WO2022058323A1

WO2022058323A1 - Compounds for the treatment of viral infections

Info

Publication number: WO2022058323A1
Application number: PCT/EP2021/075269
Authority: WO
Inventors: Ulrich Betz
Original assignee: Merck Patent Gmbh
Priority date: 2020-09-18
Filing date: 2021-09-15
Publication date: 2022-03-24

Abstract

The present invention encompasses an DNA-PK inhibitor for use in the treatment of coronavirus infections, including COVID-19, alone or in combination with one or more additional therapeutic agents.

Description

COMPOUNDS FOR THE TREATMENT OF VIRAL INFECTIONS

TECHNICAL FIELD OF THE INVENTION

[0001] The present invention provides for the use of inhibitors of DNA-dependent protein kinase (DNA-PK) in the treatment of coronavirus infections, including SARS-CoV infections such as COVID-19.

BACKGROUND OF THE INVENTION

DNA-PK Inhibitors

To ensure the accurate maintenance and transfer of genetic information to progeny, mammalian cells have evolved sophisticated mechanisms to sense DNA damage, coordinate its repair, and prevent potential cancerogenic effects; this is collectively known as the DNA damage response (DDR). Diverse types of lesions can be generated in DNA, ranging from minor base modifications to strand breaks, leading to large deletions or genomic rearrangements. Of those, double-strand breaks (DSBs) are considered the most harmful and can have lethal consequences for the cells and organism if left unrepaired. DSB repair is accomplished through two major pathways, homologous recombination-guided repair (HR) and non-homologous end joining (NHEJ). DNA-dependent protein kinase (DNA-PK) is a serine/threonine kinase and a key driver of NHEJ repair. It is known that there is a complex network of interactions between the DDR systems and the life cycle of viruses, and that the cellular DDR can either promote or restrict virus growth by directly manipulating viral nucleic acids and by activating signaling pathways that can significantly impact viral life cycles. There appears to be a mixture or positive and negative regulation of virus infection by NHEJ machinery.

Coronaviruses

[0002] Coronaviruses (CoVs) are positive-sense, single-stranded RNA (ssRNA) viruses of the order Nidovirales, in the family Coronaviridae. There are four sub-types of coronaviruses - alpha, beta, gamma and delta - with the Alphacoronaviruses and Betacoronaviruses infecting mostly mammals, including humans. Over the last two decades, three significant novel coronaviruses have emerged which jumped from a non-human mammal hosts to infect humans: the severe acute respiratory syndrome (SARS-CoV-1 ) which appeared in 2002, Middle East respiratory syndrome (MERS-CoV) which appeared in 2012, and COVID-19 (SARS-CoV-2) which appeared in late 2019. By mid-June of 2020, over 7.8 million people are known to have been infected, and over 432,000 people have died. Both numbers likely represent a significant undercount of the devastation wrought by the disease.

COVID-19

[0003] SARS-CoV-2 closely resembles SARS-CoV-1 , the causative agent of SARS epidemic of 2002-03 (Fung, et al, Annu. Rev. Microbiol. 2019. 73:529-57). Severe disease has been reported in approximately 15% of patients infected with SARS-CoV-2, of which one third progress to critical disease (e.g. respiratory failure, shock, or multiorgan dysfunction (Siddiqi, et al, J. Heart and Lung Trans. (2020), doi: https://doi.org/10.1016/j-healun.2020.03.012, Zhou, et al, Lancet 2020; 395: 1054-62. https://doi.org/10.1016/S0140-6736(20)30566-3). Fully understanding the mechanism of viral pathogenesis and immune responses triggered by SARS- CoV-2 would be extremely important in rational design of therapeutic interventions beyond antiviral treatments and supportive care. Much is still being discovered about the various ways that COVID-19 impacts the health of the people that develop it.

[0004] Severe acute respiratory syndrome (SARS)-Corona Virus-2 (CoV-2), the etiologic agent for coronavirus disease 2019 (COVID-19), has caused a pandemic affecting almost eight million people worldwide with a case fatality rate of 2-4% as of June 2020. The virus has a high transmission rate, likely linked to high early viral loads and lack of pre-existing immunity (He, et. al, Nat Med 2020 https://doi.org/10.1038/s41591 -020-0869-5). It causes severe disease especially in the elderly and in individuals with comorbidities. The global burden of COVID-19 is immense, and therapeutic approaches are increasingly necessary to tackle the disease. Intuitive anti-viral approaches including those developed for enveloped RNA viruses like HIV-1 (lopinavir plus ritonavir) and Ebola virus (remdesivir) have been implemented in testing as investigational drugs (Grein et al, NEJM 2020 https://doi.org/10.1056/NEJMoa2007016j Cao, et al, NEJM 2020 DOI: 10.1056/NEJMoa2001282). But given that many patients with severe disease present with immunopathology, host-directed immunomodulatory approaches are also being considered, either in a staged approach or concomitantly with antivirals (Metha, et al, The Lancet 2020;

395(10229) DOI: https://doi.org/10.1016/S0140-6736(20)30628-0, Stebbing, et al, Lancet Infect Dis 2020. https://doi.org/10.1016/S1473-3099(20)30132-8).

