Outcomes of transplant recipients treated with cidofovir for resistant or refractory cytomegalovirus infection

BACKGROUND

Treatment of ganciclovir-resistant (GCV-R)/refractory cytomegalovirus (CMV) infections in blood/marrow transplant (BMT) and solid organ transplant (SOT) recipients remains suboptimal. Cidofovir (CDV), a nucleotide analogue with anti-CMV activity, is nephrotoxic and oculotoxic.

METHODS

We retrospectively evaluated the outcomes of SOT and BMT patients with GCV-R/refractory CMV treated with CDV between 1/1/2008 and 12/31/2017.

DATA COLLECTED

baseline demographics, CMV serostatus, clinical and virologic presentations and outcomes, UL97 and UL54 genotype mutations, drug toxicities, and cause of death. Descriptive statistics were used.

RESULTS

16 patients received CDV for treatment of CMV: six BMT and 10 SOT. Seven (47%) of the patients had high-risk donor/recipient serostatus: six (60%) SOT were D+/R-; one (16.7%) BMT was D-/R+. Median time to CMV DNAemia was 131 days post-transplant (IQR, 37.5-230.3). Proven tissue invasive disease was present in three patients (18.8%). Twelve (75%) had genotype testing; 10 (83.3%) of those had antiviral resistance mutations. While on CDV, six (37.5%) developed nephrotoxicity, and four (25%) developed uveitis (two had both uveitis and nephrotoxicity). Eight (50%) had failure to clear CMV DNAemia despite CDV treatment. Eight (50%) of the patients died; median time to death, after initiation of CDV, was 33.5 days [IQR22-988].

CONCLUSIONS

In the absence of good therapeutic alternatives, CDV is used in GCV-R/refractory CMV infection. However, it is associated with a substantial risk of toxicity and failure to clear CMV DNAemia, highlighting the need for development of newer and less toxic therapies. The high mortality in this group of patients underscores the severity of illness in this population.

Risks and outcomes of adenovirus disease in pediatric hematopoietic stem cell transplant recipients-Comparison of current antiviral treatment options

BACKGROUND

Adenovirus disease (ADVd) is a significant burden in pediatric hematopoietic stem cell transplant (HSCT) recipients. However, current knowledge of risk factors associated with poor clinical outcome and the effectiveness of antiviral therapy are not well understood. This study determined the relationship between transplant characteristics and risk of ADVd and also compared time to resolution of disease between pediatric patients who did and did not receive antiviral therapy.

METHODS

We conducted a retrospective, single-center cohort study of pediatric patients undergoing HSCT at Duke University (2005-2016). Cases of ADVd were defined a priori using a classification tool. Cox proportional hazards (CPH) regression models were used to compare the hazard of ADVd between HSCT recipients differing by type of transplant and type of conditioning regimen. The hazard of time to resolution of ADVd by antiviral therapy (cidofovir, brincidofovir, both, or neither) was compared.

RESULTS

Ninety-three of 830 subjects had ADVd post-HSCT (11.2%). Umbilical cord transplant (UCT) recipients had 2.30 (95% CI 1.57, 6.90, P = .002) higher hazard of developing ADVd compared to non-cord allogeneic transplants, and 6.30 higher (95% CI 2.70, 19.61, P < .001) hazard compared to autologous transplants. Subjects who did not receive antiviral therapy experienced earlier resolution of ADVd compared to subjects who received therapy, even after adjusting for subjects with disseminated disease (HR [95% CI]: 3.75 [1.57, 8.93], P = .003).

CONCLUSIONS

Pediatric UCT recipients are at a higher risk for ADVd. Antiviral therapy was not associated with an earlier resolution of ADVd, even in patients with higher disease burden.

Pharmacokinetic and Efficacy Study of Acyclovir Against Cyprinid Herpesvirus 3 in Cyprinus carpio

Cyprinid Herpesvirus 3 (CyHV-3), more commonly known as Koi Herpesvirus (KHV), is a re-emergent virus causing acute systemic infection with high mortality rates in koi fish (Cyprinus carpio). Survivors from outbreaks can become latent carriers, with viral reactivation under stressful conditions and permissible temperatures. No vaccines or treatments are currently available in the United States. Acyclovir has been shown effective in vitro against KHV. This study aimed to evaluate the cytotoxicity of acyclovir and cidofovir to koi fin (KF1) cells, the efficacy of a single antiviral intracoelomic dose in a koi fingerling cohabitation challenge, and the pharmacokinetics of the effective antiviral. Initially, a lactate dehydrogenase release-based assay revealed no significant acyclovir or cidofovir cytotoxicity to KF1 cells for 24 h at up to 1,500 μM. In laboratory-controlled challenges, KHV associated mortalities occurred 2 weeks post-infection. At this point, fish were treated with an antiviral (10 mg/kg acyclovir or 5 mg/kg cidofovir) or sterile phosphate-buffered solution. Morbidity and mortality were monitored for 30 days. A significant cumulative mortality reduction (p ≤ 0.05), and a 3-day mortality delay were detected in the acyclovir-treated group. Similar viral loads were detected in gills recovered from mortalities throughout the challenge and surviving fish at the end of the challenge regardless of treatment. For pharmacokinetic analysis, blood was collected at various timepoints after acyclovir administration. Liquid chromatography tandem mass spectrometry plasma analysis indicated a 141 μM peak plasma concentration at 0.75 h, a 14 h half-life, and a 0.05/h elimination rate constant. Histopathology of target tissues detected no evidence of acyclovir toxicity. Results suggest that a single 10 mg/kg dose of acyclovir administered intracoelomically to koi fingerlings is safe and reduces cumulative mortality during a KHV mortality event. However, multiple doses are probably required for effective treatment of pet fish.

Treatment protocols for BK virus associated hemorrhagic cystitis after hematopoietic stem cell transplantation

Hematopoietic stem cell transplantation (HSCT) represents a vital curative choice for many disease. However its outcome can be hampered by a variety of transplant associated complications. Hemorrhagic cystitis (HC) considered as one of the major difficulties after HSCT. HC symptoms comprise hematuria, dysuria, burning during urination, urinary frequency, urgency and incontinency, abdominal or suprapubic pain, urinary obstruction, and renal or bladder damage. There are a lot of causes for HC development. BK virus reactivation is one of the major causes of HC after HSCT. There is still no standard and approved treatment protocol for BK virus associated HC (BKV-HC). Treatment of HC is according to the local standard operating procedures, depending on the cause and severity. In this study we will review the current treatments available for this disease. We have divided the therapeutic procedures into 5 categories including conservative therapy, complimentary options, surgical procedures, pharmacological treatments and adoptive cell therapy. We believe that comparing the advantages and disadvantages of different therapies make it easier to choose the best treatment protocol. In addition, we had a greater focus on adoptive cell therapy, because it is a relatively new introduced method and might be a logical alternative to conventional treatments for refractory patients. In total, no definitive recommendation is possible for current available treatments because these procedures have only been utilized sporadically in a limit number of patients. Furthermore, a number of treatment options are only experimental and definitely need more effort.

Comparative Study on the Effect of Cidofovir Treatment for Severe Adenovirus Pneumonia

BACKGROUND

Adenovirus infection can cause severe pneumonia even in immunocompetent adults. However, there is limited data on the benefits of cidofovir treatment in severe adenovirus pneumonia. The objective of this study was to evaluate the association of cidofovir treatment with clinical improvement in immunocompetent adult patients with severe adenovirus pneumonia.

METHODS

We evaluated 22 male patients who admitted to intensive care unit (ICU) with severe adenovirus pneumonia between January 2014 and December 2019. The patients were divided into 2 groups, patients treated with cidofovir or not. Clinical outcomes including time to defervescence and stopping of oxygen supplement, length of stay in ICU and hospital, and the need for mechanical ventilation (MV) and extracorporeal membrane oxygenation (ECMO) were compared between the 2 groups.

