Opna Bio

Opna Bio is a clinical-stage biopharmaceutical company focused on the discovery and development of novel oncology therapeutics. Based in South San Francisco, California, the company designs small-molecule drugs that target key regulators of cancer, with an emphasis on epigenetic modulators engineered for better safety and tolerability. Its lead clinical compounds are zavabresib (OPN-2853), a bromodomain and extra-terminal motif (BET) inhibitor being evaluated in patients with myelofibrosis in combination with ruxolitinib, and OPN-6602, an oral small-molecule inhibitor of the E1A binding protein (EP300) and CREB-binding protein (CBP), currently in a Phase 1 clinical trial in multiple myeloma patients. Opna Bio's scientific approach centers on "efficacy and safety by design." The company rationally designs epigenetic modulators intended to overcome safety and tolerability issues associated with small-molecule inhibitors of this class. Both OPN-6602 and zavabresib have a unique pharmacokinetic profile that enables "pulsatile dosing": the compounds were synthesized to have a short half-life and high C-max, enabling daily dosing and prolonged pharmacodynamic response. Beyond these two clinical assets, Opna Bio has a research program aimed at disrupting the actions of fragile-X multifunctional RNA-binding protein (FMRP), an unprecedented new cancer target. The role of FMRP in cancer was elucidated in the laboratory of Dr. Douglas Hanahan, co-founder of Opna Bio and co-author of the seminal "Hallmarks of Cancer" series. The company's pipeline spans myelofibrosis, multiple myeloma, myeloma and lymphoma, and solid tumors. Its BET inhibitor zavabresib is being developed for myelofibrosis; its EP300 inhibitor OPN-6602 is in clinical development for multiple myeloma; multi-functional degraders are being explored for myeloma and lymphoma; and an FMRP inhibitor program (OPN-FMRP) targets solid tumors. Opna Bio states that it is currently validating its approach of competitive safety and efficacy through differentiated pharmacokinetics with its epigenetic inhibitors, both of which are in early-stage clinical development in patients with hematologic malignancies. Opna Bio has received regulatory designations for its programs. In January 2026, the company announced that OPN-2853 (zavabresib) received Orphan Drug Designation for the treatment of myelofibrosis. In April 2026, Opna Bio announced that OPN-6602 received Fast Track Designation for the treatment of multiple myeloma, with the compound then treating patients in a Phase 1 clinical trial. In December 2025, the company showcased multi-functional degraders with potent anti-myeloma activity and encouraging spleen reductions in patients with myelofibrosis treated with OPN-2853 and ruxolitinib at the 67th Annual Meeting of the American Society of Hematology (ASH). The Opna team describes a proven track record of scientific expertise and commercial value creation, having advanced multiple FDA-approved drugs to market. The company is privately held and operates primarily in the United States.

Opna Bio is a clinical-stage biopharmaceutical company focused on the discovery and development of novel oncology therapeutics. The company is based in South San Francisco, California, and is privately held. Its scientific foundation is closely tied to the work of Dr. Douglas Hanahan, a co-founder of Opna Bio and co-author of the seminal "Hallmarks of Cancer" series, which proposed a set of traits commonly acquired by human cancer cells and crucial for the formation of malignant tumors. The role of fragile-X multifunctional RNA-binding protein (FMRP) in cancer was elucidated in Dr. Hanahan's laboratory, forming the basis of one of Opna Bio's research programs. Opna Bio describes its team as having a proven track record of scientific expertise and commercial value creation, having advanced multiple FDA-approved drugs to market. The company's strategy centers on rationally designed epigenetic modulators intended to overcome safety and tolerability issues associated with small-molecule inhibitors of this class. Its two lead clinical compounds, zavabresib (OPN-2853) and OPN-6602, were synthesized to have a short half-life and high C-max, enabling "pulsatile dosing" with daily administration and prolonged pharmacodynamic response. Zavabresib is a bromodomain and extra-terminal motif (BET) inhibitor being evaluated in patients with myelofibrosis in combination with ruxolitinib. OPN-6602 is an oral, small-molecule inhibitor of the E1A binding protein (EP300) and CREB-binding protein (CBP), currently in a Phase 1 clinical trial in multiple myeloma patients. The company also has a research program aimed at disrupting the actions of FMRP, an unprecedented new cancer target, and is exploring multi-functional degraders for myeloma and lymphoma. In December 2025, Opna Bio showcased multi-functional degraders with potent anti-myeloma activity and encouraging spleen reductions in patients with myelofibrosis treated with OPN-2853 and ruxolitinib at the 67th Annual Meeting of the American Society of Hematology (ASH). In January 2026, the company announced that OPN-2853 (zavabresib) received Orphan Drug Designation for the treatment of myelofibrosis. In April 2026, Opna Bio announced that OPN-6602 received Fast Track Designation for the treatment of multiple myeloma, with the compound then treating patients in a Phase 1 clinical trial. The company states that it is currently validating its approach of competitive safety and efficacy through differentiated pharmacokinetics with its epigenetic inhibitors, both of which are in early-stage clinical development in patients with hematologic malignancies.

• Opna Bio showcased multi-functional degraders with potent anti-myeloma activity and encouraging spleen reductions in patients with myelofibrosis treated with OPN-2853 and ruxolitinib at the 67th Annual Meeting of the American Society of Hematology (ASH).

• Opna Bio announced that OPN-2853 (zavabresib) received Orphan Drug Designation for the treatment of myelofibrosis.

• Opna Bio announced that OPN-6602 received Fast Track Designation for the treatment of multiple myeloma; OPN-6602 was then treating patients in a Phase 1 clinical trial.

Clinical-stage oncology company designing differentiated epigenetic inhibitors and degraders with improved safety and tolerability through pulsatile dosing.

• Zavabresib (OPN-2853)

  A differentiated bromodomain and extra-terminal motif (BET) inhibitor being developed for the treatment of myelofibrosis, evaluated in combination with ruxolitinib.

• OPN-6602

  A best-in-class oral, small-molecule inhibitor of the E1A binding protein (EP300) and CREB-binding protein (CBP), currently in a Phase 1 clinical trial in multiple myeloma patients.

• Multi-functional degraders

  Research-stage multi-functional degraders being explored for myeloma and lymphoma.

• OPN-FMRP

  An FMRP inhibitor research program targeting solid tumors, based on the role of fragile-X multifunctional RNA-binding protein (FMRP) in cancer elucidated in Dr. Douglas Hanahan's laboratory.

1. 1Opna Bio - Oncology pharmaceutical companyopnabio.com
2. 2About - Opna Bioopnabio.com
3. 3Opna Bio (United States) - Wikidatawikidata.org