Targeting ectromelia virus and TNF/NF-κB or STAT3 signaling for effective treatment of viral pneumonia.

Viral causes of pneumonia pose constant threats to global public health, but there are no specific treatments currently available for the condition. Antivirals are ineffective when administered late after the onset of symptoms. Pneumonia is caused by an exaggerated inflammatory cytokine response to infection, but tissue necrosis and damage caused by virus also contribute to lung pathology. We hypothesized that viral pneumonia can be treated effectively if both virus and inflammation are simultaneously targeted. Combined treatment with the antiviral drug cidofovir and etanercept, which targets tumor necrosis factor (TNF), down-regulated nuclear factor kappa B-signaling and effectively reduced morbidity and mortality during respiratory ectromelia virus (ECTV) infection in mice even when treatment was initiated after onset of clinical signs. Treatment with cidofovir alone reduced viral load, but animals died from severe lung pathology. Treatment with etanercept had no effect on viral load but diminished levels of inflammatory cytokines and chemokines including TNF, IL-6, IL-1ß, IL-12p40, TGF-ß, and CCL5 and dampened activation of the STAT3 cytokine-signaling pathway, which transduces signals from multiple cytokines implicated in lung pathology. Consequently, combined treatment with a STAT3 inhibitor and cidofovir was effective in improving clinical disease and lung pathology in ECTV-infected mice. Thus, the simultaneous targeting of virus and a specific inflammatory cytokine or cytokine-signaling pathway is effective in the treatment of pneumonia. This approach might be applicable to pneumonia caused by emerging and re-emerging viruses, like seasonal and pandemic influenza A virus strains and severe acute respiratory syndrome coronavirus 2.

NPP-669, a prodrug of cidofovir, is highly efficacious against human adenovirus infection in the permissive Syrian hamster model.

Human adenoviruses can cause serious, disseminated infections in immunocompromised patients. For pediatric allogeneic stem cell transplant patients, the case fatality rate can reach 80%. Still, there is no available antiviral drug that is specifically approved by the Food and Drug Administration for the treatment of adenovirus infections. To fill this pressing medical need, we have developed NPP-669, a prodrug of cidofovir with broad activity against double-stranded DNA viruses, including adenoviruses. Here, we report on the in vivo anti-adenoviral efficacy of NPP-669. Using the immunosuppressed Syrian hamster as the model, we show that NPP-669 is highly efficacious when dosed orally at 1 mg/kg and 3 mg/kg. In a delayed administration experiment, NPP-669 was more effective than brincidofovir, a similar compound that reached Phase III clinical trials. Furthermore, parenteral administration of NPP-669 increased its efficacy approximately 10-fold compared to oral dosing without apparent toxicity, suggesting that this route may be preferable in a hospital setting. Based on these findings, we believe that NPP-669 is a promising new compound that needs to be further investigated.

Cidofovir for Viral Infections in Immunocompromised Children: Guidance on Dosing, Safety, Efficacy, and a Review of the Literature.

OBJECTIVE: To describe the use of cidofovir (CDV) for viral infections in immunocompromised children (IC) and provide guidance on dosing and supportive care. DATA SOURCES: A PubMed search was conducted for literature published between 1997 and January 2022 using the following terms: cidofovir, plus children or pediatrics. STUDY SELECTION AND DATA EXTRACTION: Limits were set to include human subjects less than 24 years of age receiving intravenous (IV) or intrabladder CDV for treatment of infections due to adenovirus, polyomavirus-BK (BKV), herpesviruses, or cytomegalovirus. DATA SYNTHESIS: Data were heterogeneous, with largely uncontrolled studies. Conventional dosing (CDV 5 mg/kg/dose weekly) was commonly used in 60% (31/52) of studies and modified dosing (CDV 1 mg/kg/dose 3 times/week) was used in 17% (9/52) of studies, despite being off-label. Nephrotoxicity reported across studies totaled 16% (65/403 patients), which was higher for conventional dosing 29 of 196 patients (15%) than modified dosing 1 of 27 patients (4%). Saline hyperhydration and concomitant probenecid remain the cornerstones of supportive care, while some regimens omitting probenecid are emerging to target BKV. RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE: To our knowledge, this is the first comprehensive review of CDV use (indications, dosing, supportive care, response, and nephrotoxicity) in pediatric IC. CONCLUSIONS: Effective utilization of CDV in IC remains challenging. Further prospective studies are needed to determine the optimal CDV dosing; however, less aggressive dosing regimens such as modified thrice weekly dosing or low dosing once weekly omitting probenecid to enhance urinary penetration may be reasonable alternatives to conventional dosing in some IC.

