Pipeline

Our development pipeline spans hematologic diseases, infectious diseases, and oncology, alongside advanced research programs focused on targets in oncology, bone disorders and infectious diseases. We are committed to delivering high-impact drugs to patients that address critical medical needs and improve health outcomes. 

development pipeline graphic

Epetraborole – Polycythemia Vera

In March 2026, we announced our plan to expand the development of oral epetraborole into a Phase 2 proof-of-concept clinical study in adults with phlebotomy-dependent polycythemia vera (PV). PV is a slowly progressing blood cancer characterized by overproduction of red blood cells in the bone marrow. This overproduction increases hematocrit, which can lead to serious medical complications including arterial and venous thromboembolic events. If untreated, PV can be life-threatening. Despite available therapies, such as burdensome periodic therapeutic phlebotomies, many patients experience uncontrolled hematocrit levels and persistent symptoms, requiring long-term management to maintain adequate disease control. PV is estimated to affect approximately 155,000 people in the U.S.

Epetraborole – Mycobacterium abscessus complex lung disease 

Building on the microbiological and safety data from our prior non-tuberculous mycobacterial (NTM) study in treatment-refractory MAC, we believe that epetraborole has the potential to address a critical unmet need in M. abscessus lung disease, one of the most difficult to-treat NTM infections for which no FDA-approved therapy exists. M. abscessus lung disease is a serious NTM infection requiring prolonged therapy, initially often with IV-only antibiotics. People affected by this illness face limited, burdensome treatment options and high rates of morbidity and mortality. NTM lung disease represents a growing global health concern. It is estimated that approximately 120,000–150,000 people in the U.S. are living with NTM lung disease, of whom 10–15% are caused by M. abscessus.

AN2-502998 – Chagas Disease

We are studying AN2-502998 (formerly known as AN15368), an oral, boron-based small molecule CPSF3 inhibitor for the treatment of chronic Chagas disease, also known as American trypanosomiasis. Chagas disease is caused by the parasite Trypanosoma Cruzi (T. cruzi). Over 300,000 people are estimated to be infected in the U.S., 200,000 across Europe and Japan, and about 10 million worldwide. Left untreated, chronic T. cruzi infection is lifelong and can be life threatening. The parasite T. cruzi silently damages the heart and digestive system, with ~20-30% of people developing serious cardiac damage resulting in heart failure, stroke, or sudden death. There are no FDA approved treatments for adults with Chagas disease.

Our Boron-Chemistry Research and Development Initiatives

We are prioritizing targets in oncology and bone disorders where we believe boron chemistry may offer a competitive advantage in terms of binding-site differentiation, pharmacodynamics, drug-like properties and IP, including initially ENPP1 and PI3Kα. The unique binding modes of boron-containing compounds enable the discovery of inhibitors with high ligand efficiency against targets considered undruggable or difficult to access with traditional chemistry approaches. Boron chemistry has produced first-in-class molecules against a number of targets including CPSF3 (AN2-502998 and acoziborole) and LeuRS (epetraborole, ganfeborole and tavaborole). The Company has discovered preclinical compounds that demonstrate sub-nanomolar activity, high selectivity and excellent oral pharmacokinetic properties.

Melioidosis

We are also studying epetraborole for the treatment of acute melioidosis, a highly lethal bacterial infection and recognized biothreat. We completed enrollment in a 200-patient observational trial (non-epetraborole treatment) in October 2024 and in June 2025 announced key insights from the trial, which reinforce the high mortality of the disease, despite standard of care. This study provided critical data which will allow the Company to optimize the design of upcoming clinical studies. Discussions are underway with the U.S. government to fund Phase 2 development of epetraborole in acute melioidosis. Melioidosis has a 90-day mortality rate approaching 40%, despite standard of care drugs, including ceftazidime or meropenem. The aim of the program is to meaningfully lower the expected mortality rate by dosing epetraborole on top of SOC. If approved for the treatment of melioidosis, we plan to seek a priority review voucher and could generate revenue from U.S. and other governmental stockpiling, as well as from the use of treatment in disease-endemic countries.

Clinical Trials

AN2 Therapeutics is committed to delivering high-impact drugs to patients that address critical unmet needs and improve health outcomes. Successful clinical trials are required to gain regulatory approval for new medications to advance patient care and may be required to support any approved products.

