A last stage trial on a rheumatoid arthritis drug developed by Pfizer has shown significant results with reduced symptoms and impressive mobility. The new drug, tasocitinib was tried on 611 patients and met two of the three primary goals in its Phase III study.

Tasocitinib, a new class of oral drugs, known as JAK inhibitors, impacts the signaling of proteins involved in inflammatory and autoimmune diseases. I“This is the first oral medication for rheumatoid arthritis that has had a successful Phase III study this century," said Dr Roy Fleischmann, the study's primary investigator. "When it works, it really works”.

Fleischmann will present the results at the American College of Rheumatology meeting in Atlanta this week.
Tasocitinib is being touted as one of the most promising drugs from Pfizer and has already projected multibillion-dollar peak sales from analysts.

As many as 65.7 percent of patients who received 10 milligrams of tasocitinib twice a day achieved at least a 20 percent improvement after three months of treatment. Patients also reported improvement in physical functions, such as ability to fasten buttons.

Rheumatoid arthritis attacks healthy tissue, causing inflammation in and around the joints. It affects 1.3 million people in the United States and about 1 percent of adults worldwide, according to Pfizer.

It is treated with injected biotech drugs, such as Humira from Abbott Laboratories, which is expected to have sales in excess of $6 billion this year, or Amgen Inc's Enbrel which is set to touch a business target of more than $3.5 billion.

"The oral pill rather than an injection seems to work similar and is more convenient for patients,” said Fleischmann.
Serious adverse events were reported in 25 tasocitinib patients. Six cases of serious infection also reported over the six months of the study. "What we have not seen so far is the tuberculosis, or the opportunistic infections that we've seen with the biologics," Fleischmann said.

More than half of patients on tasocitinib over the first three months of the trial reported decreases in white blood cells and increases in bad LDL cholesterol. There was also an increase seen in good HDL cholesterol as well as an increase in red blood cell count and in liver enzymes in some patients.

"It has a safety profile that is very reasonable because the benefit is so good and the risk relatively small," Fleischmann said.