Golimumab

• Rheumatoid Arthritis
• Psoriatic Arthritis
• Ankylosing Spondylitis
• Ulcerative Colitis

Golimumab is a fully human monoclonal antibody that targets tumor necrosis factor alpha (TNF-α), used in the treatment of several inflammatory autoimmune conditions. This biologic offers once-monthly subcutaneous or intravenous dosing for sustained TNF inhibition.

Mechanism of Action

Golimumab is a human IgG1κ monoclonal antibody that binds with high affinity and specificity to both soluble and transmembrane forms of human tumor necrosis factor alpha (TNF-α), neutralizing its biological activity. TNF-α is a pro-inflammatory cytokine that plays a central role in the pathogenesis of inflammatory diseases by activating immune cells, inducing other pro-inflammatory cytokines, promoting angiogenesis, and stimulating tissue degradation. By binding to TNF-α, golimumab prevents it from interacting with its cell surface receptors, thereby reducing inflammation, joint damage, and disease activity in autoimmune conditions.

Available Formulations

Golimumab is available for subcutaneous injection in prefilled syringes and autoinjectors (Simponi) containing 50 mg/0.5 mL or 100 mg/mL, and for intravenous infusion (Simponi Aria) as 50 mg/4 mL vials. The SC formulation can be self-administered after proper training. The medication requires refrigeration.

Medical Uses

Golimumab is FDA-approved for moderately to severely active rheumatoid arthritis (with methotrexate), active psoriatic arthritis (alone or with methotrexate), active ankylosing spondylitis, moderately to severely active ulcerative colitis (in patients with inadequate response to prior therapy or requiring continuous corticosteroids), and active polyarticular juvenile idiopathic arthritis (IV formulation, ages 2+). Clinical trials demonstrated significant improvements in signs and symptoms, physical function, and quality of life.

Dosing Guidelines

For rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis, the SC dose is 50 mg once monthly. For ulcerative colitis, the SC dose is 200 mg initially, 100 mg at week 2, then 100 mg every 4 weeks; patients under 80 kg with inadequate response may continue 100 mg, while those 80 kg or over may increase to 200 mg. For IV administration (RA), 2 mg/kg is given at weeks 0 and 4, then every 8 weeks. SC injections should be given in the thigh, lower abdomen, or upper arm.

Important Safety Information

Golimumab carries boxed warnings for serious infections (including tuberculosis, invasive fungal infections, bacterial/viral infections, and opportunistic infections) and malignancy (including lymphoma and other malignancies, some fatal, in children and adolescents). All patients should be tested for latent TB before starting therapy. Treatment should not be initiated during active infections. Other serious risks include hepatitis B reactivation, heart failure worsening, demyelinating disease, cytopenias, lupus-like syndrome, and serious allergic reactions.

Drug Interactions

Concurrent use with anakinra or abatacept is not recommended due to increased serious infection risk. Live vaccines should not be given concurrently. No formal drug interaction studies have been conducted. The formation of CYP450 enzymes may be altered by chronic inflammation; monitoring is recommended for narrow therapeutic index drugs when starting or stopping golimumab.

Where Golimumab Sits Among TNF Inhibitors

Golimumab is one of five TNF inhibitors, and for rheumatoid arthritis it is rarely the first biologic tried; adalimumab and etanercept have longer track records and biosimilar versions that most plans prefer. Golimumab is chosen when once-monthly injection matters more to a patient than cost, when a supervised infusion is preferred, or after loss of response to another TNF inhibitor, since a second agent in the class often works when the first stops. For ulcerative colitis, it competes with infliximab and adalimumab and with the newer classes, vedolizumab and ustekinumab; it is notably not approved for Crohn's disease, unlike infliximab and adalimumab. For psoriatic arthritis with significant skin disease, an IL-17 inhibitor such as secukinumab is often preferred because it clears skin better. The American College of Rheumatology publishes patient-level guidance on the class.

Screening, Expectations, and Monitoring

Before the first dose, latent tuberculosis and hepatitis B testing are done and vaccinations are brought up to date, because live vaccines are off the table once therapy starts. This applies to every TNF inhibitor and is not skipped for a flaring patient. In rheumatoid arthritis, golimumab is given with methotrexate, which improves the response and reduces anti-drug antibody formation; patients who stop methotrexate because they feel better frequently lose the benefit of the biologic months later.

Joint symptoms usually begin to improve within a few weeks, and a lack of any response by about three months is the usual trigger to switch. Monthly dosing is convenient but easy to forget; a dose more than a couple of weeks late is worth mentioning to the prescriber. Between doses, the main thing patients watch for is infection with muted signs: a low-grade fever, a cough, or a skin infection that does not resolve is reason to call rather than wait, and the drug is held during any serious infection or around surgery. Blood counts and liver enzymes are checked periodically, mostly because of concurrent methotrexate, and an annual skin examination is prudent in Florida given the class-wide increase in non-melanoma skin cancer. Our immunology and musculoskeletal teams coordinate the screening, and the MedlinePlus golimumab monograph lists the warning signs patients are told to report.

Special Populations

There are limited data on golimumab use during pregnancy. Animal studies showed no evidence of harm. Use during pregnancy only if clearly needed. It is unknown whether golimumab is excreted in human breast milk; caution is advised. Safety and efficacy of IV golimumab have been established in children 2 years and older with polyarticular juvenile idiopathic arthritis; SC golimumab is not approved for pediatric patients. Elderly patients may be at increased risk for infections. No dose adjustment is needed for renal or hepatic impairment based on available data.