Rheumatoid arthritis

Four main studies involving a total of 1,733 adults found Orencia effective in rheumatoid arthritis. The main measures of effectiveness were the reduction in symptoms of arthritis after treatment, as well as physical function (the ability to carry out everyday tasks) and the amount of damage to the joints (assessed using X‑rays).

The first two studies included 991 patients in whom methotrexate had not worked well enough. In the first study, symptoms of the disease were reduced in 61% (70 out of 115) of the patients adding the recommended dose of Orencia to methotrexate for 6 months, compared with 35% (42 out of 119) of the patients adding placebo (a dummy treatment). The second study found a similar effect of Orencia on symptoms of rheumatoid arthritis, as well as improved physical function and a reduced rate of joint damage after a year of treatment.

The third study included 391 patients in whom TNF blockers had not worked well enough. Adding Orencia to existing treatment led to a reduction in symptoms in 50% of the patients (129 out of 256) after 6 months, compared with 20% of the patients adding placebo (26 out of 133). Patients taking Orencia also had a greater improvement in physical function after six months.

In the fourth study, Orencia in combination with methotrexate was compared with Orencia alone and methotrexate alone in 351 adults who had not been treated with methotrexate (or with any biologic agents such as TNF alpha blockers), but may have been on other medicines for management of rheumatoid arthritis. Adding Orencia and methotrexate to existing treatment for 12 months reduced symptoms in 61% of the patients (70 out of 115), compared with 42% of the patients on Orencia alone (48 out of 113) and 45% of the patients on methotrexate alone (52 out of 115).

In addition, a study involving around 1,370 patients with rheumatoid arthritis found similar benefit for both Orencia given by injection under the skin and Orencia given by infusion.

Polyarticular juvenile idiopathic arthritis

In polyarticular juvenile idiopathic arthritis, Orencia infusion was found effective in one main study involving patients aged between 6 and 17 years whose previous treatment had not worked. The main measure of effectiveness was how long it was before the patient’s disease flared up again. All patients received Orencia for 4 months, after which the 122 whose condition had improved on Orencia were either switched to placebo or continued receiving Orencia. Around three-quarters of the patients were also taking methotrexate. Over 6 months, 20% of the patients receiving Orencia had a flare-up (12 out of 60), compared with 53% of those receiving placebo (33 out of 62).

A further study in 219 children with polyarticular juvenile idiopathic arthritis aged 2 to 17 years showed that Orencia given by injection under the skin produced expected levels of active substance in the blood based on data with Orencia given into a vein for other conditions. The study also led to similar improvements in symptoms to those seen with Orencia given into a vein in adults and children.

Psoriatic arthritis

Orencia was found effective in one main study involving 424 adult patients with psoriatic arthritis. The study included 259 patients who had previously been treated with a TNF alpha blocker. In around 60% of these patients the TNF alpha blocker had not worked well enough. The main measure of effectiveness was a reduction in symptoms of at least 20% after 24 weeks of treatment. Orencia given by injection under the skin reduced symptoms in 39% of the patients (84 out of 213) compared with 22% of the patients (47 out of 211) who received placebo.

In another study involving 170 patients with psoriatic arthritis, Orencia given by infusion at the recommended dose reduced symptoms by at least 20% after 24 weeks in over 47% of the patients (19 out of 40) compared with 19% of the patients (8 out of 42) who received placebo.