Pfizer (NYSE:PFE) released Thursday strong results from a clinical trial of its investigational treatment for patients with chronic plaque psoriasis.

Affecting 125 million people worldwide, Psoriasis is a chronic autoimmue skin disease characterized by raised, inflamed, red lesions that can be itchy and painful. Holding 80% of total cases, plaque psoriasis is the most common form of the disease.

The phase II study of tasocitinib, an oral Janus Kinase [JAK] inhibitor, showed a “statically significant” increase in the number of patients that achieved at least a 75% reduction from baseline Psoriasis Area and Severity Index [PASI] at week 12 in patients with chronic moderate to severe plaque psoriasis

JAK pathways are believed to play an important role in the psoriasis disease cascade and researchers are conducting clinical trials to test whether inhibiting the pathways can reduce psoriasis symptoms. 

“Plaque psoriasis affects millions of people globally and can have a negative impact on a person's quality of life,” said Saeed Fatenejad, M.D., vice president of clinical development & medical affairs and disease area lead for inflammation of the Pfizer specialty care business unit. 

As early as week four in the study, twice daily treatments of the drug “significantly improved” patient’s quality of life related to health issues.

Of the 197 study participants, three patients experienced a total of five serious adverse effects during the study.

Pfizer has initiated its study of tasocitinib in people with chronic moderate to  severe plaque psoriasis in a phase 3 program called the Oral Psoriasis Treatment [OPT] to further study the drug's efficacy and safety.

“We are encouraged by the results seen in the Phase 2 study and look forward to further studying tasocitinib in the recently initiated Phase 3 program called the OPT trials,” Fatenejad said.

The drug is also being studied for the potential treatment of rheumatoid arthritis in a group of studies called the ORAL trials, as well as in dry eye, Crohn's disease, ulcerative colitis and solid organ transplant.