PUVA Treatment Of Psoriasis Research Articles

A randomized comparison of narrow-band TL-01 phototherapy and PUVA photochemotherapy for psoriasis

Background: Although PUVA treatment of psoriasis is more effective than conventional or broad-band UVB phototherapy, two small studies have suggested that narrow-band or TL-01 phototherapy may have a therapeutic effect equal to PUVA. If confirmed, this would be of considerable importance as TL-01 therapy is likely to be considerably safer in the long term than PUVA. Objective: The purpose of this study was to compare PUVA with narrow-band (TL-01) phototherapy in psoriasis. Methods: We studied 100 patients with plaque-type psoriasis who were randomly allocated to twice-weekly treatment with PUVA or narrow-band UVB. Results: Clearance of psoriasis was achieved in a significantly greater proportion of patients treated with PUVA (84%) than with TL-01 (63%) ( P = .018), and with significantly fewer treatments (median number of treatments for clearance with PUVA, 16.7; with TL-01, 25.3; P = .001). Only 12% of those treated with TL-01 were clear of psoriasis 6 months after finishing treatment compared with 35% for PUVA ( P = .002). Conclusion: When given twice weekly, PUVA is more effective for psoriasis than narrow-band UVB phototherapy. (J Am Acad Dermatol 1999;41:728-32.)

Comparison of psoralen-UVB and psoralen-UVA photochemotherapy in the treatment of psoriasis

Background: PUVA treatment of psoriasis is usually given with broad-band fluorescent UVA lamps. Narrow-band UVB exposure after oral methoxsalen has been shown to achieve a greater therapeutic response in psoriasis than identical UVB exposure given without psoralen. Objective: The purpose of this study was to compare conventional PUVA with psoralen-UVB therapy in psoriasis. Methods: We studied 100 patients with plaque-type psoriasis who were randomly selected to receive either conventional psoralen-UVA or psoralen-UVB treatment. Results: No significant difference was found between the two treatments in the proportion of patients whose skin cleared during treatment or in the number of exposures required for clearance of psoriasis. As expected, the cumulative UV dose for clearance was smaller in the group treated with UVB compared with those receiving UVA. Side effects and disease status at 3 months after the end of treatment were similar for the two groups. Conclusion: Psoralen-UVB treatment of psoriasis is as effective as conventional PUVA. The mechanism of psoralen–311 nm UVB action on psoriasis requires study to predict the long-term safety of this treatment. (J Am Acad Dermatol 1997;36:577-81.)

UVB and PUVA treatment of psoriasis and atopic dermatitis guided by skin reflectance measurements

UVB and PUVA treatment of psoriasis and atopic dermatitis guided by skin reflectance measurements

Erythemal and therapeutic response of psoriasis to PUVA using high-dose UVA.

In PUVA treatment of psoriasis, clinical observation suggests that uninvolved skin is more susceptible to PUVA erythema than lesions of psoriasis. If this is the case, then the efficacy of PUVA treatment might be increased by using localized high-dose UVA restricted to lesional skin. We have therefore studied the erythemal and therapeutic response of psoriasis to PUVA using high-dose UVA and, for comparison, the erythemal response to UVB. In 14 patients, an area of psoriasis and adjacent uninvolved skin were exposed to a series of UVA doses (350 +/- 30 nm, 1-16J/cm2), using an irradiation monochromator. Six other patients were similarly phototested with a series of UVB doses (300 +/- 5 nm, 20-112 mJ/cm2) to both uninvolved and lesional skin. Erythema was judged visually at 72 h for psoralen-UVA, and at 24 h for UVB, and measured using a scanning laser-Doppler velocimeter. In 10 patients, PUVA therapy using high-dose UVA was subsequently given to lesional skin (8-16J/cm2 twice weekly) in addition to conventional whole-body PUVA. For psoralen-UVA, the minimal phototoxic dose within psoriasis was increased by a factor of 4 compared with non-lesional skin (P < 0.01, Wilcoxon signed-rank test). For UVB, the minimal erythema dose within psoriasis was higher than that for non-lesional skin (medians > 112 and 28 respectively, P < 0.05). Laser-Doppler measurements confirmed that the reduced erythemal sensitivity was not due to masking of response by pre-existing increased blood flux within psoriasis.(ABSTRACT TRUNCATED AT 250 WORDS)

Response of psoriasis to twice weekly PUVA.