[0005] While there are many therapies being considered for use in treatment of COVID-19, there are as yet hardly any approved medications to treat the disease. To date, treatment typically consists only of the available clinical mainstays of symptomatic management, oxygen therapy, with mechanical ventilation for patients with respiratory failure. Thus, there is an urgent need for novel therapies to address the different stages of the SARS-CoV-2 infectious cycle (Siddiqi, et al.).

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 shows a flow diagram illustrating the different steps taken in the testing of antiviral activity of the DNA-PK inhibitor compound.

[0007] Figure 2 shows, for comparative purposes, viability of uninfected cells and those treated with 10 pM remdisivir as a control.

[0008] Figure 3 shows the viability of cells treated with 20 pM peposertib (“NCE-13”) under the same conditions as those of Figure 2.

[0009] Figure 4 shows the Propidium Iodide signal (total red object integrated intensity) of infected cells, uninfected cells, cells treated with 1 or 10 pM remdivisir and 20 pM peposertib (“NCE-13”).

SUMMARY OF THE INVENTION

[0010] In a first embodiment, the invention provides a DNA-PK inhibitor of the invention for use in the treatment of viral infections in a subject in need thereof. In one aspect of this embodiment, the viral infection is a single-strand RNA viral infection. In another aspect of this embodiment, the viral infection is a coronavirus infection. In a further aspect of this embodiment, the viral infection is a SARS-CoV1 , MERS-CoV, or SARS-CoV-2 infection. In a final aspect of this embodiment, the viral infection is a SARS-CoV-2 infection.

[0011] A second embodiment is a method of treating a coronavirus infection in a subject in need thereof, comprising administering an effective amount of a DNA-PK inhibitor, or a pharmaceutically acceptable salt thereof, to the subject. In one aspect of this embodiment, the administration of the DNA-PK inhibitor reduces the viral load in the subject. In one aspect of this embodiment, the DNA-PK inhibitor is administered prior to COVID-19 pneumonia development. In another aspect of this embodiment, the DNA-PK inhibitor is administered prior to the subject developing a severe cytokine storm. In a further aspect of this embodiment, the subject has a mild to moderate SARS-CoV-2 infection. In an additional aspect of this embodiment, the subject is asymptomatic at the start of the administration regimen.

DETAILED DESCRIPTION

[0012] Recent papers have suggested a correlation between SARS-CoV-2 viral load, symptom severity and viral shedding (He, et al; Liu, et al, Lancet Infect Dis 2020. https://doi.org/10.1016/S1473-3099(20)30232-2). Some antiviral drugs administered at symptom onset to blunt coronavirus replication are in the testing phase (Grein, et al), but as yet none have shown much promise. Being able to slow the viral reproduction in the early stages of infection may allow the subject to avoid severe disease.

[0013] Coronaviruses comprise a diverse group of enveloped positive-strand RNA viruses that are responsible for several human diseases, most notably the severe acute respiratory syndrome (SARS) which emerged in 2003. Perturbation of the host cell cycle regulation is a characteristic feature of infections by many DNA and RNA-viruses, including Corona-virus infectious bronchitis virus (IBV) (Xu L.H. et al.: Coronavirus Infection Induces DNA Replication Stress Partly through Interaction of Its Nonstructural Protein 13 with the p125 Subunit of DNA Polymerase; J Biol Chem. Nov 11 ; 286(45): 39546-39559.). IBV infection was shown to induce cell cycle arrest at both S and G2/M phases for the enhancement of viral replication and progeny production. Xu et al. have shown that activation of the cellular DNA damage response is one of the key mechanisms exploited by Coronavirus to induce cell cycle arrest.

[0014] The DNA damage response is mediated by members of the PIKK (phosphatidylinositol-3-kinase-like protein kinase) family of serine/threonine kinases including ATM (ataxia telangiectasia mutated), ATR (ataxia telangiectasia and Rad3 related), and DNA-PK (DNA-dependent protein kinase).

[0015] Xu et al (ibid.) showed that ATR-signaling was activated in IBV-infected H1299 as well as Vero cells. Suppression of the ATR kinase activity by chemical inhibitors and siRNA-mediated knockdown of ATR reduced IBV-induced ATR signaling and inhibited the replication of IBV. On the contrary, ATM pathway activation was not observed and DNA-PK inhibitors did not reduce IBV replication.

[0016] It was not expected that the - albeit potent and selective - DNA-PK inhibitor as shown herein would show such a strong antiviral activity. It is hypothesized that the compound of the invention advantageously interferes with the DNA damage response and/or virus replication. It is conceivable that the DNA-PK inhibitor inhibits the coronavirus induced cell arrest and/or the replication of the coronavirus in the host cell by inhibiting the virus induced activation of cellular DNA damage response. Whatever the exact mechanism of action for the antiviral properties of the compounds of the invention, it is proposed that administration thereof may have one or more clinical benefits, as described further herein. [0017] “COVID-19” is the name of the disease which is caused by a SARS-CoV-2 infection. While care was taken to describe both the infection and disease with accurate terminology, “COVID-19” and “SARS-CoV-2 infection” are meant to be equivalent terms.

[0018] As of the writing of this application, the determination and characteristics of the severity of COVID-19 patients/symptoms has not been definitively established. However, in the context of this invention, “mild to moderate” COVID-19 occurs when the subject presents as asymptomatic or with less severe clinical symptoms (e.g., low grade or no fever (<39.10), cough, mild to moderate discomfort) with no evidence of pneumonia, and generally does not require medical attention. When “moderate to severe” infection is referred to, generally patients present with more severe clinical symptoms (e.g., fever >39.10, shortness of breath, persistent cough, pneumonia, etc.). As used herein “moderate to severe” infection typically requires medical intervention, including hospitalization. During the progression of disease, a subject can transition from “mild to moderate” to “moderate to severe” and back again in one course of bout of infection.

