July 14, 2020
The U.S. FDA has approved a new indication for Tremfya® (guselkumab), manufactured by Janssen Pharmaceuticals. The drug is now indicated to treat active psoriatic arthritis (PsA) in adults. It is the first interleukin (IL)-23 inhibitor to receive FDA approval for active PsA.
An estimated 1.5 million people in the United States suffer from psoriatic arthritis, a painful autoimmune condition that affects the skin and joints. Over time, the condition leads to permanent joint damage. Active PsA is defined as PsA with symptoms that cause unacceptable difficulties, such as swollen and tender joints, skin lesions, and pain in the spine, hips, and shoulders. Treatments are aimed at easing symptoms and slowing disease progression. Tremfya works by blocking IL-23, which is a type of cytokine, a substance produced by the body that provokes an inflammatory immune response.
In clinical studies, up to 64% of patients treated with Tremfya achieved an ACR20 response, versus up to 33% of patients treated with placebo. ACR20 is a system used in clinical studies to establish whether a patient with PsA improves on treatment. Achieving an ACR20 response requires the patient to have at least a 20% improvement in the number of tender and swollen joints, as well as a 20% improvement in three out of five additional criteria used to measure PsA severity.
Recommended dosing under the new indication is 100mg administered via subcutaneous injection at Week 0, Week 4, and every eight weeks thereafter. Tremfya can be used alone or in combination with conventional disease-modifying antirheumatic drugs (DMARDs) such as methotrexate.
Originally FDA approved in 2017, Tremfya is also indicated to treat moderate-to-severe plaque psoriasis in adults who are candidates for systemic therapy or phototherapy.