Treatment and Vaccination for Smallpox and Monkeypox.

The smallpox infection with the variola virus was one of the most fatal disorders until a global eradication was initiated in the twentieth century. The last cases were reported in Somalia 1977 and as a laboratory infection in the UK 1978; in 1980, the World Health Organization (WHO) declared smallpox for extinct. The smallpox virus with its very high transmissibility and mortality is still a major biothreat, because the vaccination against smallpox was stopped globally in the 1980s. For this reason, new antivirals (cidofovir, brincidofovir, and tecovirimat) and new vaccines (ACAM2000, LC16m8 and Modified Vaccine Ankara MVA) were developed. For passive immunization, vaccinia immune globulin intravenous (VIGIV) is available. Due to the relationships between orthopox viruses such as vaccinia, variola, mpox (monkeypox), cowpox, and horsepox, the vaccines (LC16m8 and MVA) and antivirals (brincidofovir and tecovirimat) could also be used in the mpox outbreak with positive preliminary data. As mutations can result in drug resistance against cidofovir or tecovirimat, there is need for further research. Further antivirals (NIOCH-14 and ST-357) and vaccines (VACΔ6 and TNX-801) are being developed in Russia and the USA. In conclusion, further research for treatment and prevention of orthopox infections is needed and is already in progress. After a brief introduction, this chapter presents the smallpox and mpox disease and thereafter full overviews on antiviral treatment and vaccination including the passive immunization with vaccinia immunoglobulins.

Intralesional cidofovir vs. bevacizumab for recurrent respiratory papillomatosis: a systematic review and indirect meta-analysis.

BACKGROUND: Specific HPV types cause recurrent respiratory papillomatosis (R.R.P.). When administered intralesionally, cidofovir, an antiviral agent, has shown favorable outcomes in reducing papilloma. Bevacizumab, an angiogenesis inhibitor, has demonstrated improved R.R.P. However, both treatments lack FDA approval for R.R.P. Our study aims to evaluate the efficacy and safety of intralesional Cidofovir and Bevacizumab for R.R.P. and compare the two interventions. METHODS: We searched five electronic databases to find relevant studies. After the screening, data were extracted from the included studies. Pooled ratios with 95% confidence intervals (CIs) were used for categorical outcomes, and mean difference (MD) was used for continuous outcomes. Statistical heterogeneity was evaluated using the chi-squared test for I2 statistics. The Cochrane Risk of Bias assessment tool was used to assess the methodological quality of randomized controlled trials (RCTs), while the National Institutes of Health's tool was used for observational studies. Analysis was done by Review Manager software. RESULTS: In our comprehensive meta-analysis of 35 articles involving 836 patients, cidofovir demonstrated an overall remission ratio of (0.90 [95% CI: 0.83, 0.98], p = 0.01), while bevacizumab (0.92 [95% CI: 0.79, 1.07]), p = 0.3). The complete remission ratio for cidofovir was (0.66 [95% CI: 0.57, 0.75], p > 0.0001), while bevacizumab was (0.29 [95% CI: 0.12, 0.71], p = 0.07). In partial remission, Bevacizumab showed a higher ratio than Cidofovir 0.74 [0.55, 0.99] vs. 0.40 [0.30, 0.54]. Bevacizumab had a pooled ratio of 0.07 [95% CI: 0.02, 0.30] in terms of no remission, indicating better outcomes compared to Cidofovir with a ratio of 0.28 [95% CI: 0.16, 0.51]. Additionally, Cidofovir showed a favorable decrease in the Derkay Severity Score (DSS) with a mean difference (MD) of 1.98 [95% CI: 1.44, 2.52]. CONCLUSION: Cidofovir had a higher impact on complete remission compared to Bevacizumab. Both showed partial remission, with Bevacizumab having a higher ratio. Moreover, Cidofovir showed a significant decrease in DSS. Bevacizumab had lower rates of no remission and recurrence and fewer adverse events compared to Cidofovir. However, the difference between the two treatments was not significant, except for partial remission.