RESULTS

Among 22 patients, 13 patients (59%) were treated with cidofovir and 9 (41%) were not. The difference in mean time (95% confidence interval [CI]) to defervescence and stopping of oxygen supplement between cidofovir group and no cidofovir group was 2.1 (-5.7 to 10.0) and 1.0 (-14.9 to 16.8) days, respectively. The difference in mean length of stay (95% CI) in ICU and hospital between the 2 groups was 0.2 (-7.1 to 7.5) and -0.4 (-18.3 to 17.5) days, respectively. The differences in proportion of patients requiring MV and ECMO between the 2 groups was 28.2 (-17.4 to 73.8) % and -10.3 (-52.2 to 31.7) %, respectively.

CONCLUSIONS

The treatment with cidofovir for severe adenovirus pneumonia in immunocompetent patients did not improve clinical outcomes. Further studies with larger samples with prospective design are warranted.

Human Adenovirus 7-Associated Hemophagocytic Lymphohistiocytosis-Like Illness: Clinical and Virological Characteristics in a Cluster of Five Pediatric Cases

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening condition of immune dysregulation. Children often suffer from primary genetic forms of HLH, which can be triggered by infection. Others suffer from secondary HLH as a complication of infection, malignancy, or rheumatologic disease. Identifying the exact cause of HLH is crucial, as definitive treatment for primary disease is hematopoietic stem cell transplant. Adenoviruses have been associated with HLH but molecular epidemiology data are lacking.

METHODS

We describe the clinical and virologic characteristics of 5 children admitted with adenovirus infection during 2018-2019 who developed HLH or HLH-like illness. Detailed virologic studies, including virus isolation and comprehensive molecular typing were performed.

RESULTS

All patients recovered; clinical management varied but included immunomodulating and antiviral therapies. A genetic predisposition for HLH was not identified in any patient. Adenovirus isolates were recovered from 4/5 cases; all were identified as genomic variant 7d. Adenovirus type 7 DNA was detected in the fifth case. Phylogenetic analysis of genome sequences identified two clusters - one related to strains implicated in 2016-2017 outbreaks in Pennsylvania and New Jersey, the other related to a 2009 Chinese strain.

CONCLUSIONS

It can be challenging to determine whether HLH is the result of an infectious pathogen alone or genetic predisposition triggered by an infection. We describe 5 children from the same center presenting with an HLH-like illness after onset of adenovirus type 7 infection. None of the patients were found to have a genetic predisposition to HLH. These findings suggest that adenovirus 7 infection alone can result in HLH.

Treatment of parvovirus B19 viremia to facilitate kidney transplantation in a patient with collapsing glomerulopathy

Collapsing glomerulopathy (CG) is a severe form of glomerulopathy which results in nephrotic syndrome and often ensues in rapid progression to end-stage kidney disease (ESKD). Although most commonly a result of HIV infection, other conditions such as parvovirus B19 (PB19) infection have been associated with CG. We present a case of an 18-year-old male with CG associated with PB19 infection who was heterozygous for APOL1 G1 and G2 genetic variants. In an attempt to treat, he was started on intravenous immunoglobulin (IVIg), however rapidly progressed to ESKD. During workup for a living donor kidney transplant he was found to have persistent low-grade PB19 viremia. Despite having no major immunodeficiency and given subsequent courses of IVIg, viremia continued to persist. In a final attempt to eradicate the PB19 we began treatment with cidofovir, an antiviral agent with in vitro efficacy against PB19. Subsequent to initiation of cidofovir, PB19 viremia slowly cleared after which he received a living unrelated kidney transplant. The patient had an early cellular rejection treated with rabbit antithymocyte globulin after which he recovered kidney function without signs of recurrent CG. Our case report suggests efficacy of IVIg and cidofovir for persistent PB19 infection in ESKD to allow subsequent transplantation, while minimizing the risk of recurrent CG.

Refractory extensive vulvar high-grade squamous intraepithelial lesion in an immunosuppressed transplant patient treated with topical cidofovir: A case report

High-grade squamous intraepithelial lesion of the vulva is a premalignant condition which may be especially resistant to treatments among immunosuppressed patients. We present our experience with the use of topical cidofovir in a refractory case of extensive vulvar high-grade squamous intraepithelial lesion in a 37-year-old transplant patient. Eighteen cycles of cidofovir over a 2-year period led to a sustained significant improvement, mainly of the mucosal lesions and was well tolerated. To our knowledge, we have not seen this therapy described in transplant patients with extensive high-grade squamous intraepithelial lesion.

Intravesicular Cidofovir in the Treatment of BK Virus-Associated Hemorrhagic Cystitis Following Hematopoietic Stem Cell Transplantation

Background: BK virus hemorrhagic cystitis (BKV-HC) is a common complication following hematopoietic stem cell transplant (HSCT); optimal management remains uncertain. Supportive care (bladder irrigation and blood transfusions) and intravenous and intravesicular cidofovir have all been used with varying success. Objective: The purpose of this study was to determine the safety and effectiveness of intravesicular cidofovir for BKV-HC following HSCT. Methods: A retrospective analysis of all HSCT patients with BKV-HC prescribed intravesicular cidofovir from 2012 to 2017. Results: 33 patients were treated for BKV-HC. The median age was 50 years (range 23-73), and 18 (55%) were male. The median HC symptom severity was 2, with a median BK urine viral load pretreatment of 100,000,000 IU/mL. Patients received a median of 2 intravesicular treatments (range 1-7) at a dosage of 5 mg/kg per instillation. In all, 19 (59%) patients demonstrated complete clinical resolution of symptoms; 9 (28%) had a partial response; and 4 (13%) had no change in symptoms. Patients with a high pretreatment BK viral load (>100 million) and high HC grade (2-4) had a lower frequency of complete remission. The main side effect of intravesicular instillation was severe bladder spasms in 4 patients (12%). Conclusion and Relevance: This is the largest study of intravesicular cidofovir treatment of BKV HC reported to date; 88% of patients with BVK-HC achieved clinical improvement of symptoms with minimal side effects. Clinical trials of intravesicular cidofovir could provide further evidence for this treatment for BKV-HC.

Drug-induced Uveitis in HIV Patients with Ocular Opportunistic Infections

Purpose: To describe drug-induced uveitis in immunocompromised patients diagnosed with Human Immunodeficiency Virus (HIV) infection Methods: Narrative Review Results: Systemic and intraocular medications administered for the treatment of acquired immune deficiency syndrome (AIDS)-associated diseases in patients infected with HIV are a well-known cause of uveitis. Conclusions: Cidofovir and rifabutin, among other novel anti-retroviral therapies, are strongly associated with drug-induced uveitis. It is imperative to understand the pathogenesis, clinical findings, and management of HIV patients with uveitis induced by these agents.

Low-dose cidofovir and conversion to mTOR-based immunosuppression in polyomavirus-associated nephropathy

BACKGROUND

Polyomavirus-associated nephropathy (PVAN) remains a relevant complication following kidney transplantation with allograft loss rates of up to 50%. Reduction in overall immunosuppression is a cornerstone of therapy, whereas no specific antiviral regimen has shown conclusive benefit to date. The present case series demonstrates the efficacy of a dual therapeutic approach with low-dose cidofovir and conversion to mTOR-based immunosuppression in PVAN.

METHODS

Patients with biopsy-proven PVAN having received low-dose cidofovir (0.25 mg/kg) according to the Tübingen Cidofovir Protocol and been converted to mTOR-based immunosuppression were analyzed retrospectively.

RESULTS

Twenty-three patients with a median follow-up of 2.24 [IQR 1.55-5.01] years were included in the analysis. Median time to PVAN diagnosis was 268 [IQR 153-869] days after transplantation. Polyomavirus clearance from plasma was achieved in 78% of patients after a median of 118 [IQR 76-293] days. Of the 23 patients, nine patients (39%) lost their allograft function during follow-up, but only three of these (13%) due to PVAN. Fourteen patients (61%) stabilized or improved allograft function. The cidofovir protocol allowed for specific antiviral therapy without adverse nephrotoxicity, even in patients with low allograft function.

