***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Forty‐eight patients with symmetrical chronic plaque psoriasis affecting the limbs were recruited for a single‐blind right/left within patient study to assess the effect of combining occlusion with topical calcipotriol .  Subjects were r and omized into two groups . Sites of similar severity on opposing limbs were selected as target areas . The first ( group A ) treated one side with calcipotriol alone and the opposite side with calcipotriol plus occlusion . The second ( group 13 ) treated one side with placebo plus occlusion and the opposite side with calcipotriol plus occlusion . In group A the mean improvements were 40 % ( P < 0·001 ) for calcipotriol alone and 61 % ( P < 0·001 ) for calcipotriol plus occlusion . In group B , occlusion plus calcipotriol result ed in a mean 62 % improvement ( P < 0·001 ) while occlusion plus placebo produced no significant change . The combination of calcipotriol plus occlusion was significantly better than calcipotriol alone ( P < 0·005 ) . The results indicate that occlusion improves the response to calcipotriol by enhancing its penetration . Indices of calcium metabolsm remained unchanged throughout the study Ro 10 - 9359 is a retinoic acid derivative , selected for study because of a better tolerance than retinoic acid , shown in animal experiments . Doses of 25 mg b.i.d . , 25 mg t.i.d . and 50 mg b.i.d . were administered orally to 27 patients suffering from severe chronic generalized psoriasis . The clinical efficacy was evaluated by means of a new index , psoriasis area and severity index ( PASI ) based on severity and area of psoriatic lesions . At doses of 25 mg t.i.d . or 50 mg b.i.d . Ro 10 - -9359 proved to be an extremely potent antipsoriatic drug . A more than 90 % reduction of psoriatic lesions could be seen in 10 patients out of 20 after 4 - 8 weeks of treatment . This good effect lasted about 5 weeks after treatment . Side effects were frequent , but mostly mild and completely reversible after termination of treatment BACKGROUND Although potent , topical corticosteroids offer effective and rapid healing of psoriatic lesions .  Their long term use is limited because of the risk of side effects . Calcipotriol is safe for long-term treatment , but its initial efficacy is lower than with topical corticosteroids . OBJECTIVES To investigate whether 2 weeks of treatment with clobetasol propionate 0.05 % ointment bd followed by 4 weeks of treatment with calcipotriol 50 microg/g bd would offer therapeutic advantages over 6 weeks of continuous treatment with calcipotriol . METHODS Forty-nine patients with moderate to severe plaque psoriasis were recruited from five centres in Norway . In a r and omised , double-blind , right- versus left-side comparison , ointments were applied to two symmetrically-located areas . RESULTS Two weeks of treatment with clobetasol propionate produced a significantly greater decrease in total symptom score ( combined scores of erythema , in duration and scaling ) than calcipotriol treatment ( P < 0.0001 ) . This improvement on the clobetasol propionate-treated side of the body was maintained throughout a subsequent 4-week treatment period when calcipotriol was applied to both sides of the body ( P < 0.0001 ) . The superiority of the clobetasol propionate followed by calcipotriol treatment was maintained during a 4-week , treatment-free , observation period . Treatments were well tolerated with no rebound effect . CONCLUSIONS Clobetasol propionate ointment bd for 2 weeks followed by treatment with calcipotriol ointment bd for 4 weeks was superior to calcipotriol ointment alone in the treatment of plaque psoriasis In 10 in- patients with chronic plaque psoriasis , the antipsoriatic effect of MC903 , a new synthetic analogue of vitamin D was evaluated . In each patient two symmetrical located psoriatic plaques were selected for the study . Topical treatment with MC903 cream ( containing 1.2 mg MC903 per g cream ) was compared with placebo cream in a double-blind , controlled , left-right , r and omized way during 6 weeks of therapy . Compared with baseline , the clinical ( erythema , scaling and infiltration ) improvement was significant after 1 week of therapy with MC903 cream , while lateral comparison showed MC903 cream significantly better than cream base after 4 weeks of therapy ( p less than 0.05 ) . Measurements of skin blood flow by the laser Doppler technique in evaluating the disease activity was not superior to the clinical assessment s. In 3 patients the psoriatic lesions treated with MC903 cream  cleared completely during 6 weeks of therapy . No essential adverse reactions were observed . MC903 has a potent effect on cell proliferation and cell differentiation , but has minimal effect on calcium metabolism . It is concluded that this synthetic vitamin D analogue is potentially useful in the treatment of psoriasis The effect of the non‐calciotropic vitamin D3 analogue MC 903 on psoriasis vulgaris was assessed in a double‐blind , placebo controlled trial in 30 patients . Lesions on one side of the body were treated for 6 weeks with a cream containing 10 μ/g , 33 μg//g or 100 μg/g MC 903 and lesions on the other side were treated with the cream base alone , according to a r and omized design . Nine of the 10 patients in each treatment group completed the study . MC 903 cream gave a statistically significant decrease in erythema , thickness and scaling of the lesions , compared with the control . Overall assessment of psoriasis after 6 weeks showed moderate or excellent improvement in two of nine patients treated with 10 μg/g , in five of nine patients treated with 33 μ/g , and in seven of nine patients treated with 100 μ/g MC 903 . Placebo treatment showed a moderate improvement in only one of the 27 patients .  The histopathological picture of the psoriatic lesions corresponded with the clinical changes . The patients reported no adverse reactions , and laboratory tests did not show any significant changes ; in particular there was no change in serum calcium levels . These results suggest that the vitamin D3 analogue MC 903 is an effective and safe topical treattnent for psoriasis Topical treatment of psoriasis with calcipotriol has been proven effective . The efficacy of calcipotriol has been compared to that of topical corticoids in a number of studies using subjective visual scoring systems such as the PASI index . The purpose of this study was to compare , with objective data , the efficacy of calcipotriol and clobetasol propionate 0.05 % in the treatment of plaque type psoriasis .  Transepidermal water loss ( TEWL ) and laser Doppler velocimetry ( LDV ) were used to monitor restoration of water barrier and normalization of blood flow , respectively , in psoriatic plaques of the limbs of 24 male patients during 3 weeks of treatment . Data were compared to subjective evaluation using the PASI index of the same areas . Significant differences were recorded during treatment in both groups . The results correlated well with the PASI score .  Clobetasol was faster in restoring barrier function than calcipotriol . However , no significant differences were detected between the two groups . The use of vitamin analogues may be effective in the topical treatment of psoriasis by normalizing skin biophysical parameters and minimizing the risks of side-effects induced by potent topical corticoids 
    Output:
    
CONCLUSIONS Calcipotriol is an effective treatment for mild to moderate chronic plaque psoriasis , more so than calcitriol , tacalcitol , coal tar , and short contact dithranol .
Only potent topical corticosteroids seem to have comparable efficacy at eight weeks .
Although calcipotriol caused more skin irritation than topical corticosteroids this has to be balanced against the potential long term effects of corticosteroids .
Skin irritation rarely led to withdrawal of calcipotriol treatment .