Dazukibart

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.^[1] It is classified as a potent, selective, humanized IgG1 neutralizing monoclonal antibody that specifically targets interferon beta (IFN-β).^[2]

Dazukibart

Clinical data
Other names	PF-06823859,
Drug class	anti-INF-β neutralizing antibody
Identifiers
CAS Number	2639474-65-8
PubChem CID	472419808
UNII	K2Q0JXS9B4
KEGG	D12464
ChEMBL	ChEMBL4297808

Mechanism of action

Dazukibart functions by neutralizing interferon beta-1 (IFNB1), a type I interferon that plays a critical role in autoimmune inflammation.^[3] The drug targets the dysregulated type I interferon pathway that is characteristic of several autoimmune conditions, particularly dermatomyositis, where IFN-β rather than IFN-α has been identified as the predominant elevated interferon.^[4]

Administration and dosing

Dazukibart is administered through intravenous infusion, though subcutaneous formulations are also being investigated.^[3] The drug is currently being evaluated in ongoing clinical trials to determine optimal dosing regimens for different indications.

Clinical development

Phase I studies

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 β levels.^[5]

Phase II studies

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.^[1][4] 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.^[1][6]

Phase III studies

As of 2025, dazukibart has entered Phase 3 clinical trials for the treatment of myositis, indicating advancement toward potential regulatory approval.^[7][8]

Therapeutic indications

Dermatomyositis

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.^[9]

Other indications

Dazukibart is also being investigated for the treatment of systemic lupus erythematosus and polymyositis, conditions that also involve dysregulated type I interferon signaling.^[10]

Regulatory status

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.^[11]