CONCLUSIONS

Low-dose cidofovir and conversion to mTOR-based immunosuppression allow for effective virus clearance and preservation of allograft function in a high proportion of patients with PVAN and progressive allograft dysfunction and may prolong allograft survival in these patients.

Epidemiology and Outcomes of Early-Onset and Late-Onset Adenovirus Infections in Kidney Transplant Recipients

Objective

Adenovirus (ADV) infection after kidney transplantation (KT) causes significant morbidity. Patient characteristics and outcomes of ADV infection in KT recipients were investigated.

Method

All adult KT recipients with ADV infection between January 2015 and June 2019 were included. ADV infection/disease was defined as detection of ADV DNA in clinical specimens/plus symptoms. Clinical and laboratory findings, treatments, and outcomes were assessed.

Results

Adenovirus infection was diagnosed in 24 of 751 (3.2%) KT recipients. Twenty (83%) were male with a median age of 47 years (interquartile range [IQR], 36–58). Fifteen (63%) underwent deceased donor KT, and 13 (54%) received induction therapy. Twenty-one (88%) and 4 (17%) patients developed hemorrhagic cystitis and disseminated disease, respectively. There were equal distributions of early-onset (EOI) (≤3 months) and late-onset (LOI) (>3 months) infections. Patients who were diagnosed with EOI had lower median absolute lymphocyte counts compared with those with LOI (735/mm³ [IQR, 543–1123] vs 1122/mm³ [IQR, 784–1344], P = .04). All achieved resolution after reduction of their immunosuppression regimen and 13 (54%) received cidofovir therapy. Eighteen (75%) developed allograft dysfunction, of which 67% were transient. One (4%) underwent nephrectomy for allograft failure and 1 (4%) died (non-ADV–related). Patients with EOI were more likely to receive cidofovir therapy (75% vs 33%, P = .04) and develop other opportunistic infections (75% vs 8%, P < .001).

Conclusions

Adenovirus infection after KT typically involves a genitourinary system and transiently impairs an allograft function. Those who developed early infection tend to have more lymphopenia, coinfection, and receive antiviral therapy.

Neutropenia and renal dysfunction due to intravesical cidofovir for virus-associated hemorrhagic cystitis after kidney and allogenic hematopoietic stem cell transplantations

We present a patient with virus-associated hemorrhagic cystitis who underwent kidney and allogenic hematopoietic stem cell transplantations (allo-HSCT). Six months post-allo-HSCT, adenovirus hemorrhagic cystitis occurred, which has been in remission after a single dose of intravesical cidofovir. This might cause prolonged neutropenia and nephrotoxicity, suggesting cidofovir absorption in the blood.

Safety considerations with current and emerging antiviral therapies for cytomegalovirus infection in transplantation

Introduction: Human cytomegalovirus (HCMV) is a major contributor of morbidity and mortality, and its management is essential for the successful outcome of solid organ and hematopoietic stem cell transplantation. Areas covered: This review discusses the safety profiles of currently available and emerging antiviral drugs and the other strategies for HCMV prevention and treatment after transplantation. Expert opinion: Strategies for management of HCMV rely largely on the use of antiviral agents that inhibit viral DNA polymerase (ganciclovir/valganciclovir, foscarnet, and cidofovir/brincidofovir) and viral terminase complex (letermovir), with different types and degrees of adverse effects. An investigational agent, maribavir, exerts its anti-CMV effect through UL97 inhibition, and its safety profile is under clinical evaluation. In choosing the antiviral medication to use, it is important to consider these safety profiles in addition to overall efficacy. In addition to antiviral drugs, reduction of immunosuppression is often generally needed in the management of HCMV infection, but with a potential risk of allograft rejection or graft-versus-host disease. The use of HCMV-specific or non-specific intravenous immunoglobulins remains debated, while adoptive HCMV-specific T cell therapy remains investigational, and associated with unique set of adverse effects.

Brincidofovir (CMX001) for the Treatment of Severe Adenoviral Pneumonia in Kidney Transplant Recipient

Adenovirus causes significant morbidity and mortality in solid organ and hematological transplant recipients. Treatment of adenovirus infections includes supportive care, reduction of immune suppression, and in patients with severe disease, intravenous cidofovir. Brincidofovir (CMX001) is a lipid conjugate of cidofovir, with good oral bioavailability, no associated nephrotoxicity, and higher intracellular levels of the active drug compared to cidofovir. We describe a case of severe adenoviral pneumonia in an adult renal transplant recipient who was successfully treated with oral brincidofovir after developing renal insufficiency with intravenous cidofovir. Brincidofovir (CMX001) along with other supportive therapy, may offer an efficacious, safe, and well-tolerated treatment for severe adenoviral infections in solid organ transplant recipients.

Advances in the Development of Antiviral Strategies against Parvovirus B19

Parvovirus B19 (B19V) is a human pathogenic virus, responsible for an ample range of clinical manifestations. Infections are usually mild, self-limiting, and controlled by the development of a specific immune response, but in many cases clinical situations can be more complex and require therapy. Presently available treatments are only supportive, symptomatic, or unspecific, such as administration of intravenous immunoglobulins, and often of limited efficacy. The development of antiviral strategies against B19V should be considered of highest relevance for increasing the available options for more specific and effective therapeutic treatments. This field of research has been explored in recent years, registering some achievements as well as interesting future perspectives. In addition to immunoglobulins, some compounds have been shown to possess inhibitory activity against B19V. Hydroxyurea is an antiproliferative drug used in the treatment of sickle-cell disease that also possesses inhibitory activity against B19V. The nucleotide analogues Cidofovir and its lipid conjugate Brincidofovir are broad-range antivirals mostly active against dsDNA viruses, which showed an antiviral activity also against B19V. Newly synthesized coumarin derivatives offer possibilities for the development of molecules with antiviral activity. Identification of some flavonoid molecules, with direct inhibitory activity against the viral non-structural (NS) protein, indicates a possible line of development for direct antiviral agents. Continuing research in the field, leading to better knowledge of the viral lifecycle and a precise understanding of virus–cell interactions, will offer novel opportunities for developing more efficient, targeted antiviral agents, which can be translated into available therapeutic options.

An overview of letermovir: a cytomegalovirus prophylactic option

Introduction: Human cytomegalovirus (HCMV) or human herpesvirus 5 (HHV-5) is a β-herpesvirus that causes widespread infection in nearly all members of the human population worldwide. Its persistence in humans after primary infection in a latent phase as well as a partial non-protective immune response is the basis for repeated re-activation/re-infection episodes occurring both in immunocompetent and immunocompromised subjects. In the latter patient populations, which include hematopoietic stem cell transplant (HSCT) recipients, HCMV reactivation episodes may be particularly severe, leading to both systemic and end-organ diseases. Since the 90s, at least four antiviral drugs targeting the DNA polymerase complex have been developed for the prevention and treatment of HCMV infections in transplant recipients, used as first-line (ganciclovir and valganciclovir) and second-line therapy (foscarnet and cidofovir). However, due to their toxicity and drug-resistance induction, new drugs with different targets were needed. Areas covered: In 2017, a new drug named letermovir (LTV), which targets the HCMV DNA terminase complex, was licensed for prophylaxis of HCMV infections in HSCT recipients. This is the focus of this review. Expert opinion: LTV safety and efficacy are promising. However, long-term adverse events and the emergence of drug-resistant HCMV strains must be investigated in extended clinical trials prior to drawing final conclusions.