[0019] Treatment of COVID-19 using the methods of this invention include administration of an effective amount of a DNA-PK inhibitor of the invention at any stage of the infection to prevent or reduce the symptoms associated therewith. Typically, subjects will be administered an effective amount of a DNA-PK inhibitor of the invention after definitive diagnosis and presentation with symptoms consistent with a SARS-CoV2 infection, and administration will reduce the severity of the infection and/or prevent progression of the infection to a more severe state. The clinical benefits upon such administration are described in more detail in the sections below.

1. Compounds and Definitions

[0020] One embodiment is use of a compound according to the following formula:

or pharmaceutically acceptable salt thereof for treating a coronavirus infection in a subject in need thereof, as well as a method of treating a coronavirus infection in a subject in need thereof, comprising administering an effective amount of a DNA-PK inhibitor, or a pharmaceutically acceptable salt thereof to the subject.

[0021] The compound according to the above formula may also be designated as (S)-[2- Chloro-4-fluoro-5-(7-morpholin-4-yl-quinazolin-4-yl)-phenyl]-(6-methoxy-pyridazin-3-yl)- methanol, and is also known as peposertib (INN). Its preparation and properties are described in WO 2014/183850.

[0022] The above compound may either be used in its free form or as a pharmaceutically acceptable salt. The free compound may be converted into the associated acid-addition salt by reaction with an acid, for example by reaction of equivalent amounts of the compound and the acid in an inert solvent, such as, for example, ethanol, and subsequent evaporation.

[0023] An exemplary embodiment of a pharmaceutically acceptable salt of the above compound is the fumarate salt. However, salts of other organic or inorganic acids may be used.

[0024] Unless otherwise stated, structures depicted herein are also meant to include compounds that differ only in the presence of one or more isotopically enriched atoms. For example, compounds having the present structures including the replacement of hydrogen by deuterium or tritium, or the replacement of a carbon by a ¹³C- or ¹⁴C-enriched carbon are within the scope of this invention. In some embodiments, the group comprises one or more deuterium atoms.

2. Uses, Formulation and Administration

[0025] The term “patient” or “subject”, as used herein, means an animal, preferably a human. However, “subject” can include companion animals such as dogs and cats. In one embodiment, the subject is an adult human patient. In another embodiment, the subject is a pediatric patient. Pediatric patients include any human which is under the age of 18 at the start of treatment. Adult patients include any human which is age 18 and above at the start of treatment. In one embodiment, the subject is a member of a high-risk group, such as being over 65 years of age, immunocompromised humans of any age, humans with chronic lung conditions (such as, asthma, COPD, cystic fibrosis, etc.), and humans with other co-morbidities. In one aspect of this embodiment, the other co-morbidity is obesity, diabetes, and/or hypertension.

[0026] Compositions of the present invention are administered orally, parenterally, by inhalation spray, topically, rectally, nasally, buccally, vaginally or via an implanted reservoir. Preferably, the compositions are administered orally. In one embodiment, the oral formulation of a compound of the invention is a tablet or capsule form. In another embodiment, the oral formulation is a solution or suspension which may be given to a subject in need thereof via mouth or nasogastric tube. Any oral formulations of the invention may be administered with or without food. In some embodiments, pharmaceutically acceptable compositions of this invention are administered without food. In other embodiments, pharmaceutically acceptable compositions of this invention are administered with food.

[0027] Pharmaceutically acceptable compositions of this invention are orally administered in any orally acceptable dosage form. Exemplary oral dosage forms are capsules, tablets, aqueous suspensions or solutions. In the case of tablets for oral use, carriers commonly used include lactose and corn starch. Lubricating agents, such as magnesium stearate, are also typically added. For oral administration in a capsule form, useful diluents include lactose and dried cornstarch. When aqueous suspensions are required for oral use, the active ingredient is combined with emulsifying and suspending agents. If desired, certain sweetening, flavoring or coloring agents are optionally also added. Suitable pharmaceutically acceptable compositions of peposertib are described in WO 2018/178134, for instance.

[0028] The amount of compound of the present invention that is optionally combined with the carrier materials to produce a composition in a single dosage form will vary depending upon the host treated, the particular mode of administration. Preferably, provided compositions should be formulated so that a dosage of between 0.01 - 100 mg/kg body weight/day of the compound can be administered to a patient receiving these compositions.

[0029] In one embodiment, the total amount of DNA-PK inhibitor administered to the subject in need thereof is between about 5 mg to about 1000 mg per day.

[0030] In one embodiment, the DNA-PK inhibitor is administered in a total amount of 5 mg to 1 g per day, for instance between 10 and 1000 mg per day, such as between 50 and 800 mg per day or between 100 and 400 mg per day.

[0031] In another embodiment, the DNA-PK inhibitor is administered once a day. In another aspect of this embodiment, the DNA-PK inhibitor is administered twice a day.

