AN2 Therapeutics Clears Global Phase 2 Epetraborole Study

The Tip Desk · November 9, 2026 · 3 min read

Cash, cash equivalents and investments were $80.2 million as of September 30, 2026, and the company said it expects to start polycythemia vera enrollment by year-end.

AN2 Therapeutics, Inc. (ANTX), a clinical-stage biopharmaceutical company building small-molecule drugs from a boron chemistry platform, said its global Phase 2 study of oral epetraborole in polycythemia vera is cleared to proceed in all planned jurisdictions and that it expects to initiate enrollment by the end of 2026.

The Menlo Park, California company received U.S. FDA clearance of its investigational new drug application, along with regulatory clearances in Australia and India. Startup activities are underway for a study evaluating efficacy and safety of oral epetraborole in adults with phlebotomy-dependent PV. Enrollment is expected to begin with an open-label sentinel cohort receiving a predicted subtherapeutic dose to assess pharmacokinetics and safety. After that cohort, a safety monitoring committee is expected to advise on dose selection for Part 1, an open-label, single-arm, 28-week evaluation of epetraborole to maintain hematocrit control and reduce phlebotomy frequency. The company anticipates releasing Part 1 data periodically throughout 2027.

In the second quarter the company had held a pre-IND meeting with the FDA and planned an IND filing in the third quarter, with enrollment anticipated in the fourth quarter. The third-quarter update converted that plan into clearances across the U.S., Australia and India.

Enrollment is ongoing in an investigator-initiated Phase 2 trial of epetraborole in M. abscessus lung disease. The 84-patient, multicenter, randomized, double-blind, placebo-controlled study is being led by Dr. Kevin Winthrop at Oregon Health and Science University across an estimated 10 to 15 U.S. sites. The company anticipates reporting topline results in late 2027, subject to enrollment progress.

Startup activities are also underway for a Phase 2 proof-of-concept study of AN2-502998 in chronic Chagas disease. The company said AN2-504661 was selected as an oral development candidate for hypophosphatasia, with a Phase 1 planned for the second half of 2027. In September, the Gates Foundation awarded an extension of funding to support tuberculosis research under the company’s collaboration with GSK. Cameron Trenor, M.D., was appointed Chief Medical Officer in August.

Net loss for the third quarter of 2026 was $8.0 million, compared with $9.4 million a year earlier, or $0.17 a share versus $0.31 a share. Weighted-average shares used in computing net loss were 46.1 million, versus 30.3 million a year earlier.

Research and development expenses were $5.7 million, compared with $7.0 million in the year-ago quarter, which the company attributed to lower preclinical and research, other miscellaneous, and clinical trial expenses, partly offset by higher personnel-related and chemistry manufacturing and controls costs. General and administrative expenses were $2.9 million, compared with $3.0 million a year earlier, on lower personnel-related expenses partly offset by higher professional and outside services and other miscellaneous expenses. Interest income was $0.7 million, consistent with $0.7 million a year earlier. Total operating expenses were $8.67 million, versus $10.04 million a year earlier.

Cash, cash equivalents and investments were $80.2 million as of September 30, 2026. The company said it projects that existing cash, cash equivalents and investments will sustain operations into 2029 under the current operating plan. Cash and cash equivalents were $20.2 million, short-term investments $44.2 million, and long-term investments $15.8 million.

Co-Founder, Chairman, President and CEO Eric Easom said the quarter was marked by continued execution across the clinical pipeline and progress expanding opportunities from the boron platform, including FDA IND clearance for epetraborole in PV and the selection of AN2-504661 as a second development candidate this year.