5-MOP as a valuable alternative for photochemotherapy (PUVA) of PUVA-responsive diseases.
Tanew
A
A
Department of Dermatology I, University of Vienna, Austria.
Ortel
B
B
Rappersberger
K
K
Hönigsmann
H
H
D000078223:5-Methoxypsoralen; D001682:Biological Availability; D002986:Clinical Trials as Topic; D004334:Drug Administration Schedule; D006801:Humans; D008730:Methoxsalen / Q000009:adverse effects / Q000493:pharmacokinetics* / Q000627:therapeutic use; D011701:PUVA Therapy; D010787:Photosensitivity Disorders / Q000139:chemically induced*; D011565:Psoriasis / Q000188:drug therapy*; D011897:Random Allocation
D000078223:5-Methoxypsoralen; D008730:Methoxsalen