[0032] In any of the above embodiments, the DNA-PK inhibitor is administered for a period of about 7 days to about 28 days. In one aspect of any of the above embodiments, the DNA-PK inhibitor is administered for about 14 days. [0033] In one embodiment of the invention, the subject is suffering from COVID-19 pneumonia. In one embodiment of this invention, the subject is suffering from one or more symptoms selected from chest congestion, cough, blood oxygen saturation (SpO2) levels below 94%, shortness of breath, difficulty breathing, fever, chills, repeated shaking with chills, muscle pain and/or weakness, headache, sore throat and/or new loss of taste or smell.

[0034] In one embodiment, the subject is suffering from a hyperinflammatory host immune response to a SARS-CoV-2 infection. In one aspect of this embodiment, the hyperinflammatory host immune response is associated with one or more clinical indications selected from 1 ) reduced levels of lymphocytes, especially natural killer (NK) cells in peripheral blood; 2) high levels of inflammatory parameters (eg, C reactive protein [CRP], ferritin, d-dimer), and pro- inflammatory cytokines (eg, IL-6, TNF-alpha, IL-8, and/or IL-1 beta; 3) a deteriorating immune system demonstrated by lymphocytopenia and/or atrophy of the spleen and lymph nodes, along with reduced lymphocytes in lymphoid organs; 4) dysfunction of the lung physiology represented by lung lesions infiltrated with monocytes, macrophages, and/or neutrophils, but minimal lymphocytes infiltration resulting in decreased oxygenation of the blood; 5) acute respiratory distress syndrome (ARDS); 6) vasculitis; 7) encephalitis, Guillain-Barre syndrome, and other neurologic disorders; 8) kidney dysfunction and kidney failure; 9) hypercoagulability such as arterial thromboses; and 10) or any combination of above resulting in end-organ damage and death.

[0035] In one embodiment, the subject with COVID-19 is a pediatric patient suffering from vasculitis, including Kawasaki disease (i.e., Kawasaki syndrome) and Kawasaki-like disease.

[0036] In one embodiment of the invention, the subject is being treated inpatient in a hospital setting. In another embodiment, the subject is being treated in an outpatient setting. In one aspect of the preceding embodiments, the subject may continue administration of the DNA-PK inhibitor after being transitioned from being treated from an inpatient hospital setting to an outpatient setting.

[0037] In one embodiment, the administration of the DNA-PK inhibitor results in one or more clinical benefit. In one aspect of this embodiment, the one or more clinical benefit is selected from the group comprising: reduction of duration of a hospital stay, reduction of the duration of time in the Intensive Care Unit (ICU), reduction in the likelihood of the subject being admitted to an ICU, reduction in the rate of mortality, reduction in the likelihood of kidney failure requiring dialysis, reduction in the likelihood of being put on non-invasive or invasive mechanical ventilation, reduction of the time to recovery, reduction in the likelihood supplemental oxygen will be needed, improvement or normalization in the peripheral capillary oxygen saturation (SpO2 levels) without mechanical intervention, reduction of severity of the pneumonia as determined by chest imaging (eg, CT or chest X ray), reduction in the cytokine production, reduction of the severity of acute respiratory distress syndrome (ARDS), reduction in the likelihood of developing ARDS, clinical resolution of the COVID-19 pneumonia, and improvement of the PaOs/FiOz ratio.

[0038] In another embodiment, the one or more clinical benefits includes the improvement or normalization in the peripheral capillary oxygen saturation (SpO2 levels) in the subject without mechanical ventilation or extracorporeal membrane oxygenation.

[0039] In a further embodiment, the one or more clinical benefits is reduction in the likelihood of being hospitalized, reduction in the likelihood of ICU admission, reduction in the likelihood being intubated (invasive mechanical ventilation), reduction in the likelihood supplemental oxygen will be needed, reduction in the length of hospital stay, reduction in the likelihood of mortality, and/or a reduction in likelihood of relapse, including the likelihood of rehospitalization.

[0040] The invention also provides a method of treating a viral infection in a subject in need thereof comprising administering an effective amount of a compound of the invention to the subject. An amount effective to treat or inhibit a viral infection is an amount that will cause a reduction in one or more of the manifestations of viral infection, such as viral lesions, viral load, rate of virus production, and mortality as compared to untreated control subjects.

[0041] One embodiment of the invention is a method of treating a coronavirus infection in a subject in need thereof, comprising administering an effective amount of an DNA-PK inhibitor, or a pharmaceutically acceptable salt thereof, to the subject. In one aspect of this embodiment, the subject is infected with SARS-CoV-2. In another aspect of this embodiment, the administration of the DNA-PK inhibitor results in the reduction of the viral load in the subject.

[0042] In one embodiment, the DNA-PK inhibitor is administered prior to COVID-19 pneumonia developing. In another embodiment, the subject has a mild to moderate SARS-CoV- 2 infection. In a further embodiment, the subject is asymptomatic at the start of the administration regimen. In another embodiment, the subject has had known contact with a patient who has been diagnosed with a SARS-CoV-2 infection. In an additional embodiment, the subject begins administration of the DNA-PK inhibitor prior to being formally diagnosed with COVID-19.

[0043] One embodiment is a method of treating a subject with COVID-19 comprising administration of an effective amount of a DNA-PK inhibitor to the subject. In one aspect of this embodiment, the subject has been previously vaccinated with a SARS-CoV-2 vaccine and develops vaccine-related exacerbation of infection, for example, an antibody-dependent enhancement or related antibody-mediated mechanisms of vaccine/antibody-related exacerbation.