Combined Effect of Basic Antiherpetic Drugs with a New Inhibitor of the Terminase Complex of Herpes Simplex Virus Type 1 in Vero Cell Cultures.

Carriers of herpes simplex virus type 1 (HSV-1) account for more than 90% of the global population. Infection manifests itself in the formation of blisters and ulcers on the face or genitals and can cause blindness, encephalitis, and generalized infection. All first- and second-line modern antiherpetic drugs selectively inhibit viral DNA polymerase. The purine-benzoxazine conjugate LAS-131 ((S)-4-[6-(purin-6-yl)aminohexanoyl]-7,8-difluoro-3,4-dihydro-3-methyl-2H-[1,4]benzoxazine), which we have described earlier, uses the large subunit of the HSV-1 terminase complex as a biotarget and selectively inhibits HSV-1 reproduction in vitro. Basically new results were for the first time obtained to characterize the combined effect on human herpesvirus infection for LAS-131 used in combination with practically significant antiviral compounds, including the nucleoside analogs acyclovir (ACV), penciclovir (PCV), ganciclovir (GCV), brivudine (BVdU), iododeoxyuridine (IdU), and adenine arabinoside (Ara-A); the nucleoside phosphonate analog cidofovir (CDV); and the pyrophosphate analog foscarnet (FOS). A cytopathic effect (CPE) inhibition assay showed that the drug concentration that inhibited the virus-induced CPE by 50% decreased by a factor of 2 (an additive effect, FOS) or more (a synergistic effect; ACV, PCV, GCV, IdU, BVdU, Ara-A, and CDV) when the drugs were used in combination with LAS-131. Nonpermissive conditions for HSV-1 reproduction were thus created at lower drug concentrations, opening up new real possibilities to control human herpesvirus infection.

Antivirals With Activity Against Mpox: A Clinically Oriented Review.

Mpox virus is an emergent human pathogen. While it is less lethal than smallpox, it can still cause significant morbidity and mortality. In this review, we explore 3 antiviral agents with activity against mpox and other orthopoxviruses: cidofovir, brincidofovir, and tecovirimat. Cidofovir, and its prodrug brincidofovir, are inhibitors of DNA replication with a broad spectrum of activity against multiple families of double-stranded DNA viruses. Tecovirimat has more specific activity against orthopoxviruses and inhibits the formation of the extracellular enveloped virus necessary for cell-to-cell transmission. For each agent, we review basic pharmacology, data from animal models, and reported experience in human patients.

Monkeypox: Virology, laboratory diagnosis and therapeutic approach.

Monkeypox infection outbreaks have been observed sporadically in Africa, usually as a result of interaction with wildlife reservoirs. The genomes of the new strain range in size from 184.7 to 198.0 kb and are identified with 143-214 open reading frames. Viral cores are rapidly carried on microtubules away from the cell's perimeter and deeper into the cytoplasm once the virus and cell membranes fuse. Depending on the kind of exposure, patients with monkeypox may experience a febrile prodrome 5-13 days after exposure, which frequently includes lymphadenopathy, malaise, headaches, and muscle aches. A different diagnostic approach is available for monkeypox, including histopathological analysis, electron microscopy, immunoassays, polymerase chain reaction, genome sequencing, microarrays, loop-mediated isothermal amplification technology and CRISPR (i.e., "clustered regularly interspaced short palindromic repeats"). There are currently no particular, clinically effective treatments available for the monkeypox virus. An initial treatment is cidofovir. As a monophosphate nucleotide analog, cidofovir is transformed into an inhibitor of viral DNA polymerase by cellular kinases, which is analogous to cidofovir's function in inhibiting viral DNA synthesis. The European Medicine Agency and the Food and Drug Administration have both granted permission for IMVAMUNE, a replication-deficient, attenuated third-generation modified vaccinia Ankara vaccine, to be used for the prevention of smallpox and monkeypox in adults.

