Approval is for both intravenous and subcutaneous (SC) injection formulations.
Psoriatic arthritis is a condition that stems from psoriasis, an autoimmune disease in which the body’s immune system attacks the skin, resulting in scaly, red patches on the skin. In some psoriasis patients, the immune system attacks the joints as well, leading to inflammation and the condition known as psoriatic arthritis, or PsA. Symptoms of PsA are highly variable among patients, coming and going over time and affecting one or many joints of the body.
This is the third rheumatic disease indication for Orencia as it was previously approved for use in rheumatoid arthritis (RA) and moderate to severe polyarticular juvenile idiopathic arthritis and may be used alone or with methotrexate (MTX)
The approval was based on results from two comparative clinical trials in which Orencia was shown to reduce disease activity in both TNF-naive and previously TNF-exposed PsA patients. Overall the trials included 594 adult patients.
The ACR20 response at Week 24 favored ABA over placebo using IV ABA (47.5% versus 19.0% PBO) or SC ABA (39.4% versus 22.3%). Modest effects on skin scores (compared to other approved agents) were also seen.
The safety profile seen with PsA patients was as expected with no new safety signals. The approval comes with the warning that abatacept not be administered concomitantly with TNF antagonists, and is not recommended for use concomitantly with other biologics therapies.
Weight based dosing regimens (for both SC and IV forms) is the same as that suggested for RA. Those receiving the subcutaneous injection once weekly can do so without the need of an intravenous loading dose.