[0044] In any of the above embodiments, the administration of the DNA-PK inhibitor results in one or more clinical benefits to the subject. In one aspect of this embodiment, the one or more clinical benefits is shortening the duration of infection, reduction of the likelihood of hospitalization, reduction in the likelihood of mortality, reduction in the likelihood of ICll admission, reduction in the likelihood being placed on mechanical ventilation, reduction in the likelihood supplemental oxygen will be needed, and/or reduction in the length of hospital stay. In another aspect of this embodiment, the one or more clinical benefits is avoidance of a significant proinflammatory response. In a further aspect of this embodiment, the one or more clinical benefit is the failure of the subject to develop significant symptoms of COVID-19.

[0045] The compounds of the invention can be administered before or following an onset of SARS-CoV-2 infection, or after acute infection has been diagnosed in a subject. The aforementioned compounds and medical products of the inventive use are particularly used for the therapeutic treatment. A therapeutically relevant effect relieves to some extent one or more symptoms of a disorder, or returns to normality, either partially or completely, one or more physiological or biochemical parameters associated with or causative of a disease or pathological condition. Monitoring is considered as a kind of treatment provided that the compounds are administered in distinct intervals, e.g. in order to boost the response and eradicate the pathogens and/or symptoms of the disease. The methods of the invention can also be used to reduce the likelihood of developing a disorder or even prevent the initiation of disorders associated with COVID-19 in advance of the manifestation of mild to moderate disease, or to treat the arising and continuing symptoms of an acute infection.

[0046] Treatment of mild to moderate COVID-19 is typically done in an outpatient setting. Treatment of moderate to severe COVID-19 is typically done inpatient in a hospital setting. Additionally, treatment can continue in an outpatient setting after a subject has been discharged from the hospital.

[0047] The invention furthermore relates to a medicament comprising at least one compound according to the invention or a pharmaceutically acceptable salt thereof. [0048] A “medicament” in the meaning of the invention is any agent in the field of medicine, which comprises one or more compounds of the invention or preparations thereof (e.g. a pharmaceutical composition or pharmaceutical formulation) and can be used in prophylaxis, therapy, follow-up or aftercare of patients who suffer from clinical symptoms and/or known exposure to COVID-19.

Combination Treatment

[0049] In various embodiments, the active ingredient may be administered alone or in combination with one or more additional therapeutic agents. A synergistic or augmented effect may be achieved by using more than one compound in the pharmaceutical composition. The active ingredients can be used either simultaneously or sequentially.

[0050] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more additional therapeutic agents. In one aspect of this embodiment, the one or more additional therapeutic agents is selected from anti-inflammatories, antibiotics, anti-coagulants, antiparasitic agent, antiplatelet agents and dual antiplatelet therapy, angiotensin converting enzyme (ACE) inhibitors, angiotensin II receptor blockers, beta-blockers, statins and other combination cholesterol lowering agents, specific cytokine inhibitors, complement inhibitors, anti-VEGF treatments, JAK inhibitors, immunomodulators, anti-inflammasome therapies, sphingosine-1 phosphate receptors binders, N-methyl-d-aspartate (NDMA) receptor glutamate receptor antagonists, corticosteroids, Granulocyte-macrophage colony-stimulating factor (GM-CSF), anti- GM-CSF, interferons, angiotensin receptor-neprilysin inhibitors, calcium channel blockers, vasodilators, diuretics, muscle relaxants, and antiviral medications.

[0051] In one embodiment, the DNA-PK inhibitor is administered in combination with an antiviral agent. In one aspect of this embodiment, the antiviral agent is remdesivir. In another aspect of this embodiment, the antiviral agent is lopinavir-ritonavir, alone or in combination with ribavirin and interferon-beta.

[0052] In one embodiment, the DNA-PK inhibitor is administrated in combination with a broadspectrum antibiotic.

[0053] In one embodiment, the DNA-PK inhibitor is administered in combination with chloroquine or hydroxychloroquine. In one aspect of this embodiment, the DNA-PK inhibitor is further combined with azithromycin.

[0054] In one embodiment, the DNA-PK inhibitor is administered in combination with interferon-1 -beta (Rebif®). [0055] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more additional therapeutic agents selected from hydroxychloroquine, chloroquine, ivermectin, tranexamic acid, nafamostat, virazole, ribavirin, lopinavir/ritonavir, favipiravir, arbidol, leronlimab, interferon beta-1 a, interferon beta-1 b, beta-interferon, azithromycin, nitrazoxamide, lovastatin, clazakizumab, adalimumab, etanercept, golimumab, infliximab, sarilumab, tocilizumab, anakinra, emapalumab, pirfenidone, belimumab, rituximab, ocrelizumab, anifrolumab, ravulizumab-cwvz, eculizumab, bevacizumab, heparin, enoxaparin, apremilast, coumadin, baricitinib, ruxolitinib, dapagliflozin, methotrexate, leflunomide, azathioprine, sulfasalazine, mycophenolate mofetil, colchicine, fingolimod, ifenprodil, prednisone, cortisol, dexamethasone, methylprednisolone, melatonin, otilimab, ATR-002, APN-01 , camostat mesylate, brilacidin, IFX-1 , PAX-1 -001 , BXT- 25, NP-120, intravenous immunoglobulin (IVIG), and solnatide.