Repurposing of the antibiotic nitroxoline for the treatment of mpox.

The antiviral drugs tecovirimat, brincidofovir, and cidofovir are considered for mpox (monkeypox) treatment despite a lack of clinical evidence. Moreover, their use is affected by toxic side-effects (brincidofovir, cidofovir), limited availability (tecovirimat), and potentially by resistance formation. Hence, additional, readily available drugs are needed. Here, therapeutic concentrations of nitroxoline, a hydroxyquinoline antibiotic with a favourable safety profile in humans, inhibited the replication of 12 mpox virus isolates from the current outbreak in primary cultures of human keratinocytes and fibroblasts and a skin explant model by interference with host cell signalling. Tecovirimat, but not nitroxoline, treatment resulted in rapid resistance development. Nitroxoline remained effective against the tecovirimat-resistant strain and increased the anti-mpox virus activity of tecovirimat and brincidofovir. Moreover, nitroxoline inhibited bacterial and viral pathogens that are often co-transmitted with mpox. In conclusion, nitroxoline is a repurposing candidate for the treatment of mpox due to both antiviral and antimicrobial activity.

Assessment of immunomodulation and regulation of cell cycle in epithelium and stroma after Cidofovir injection in patients with recurrent respiratory papillomatosis-Pilot study.

Recurrent respiratory papillomatosis is strictly connected with human papillomavirus (HPV) infection of the epithelium of the upper respiratory tract. The main treatment of lesions located in the larynx or lower pharynx includes microsurgical excision by using a CO2 laser. To decrease the amount of surgical procedures gain in importance combined therapy with antiviral agents. The aim of this study was to investigate the effect of the intralesional application of Cidofovir on the tissue of laryngeal papillomas. We have shown that simultaneous microsurgery with adjuvant therapy of Cidofovir reduces chronic inflammation (by measuring the expression of CD4 and CD8 in tissue samples), cell proliferation, and regulates the cell cycle of HPV-infected cells by reducing the expression of p53 and p63 proteins. In addition, this strategy reduces the multiple surgical procedures and regrowth of the pathology.

Monkeypox outbreak 2022: What we know so far and its potential drug targets and management strategies.

Monkeypox is a rare zoonotic disease caused by infection with the monkeypox virus. The disease can result in flu-like symptoms, fever, and a persistent rash. The disease is currently spreading throughout the world and prevention and treatment efforts are being intensified. Although there is no treatment that has been specifically approved for monkeypox virus infection, infected patients may benefit from using certain antiviral medications that are typically prescribed for the treatment of smallpox. The drugs are tecovirimat, brincidofovir, and cidofovir, all of which are currently in short supply due to the spread of the monkeypox virus. Resistance is also a concern, as widespread replication of the monkeypox virus can lead to mutations that produce monkeypox viruses that are resistant to the currently available treatments. This article discusses monkeypox disease, potential drug targets, and management strategies to overcome monkeypox disease. With the discovery of new drugs, it is hoped that the problem of insufficient drugs will be resolved, and it is not anticipated that drug resistance will become a major issue in the near future.

NPP-669, a Novel Broad-Spectrum Antiviral Therapeutic with Excellent Cellular Uptake, Antiviral Potency, Oral Bioavailability, Preclinical Efficacy, and a Promising Safety Margin.