Cytomegalovirus in solid organ transplant recipients-Guidelines of the American Society of Transplantation Infectious Diseases Community of Practice

Cytomegalovirus (CMV) is one of the most common opportunistic infections that affect the outcome of solid organ transplantation. This updated guideline from the American Society of Transplantation Infectious Diseases Community of Practice provides evidence-based and expert recommendations for screening, diagnosis, prevention, and treatment of CMV in solid organ transplant recipients. CMV serology to detect immunoglobulin G remains as the standard method for pretransplant screening of donors and transplant candidates. Antiviral prophylaxis and preemptive therapy are the mainstays of CMV prevention. The lack of a widely applicable viral load threshold for diagnosis and preemptive therapy is highlighted, as a result of variability of CMV nucleic acid testing, even in the contemporary era when calibrators are standardized. Valganciclovir and intravenous ganciclovir remain as drugs of choice for CMV management. Strategies for managing drug-resistant CMV infection are presented. There is an increasing use of CMV-specific cell-mediated immune assays to stratify the risk of CMV infection after solid organ transplantation, but their role in optimizing CMV prevention and treatment efforts has yet to be demonstrated. Specific issues related to pediatric transplant recipients are discussed.

The use of intravesical cidofovir for the treatment of adenovirus-associated haemorrhagic cystitis in a kidney transplant recipient

Adenovirus is an important cause of haemorrhagic cystitis in kidney transplant recipients. The optimal treatment for adenovirus-associated haemorrhagic cystitis (AAHC) is unknown. Intravenous cidofovir may be effective, but nephrotoxicity is a major concern. The use of intravesical cidofovir for viral haemorrhagic cystitis has been reported in haematopoietic stem cell transplant recipients and may be associated with a lower risk of nephrotoxicity, but its use has not been reported in kidney transplant recipients. We report the use of intravesical cidofovir for the treatment of AAHC in a kidney transplant recipients, along with a review of the literature.

Outcomes of bevacizumab and cidofovir treatment in HPV-associated recurrent respiratory papillomatosis - review of the literature

OBJECTIVE

Recurrent respiratory papillomatosis (RRP) is caused by human papilloma virus types 6 and 11 and occurs in both children and adults. It is characterized by the proliferation of benign squamous papillomas within the aerodigestive tract. The problem with recurrent respiratory papillomatosis treatment is the high recurrence of papilloma growth after surgical removal.

METHOD

A literature review was carried out through surveys based on electronic data in public domains: MedLine (USA National Library of Medicine), PubMed and SciELO, using the keywords recurrent respiratory papillomatosis, adjuvant treatment, cidofovir, and bevacizumab. All types of papers written in English were included (cross-sectional, prospective and retrospective clinical trials, review papers, and case reports).

RESULTS

In the recent literature, several types of treatment such as surgery with mechanical debulking or laser and adjuvant therapies are mentioned. Intralesional bevacizumab and cidofovir treatment may increase the interval between surgical procedures and decrease the number of procedures per year.

CONCLUSIONS

There is still an ongoing discussion within the European Laryngological Society regarding the balance between effectiveness and side effects of RRP adjuvant treatment, but recent results show promising long-term effects. Bevacizumab and cidofovir in aggressive RRP give hope for improved treatment outcomes.

Airway Papillomatosis: New Treatments for an Old Challenge

Recurrent respiratory papillomatosis (RRP) is the recurrent growth of small, benign tumors, or papillomas, in the respiratory tract, caused by human papillomavirus (HPV). Currently, there is no cure. Palliative treatments seek to prevent airway obstruction, keep underlying tissues healthy, and maintain voice quality. The most common intervention, the local surgical removal of papillomas, may be inadequate as a standalone treatment for pediatric populations that experience rapid papilloma regrowth, as repeated surgeries cause increased damage to the surrounding tissues and impose significant emotional and economic burden on families. Interferon α and Cidofovir have been shown to lengthen the time between surgical interventions and/or decrease the total number of procedures needed, although the evidence of their efficacy and safety is controversial. Novel therapies, including photodynamic therapy, indole-3-carbinol, anti-reflux medication, heat shock protein, and Mumps and HPV vaccination, may provide potential avenues for treatment, but require further research. Among all the novel therapies investigated, systemic bevacizumab seems to offer the most promising alternative to surgery. Randomized control trials to investigate its impact, especially in a pediatric population, should be conducted before implementing it as a standard form of care. This review will summarize the latest literature on medical care for aggressive RRP disease.

Intralesional Cidofovir for Treatment of Acyclovir-Resistant Laryngeal Herpes Manifesting as Supraglottic Mass

INTRODUCTION:

Laryngopharyngeal herpes simplex virus infection is rare and presents typically in the supraglottis. Findings on presentation can range from small mucosal lesions to fungating obstructive masses mimicking neoplasm. Laryngopharyngeal herpes is a medically treated disease.

OBJECTIVES:

Identify potential treatment in cases that are refractory to antiviral medications.

METHODS:

Individual case with treatment adapted from other case report.

CASE PRESENTATION:

We report a case of bulky, obstructive supraglottic and glottic herpes virus laryngitis that presented with dysphonia, dysphagia, and airway complaints resistant to acyclovir analogues that was treated effectively with intralesional cidofovir injection.

CONCLUSIONS:

Our promising initial response suggests a potential novel treatment for this unusual condition.

Adjunctive Use of Cidofovir and Intravenous Immunoglobulin to Treat Invasive Adenoviral Disease in Solid Organ Transplant Recipients

BACKGROUND

Infections with adenoviruses (ADVs) can result in considerable mortality and morbidity in solid organ transplant (SOT) recipients. Standard therapy for ADV infections in transplant recipients is not established. At our institution, intravenous cidofovir and immunoglobulin have been used to treat disseminated or invasive ADV in SOT and hematopoietic stem cell transplant recipients.

METHODS

A retrospective case series of SOT recipients treated with cidofovir and intravenous immunoglobulin was performed.

RESULTS

Five SOT recipients (four renal and one heart transplant) with adenovirus infection were treated successfully with cidofovir and immunoglobulin. Cidofovir was discontinued after the first negative ADV viral load and resolution of clinical symptoms, given the concern for nephrotoxicity in renal transplant recipients. Renal tubular acidosis type 2 and iritis were observed in two patients receiving therapy.

CONCLUSION

Symptom resolution and a single negative ADV viral load may be indicators for cidofovir discontinuation.

Successful treatment of giant condyloma in a pediatric heart transplant recipient with topical cidofovir

We report a case of giant condyloma that developed in a pediatric heart transplant recipient. This infection progressed for several months despite reduction in immunosuppression, topical treatment, and oral cimetidine therapy. Complete resolution was observed following 7 months of topical cidofovir, without evidence of systemic toxicity or rejection.

Comparison of intravenous or intravesical cidofovir in the treatment of BK polyomavirus-associated hemorrhagic cystitis following adult allogeneic stem cell transplantation-A systematic review

INTRODUCTION

BK polyomavirus can lead to hemorrhagic cystitis (BKPyV-HC) in allogeneic stem cell transplantation and therefore to increased morbidity. No causal therapy has been established yet. Cidofovir (CDV) is a nucleotide analog of cytosine that is active against various DNA viruses and it has been described for therapy of BKPyV-HC using 2 admission routes: intravenous and intravesical.

METHODS

We performed a systematic review regarding the comparison of intravenous or intravesical cidofovir in the treatment of BKPyV-HC following adult allogeneic stem cell transplantation. Since there is a lack of randomized controlled trials, we considered all kinds of studies for this review. Due to heterogeneity of the data, we were not able to perform a meta-analysis, so the results are shown descriptively.

RESULTS

The literature search for primary studies yielded 232 results. Finally, 9 studies where considered which included a total of 189 adult patients with BKPyV-HC after allogeneic stem cell transplantation. We could only identify retrospective studies for this review. A total of 172 patients received intravenous CDV, 17 patients received intravesical CDV, and 2 patients received CDV in both admission routes. In 68.0% of the cases, a complete response for intravenous CDV was documented and in 88.2% for intravesical CDV. Interestingly, no kidney toxicity was mentioned in intravesical CDV. 9.3% of the intravenously treated patients had renal failure.

CONCLUSION

There is only weak evidence for the use of CDV. The intravesical admission route should be further investigated because of a good toxicity profile.