[0056] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more anti-inflammatory agent. In one aspect of this embodiment, the anti-inflammatory agent is selected from corticosteroids, steroids, COX-2 inhibitors, and non-steroidal anti-inflammatory drugs (NSAID). In one aspect of this embodiment, the anti-inflammatory agent is diclofenac, etodolac, fenoprofen, flurbirprofen, ibuprofen, indomethacin, meclofenamate, mefenamic acid, meloxicam, nabumetone, naproxen, oxaprozin, piroxicam, sulindac, tolmetin, celecoxib, prednisone, hydrocortisone, fludocortisone, bethamethasone, prednisolone, triamcinolone, methylprednisone, dexamethasone, fluticasone, and budesonide (alone or in combination with formoterol, salmeterol, or vilanterol).

[0057] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more immune modulators. In one aspect of this embodiment the immune modulator is a calcineurin inhibitor, antimetabolite, or alkylating agent. In another aspect of this embodiment, the immune modulator is selected from azathioprine, mycophenolate mofetil, methotrexate, dapson, cyclosporine, cyclophosphamide, and the like.

[0058] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more antibiotics. In one aspect of this embodiment, the antibiotic is a broad-spectrum antibiotic. In another aspect of this embodiment, the antibiotic is a penicillin, anti-straphylococcal penicillin, cephalosporin, aminopenicillin (commonly administered with a betalactamase inhibitor), monobactam, quinoline, aminoglycoside, lincosamide, macrolide, tetracycline, glycopeptide, antimetabolite or nitroimidazole. In a further aspect of this embodiment, the antibiotic is selected from penicillin G, oxacillin, amoxicillin, cefazolin, cephalexin, cephotetan, cefoxitin, ceftriazone, augmentin, amoxicillin, ampicillin (plus sulbactam), piperacillin (plus tazobactam), ertapenem, ciprofloxacin, imipenem, meropenem, levofloxacin, moxifloxacin, amikacin, clindamycin, azithromycin, doxycycline, vancomycin, Bactrim, and metronidazole.

[0059] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more anti-coagulants. In one aspect of this embodiment, the anti-coagulant is selected from apixaban, dabigatran, edoxaban, heparin, rivaroxaban, and warfarin.

[0060] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more antiplatelet agents and/or dual antiplatelet therapy. In one aspect of this embodiment, the antiplatelet agent and/or dual antiplatelet therapy is selected from aspirin, clopidogrel, dipyridamole, prasugrel, and ticagrelor.

[0061] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more ACE inhibitors. In one aspect of this embodiment, the ACE inhibitor is selected from benazepril, captopril, enalapril, fosinopril, lisinopril, moexipril, perindopril, quinapril, ramipril and trandolapril.

[0062] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more angiotensin II receptor blockers. In one aspect of this embodiment, the angiotensin II receptor blocker is selected from azilsartan, candesartan, eprosartan, irbesartan, losartan, Olmesartan, telmisartan, and valsartan.

[0063] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more beta-blockers. In one aspect of this embodiment, the beta-blocker is selected from acebutolol, atenolol, betaxolol, bisoprolol/hydrochlorothiazide, bisoprolol, metoprolol, nadolol, propranolol, and sotalol.

[0064] In another embodiment, the DNA-PK inhibitor is administered in combination with one or more alpha and beta-blocker. In one aspect of this embodiment, the alpha and beta-blocker is carvedilol or labetalol hydrochloride.

[0065] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more interferons.

[0066] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more angiotensin receptor-neprilysin inhibitors. In one aspect of this embodiment, the angiotensin receptor-neprilysin inhibitor is sacubitril/valsartan.

[0067] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more calcium channel blockers. In one aspect of this embodiment, the calcium channel blocker is selected from amlodipine, diltiazem, felodipine, nifedipine, nimodipine, nisoldipine, and verapamil.

[0068] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more vasodilators. In one aspect of this embodiment, the one or more vasodilator is selected from isosorbide dinitrate, isosorbide mononitrate, nitroglycerin, and minoxidil.

[0069] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more diuretics. In one aspect of this embodiment, the one or more diuretics is selected from acetazolamide, amiloride, bumetanide, chlorothiazide, chlorthalidone, furosemide, hydrochlorothiazide, indapamide, metolazone, spironolactone, and torsemide.

[0070] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more muscle relaxants. In one aspect of this embodiment, the muscle relaxant is an antispasmodic or antispastic. In another aspect of this embodiment, the one or more muscle relaxants is selected from carisoprodol, chlorzoxazone, cyclobenzaprine, metaxalone, methocarbamol, orphenadrine, tizanidine, baclofen, dantrolene, and diazepam.

[0071] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more antiviral medications. In one aspect of this embodiment, the antiviral medication is remdesivir.