DNA viruses are responsible for many diseases in humans. Current treatments are often limited by toxicity, as in the case of cidofovir (CDV, Vistide), a compound used against cytomegalovirus (CMV) and adenovirus (AdV) infections. CDV is a polar molecule with poor bioavailability, and its overall clinical utility is limited by the high occurrence of acute nephrotoxicity. To circumvent these disadvantages, we designed nine CDV prodrug analogues. The prodrugs modulate the polarity of CDV with a long sulfonyl alkyl chain attached to one of the phosphono oxygens. We added capping groups to the end of the alkyl chain to minimize ß-oxidation and focus the metabolism on the phosphoester hydrolysis, thereby tuning the rate of this reaction by altering the alkyl chain length. With these modifications, the prodrugs have excellent aqueous solubility, optimized metabolic stability, increased cellular permeability, and rapid intracellular conversion to the pharmacologically active diphosphate form (CDV-PP). The prodrugs exhibited significantly enhanced antiviral potency against a wide range of DNA viruses in infected human foreskin fibroblasts. Single-dose intravenous and oral pharmacokinetic experiments showed that the compounds maintained plasma and target tissue levels of CDV well above the EC50 for 24 h. These experiments identified a novel lead candidate, NPP-669. NPP-669 demonstrated efficacy against CMV infections in mice and AdV infections in hamsters following oral (p.o.) dosing at a dose of 1 mg/kg BID and 0.1 mg/kg QD, respectively. We further showed that NPP-669 at 30 mg/kg QD did not exhibit histological signs of toxicity in mice or hamsters. These data suggest that NPP-669 is a promising lead candidate for a broad-spectrum antiviral compound.

Human monkeypox: epidemiology, transmission, pathogenesis, immunology, diagnosis and therapeutics.

"Zoonoses" describe diseases that may be acquired by humans from animals. Due to the constant contact between humans and other animals, many infectious diseases are disseminated. This may happen via direct contact, such as bites or scratches, or by indirect contact, such as when eating bush meat or using contaminated animal parts. Monkeypox disease is one such zoonotic infection which is now emerging as a disease of global concern, and the World Health Organization has already labelled it a public health emergency. The virus is related to other orthopox viruses and may be further classified into two genetically separate clades, the West African and the Central African. The latter is far more pathogenic than the former. Utilizing virotransducer and virostealth proteins, the virus is able to control the host's T-cell-mediated responses and impede the release of cytokines and chemokines.Monkeypox may be treated with tecovirimat, cidofovir, or brincidofovir, and prevention with the vaccination JYNNEOS is recommended. The disease's fast global expansion warrants concern despite the fact that it is less fatal than that caused by the variola virus. Before the sickness reaches catastrophic proportions, we must draw on our prior experiences and act prudently. This article serves as an introduction to the monkeypox virus and its associated pathology, treatments, diagnostics, and preventative measures.

Cidofovir for treating complicated monkeypox in a man with acquired immune deficiency syndrome.

In July 23, the World Health Organization (WHO) declared monkeypox (MPX) a global health emergency of international concern given its rapid spread. So far, most current MPX outbreaks have involved young men who have sex with men (MSM), although with overall mild, self-limiting clinical manifestations. We aim to describe the case of an HIV positive young MSM whose status of immune compromission probably contributed to a more severe clinical course of MPX disease, thus requiring hospitalization and antiviral treatment. He was effectively treated with Cidofovir that may be considered as a valuable component of a multi-faceted management of severe MPX.

Human monkeypox outbreak: Epidemiological data and therapeutic potential of topical cidofovir in a prospective cohort study.

BACKGROUND: Human monkeypox has become increasingly frequent worldwide since the outbreak was first reported in May 2022. OBJECTIVES: As cidofovir is effective against vaccinia and other Orthopoxvirus diseases, we hypothesize that its topical use could be an effective treatment for monkeypox skin lesions, avoiding the adverse effects of systemic administration. METHODS: We conducted a prospective study to collect data on the clinical and virologic course of patients with monkeypox. All patients were offered symptomatic treatment. They were also offered treatment with topical cidofovir on a compassionate use basis. Twelve patients received treatment with topical cidofovir 1%, while the others received only symptomatic treatment. Prospective visits were scheduled for the collection of clinical and virological data. RESULTS: Lesions cleared quicker in the cidofovir-treated group (hazard ratio, 4.572; P = .0039). The median time to resolution was 12 (11.5-15) and 18 (16-21) days, respectively. On day 14, polymerase chain reaction-positive skin lesions were detected in 10% of the cidofovir sample, compared with 62.5% of the non-treated group (P = .019). Local adverse effects were frequent (50%), especially in the anogenital region. No systemic adverse effects were reported. LIMITATIONS: The study is not a clinical trial and lacks a placebo-controlled arm. DISCUSSION: Topical cidofovir is a potentially relevant therapy in patients with skin lesions but mild systemic involvement. Reducing time to resolution could shorten isolation time and improve the cosmetic impact in areas such as the face.