Virologic response with 2 different cidofovir dosing regimens for preemptive treatment of adenovirus DNAemia in pediatric solid organ transplant recipients

ADV is frequently seen in our pediatric SOT population. It presents in a variety of clinical presentation and can cause severe disease. In this population, there are very few studies to determine the safety of CDV as a potential therapeutic agent. We present the findings of our retrospective study evaluating the efficacy and safety of CDV as 2 separate dosing regimens. Regimen A uses the standard 5 mg/kg once a week (Regimen A), and the second uses the 1 mg/kg 3 times per week (Regimen B). Overall, the dosing regimen did not differ in nephrotoxicity, but Regimen B had a higher, although non-significant, rate of viral load clearance. This suggests that more frequent dosing at lower levels may be more efficacious without any significant side effects in our SOT population.

Investigation of tumor-tumor interactions in a double human cervical carcinoma xenograft model in nude mice

Tumor-tumor distant interactions within one organism are of major clinical relevance determining clinical outcome. To investigate this poorly understood phenomenon, a double human cervical xenograft model in nude mice was developed. A first tumor was induced subcutaneously by injection of human papillomavirus positive cervical carcinoma cells into the mouse lower right flank and 3 weeks later, animals were challenged with the same tumor cell line injected subcutaneously into the upper left flank. These tumors had no direct physical contact and we found no systemic changes induced by the primary tumor affecting the growth of a secondary tumor. However, ablation of the primary tumor by local treatment with cidofovir, a nucleotide analogue with known antiviral and antiproliferative properties, resulted not only in a local antitumor effect but also in a temporary far-reaching effect leading to retarded growth of the challenged tumor. Cidofovir far-reaching effects were linked to a reduced tumor-driven inflammation, to increased anti-tumor immune responses, and could not be enhanced by co-administration with immune stimulating adjuvants. Our findings point to the potential use of cidofovir in novel therapeutic strategies aiming to kill tumor cells as well as to influence the immune system to fight cancer.

Cidofovir is active against human papillomavirus positive and negative head and neck and cervical tumor cells by causing DNA damage as one of its working mechanisms

Human papillomavirus (HPV) causes cervical cancer and a large fraction of head and neck squamous cell carcinomas (HNSCC). Cidofovir (CDV) proved efficacious in the treatment of several HPV-induced benign and malignant hyper proliferations. To provide a better insight into how CDV selectively eradicates transformed cells, HPV+ and HPV- cervical carcinoma and HNSCC cell lines were compared to normal cells for antiproliferative effects, CDV metabolism, drug incorporation into cellular DNA, and DNA damage. Incorporation of CDV into cellular DNA was higher in tumor cells than in normal cells and correlated with CDV antiproliferative effects, which were independent of HPV status. Increase in phospho-ATM levels was detected following CDV exposure and higher levels of γ-H2AX (a quantitative marker of double-strand breaks) were measured in tumor cells compared to normal cells. A correlation between DNA damage and CDV incorporation into DNA was found but not between DNA damage and CDV antiproliferative effects. These data indicate that CDV antiproliferative effects result from incorporation of the drug into DNA causing DNA damage. However, the anti-tumor effects of CDV cannot be exclusively ascribed to DNA damage. Furthermore, CDV can be considered a promising broad spectrum anti-cancer agent, not restricted to HPV+ lesions.

Treatment of human polyomavirus-7-associated rash and pruritus with topical cidofovir in a lung transplant patient: Case report and literature review

Human polyomavirus-7-associated rash and pruritus (PVARP) is a chronic superficial viral skin infection, which primarily impacts immunocompromised individuals. We report on a case of PVARP in a lung transplant recipient. Our patient developed symptoms 13 years after being on his immunosuppressive regimen, with an insidious course of progressive gray lichenification with marked islands of sparing and quality of life-altering pruritus. Treatment for PVARP is not established; however, topical cidofovir combined with immunomodulation may offer sustained therapeutic benefit.

Renal Toxicity in Pediatric Patients Receiving Cidofovir for the Treatment of Adenovirus Infection

Treatment options for adenovirus infection in immunocompromised children are limited. Nephrotoxicity has been associated with cidofovir use, but the rate of cidofovir-associated nephrotoxicity in pediatric patients is unclear. In a retrospective review of patients with adenovirus infection treated with cidofovir, neonates (n = 5) had higher viral loads and shorter times to renal insufficiency than older children (n = 24). Higher weekly doses of cidofovir were associated with greater increases in creatinine levels. Of 29 courses of cidofovir, 9 were complicated by acute kidney injury; in these children, mortality was high. Cidofovir dosing in children needs to be optimized, and other therapeutic alternatives should be developed.

[18F]-Fluorodeoxyglucose Uptake in Lymphoid Tissue Serves as a Predictor of Disease Outcome in the Nonhuman Primate Model of Monkeypox Virus Infection

Real-time bioimaging of infectious disease processes may aid countermeasure development and lead to an improved understanding of pathogenesis. However, few studies have identified biomarkers for monitoring infections using in vivo imaging. Previously, we demonstrated that positron emission tomography/computed tomography (PET/CT) imaging with [18F]-fluorodeoxyglucose (FDG) can monitor monkeypox disease progression in vivo in nonhuman primates (NHPs). In this study, we investigated [18F]-FDG-PET/CT imaging of immune processes in lymphoid tissues to identify patterns of inflammation in the monkepox NHP model and to determine the value of [18F]-FDG-PET/CT as a biomarker for disease and treatment outcomes. Quantitative analysis of [18F]-FDG-PET/CT images revealed differences between moribund and surviving animals at two sites vital to the immune response to viral infections, bone marrow and lymph nodes (LNs). Moribund NHPs demonstrated increased [18F]-FDG uptake in bone marrow 4 days postinfection compared to surviving NHPs. In surviving, treated NHPs, increase in LN volume correlated with [18F]-FDG uptake and peaked 10 days postinfection, while minimal lymphadenopathy and higher glycolytic activity were observed in moribund NHPs early in infection. Imaging data were supported by standard virology, pathology, and immunology findings. Even with the limited number of subjects, imaging was able to differentiate the difference between disease outcomes, warranting additional studies to demonstrate whether [18F]-FDG-PET/CT can identify other, subtler effects. Visualizing altered metabolic activity at sites involved in the immune response by [18F]-FDG-PET/CT imaging is a powerful tool for identifying key disease-specific time points and locations that are most relevant for pathogenesis and treatment.IMPORTANCE Positron emission tomography and computed tomography (PET/CT) imaging is a universal tool in oncology and neuroscience. The application of this technology to infectious diseases is far less developed. We used PET/CT imaging with [18F]-labeled fluorodeoxyglucose ([18F]-FDG) in monkeys after monkeypox virus exposure to monitor the immune response in lymphoid tissues. In lymph nodes of surviving monkeys, changes in [18F]-FDG uptake positively correlated with enlargement of the lymph nodes and peaked on day 10 postinfection. In contrast, the bone marrow and lymph nodes of nonsurvivors showed increased [18F]-FDG uptake by day 4 postinfection with minimal lymph node enlargement, indicating that elevated cell metabolic activity early after infection is predictive of disease outcome. [18F]-FDG-PET/CT imaging can provide real-time snapshots of metabolic activity changes in response to viral infections and identify key time points and locations most relevant for monitoring the development of pathogenesis and for potential treatment to be effective.

Amino Acid Ester Prodrugs of Nucleoside and Nucleotide Antivirals

OBJECTIVE

The review covers basic principles of the prodrug strategy applied to antiviral nucleoside drugs or drug candidates. Specific role of amino acids as promoieties is explained with respect to transport mechanisms, pharmacokinetics and a low toxicity of compounds. Synthetic approaches to the most important representatives (compounds under clinical investigations or available on the market) are described, including valacyclovir, valganciclovir, valomaciclovir stearate, valcyclopropavir, valtorcitabine, valopicitabine and several attempts to amino acid modifications of antiretroviral nucleosides.

