Operabamur

Operabamur is a synthetic phosphoramidate nucleoside analog developed by the pharmaceutical research group Quintum Biopharma for the treatment of chronic viral infections. The compound was first identified in a high‑throughput screening of nucleotide analogues in 2013 and entered preclinical testing by 2015. Operabamur’s chemical structure incorporates a 5‑fluoro substitution on the ribose moiety to enhance metabolic stability and a beta‑hydroxyl group that increases selectivity for viral RNA polymerase enzymes.

The drug’s mechanism of action involves competitive inhibition of the active site of viral RNA-dependent RNA polymerases. In vitro assays demonstrate potent inhibition of the replication of several negative‑sense RNA viruses, including influenza A (IC50 = 0.8 µM) and respiratory syncytial virus (IC50 = 1.1 µM). Animal studies in murine models of influenza respiratory infection showed a dose‑dependent reduction in viral titers and improved survival rates. The pharmacokinetic profile in rodents reveals a plasma half‑life of approximately 4.5 hours and extensive tissue distribution to the lungs and liver.

Phase I clinical trials assessed safety and tolerability of operabamur in healthy adults; the results, published in 2022, reported no grade 3 or higher adverse events at doses up to 200 mg orally twice daily. Phase II trials began in 2024 for hospitalized patients with severe influenza, focusing on endpoints of viral load reduction and clinical recovery.

Regulatory status is pending submission to the U.S. Food and Drug Administration and the European Medicines Agency. Expected timelines for Phase III trials depend on early outcomes of the 2025 studies. Current research also explores combination therapy with neuraminidase inhibitors and potential use in other viral diseases such as dengue and Zika virus infections.