Adenovirus infection in allogeneic hematopoietic cell transplantation.

Adenovirus (AdV) infection occurs in 0-20% of patients in the first 3-4 months after allogeneic hematopoietic cell transplantation (HCT), being higher in pediatric than in adult patients. About 50% of AdV infections involve the blood, which in turn, correlates with an increased risk developing AdV diseases, end-organ damage, and 6-month overall mortality. The main risk factors for AdV infection are T-cell depletion of the graft by ex vivo selection procedures or in vivo use of alemtuzumab or antithymocyte serum, development of graft versus host disease (GVHD) grade III-IV, donor type (haploidentical or human leucocyte antigen mismatched related donor > cord blood> unrelated matched donor) and severe lymphopenia (<0.2 × 109 /L). The prevention of AdV disease relies on early diagnosis of increasing viral replication in blood or stool and the pre-emptive start of cidofovir as viral load exceeds the threshold of ≥102-3 copies/mL in blood and/or 106 copies/g stool in the stool. Cidofovir (CDV), a cytosine monophosphate nucleotide analog, is currently the only antiviral recommended for AdV infection despite limited efficacy and moderate risk of nephrotoxicity. Brincidofovir, a lipid derivative of CDV with more favorable pharmacokinetics properties and superior efficacy, is not available and currently is being investigated for other viral infections. The enhancement of virus-specific T-cell immunity in the first few months post-HCT by the administration of donor-derived or third-party-donor-derived virus-specific T-cells represents an innovative and promising modality of intervention and data of efficacy and safety of the ongoing prospective randomized studies are eagerly awaited.

Adenovirus infection diagnosed by metagenomic next-generation sequencing after haploidentical hematopoietic stem cell transplantation: A multicenter study in China.

OBJECTIVE: This study aims to observe and analyze the clinical characteristics and prognosis of adenovirus (ADV) infection diagnosed by metagenomic next-generation sequencing (mNGS) after haploidentical hematopoietic stem cell transplantation (Haplo-HSCT), which was performed following Beijing Protocol. METHODS: The clinical data of patients who developed ADV infection diagnosed by mNGS after Haplo-HSCT between January 2019 and March 2021, recorded in three transplantation centers, were retrospectively analyzed. Potential risk factors for infection and the clinical manifestations of ADV involvement in different end-organs were also studied. Additionally, the patient prognosis regarding the available treatment was observed. RESULTS: A total of seven patients were diagnosed with ADV infection by the mNGS technique after Haplo-HSCT of 976 patients enrolled. The risk factors for infection included antithymocyte globulin steroid-refractory graft-versus-host disease (GVHD) history, CD25 monoclonal antibody or ruxolitinib treatment history and <300 cells/µL of CD3+ T cells count in peripheral blood. The clinical manifestations of ADV infection included encephalitis, hepatitis, cystitis, and pneumonia. Six patients were treated with cidofovir (CDV) and intravenous immunoglobulin (IVIg), and one with CDV, ribavirin, IVIg, thymosin Alpha-1 for injection and low-dose donor lymphocyte infusion. One case showed negative ADV DNA results with improved conditions; however, the patient died of the relapse of the primary disease in the later stage. The remaining six died of ADV infection. CONCLUSION: mNGS can provide screening for ADV and information on ADV subtypes, helpful to understand tissue tropism. This technique could be useful in diagnosing patients at high risk for ADV infection. ADV infection can involve multiple organs, has difficulty in early diagnosis, and has a poor prognosis. Currently, effective treatments are inadequate.