METHOD

A special attention is paid to acyclic nucleoside phosphonates, where the phosphonic acid residue is esterified with a side-chain hydroxyl group of appropriate amino acid (serine, tyrosine) which can be used as single amino acid or as a part of dipeptides further modified on the terminal carboxyl function. The most advantageous pharmacokinetic profile and the best oral bioavailability were found in tyrosinebased prodrugs.

RESULTS & CONCLUSION

Studies were performed successfully on 1-(S)-[3-hydroxy-2-(phosphonomethoxy) propyl]cytosine (cidofovir), 9-(S)-[3-hydroxy-2-(phosphonomethoxy)propyl]adenine and some (R)-2- (phosphonomethoxy)propyl and 2-(phosphonomethoxy)ethyl derivatives including adefovir.

Primary Polyomavirus Infection, Not Reactivation, as the Cause of Trichodysplasia Spinulosa in Immunocompromised Patients

Classic human polyomaviruses (JC and BK viruses) become pathogenic when reactivating from latency. For the rare skin disease trichodysplasia spinulosa, we show that manifestations of the causative polyomavirus (TSPyV) occur during primary infection of the immunosuppressed host. High TSPyV loads in blood and cerebrospinal fluid, sometimes coinciding with cerebral lesions and neuroendocrine symptoms, marked the acute phase of trichodysplasia spinulosa, whereas initiation and maturation of TSPyV seroresponses occurred in the convalescent phase. TSPyV genomes lacked the rearrangements typical for reactivating polyomaviruses. These findings demonstrate the clinical importance of primary infection with this rapidly expanding group of human viruses and explain the rarity of some novel polyomavirus-associated diseases.

Update in the treatment of non-influenza respiratory virus infection in solid organ transplant recipients

INTRODUCTION

Despite the improved outcomes in solid organ transplantation with regard to prevention of rejection and increased patient and graft survival, infection remains a common cause of morbidity and mortality. Respiratory viruses are a frequent and potentially serious cause of infection after solid organ transplantation. Furthermore, clinical manifestations of respiratory virus infection (RVI) may be more severe and unusual in solid organ transplant recipients (SOTRs) compared with the non-immunocompromised population. Areas covered: This article reviews the non-influenza RVIs that are commonly encountered in SOTRs. Epidemiologic and clinical characteristics are highlighted and available treatment options are discussed. Expert opinion: New diagnostic tools, particularly rapid molecular assays, have expanded the ability to identify specific RVI pathogens in SOTRs. This is not only useful from a treatment standpoint but also to guide infection control practices. More data are needed on RVIs in the solid organ transplant population, particularly regarding their effect on rejection and graft dysfunction. There is also a need for new antiviral agents active against these infections as well as markers that can identify which patients would most benefit from treatment.

Topical Formulation of Self-Assembled Antiviral Prodrug Nanomicelles for Targeted Retinal Delivery

Topical drug administration for back of the eye delivery is extremely challenging due to the presence of protection mechanisms and physiological barriers. Self-assembled polymeric nanomicelles have emerged as promising vehicles for drug delivery. Apart from serving as an inert nanocarrier for therapeutic agents, polymeric nanomicelles are known to bypass mononuclear phagocytic system (MPS) and efflux transporters thereby improving drug bioavailability. In this investigation, a highly efficacious biotinylated lipid prodrug of cyclic cidofovir (B-C12-cCDF) was formulated within polymeric nanomicelles as a carrier for targeted retinal delivery. Polymeric nanomicelles were prepared from polyoxyethylene hydrogenated castor oil 40 (HCO-40) and octoxynol 40 (OC-40). In vitro release studies revealed that B-C12-cCDF-loaded nanomicelles released B-C12-cCDF at a faster rate in stimulated tear fluid (STF) in comparison to PBST. MTT and LDH assays demonstrated negligible cytotoxicity of B-C12-cCDF-loaded nanomicelles relative to CDF and B-C12-cCDF in HRPE (human retinal pigment epithelial, D407), HCE-T (human corneal epithelial), and CCL 20.2 (human conjunctival epithelial) cells. Confocal laser scanning microscopy and flow cytometry analyses indicated that B-C12-cCDF-loaded nanomicelles were efficiently internalized into D407 and HCE-T cells in contrast to CDF and B-C12-cCDF. Moreover, little B-C12-cCDF was also observed in the nuclei after 24 h of incubation. Polymeric nanomicelles carrying the transporter targeted prodrug did not produce any cytotoxic effects and were internalized into the cells effectively. Permeability experiments across HCE-T cells further confirmed significant transport of prodrug loaded nanomicelles and their subsequent uptake into D407 cells. These findings indicate that HCO-40/OC-40 based polymeric nanomicelles could become a promising topical delivery system for ocular administration of antiviral agents.

Resistance to the nucleotide analogue cidofovir in HPV(+) cells: a multifactorial process involving UMP/CMP kinase 1

Human papillomavirus (HPV) is responsible for cervical cancer, and its role in head and neck carcinoma has been reported. No drug is approved for the treatment of HPV-related diseases but cidofovir (CDV) exhibits selective antiproliferative activity.

In this study, we analyzed the effects of CDV-resistance (CDV^R) in two HPV(+) (SiHa_CDV and HeLa_CDV) and one HPV(−) (HaCaT_CDV) tumor cell lines. Quantification of CDV metabolites and analysis of the sensitivity profile to chemotherapeutics was performed. Transporters expression related to multidrug-resistance (MRP2, P-gp, BCRP) was also investigated.

Alterations of CDV metabolism in SiHa_CDV and HeLa_CDV, but not in HaCaT_CDV, emerged via impairment of UMP/CMPK1 activity. Mutations (P64T and R134M) as well as down-regulation of UMP/CMPK1 expression were observed in SiHa_CDV and HeLa_CDV, respectively. Altered transporters expression in SiHa_CDV and/or HeLa_CDV, but not in HaCaTCDV, was also noted.

Taken together, these results indicate that CDV^R in HPV(+) tumor cells is a multifactorial process.

Treatment of Adenoviral Acute Respiratory Distress Syndrome Using Cidofovir With Extracorporeal Membrane Oxygenation

Adenovirus infections are associated with respiratory (especially upper respiratory) infection and gastrointestinal disease and occur primarily in infants and children. Although rare in adults, severe lower respiratory adenovirus infections including pneumonia are reported in specific populations, such as military recruits and immunocompromised patients. Antiviral treatment is challenging due to limited clinical experience and lack of well-controlled randomized trials. Several previously reported cases of adenoviral pneumonia showed promising efficacy of cidofovir. However, few reports discussed the efficacy of cidofovir in acute respiratory distress syndrome (ARDS). We experienced 3 cases of adenoviral pneumonia associated with ARDS and treated with cidofovir and respiratory support, including extracorporeal membrane oxygenation (ECMO). All 3 patients showed a positive clinical response to cidofovir and survival at 28 days. Cidofovir with early ECMO therapy may be a therapeutic option in adenoviral ARDS. A literature review identified 15 cases of adenovirus pneumonia associated with ARDS.

BK polyomavirus encephalitis in a patient with thrombotic microangiopathy after an allogeneic hematopoietic stem cell transplant

To date, only one case of BK polyomavirus (BKPyV) encephalitis combined with transplant-associated thrombotic microangiopathy has been reported in an hematopoietic stem cell transplantation (HCT) recipient. We report the case of an HCT recipient who developed thrombotic microangiopathy and subsequent BKPyV encephalitis. She died despite treatment with cidofovir, ciprofloxacin, and intravenous immunoglobulin without improvement in mental status. Early suspicion of BKPyV encephalitis in an HCT recipient presenting with altered mental status and hemorrhagic cystitis is important.