For information on AN2 Therapeutics clinical trials that may be recruiting, search AN2 Therapeutics at www.clinicaltrials.gov

Presentations and Publications

Epetraborole, a Potential Oral Agent for Mycobacterium abscessus Lung Disease
NTM Conference 2025

Qualitative Interviews to Develop the MACrO2 Patient-Reported Outcome Measure in Treatment-Refractory MAC Lung Disease (TR-MAC-LD)
NTM Conference 2025

Validation of the Quality of Life-Bronchiectasis (QOL-B) Respiratory Domain Patient- Reported Outcome (PRO) Measure in Treatment-Refractory MAC Lung Disease (TR-MAC-LD)
NTM Conference 2025

Validation of the MACrO2 Patient-Reported Outcome (PRO) Measure in Treatment-Refractory MAC Lung Disease (TR-MAC-LD)
NTM Conference 2025

Results: Phase 2 Study (EBO-301) to Assess the Efficacy, Safety, and PK of Oral Epetraborole (EBO) in Patients with Treatment-refractory Mycobacterium avium Complex Lung Disease (TR-MAC-LD)
NTM Conference 2025

Design: Phase 2/3, Randomized, Double-Blind, Placebo-Controlled, Multicenter, Prospective EBO-301 Study to Assess the Efficacy, Safety, and PK of Oral Epetraborole (EBO) Versus Placebo (PBO), Each in Combination with an Optimized Background Regimen (OBR), in Patients with Treatment-Refractory Mycobacterium avium Complex Lung Disease (TR-MAC-LD)
NTM Conference 2025

In vitro susceptibility of 147 international clinical Mycobacterium abscessus isolates to epetraborole and comparators by broth microdilution
Journal of Antimicrobial Chemotherapy 2024

In vitro activity and minimum inhibitory concentration (MIC) of Epetraborole against Burkholderia pseudomallei
10th Annual World Melioidosis Congress 2024

Efficacy of epetraborole against Mycobacteroides abscessus in a mouse model of lung infection
Antimicrobial Agents and Chemotherapy 2024

In Vitro Evaluation of Drug–Drug Interaction Potential of Epetraborole, a Novel Bacterial Leucyl-tRNA Synthetase Inhibitor Pharmaceuticals 2024

Epetraborole, a leucyl-tRNA synthetase inhibitor, demonstrates murine efficacy, enhancing the in vivo activity of ceftazidime against Burkholderia pseudomallei, the causative agent of melioidosis
PLOS 2023

Epetraborole In Vitro Activity Against Mycobacterium Avium Complex Recent Clinical Isolates from Japan (#2135)
ID Week 2023

A Phase 1, Multicenter, Open-Label, Parallel-Group Study to Assess the Safety and Pharmacokinetics of Oral Epetraborole Tablets in Adult Subjects with Varying Degrees of Renal Function (#2144)
ID Week 2023

A Phase 1, Open-Label, Single Dose Study to Evaluate the Pharmacokinetics (PK), Safety, and Tolerability of Epetraborole Tablets and the Impact of Alcohol Dehydrogenase Genotype on the PK of Epetraborole and Metabolite M3 in Healthy Japanese Adult Subjects (#2556)
ID Week 2023

Epetraborole: A Novel Antibiotic for NTM Lung Disease & Melioidosis
ID Week 2023

Epetraborole: A Novel, Oral Antibiotic for NTM Lung Disease
ID Week 2022

Pharmacokinetic-Pharmacodynamic Target Attainment Analyses to Support Epetraborole Dose Selection for the Treatment of Patients with Mycobacterium avium Complex Lung Disease
ID Week 2022

Population Pharmacokinetic Model Development for Epetraborole and MAC Lung Disease Patients Using Data from Phase 1 and 2 Studies
ID Week 2022

Dose-response Studies of the Novel Bacterial Leucyl-tRNA Synthetase Inhibitor, Epetraborole, in the Intracellular Hollow Fiber System Model of Mycobacterium avium complex Lung Disease
ID Week 2022

Pharmacokinetics/pharmacodynamics of Epetraborole, a Novel Bacterial Leucyl-tRNA Synthetase Inhibitor, and High Intracellular Penetration in the Intracellular Hollow Fiber System Model of Mycobacterium avium Complex Lung Disease
ID Week 2022

Epetraborole, a Novel Bacterial Leucyl-tRNA Synthetase Inhibitor, Demonstrates Potent Efficacy and Improves Efficacy of Standard of Care Regimen Against Mycobacterium avium complex in a Chronic Mouse Lung Infection Model
ID Week 2022

In Vitro Activity of Epetraborole, a Novel Bacterial Leucyl-tRNA Synthetase Inhibitor, in Drug Combinations Against Nontuberculous Mycobacteria Including Resistance Frequency and MIC Characterization of Mycobacterium avium ATCC 700898 Epetraborole-resistant Mutants
ID Week 2022

In Vitro Activities of Epetraborole, a Novel Bacterial Leucyl-tRNA Synthetase Inhibitor, Against Mycobacterium avium Complex Isolates
ID Week 2022

In Vitro Drug-Drug Interaction Evaluation of Epetraborole, a Novel Bacterial Leucyl-tRNA Synthetase Inhibitor
ID Week 2022

Tolerability and Pharmacokinetics of Oral Epetraborole at the Predicted Therapeutic Dosage for Mycobacterium avium Complex (MAC) Lung Disease: A Phase 1b Dose-ranging and Food Effect Study
ID Week 2022