LONDON -- For patients with chronic plaque psoriasis, phototherapy with long-wave ultraviolet light, despite its poorer safety record, combined with a psoralen-class drug, may be a better choice than short-wave UV therapy, researchers here said.
LONDON, July 17 -- For patients with chronic plaque psoriasis, phototherapy with long-wave ultraviolet light, despite its poorer safety record, combined with a psoralen-class drug, may be a better choice than short-wave UV therapy, researchers here said.
In patients with lighter skin (types I through IV), the psoralen-UV-A (PUVA) therapy achieved better clearance rates with fewer treatments compared with short-wave therapy, said Sami S. Yones, M.Sc.. F.C.D., of the St. Thomas Hospital here.
The combination also achieved longer periods of remission, Dr. Yones and colleagues said in the July issue of Archives of Dermatology.
The double-blind study involved 88 patients with chronic plaque psoriasis. Of these, 71 had skin types I though IV (lighter skin) and 17 had types V or VI (darker skin). Half were randomized to receive twice-weekly PUVA treatments including the drug Deltapsoralen (8-methoxypsoralen), and half received short-wave UV therapy with a look-alike placebo.
Both treatments achieved low psoriasis clearance rates in patients with darker skin, so the researchers focused on the 71 patients with lighter skin types. In this patient group, PUVA cleared psoriasis in significantly more patients compared with short-wave treatment, (85% versus 65%; P=.02).
The median number of treatments required until clearance was also significantly lower in the PUVA group (17 versus 28.5; P<.001).
At six months of follow-up, 68% of the PUVA group remained in remission, compared with 35% of the short-wave group (P=.02).
However, PUVA was associated with significantly more erythema than short-wave treatment (49% of patients versus 22%; P=.004). In addition, two patients switched to another drug because of nausea, a known side-effect of PUVA therapy, the scientists said.
Previous research has established that PUVA has a tendency to be associated with skin cancer after 160 to 200 lifetime treatments, the researchers said. In addition, the treatment requires the use of eye protection, cannot be used during pregnancy, and cannot be used in patients with hepatic impairment, they added.
However, the current results suggest that PUVA "tends to clear psoriasis more reliably, with fewer treatments, and for longer and should, therefore, still be used in appropriate patients," they concluded.