Inhibition of antiviral drug cidofovir on proliferation of human papillomavirus-infected cervical cancer cells

In order to evaluate the potential application value of cidofovir (CDV) in the prevention of human papillomavirus (HPV) infection and treatment of cervical cancer, the inhibitory effect of CDV on the proliferation of HPV 18-positive HeLa cells in cervical cancer was preliminarily investigated, using cisplatin (DDP) as a positive control. An MTT assay was used to analyze the effects of CDV and DDP on HeLa cell proliferation. In addition, clone formation assay and Giemsa staining were used to examine the extent of HeLa cell apoptosis caused by CDV and DDP. Flow cytometry was also used to detect the shape and size of apoptotic cells following propidium iodide staining, while western blot analysis identified the expression levels of of E6 and p53 proteins in HeLa cells. A cell climbing immunofluorescence technique was used to locate the subcellular position of p53 in HeLa cells. The results demonstrated that CDV and DDP inhibited the proliferation of HeLa cells in a concentration- and time-dependent manner. Flow cytometry showed that CDV and DDP treatments resulted in cell arrest in the S-phase, and triggered programmed cell death. Furthermore, western blot analysis revealed that CDV and DDP inhibited E6 protein expression and activated p53 expression in HeLa cells. Finally, the immunofluorescence results indicated that CDV and DDP inhibited the nuclear export of p53 by E6 protein, which is required for degradation of endogenous p53 by MDM2 and human papilloma virus E6. In conclusion, CDV and DDP inhibited HeLa cell proliferation in a concentration- and time-dependent manner, reduced the expression of E6 protein, and reinstated p53 protein activity. Thus, CDV regulates cell cycle arrest and apoptosis, and may be a potential cervical cancer therapeutic strategy.

BK Virus-Associated Hemorrhagic Cystitis After Allogeneic Hematopoietic Stem Cell Transplantation in the Pediatric Population

OBJECTIVE

To study the incidence, risk factors, and treatment of hemorrhagic cystitis secondary to BK-virus reactivation (HC-BKV) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in the pediatric population.

METHODS

Case-control study in which all pediatric patients (0-18 years) who underwent allo-HSCT from September 2009 to January 2014 were followed.

RESULTS

Twenty-nine patients underwent an allo-HSCT. The median age was 9 years (range = 6 months to 15 years), 61% male. The primary diagnosis was acute lymphoblastic leukemia (72.4%). Six (20.7%) developed HC-BKV. In a multivariate analysis of risk factors, it was observed that the reactivation of BK virus was associated with age more than 10 years ( P = .098) and those with positive serology for Epstein-Barr virus ( P = .06). Five of the 6 patients with HC-BKV received cidofovir (CDV) at doses of 3 to 5 mg/kg/week. The treatment lasted a median of 3 cycles (range = 2-5). One of the patients (20%) developed nephrotoxicity. Of the 5 patients treated with CDV, 3 (60%) had a complete response, 1 (20%) partial response, and 1 (20%) no response.

CONCLUSION

We conclude that HC-BKV is a frequent complication after allo-HSCT. CDV therapy can be effective but controlled clinical trials are needed.

Use of cidofovir in pediatric patients with adenovirus infection

Background: Adenoviruses contribute to morbidity and mortality among immunocompromised pediatric patients including stem cell and solid organ transplant recipients. Cidofovir (CDV), an antiviral compound approved by the FDA in 1996, is used for treatment of adenoviral (ADV) infections in immunocompromised patients despite concern of potential nephrotoxicity.   Methods: We conducted a retrospective 5-year review at Boston Children's Hospital of 16 patients (mean age = 6.5 years) receiving 19 courses of CDV. During therapy all pertinent data elements were reviewed to characterize potential response to therapy and incidence of renal dysfunction.   Results: Of the 19 CDV courses prescribed, 16 courses (84%) were in patients who had a positive blood ADV Polymerase chain reaction (PCR) alone or in combination with positive ADV PCR/ Direct Immunofluorescence Assay (DFA) at another site. Respiratory symptoms with or without pneumonia were the most common presentation (10/19, 53%). In the majority of blood positive courses (10/16, 63%), viral clearance was also accompanied by clinical response. This was not the case in four courses where patients expired despite viral clearance, including one in which death was directly attributable to adenovirus. There was reversible renal dysfunction observed during the use of CDV. Conclusions:  CDV appeared safe and reasonably tolerated for treatment of ADV in this pediatric population and was associated with viral response and clinical improvement in the majority of patients but reversible renal dysfunction was a side effect. Further studies of the efficacy of CDV for immunocompromised children with ADV infection are warranted.

Use of cidofovir in pediatric patients with adenovirus infection

Background: Adenoviruses contribute to morbidity and mortality among immunocompromised pediatric patients including stem cell and solid organ transplant recipients. Cidofovir (CDV), an antiviral compound approved by the FDA in 1996, is used for treatment of adenoviral (ADV) infections in immunocompromised patients despite concern of potential nephrotoxicity.   Methods: We conducted a retrospective 5-year review at Boston Children's Hospital of 16 patients (mean age = 6.5 years) receiving 19 courses of CDV. During therapy all pertinent data elements were reviewed to characterize potential response to therapy and incidence of renal dysfunction.   Results: Of the 19 CDV courses prescribed, 16 courses (84%) were in patients who had a positive blood ADV Polymerase chain reaction (PCR) alone or in combination with positive ADV PCR/ Direct Immunofluorescence Assay (DFA) at another site. Respiratory symptoms with or without pneumonia were the most common presentation (10/19, 53%). In the majority of blood positive courses (10/16, 63%), viral clearance was also accompanied by clinical response. This was not the case in four courses where patients expired despite viral clearance, including one in which death was directly attributable to adenovirus. There was reversible renal dysfunction observed during the use of CDV. Conclusions:  CDV appeared safe and reasonably tolerated for treatment of ADV in this pediatric population and was associated with viral response and clinical improvement in the majority of patients but reversible renal dysfunction was a side effect. Further studies of the efficacy of CDV for immunocompromised children with ADV infection are warranted.

Medical and surgical interventions for the treatment of usual-type vulval intraepithelial neoplasia

BACKGROUND

Usual-type vulval intraepithelial neoplasia (uVIN) is a pre-cancerous condition of the vulval skin. Also known as high-grade VIN, VIN 2/3 or high-grade vulval squamous intraepithelial lesion (HSIL), uVIN is associated with high-risk subtype human papilloma virus (HPV) infection. The condition causes distressing vulval symptoms in the majority of affected women and may progress to vulval cancer, therefore is usually actively managed. There is no consensus on the optimal management of uVIN. High morbidity and recurrence rates associated with surgical treatments make less invasive treatments highly desirable.

OBJECTIVES

To determine which interventions are the most effective, safe and tolerable for treating women with uVIN.

SEARCH METHODS

We searched the Cochrane Gynaecological Cancer Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), Issue 8 2015, MEDLINE and EMBASE (up to 1 September 2015). We also searched registers of clinical trials, abstracts of scientific meetings, reference lists of included studies and contacted experts in the field.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that assessed medical and surgical interventions in women with uVIN. If no RCTs were available, we included non-randomised studies (NRSs) with concurrent comparison groups that controlled for baseline case mix in multivariate analysis.

DATA COLLECTION AND ANALYSIS

We used Cochrane methodology with two review authors independently extracting data and assessing risk of bias. Where possible, we synthesised data in meta-analyses using random-effects methods. Network meta-analysis was not possible due to insufficient data.

