key: cord-0998975-s2dh7e8f authors: Swathi, K.; .Nikitha, B; Chandrakala, B.; Lakshmanadevi, K.; Malleswari, M. title: Repurposing antiviral drugs on recently emerged viral infections: A review article date: 2021-03-31 journal: Mater Today Proc DOI: 10.1016/j.matpr.2021.03.143 sha: 0f52f49f4afed42e3031bc3849124128042df1fc doc_id: 998975 cord_uid: s2dh7e8f Finer understandings of drugs, for newly emerged diseases are becoming difficult nowadays. The contemporary approach is Drug Repurposing. Drug repurposing implies the exploration of surviving drugs for new restorative motive. Apart from conventional drug approaches, it is a profitable, brisk and reliable approach. The equivalent therapies for newly emerging and remerging viral infections are strenuous spot these days. The drug repurposing has helped in treating many viral reprofiling infectious diseases like CoVID-19, MERS, SARS, Influenza, Swine flu, Hanta, Zika, Ebola, Marburg, Human Adeno virus infection etc. The present review looks at describing the drug repurposing approach in various viral infections. The world has abundant and diverse forms of viruses Table 5 . The viruses like particle per biome in association with humans are 2.80 Â 1022. With the outbreak of emerging and remerging viral infections research has been put forth to develop new drugs on new targets and mechanism. Center for Drug Evaluation and Research (CDER) of FDA's approved 48 novel drugs during period 2019. From past 10 years, 2010-2018, CDER has averaged about 37 novel drugs (www.fda.gov). Nevertheless, the WHO and governments faces global ultimatum of emerging and remerging viral infections. Some infections viral diseases, which lack determined treatment, are CoVID-19, MERS, SARS, Influenza, Swine flu, Hanta, Zika, Ebola, Marburg, Human Adeno virus infection. Drug repurposing is also known as Redirecting, Repurposing, Repositioning, Reprofiling, Retasking, Rescuing and Therapeutic switching. It means development of new therapeutic purpose from old drugs. On average, hit ratio in development of new drug molecule is 2.01%. Traditional approach take long time to develop a new drug molecule when compared to repurposing drug approach as explained in Fig 1 and Fig 2 . Therapeutic switching is the foremost, riskless and economical approach in treatment of recently emerging and remerging infections Table 5 . Nowadays repurposing of drugs is secured and reliable strategy in pharmaceutical sectors. Table 3 Influenza is a contagious respiratory viral infection caused due to influenza A (20 subtypes: H1-H20) and influenza B in humans which belongs to the family orthomyxoviridae. It has segmented negative RNA. It is pleomorphic and enveloped with helical capsid. Viral genome is composed of single negative stranded RNA and with eight nucleoprotein segments. Virus is composed of surface glycoproteins which includes neuraminidase (NA) and hemagglutin (HA), nucleoprotein (N), matrix protein (M) and nonstructural proteins (NS1 and NS2) The clinical features include fever, body ache, cough and runny nose. Influenza virus transmitted specifically through ciliated pseudo stratified columnar respiratory epithelial cells of respiratory tract [6] . Table 4 Swine flu infection is a respiratory disease caused by Influenza A (H1N1) belonging to the family Orthomyxovirus. Hantavirus infection is caused due to single stranded negative chain RNA virus belonging to the family Hantaviridae of order Bunyavirales which are transmitted by rodent animals (mice, mouse, rat etc.) through faeces, saliva (droplets and aerosols) and urine and infrequently through bites of infected animals. The major challenge nowadays is intervention treatment for hanta virus particularly HPS cases. ETAR, Favipiravir, Ribavirin (RBV), Lactoferrin, Vandetanib, Corticosteroids, Immunotherapy Monoclonal Antibodies (These are evaluated by passive transfer), Immunotherapy-Polyclonal Antibodies: Hantavirus DNA vaccine is currently in progress. Table 6 7. Ebola disease is known as Ebola haemorrhagic viral disease. It is caused due to the Ebola virus which belongs to the family filoviridae and order mononegavirales. Drugs: Chloroquine, Amodiaquine, Clomiphene and Toremiphine, Interferons, Amioderene, Sertraline and Bepridil, Favipiravir, Azithromycin. Marburg virus disease is known as Marburg haemorrhagic fever. It is closely related to the well-known Ebola virus (EBOV) it is caused by Marburg virus (MARV Table 6 Zika virus infection is an asymptomatic disease transmitted by mosquitoes. Antihistamines Pruritic rashes Fluids Prevent dehydration Drugs: There is no proper treatment for Marburg virus infection. The drugs which are used for treatment of Ebola viral infection are preferred for the recovery of the patient. Table 8 Human Adeno virus infection is caused by human adeno virus ((HAdV). Adeno viruses are group of viruses that cause variety of infections such as respiratory illness, conjunctivitis, croup, bronchiolitis and pneumonia. HAdV exists in seven known HAdV species The first line adenovirus drugs are: -Cidofovir, Ribavirin [6, 7, 8, 9] Middle east respiratory syndrome-coronavirus infection: An overview Viruses as winners in the Game of Life Epidemic keratoconjunctivitis due to the novel hexon-chimeric-intermediate 22,37/H8 human adenovirus Evidence for camel-to-human transmission of MERS coronavirus Viral pathogen with increasing importance Real-time qualitative PCR for 57 human adenovirus types from multiple specimen sources Tropism and replication of Middle East respiratory syndrome coronavirus from dromedary camels in the human respiratory tract: An in-vitro and ex-vivo study Synthesis of 1-beta -dribofuranosyl-3-ethynyl-[1,2,4]triazole and its in vitro and in vivo efficacy against hanta virus AbdolMohammadi et alZika Virus Infection, Basic and Clinical Aspects: A Review Article The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.