June 5 (Reuters) - Patients taking Johnson & Johnson's Stelara experienced significant relief from the painful symptoms of active psoriatic arthritis, according to results of a late-stage study.
The drug met the main goal of the 615-patient Phase III clinical trial -- at least a 20 percent improvement in signs and symptoms of the disease after 24 weeks -- at both tested doses compared with a placebo, the data showed.
Fifty percent of patients who received 90 milligrams of Stelara and 42 percent who got the 45 mg dose achieved the goal known as ACR 20. That compared with 23 percent of patients in the placebo group who reached ACR 20.
The results, which were being presented on Friday at the European League Against Rheumatism (EULAR) meeting in Berlin, were deemed to be statistically significant, researchers said.
"Psoriatic arthritis is something of a calamity for patients who are afflicted," Professor Iain McInnes, the study's lead investigator from the University of Glasgow, said in a telephone interview from Berlin. "It's associated with pain, with stiffness, with loss of function and with high levels of anxiety and psychological stress. There's a lot of unmet need out there."
Stelara, a biotech drug known chemically as ustekinumab, is already approved to treat the skin condition plaque psoriasis. The new data -- the first of two planned Phase III studies -- will be used by J&J to seek expanded approval to treat psoriatic arthritis, a chronic inflammatory condition that causes pain and swelling of the joints and around the tendons.
Stelara patients in the study also experienced significant improvements in physical function as measured by the Health Assessment Questionnaire Disability Index. Pain and inflammation of sites where tendons and ligaments attach to the bone, known as enthesitis, and of the fingers or toes, called dactylitis, were reduced.
The higher dose of Stelara showed statistically significant improvements in the more difficult to achieve measurements ACR 50 and ACR 70.
For those who received the 90 mg dose of Stelara, 28 percent of patients achieved ACR 50 and 14.2 percent achieved ACR 70, compared with ACR 50 of 8.7 percent and ACR 70 of 2.4 percent for placebo.
Stelara works by blocking interleukin proteins associated with inflammation. Drugs such as J&J's Remicade and Abbott Laboratories' Humira, which have been a mainstay of rheumatoid arthritis treatment and have had success against psoriatic arthritis, block a protein called tumor necrosis factor, or TNF. However, those and older drugs do not work for some patients and can eventually stop helping others after a period of time, McInnes said.
He called the Stelara data exciting. "Any new pathway that offers the opportunity to improve the quality of life and the clinical disease in our patients is to be welcomed," he said.
Patients in the study had active psoriatic arthritis, including at least five tender and five swollen joints, despite prior treatment with a disease-modifying antirheumatic drug such as methotrexate and/or common anti-inflammatory pain drugs such as ibuprofen. They had not been treated with anti-TNF drugs.
Study subjects received injections of either 45 mg or 90 mg of Stelara or a placebo at the start, at week four and then every 12 weeks. The results to be presented on Friday were taken from week 24 of the trial. The study plans to continue to treat and follow these patients for up to two years, J&J said.
Psoriatic arthritis afflicts up to 30 percent of people with psoriasis, according to the National Psoriasis Foundation. It estimates about 7.5 million people in the United States and about 125 million worldwide suffer from psoriasis.
Serious side effects were reported in two percent of Stelara-treated patients in the study, which was about the same as in the placebo group.
While the J&J drug can decrease the ability to fight infections or cancer, no malignancies, tuberculosis, serious infections, opportunistic infections, major heart problems or deaths occurred through the placebo-controlled portion, or week 16, of the study, researchers said.
One stroke occurred in the Stelara 45 mg group after the placebo-controlled period in a patient with a history of prior stroke and other risk factors, the company said. (Editing by Prudence Crowther)