Dazukibart (previously known as PF-06823859) is a humanized monoclonal antibody developed by Pfizer for the treatment of autoimmune diseases, particularly dermatomyositis and systemic lupus erythematosus. It is classified as a potent, selective, humanized IgG1 neutralizing monoclonal antibody that specifically targets interferon beta (IFN-ò).
Dazukibart functions by neutralizing interferon beta-1 (IFNB1), a type I interferon that plays a critical role in autoimmune inflammation. The drug targets the dysregulated type I interferon pathway that is characteristic of several autoimmune conditions, particularly dermatomyositis, where IFN-ò rather than IFN-ñ has been identified as the predominant elevated interferon.
Dazukibart is administered through intravenous infusion, though subcutaneous formulations are also being investigated. The drug is currently being evaluated in ongoing clinical trials to determine optimal dosing regimens for different indications.
Initial safety and pharmacokinetic studies of dazukibart (then known as PF-06823859) were published in 2020, demonstrating an acceptable safety and tolerability profile in healthy volunteers. These studies supported its continued development for disorders associated with increased interferon ò levels.
A landmark phase 2 clinical trial published in The Lancet in January 2025 demonstrated significant efficacy of dazukibart in treating adults with moderate-to-severe dermatomyositis. The multicentre, double-blind, randomized, placebo-controlled study was conducted across 25 sites in Europe and the USA. The study showed that both 150 mg and 600 mg IV doses every 4 weeks met the primary endpoint of significantly decreasing CDASI-A scores at 12 weeks compared with placebo, with dazukibart resulting in a pronounced reduction in disease activity and being generally well tolerated.
As of 2025, dazukibart has entered Phase 3 clinical trials for the treatment of myositis, indicating advancement toward potential regulatory approval.
The primary indication for dazukibart is dermatomyositis, a chronic autoimmune disease characterized by distinctive cutaneous eruptions, muscle weakness, and systemic manifestations including interstitial lung disease. Clinical studies have shown rapid onset of response in adult patients with moderate-to-severe refractory dermatomyositis.
Dazukibart is also being investigated for the treatment of systemic lupus erythematosus and polymyositis, conditions that also involve dysregulated type I interferon signaling.
Dazukibart has received orphan drug designation from the European Medicines Agency (EMA) for the treatment of dermatomyositis (designation EU/3/20/2392), recognizing the significant medical need for effective treatments for this rare autoimmune condition.