IV golimumab works in kids with polyarticular-course juvenile idiopathic arthritis

Body surface area-based dosing of intravenous (IV) golimumab appears safe and provides pharmacokinetic (PK) exposure in paediatric patients with active polyarticular-course juvenile idiopathic arthritis (pc-JIA) similar to that found in adults with rheumatoid arthritis (RA), according to the results of an open-label study.

In total, 127 children (median age, 13 years; 73 percent female; median weight, 42.4 kg) with active pc-JIA despite methotrexate therapy for ≥2 months received 80 mg/m² golimumab at weeks 0, 4, then every 8 weeks through week 52 plus methotrexate weekly through week 28.

Pc-JIA was classified as rheumatoid factor (RF)-negative in 43 percent of patients and RF-positive in 35 percent. The most common medications used previously were nonsteroidal anti-inflammatory drugs (NSAIDs; 94 percent) and systemic glucocorticoids (57 percent); there were 28 patients (22 percent) who had received prior biologic therapy.

At week 28, JIA American College of Rheumatology (ACR) 30, 50, 70, and 90 response rates occurred in 84 percent, 80 percent, 70 percent, and 47 percent of the patients, respectively. Responses were maintained through week 52.

Golimumab serum concentration at week 28 was 399 µg·day/ml, while model-predicted steady-state area under the curve (AUCss) over an 8-week dosing interval was 0.40 µg/ml. Both were consistent across age categories and comparable to IV golimumab dosed 2 mg/kg in adults with RA. PK exposure was maintained at week 52.

A highly sensitive drug-tolerant assay facilitated detection of golimumab antibodies and neutralizing antibodies in 31 percent and 19 percent of patients, respectively. Median trough golimumab concentration was lower in antibody-positive than in antibody-negative patients.

Six patients developed serious infections, with one passing away due to septic shock.