Copyright © 2026 Authors retain the copyright of this article. This article is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

@article{201686,
        author = {Prince Kumar},
        title = {AVIAN INFLUENZA: A PHARMACEUTICAL PERSPECTIVE ON ANTIVIRAL CHEMISTRY},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {12},
        number = {12},
        pages = {7257-7270},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=201686},
        abstract = {Avian influenza viruses, particularly the highly pathogenic strains such as H5N1 and H7N9, represent a persistent threat to global health security due to their zoonotic potential and high mortality rates in humans. From a pharmaceutical perspective, the challenge lies in developing small-molecule inhibitors that can keep pace with the virus's rapid antigenic drift and shift. This review explores the medicinal chemistry of current antivirals and the emerging chemical scaffolds designed to bypass existing resistance mechanism. The primary focus of current antiviral chemistry remains the Neuraminidase (NA) enzyme. Neuraminidase inhibitors (NAIs), such as Oseltamivir and Zanamivir, were designed based on the transition-state analog of sialic acid. Chemically, these molecules mimic the oxocabenium ion intermediate, binding with high affinity to the conserved active site of the NA protein. However, the emergence of the H275Y mutation has significantly diminished the efficacy of Oseltamivir by altering the hydrophobic pocket of the enzyme. This necessitates the development of next-generation NAIs with modified side chains (e.g., C4-substituted derivatives) that maintain binding affinity even in mutated strains Beyond NAIs, the pharmaceutical landscape has shifted toward the Viral Polymerase Complex (PA, PB1, and PB2). The recent clinical success of Baloxavir Marboxil, a "cap-snatching" inhibitor, marks a milestone in antiviral chemistry. Baloxavir functions as a prodrug, which is metabolized into its active form to chelate the manganese ions (Mn^{2+}) within the PA subunit's active site. By disrupting the initiation of viral mRNA synthesis, polymerase inhibitors offer a broader window of therapeutic intervention compared to traditional therapies Furthermore these abstract highlights the revival of M2 Ion Channel blockers. While amino adamantanes like Amantadine have largely been abandoned due to widespread resistance, new chemical synthesis efforts are focusing on "dual-target" molecules and novel spiro-adamantane derivatives that can block the pore even in the presence of the S31N mutation. The future of avian influenza therapeutics lies in Structure-Based Drug Design (SBDG) and Host-Directed Antivirals. By targeting host cell factors required for viral replication rather than the virus itself pharmaceutical scientists hope to create a "resistance-proof" barrier. Additionally, the integration of PROTAC (Proteolysis Targeting Chimera) technology offers a revolutionary chemical approach to degrade viral proteins rather than just inhibiting them. In conclusion, while current antivirals provide a first line of defense, the chemical evolution of multi-target inhibitors and combination therapies is essential to mitigate the pandemic potential of avian influenza. To combat the inevitable rise of resistance, current research is pivoting toward Host-Directed Antivirals (HDAs). Instead of targeting the rapidly mutating virus, HDAs target host cell pathways (such as the Raf/MEK/ERK signaling pathway) that the virus hijacks for its lifecycle. Because host proteins do not mutate as quickly as viral proteins, this approach offers a higher "barrier to resistance." Additionally, the development of PROTACs (Proteolysis Targeting Chimeras) is gaining traction. These heterobifunctional molecules bring a viral protein into close proximity with an E3 ubiquitin ligase, marking the viral component for proteasomal degradation. This represents a paradigm shift from simple "inhibition" to active "destruction" of viral machinery.},
        keywords = {Avian Influenza (H5N1/H7N9), Medicinal Chemistry, Neuraminidase Inhibitors, Polymerase Complex, Drug Resistance, Structure-Activity Relationship (SAR)Introduction},
        month = {May},
        }