Psoriasis is a chronic inflammatory skin disease characterized by erythematous (red) patches and plaques. In some patients, psoriasis may be associated with comorbidities such as arthritis, obesity, diabetes, cardiovascular diseases, hyperlipidemia, or depression. Psoriasis lesions can occur on the scalp and face, in addition to all other areas of the body, causing considerable physical discomfort and psychosocial trauma from the stigma surrounding appearance defects.
More than 90% of patients with psoriasis have what is called psoriasis vulgaris, which is characterized by plaques, and less than 5% have the other varieties: arthritic psoriasis, pustular psoriasis, and erythrodermic psoriasis. The most common treatments for mild to moderate plaque psoriasis are topical corticosteroids and vitamin D3 analogs.
However, the long-term use of these topical steroids often causes various side-effects such as skin atrophy, hypo- or hyper-pigmentation, telangiectasia, and skin infections. And the long-term use of vitamin D3 analogs may add the requirement of interventions to regulate calcium and phosphate metabolism. These effects on the body are significant and there is a need for novel topical and systemic treatments for psoriasis.
In a study recently published in Chinese Medical Journal, scientists from renowned research institutes and hospitals across China, led by Prof. Jian-Zhong Zhang from Peking University People's Hospital, have met this need in part. They have reported that benvitimod, a novel non-steroid topical drug, is effective and safe for treating plaque psoriasis.
Speaking of their research journey, Prof. Zhang says, "Benvitimod (also known as tapinarof) is a small molecule that was first isolated from the bacterium Photorhabdus luminescens and was synthesized by late Genhui Chen and his team from Beijing Wenfeng Tianji Pharma. It took more than 20 years to study the mechanism of action, come up with the formulation, and evaluate the efficacy and safety of this compound in patients with psoriasis. It was hard work indeed."
In their study, Prof. Zhang and his colleagues carried out a double blinded, placebo controlled, phase III clinical trial in twenty-three dermatological centers in China to evaluate the safety and efficacy of topical benvitimod cream in patients with mild-to-moderate plaque psoriasis.
Six hundred and eighty-six adult patients with mild to moderate plaque psoriasis were included in this study. Patients were randomized to receive 1% benvitimod cream, 0.005% calcipotriol ointment--a standard treatment for plaque psoriasis--or a similar-looking "placebo." They were treated for 12 weeks. The efficacy of benvitimod was assessed at the end of the treatment period.
Of the patients receiving treatment with benvitimod cream, 50.4% achieved a psoriasis area and severity index (PASI) score of 75 at 12 weeks, which indicates a 75% or greater decrease in psoriasis size and severity compared to pre-treatment levels. In contrast, PASI 75 was achieved in only 38.5% and 13.9% of patients receiving calcipotriol ointment and placebo, respectively. Similarly, a significantly higher proportion of patients who received benvitimod cream (66.3%) achieved a static physicians' global assessment (sPGA) score of 0 or 1 (which indicate very low disease severity) compared to those who were put on placebo (33.5%).
This phase III trial also showed that the benvitimod cream was well tolerated. The most common side-effects were only mild irritation and itching at the site of application and these symptoms resolved spontaneously in most patients. No serious systemic side-effects were found.
Prof. Zhang remarks, "The results of this phase III trial are encouraging. The benvitimod cream can soon be a new treatment option for Chinese patients with plaque psoriasis. Given that most patients with psoriasis have plaque psoriasis, this will have a significant impact in terms of reducing the psoriasis disease burden in the country."
Perhaps, in time, it can become a standard method of psoriasis management all over the world.