[0072] In one embodiment, the DNA-PK inhibitor is administered in combination with one or more additional therapeutic agents selected from antiparasitic drugs (including, but not limited to, hydroxychloroquine, chloroquine, ivermectin), antivirals (including, but not limited to, tranexamic acid, nafamostat, virazole [ribavirin], lopinavir/ritonavir, favipiravir, leronlimab, interferon beta-1 a, interferon beta-1 b, beta-interferon), antibiotics with intracellular activities (including, but not limited to azithromycin, nitrazoxamide), statins and other combination cholesterol lowering and antiinflammatory drugs (including, but not limited to, lovastatin), specific cytokine inhibitors (including, but not limited to, clazakizumab, adalimumab, etanercept, golimumab, infliximab, sarilumab, tocilizumab, anakinra, emapalumab, pirfenidone), complement inhibitors (including, but not limited to, ravulizumab-cwvz, eculizumab), anti-VEGF treatments (including, but not limited to, bevacizumab), anti-coagulants (including, but not limited to, heparin, enoxaparin, apremilast, coumadin), JAK inhibitors (including, but not limited to, baricitinib, ruxolitinib, dapagliflozin), anti- inflammasome therapies (including, but not limited to, colchicine), sphingosine-1 phosphate receptors binders (including, but not limited to, fingolimod), N-methyl-d-aspartate (NDMA) receptor glutamate receptor antagonists (including, but not limited to, ifenprodil), corticosteroids (including, but not limited to, prednisone, cortisol, dexamethasone, methylprednisolone), GM- CSF, anti-GM-CSF (otilimab), ATR-002, APN-01 , camostat mesylate, arbidol, brilacidin, IFX-1 , PAX-1 -001 , BXT-25, NP-120, intravenous immunoglobulin (IVIG), and solnatide.

[0073] In some embodiments, the combination of an DNA-PK inhibitor with one or more additional therapeutic agents reduces the effective amount (including, but not limited to, dosage volume, dosage concentration, and/or total drug dose administered) of the DNA-PK inhibitor and/or the one or more additional therapeutic agents administered to achieve the same result as compared to the effective amount administered when the DNA-PK inhibitor or the additional therapeutic agent is administered alone. In some embodiments, the combination of an DNA-PK inhibitor with the additional therapeutic agent reduces the total duration of treatment compared to administration of the additional therapeutic agent alone. In some embodiments, the combination of an DNA-PK inhibitor with the additional therapeutic agent reduces the side effects associated with administration of the additional therapeutic agent alone. In some embodiments, the combination of an effective amount of the DNA-PK inhibitor with the additional therapeutic agent is more efficacious compared to an effective amount of the DNA-PK inhibitor or the additional therapeutic agent alone. In one embodiment, the combination of an effective amount of the DNA- PK inhibitor with the one or more additional therapeutic agent results in one or more additional clinical benefits than administration of either agent alone.

[0074] As used herein, the terms “treatment,” “treat,” and “treating” refer to reversing, alleviating, delaying the onset of, or inhibiting the progress of a viral infection, or one or more symptoms thereof, as described herein. In some embodiments, treatment is administered after one or more symptoms have developed. In other embodiments, treatment is administered in the absence of symptoms. For example, treatment is administered to a susceptible individual prior to the onset of symptoms (e.g., in light of a known exposure to an infected person and/or in light of comorbidities which are predictors for severe disease, or other susceptibility factors).

EXEMPLIFICATION

[0075] As described in detail in the Example below and illustrated by the Figures, the DNA- PK inhibitor peposertib (referred to as “NCE-13” in the Figures) was tested for antiviral effect using Vero E6 cells.

Example: Antiviral testing of Compound

Cell culture and Viruses

[0076] Vero E6 (ATCC CRL-1586) cells were maintained in DMEM medium supplemented with 10% fetal calf serum (FCS), 2 mM L-glutamine, 100 ILI/mL penicillin and 100 pg/mL streptomycin. All incubations of cells and virus were at 37 G in a 5% CO2 atmosphere. The SARS-CoV-2 strains used was a Zagreb isolate.

SARS-CoV-2 infection

[0077] The activity of compounds on SARS-CoV-2 infection were tested by seeding Vero E6 cells at a density of 7 x 10³ cells in 384 - well plates one day before infection. On the day of infection, propidium iodide (1 pg/mL) was added to the cell monolayer followed by addition of peposertib at 20 pM. Vero E6 cell monolayer was infected 1 h after addition of compounds by SARS-CoV-2 with an MOI (multiplicity of infection) of 0.01 in 50 pL and incubated at 37 G for 72 h. The total infection volume per well was 50 pL.

Data analysis

[0078] Images were taken automatically using a Sartorius IncuCyte S3 (10x objective, two hours image intervals, 4 images per well) housed in a HeraCell 150i incubator (370, 100% humidity, 5% CO2). Image data was quantified with the IncuCyte S3 GUI tools analyzed with GraphPad Prism 8.

[0079] Viability of cells was determined after 72 h of infection by using the CellTiter-Glo Luminescent Cell Viability Assay (Promega Inc.). CellTiter-Glo reagents were prepared according to manufacturer protocol. The reaction was initiated by addition of 50 pL/well of the CellTiter-Glo reagent to cells. Assay plates were incubated for 10 min in the dark at RT prior to measurement. Luminescence was detected on the Synergy HTX Multi-Mode plate reader (Biotek). Data analysis was performed using Graphpad Prism 8.

[0080] The above steps are illustrated in the flow diagram depicted in Figure 1 . As apparent from Figures 2 to 4, which show the results of viability and propidium iodide signal measurements, the DNA-PK inhibitor (“NCE-13”) compound peposertib showed a strong antiviral response against CoV-2 and compares favourably with remdisivir.

