AMB-053 for IPF

Disease and Prevalence

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive inflammatory and fibrotic interstitial lung disease of unknown (idiopathic) cause which carries a sobering 5-year survival prognosis of approximately 20% (1). Indeed, an estimated 50,000 people die from IPF in the U.S. each year, more deaths than from breast cancer. Common risk factors for IPF include:

  • Cigarette smoking: Approximately 75% of people with IPF are current or previous cigarette smokers.

  • Male gender: Approximately 75% of patients with IPF are male.

  • Age: Most patients with IPF are over the age of 50 years.

In IPF, the lung tissue becomes scarred and the thickened stiff tissue leads to shortness of breath and a dry cough. Additional symptoms include fatigue, weight loss, aching muscles and joints and swelling of fingers and legs and toes. There’s no cure for IPF, but treatments can slow the lung damage and some patients receive lung transplants.

Incidence in the U.S. is estimated at 20,000-50,000 (2,3) with prevalence of ~100,000 (4).

Pathogenesis and AMB-053 Mechanism of Action

The etiology of IPF is not fully understood, but a current paradigm is that acute lung injury and early inflammatory responses, including macrophage activation, followed by persistent injury, leads to aberrant macrophage differentiation, wound healing responses, and pulmonary fibrosis (5). Certain types of macrophages, sometimes referred to a M2 macrophages, are thought to play a key role in the excessive fibrogenesis and development of IPF. Importantly, CSF-1 acting at the CSF-1R appears to play an important role in this pro-fibrotic macrophage response in IPF (6).

Figure 1. A schematic for the role of CSF-1 & M2 Macrophages in IPF

Key preclinical and clinical data supporting the utility of AMB-053 in IPF include:

  • CSF-1 -/- mice are protected from bleomycin-induced pulmonary fibrosis (7).

  • A neutralizing antibody to the mouse CSF-1R was shown to be anti-fibrotic in a model of radiation-induced PF which is considered by some to be the best animal model of human IPF (8).

  • A small molecule CSF-1R kinase inhibitor treatment paradigm prevented lung fibrosis in a mouse model of bleomycin-induced PF (9).

  • CSF-1 levels are increased and M2 macrophages are expanded in lung lavage samples of IPF patients and magnitudes correlate with disease diagnosis and severity (7,8).

Current Treatment & Unmet Need

Two drugs, pirfenidone and nintedanib, are approved by the European Medicines Agency and the US Food and Drug Administration for the treatment of IPF. However, both provide limited efficacy and are associated with an unfavorable side effect profile and quality of life endpoints are not significantly improved (10). The unmet need is clear: Drugs, or drug combinations, with improved efficacy and tolerability.

AMB-053 Differentiation

With a preclinically-validated mechanism of action and demonstrated clinical safety, tolerability, and activity (11), AMB-053 represents a First-In-Class therapeutic.


  1. Raghu G et al., Am. J. Respir. Crit. Care Med. 2011; 183:788

  2. Olson AL et al., Eur. Respir. Rev. 2018; 27:180077

  3. Kim DS et al., Proc. Am. Thorac. Soc. 2006; 3:285

  4. Ley B, Clin. Epidemiology 2013; 5:483-92

  5. Zhang L et al., Resp. Research 2018; 19:170

  6. Hou J et al., Cell Communication Signal 2018; 16:89

  7. Baran CP et al., Am. J. Respir. Crit. Care Med. 2007; 176:78,

  8. Meziani L et al., Eur. Respir. J. 2018; 51:1702120

  9. Zhao J et al., PLOS ONE 2018; 13:e0197604

  10. Maher T et al., BMC Pulmonary Med. 2017; 17:124

  11. Papadopoulos KP et al., Clin. Cancer Res. 2017; 23:5703

AMB-053 is the human monoclonal antibody which specifically binds and inhibits the CSF-1R. CSF-1 action at CSF-1R-bearing cells is thought to play a critical role in Idiopathic Pulmonary Fibrosis (IPF) pathogenesis.

Delivered via a proprietary technology, AMB-053 is mechanistically and clinically well-positioned as a First-In-Class therapeutic, with potentially minimal side effects, for the treatment of IPF.


Treating Orphan Diseases With Few or No Options.


Redwood City, CA, USA


Taipei, Taiwan