In the U.K., PUVA treatment for psoriasis is usually given three times weekly, with the starting dose of UVA chosen according to the skin type of the patient. Observations on the time-course and dose-response characteristics of PUVA erythema suggest that larger doses of UVA could be used safely, provided that the frequency of PUVA treatment is reduced. We have examined this by treating 100 patients with chronic plaque-type psoriasis with a PUVA protocol in which treatment using oral 8-methoxypsoralen was given twice weekly, with the starting dose of UVA based on each patient's minimal phototoxic dose, and with weekly UVA dose increments calculated as a percentage of the dose used in the previous treatment. Clearance of psoriasis was achieved in 92% of patients. The median number of treatments required for clearance was 12, and the median cumulative UVA dose for clearance was 52J/cm2. Although erythema occurred at some stage during the course of PUVA in 48% of patients, in only 16% of cases was the erythema of sufficient intensity to result in more than one treatment being missed. These results compare favourably with previous studies in which treatment was given three or four times weekly. Thus, twice weekly PUVA treatment for psoriasis is at least as effective as treatment given more frequently, and may be safer, as lower cumulative UVA doses are required for clearance. It also allows for more efficient operation of a PUVA unit and is more convenient for patients.

PUVA treatment of psoriasis in the United Kingdom

Information concerning the operation of 134 PUVA units in 96 dermatology centres in the U.K. was collected by a postal questionnaire. The most common protocol was to give PUVA three times weekly in the treatment of psoriasis, and to choose the initial dose of UVA according to skin type. However, the initial UVA dose encompassed a range of five or more within each skin type.

Lymphopenia and Decrease in the Total Number of Circulating CD3+ and CD4+ T Cells during ‘Long-Term’ PUVA Treatment for Psoriasis

The relationship between high-dose PUVA treatment in psoriatic patients and peripheral T lymphocyte subsets (total number and percentage) has been studied. Of the two groups of patients considered, the first included 19 patients, all affected by chronic, progressively worsening psoriasis; they had never been previously treated by photochemotherapy. The second group included 13 psoriatic patients, who had received an average cumulative dose of 2,007.69 +/- 1,191.05 J/cm2. The 'long-term' PUVA-treated group was assessed while undergoing maintenance therapy. No significant differences were found between untreated patients and healthy controls for any of the parameters considered. A significant reduction (p less than 0.05) in the total number of lymphocytes in long-term PUVA-treated patients both versus untreated patients and controls was found. Furthermore, long-term PUVA-treated patients showed a significant reduction (p less than 0.05) in the percentage of lymphocytes as compared with controls. The reduction in the total number of CD3+ and CD4+ T cells was, moreover, significant (p less than 0.05) as compared with untreated patients. The impairment of circulating CD3+ and CD4+ T cells (total number) was only on the borderline of statistical significance vis-à-vis controls. These findings suggest the usefulness of a careful assessment of circulating T lymphocyte subsets in patients who undergo long-term PUVA therapy.

A modified dosage schedule for increased efficiency in PUVA treatment of psoriasis.

Ten patients with chronic widespread plaque psoriasis, all of whom had previously completely cleared and suffered a subsequent widespread relapse after conventional PUVA therapy, were treated with a modified UVA dosage schedule, with psoralen formulation and dosage unchanged. Initial and incremental UVA doses were maximized to near-erythemogenic levels as determined by weekly testing for minimal phototoxic dose (MPD), treatment being given three times a week. A comparison of complete psoriasis clearing between the modified treatment and the last PUVA course showed a geometric mean reduction in treatment duration of 55% (P less than 0.001) for a similar number of treatments each week, and a cumulative UVA dose of 31% (P less than 0.05), representing a reduction in treatment duration from 9.1 to 4.1 weeks and cumulative UVA dose reduction of 100.8 to 69.9 J/cm2. Such an improvement in efficiency permits a marked increase in treated patient numbers for the same cost, and is more convenient. The reduction in the total cumulative UVA dose given as larger individual doses also seems likely to lead to a lower incidence of cutaneous long-term, especially carcinogenic, adverse effects.

Plasma levels of 8-methoxypsoralen and phototoxicity studies during PUVA treatment of psoriasis with meladinin tablets

A new tablet formulation of 8-methoxypsoralen was used in PUVA treatment for psoriasis. The 8-Mop plasma level showed a maximum at about 1 hour after ingestion (mean values: 1/2 hr, 284 microgram/1; 1 hr, 275 microgram/1; 1 1/2 hr, 198 microgram/1; 2 hrs, 129 microgram/1). Phototoxicity tests showed the optimal time for exposure to be about 1 hour after peroral intake of 8-MOP.