Claims

CLAIMS A method of treating a coronavirus infection in a subject in need thereof, comprising administering an effective amount of a DNA-PK inhibitor, or a pharmaceutically acceptable salt thereof, to the subject. The method of claim 1 , wherein the coronavirus causes a SARS or MERS infection. The method of claim 1 or 2, wherein the coronavirus causes a SARS-CoV-1 or SARS- CoV-2 or MERS-CoV infection. The method of any one of claims 1 -3, wherein the coronavirus is SARS-CoV-2. The method of any one of claims 1 -4, wherein the DNA-PK inhibitor is or a pharmaceutically acceptable salt thereof. The method of any one of claims 1 -5, wherein the administration of the DNA-PK inhibitor results in the reduction of the viral load in the subject. The method of any one of claims 1 -5, wherein the DNA-PK inhibitor reduces or inhibits the virus induced activation of the DNA damage response in the infected cells. The method of any one of the preceding claims, wherein the DNA-PK inhibitor is administered prior to COVID-19 pneumonia development. The method of any one of the preceding claims, wherein the subject has a mild to moderate SARS-CoV-2 infection. The method of any one of the preceding claims, wherein the subject has been previously vaccinated with a SARS-CoV-2 vaccine and develops vaccine-related exacerbation of infection, for example, an antibody-dependent enhancement or related antibody- mediated mechanisms of vaccine/antibody-related exacerbation.

1 . The method of any one of claims 1 -10, wherein the subject is asymptomatic at the start of the treatment.

2. The method of any one of claims 1 -10, wherein the subject has had known contact with a patient who has been diagnosed with a SARS-CoV-2 infection.

3. The method of any one of claims 1 -10, wherein the subject begins administration of the DNA-PK inhibitor prior to being formally diagnosed with SARS-CoV-2 infection.

4. The method of any one of claims 1 -10, wherein the administration of the DNA-PK inhibitor results in one or more clinical benefits.

5. The method of claim 14, wherein the one or more clinical benefits is selected from: shortening the duration of infection, reduction of the likelihood of hospitalization, reduction in the likelihood of mortality, reduction in the likelihood of ICll admission, reduction in the likelihood being placed on mechanical ventilation, reduction in the likelihood supplemental oxygen will be needed, and/or reduction in the length of hospital stay.

6. The method of any one of the preceding claims, wherein the subject is undergoing outpatient treatment.

7. The method of any one of the preceding claims, further comprising administration of one or more additional therapeutic agent.

8. The method of claim 17, wherein the one or more additional therapeutic agents is selected from anti-inflammatories, antibiotics, anti-coagulants, antiparasitic agent, antiplatelet agents and dual antiplatelet therapy, angiotensin converting enzyme (ACE) inhibitors, angiotensin II receptor blockers, beta-blockers, statins and other combination cholesterol lowering agents, specific cytokine inhibitors, complement inhibitors, anti- VEGF treatments, JAK inhibitors, immunomodulators, anti-inflammasome therapies, sphingosine-1 phosphate receptors binders, N-methyl-d-aspartate (NDMA) receptor glutamate receptor antagonists, corticosteroids, Granulocyte-macrophage colonystimulating factor (GM-CSF), anti-GM-CSF, interferons, angiotensin receptor-neprilysin inhibitors, calcium channel blockers, vasodilators, diuretics, muscle relaxants, and antiviral medications.

9. The method of claim 17, wherein the one or more additional therapeutic agents is an antiviral medication. The method of claim 17, wherein the one or more additional therapeutic agents is remdesivir. The method of claim 17, wherein the one or more additional therapeutic agents is lopinavir-ritonavir. The method of claim 17, wherein the one or more additional therapeutic agents further includes ribavirin and interferon-beta. The method of claim 17, wherein the one or more additional therapeutic agents is chloroquine or hydroxychloroquine. The method of claim 17, wherein the one or more additional therapeutic agents further includes azithromycin. The method of claim 17, wherein the one or more additional therapeutic agents is interferon-1 -beta (Rebif®). The method of claim 17, wherein the one or more additional therapeutic agent is selected from hydroxychloroquine, chloroquine, ivermectin, tranexamic acid, nafamostat, virazole [ribavirin], lopinavir/ritonavir, favipiravir, leronlimab, interferon betal a, interferon beta-1 b, beta-interferon, azithromycin, nitrazoxamide, lovastatin, clazakizumab, adalimumab, etanercept, golimumab, infliximab, sarilumab, tocilizumab, anakinra, emapalumab, pirfenidone, ravulizumab-cwvz, eculizumab, bevacizumab, heparin, enoxaparin, apremilast, coumadin, baricitinib, ruxolitinib, dapagliflozin, colchicine, fingolimod, ifenprodil, prednisone, cortisol, dexamethasone, methylprednisolone, GM-CSF, otilimab, ATR-002, APN-01 , camostat mesylate, arbidol, brilacidin, IFX-1 , PAX-1 -001 , BXT-25, NP-120, intravenous immunoglobulin (IVIG), and solnatide. The method of any one of the preceding claims, wherein the DNA-PK inhibitor is administered daily. The method of any one of the preceding claims, wherein the total amount of DNA-PK inhibitor administered is between about 10 mg and about 800 mg per day. The method of any one of the preceding claims, wherein the DNA-PK inhibitor is administered for about 7 days to about 21 days. The method of any one of the preceding claims, wherein the DNA-PK inhibitor is administered via oral administration.