Lack of clinical evidence of antiviral therapy for human monkeypox: A scoping review.

Since May 2022, many human monkeypox cases have been reported from non-endemic countries. This systematic review aimed to evaluate and summarize the existing research on the efficacy and safety of tecovirimat, brincidofovir, and cidofovir for patients with monkeypox. We searched studies that reported the efficacy and adverse events of tecovirimat, brincidofovir, or cidofovir for patients with human monkeypox in several databases including preprint servers. Only five studies were included. The efficacy and adverse events were assessed in only five and four patients, respectively. Regarding tecovirimat, all two patients recovered from monkeypox. One had no adverse event and the other has no description of an adverse event. Regarding brincidofovir, all three patients recovered from monkeypox but all of them had increased alanine transaminase, and one had nausea and abdominal discomfort. There was no study on treatment with cidofovir. Based on past studies and our results, tecovirimat might be the best choice due to ease of administration (oral drug), fewer side effects, and past treatment results for human monkeypox administration. However, very few studies were included in this scoping review. Therefore, further studies are needed to assess their efficacy and safety as possible treatments for human monkeypox.

Daily low dose intravesical cidofovir for the treatment of BK virus associated hemorrhagic cystitis after allogeneic stem cell transplantation.

INTRODUCTION: BK virus associated hemorrhagic cystitis(BKV-AHC) is a serious complication observed after allogeneic stem cell transplantation and the current therapeutic options are scarce with substantial renal side effects. Although the guidelines recommend intravenous cidofovir application with caution to nephrotoxicity, there are few studies which investigated intravesical administration and reported similar therapeutic results with less renal side effects. METHODS: We administered low dose, daily and consecutive (75 mg/day, for 5 days) intravesical cidofovir to 25 patients with BKV-AHC that developed after (ASCT). RESULTS: The response rate in our cohort was 92% and relapse was not encountered in 84% of the patient population during one year of follow-up. The median BK urine viral load significantly decreased from 260,000,000 IU/mL to 53,000,000 IU/mL after a week of treatment (p = 0.0001). Rise in serum creatinine was observed in 5 patients during treatment and post-treatment nephrotoxicity was seen in only 1 patient. CONCLUSIONS: Daily low dose intravesical cidofovir might be an effective treatment option for BKV-AHC after ASCT with favorable less systemic side effects.

Cidofovir in the Management of Non-Genital Warts: A Review.

INTRODUCTION: Cutaneous warts are one of the most frequent reasons for visits to the dermatologist. While there are many treatment options available and commonly used to treat warts, recurrence of lesions is common and complete clearance is rarely achieved. Cidofovir is an antiviral agent that has activity against various DNA viruses, including HPV, the virus that results in verrucae. OBJECTIVE: We examined the literature on the use of cidofovir in the treatment of non-genital warts to further assess its safety and efficacy.  Methods: A review of the literature using PubMed and Google Scholar databases was conducted to find relevant case reports and studies on the use of cidofovir in the treatment of non-genital warts.  Results: Thirteen case reports, five case series, six retrospective chart reviews, and one clinical study were reviewed and included. There were a total of 603 patients, 46.2% males and 53.7% females. Of 603 patients included in this review, 212 (35.2%) were treated with topical cidofovir for their warts. Clearance was achieved in 55.2%. There was no recurrence of lesions after clearance at two months to three years post-treatment (mean of 15.8 months). Of the 212 patients treated with topical cidofovir, 37 (17.4%) reported local side effects such as erythema, pruritus, and burning.  Discussion/Conclusion: Treatment options for recalcitrant non-genital warts are limited and have varying efficacy. Topical cidofovir may serve as an effective, safe, and affordable alternative for the clearance of recalcitrant non-genital warts, but controlled clinical trials are needed.J Drugs Dermatol. 2023;22(10):1009-1016  doi:10.36849/JDD.7258.