MAIN RESULTS

We included six RCTs involving 327 women and five NRSs involving 648 women. The condition was variously named by investigators as uVIN, VIN2/3 or high-grade VIN. Five RCTs evaluated medical treatments (imiquimod, cidofovir, indole-3 carbinol), and six studies (one RCT and five NRSs) evaluated surgical treatments or photodynamic therapy. We judged two RCTs and four NRSs to be at a high or unclear risk of bias; we considered the others at relatively low risk of bias. Types of outcome measures reported in NRSs varied and we were unable to pool NRS data. Medical interventions: Topical imiquimod was more effective than placebo in achieving a response (complete or partial) to treatment at five to six months post-randomisation (three RCTs, 104 women; risk ratio (RR) 11.95, 95% confidence interval (CI) 3.21 to 44.51; high-quality evidence). At five to six months, a complete response occurred in 36/62 (58%) and 0/42 (0%) women in the imiquimod and placebo groups, respectively (RR 14.40, 95% CI 2.97 to 69.80). Moderate-quality evidence suggested that the complete response was sustained at one year (one RCT, nine complete responses out of 52 women (38%)) and beyond, particularly in women with smaller VIN lesions. Histologically confirmed complete response rates with imiquimod versus cidofovir at six months were 45% (41/91) and 46% (41/89), respectively (one RCT, 180 women; RR 1.00, 95% CI 0.73 to 1.37; moderate-quality evidence). Twelve-month data from this trial are awaited; however, interim findings suggested that complete responses were sustained at 12 months. Only one trial reported vulval cancer at one year (1/24 and 2/23 in imiquimod and placebo groups, respectively). Adverse events were more common with imiquimod than placebo and dose reductions occurred more frequently in the imiquimod group than in the placebo group (two RCTs, 83 women; RR 7.77, 95% CI 1.61 to 37.36; high-quality evidence). Headache, fatigue and discontinuation were slightly more common with imiquimod than cidofovir (moderate-quality evidence). Quality of life scores reported in one trial (52 women) were not significantly different for imiquimod and placebo. The evidence of effectiveness of topical treatments in immunosuppressed women was scant. There was insufficient evidence on other medical interventions. Surgical and other interventions: Low-quality evidence from the best included NRS indicated, when data were adjusted for confounders, that there was little difference in the risk of VIN recurrence between surgical excision and laser vaporisation. Recurrence occurred in 51% (37/70) of women overall, at a median of 14 months, and was more common in multifocal than unifocal lesions (66% versus 34%). Vulval cancer occurred in 11 women (15.1%) overall at a median of 71.5 months (9 to 259 months). The risk of vulval cancer did not differ significantly between excision and laser vaporisation in any of the NRSs; however, events were too few for robust findings. Alternative surgical procedures that might be as effective include Cavitron ultrasonic surgical aspiration (CUSA) and loop electrosurgical excision (LEEP) procedures, based on low- to very low-quality evidence, respectively. Very low-quality evidence also suggested that photodynamic therapy may be a useful treatment option.We found one ongoing RCT of medical treatment (imiquimod) compared with surgical treatment.

AUTHORS' CONCLUSIONS

Topical treatment (imiquimod or cidofovir) may effectively treat about half of uVIN cases after a 16-week course of treatment, but the evidence on whether this effect is sustained is limited. Factors predicting response to treatment are not clear, but small lesions may be more likely to respond. The relative risk of progression to vulval cancer is uncertain. However, imiquimod and cidofovir appear to be relatively well tolerated and may be favoured by some women over primary surgical treatment.There is currently no evidence on how medical treatment compares with surgical treatment. Women who undergo surgical treatment for uVIN have about a 50% chance of the condition recurring one year later, irrespective of whether treatment is by surgical excision or laser vaporisation. Multifocal uVIN lesions are at a higher risk of recurrence and progression, and pose greater therapeutic dilemmas than unifocal lesions. If occult cancer is suspected despite a biopsy diagnosis of uVIN, surgical excision remains the treatment of choice. If occult cancer is not a concern, treatment needs to be individualised to take into account the site and extent of disease, and a woman's preferences. Combined modalities may hold the key to optimal treatment of this complex disease.

Intravenous Foscarnet With Topical Cidofovir for Chronic Refractory Genital Herpes in a Patient With AIDS

Few case reports have documented the use of topical cidofovir for refractory genital herpes simplex virus (HSV) ulcers in human immunodeficiency virus (HIV) infected patients. This drug formulation lacks a standardized concentration or even a procedural outline as to how it should be compounded. We aim to discuss the utilization of topical cidofovir in addition to presenting a procedural means of compounding it for treatment of refractory genital HSV ulcers. Our patient completed 21 days of intravenous foscarnet and 13 days of topical cidofovir with clinical improvement in the penile and scrotal ulcers. Genital herpes is a concern in patients with HIV because it generally manifests as a persistent infection. Physicians should be aware that when patients fail to respond to the conventional treatment regimens for genital HSV in a timely manner, other options are available, such as topical cidofovir as an adjuvant to systemic antivirals.

Is recurrent respiratory papillomatosis a manageable or curable disease?

OBJECTIVES

Recurrent respiratory papillomatosis (RRP) is a relatively rare disease with potentially devastating consequences for the patient. The purpose of this study was to evaluate the patterns of recurrence of RRP after surgery and determine the effectiveness of combined concurrent adjuvant therapy.

METHODS

A total of 86 patients were diagnosed with and operated on for RRP. The clinical characteristics of 29 of the 86 patients who had undergone operations at other hospitals and who were followed up for >2 years were evaluated retrospectively. A combined concurrent adjuvant therapy was performed with microlaryngeal surgery, 585-nm pulsed dye laser (PDL) application, and an intralesional cidofovir injection. To evaluate the recurrence pattern, the larynx was divided into 10 subsites, and patients were investigated for the frequency of recurrence at the subsites after the operation.

RESULTS

Twenty-nine subjects required a mean of 3.0 operations to achieve complete remission for 2 years. The most common subsites for recurrence were the anterior commissure, subglottis, and epiglottis according to increasing number of operations. The subsites of recurrence tended to be closely correlated with the laryngeal submucosal glandular density distribution. A complete en-bloc layer excision, including the submucosal glands, using cold instruments decreased the recurrence rate of RRP. Applying PDL minimized scarring and provided significant posttreatment voice-quality improvement.

CONCLUSIONS

The results of the recurrent pattern analysis suggest that a combined concurrent adjunctive treatment might be promising as a cure for RRP and restoration of vocal function after treatment.

LEVEL OF EVIDENCE

4. Laryngoscope, 126:1359-1364, 2016.

An overview of early investigational drugs for the treatment of human papilloma virus infection and associated dysplasia

INTRODUCTION

High-risk HPV (HR-HPV) related invasive cervical cancer (ICC) causes >270,000 deaths per annum world-wide with over 85% of these occurring in low-resource countries. Ablative and excisional treatment modalities are restricted for use with high-grade pre-cancerous cervical disease with HPV infection and low-grade dysplasia mostly managed by a watch-and-wait policy.

AREAS COVERED

Various pharmacological approaches have been investigated as non-destructive alternatives for the treatment of HR-HPV infection and associated dysplasia. These are discussed dealing with efficacy, ease-of-use (physician or self-applied), systemic or locally applied, side-effects, cost and risks. The main focus is the perceived impact on current clinical practice of a self-applied, effective and safe pharmacological anti-HPV treatment.

EXPERT OPINION

Current prophylactic HPV vaccines are expensive, HPV type restricted and have little effect in already infected women. Therapeutic vaccines are under development but are also HPV type-restricted. At present, the developed nations use national cytology screening and surgical procedures to treat only women identified with HPV-related high-grade dysplastic disease. However, since HPV testing is rapidly replacing cytology as the test-of-choice, a suitable topically-applied and low-cost antiviral treatment could be an ideal solution for treatment of HPV infection per se with test-of-cure carried out by repeat HPV testing. Cytology would only then be necessary for women who remained HPV positive. Although of significant benefit in the developed countries, combining such a treatment with self-sampled HPV testing could revolutionise the management of this disease in the developing world which lack both the infrastructure and resources to establish national cytology screening programs.

Adenovirus necrotizing hepatitis complicating atypical teratoid rhabdoid tumor

Adenovirus-induced fulminant hepatitis is rare. It has been reported in children with primary immunodeficiency, following transplantation or while receiving chemotherapy for hematological malignancy. We present the case of an infant recovering from chemotherapy for atypical teratoid rhabdoid tumor (ATRT) in whom a diagnosis of hepatic necrosis due to adenovirus was made.

New drug on the horizon for treating adenovirus

Human adenoviruses can cause serious disseminated infections including death in immunosuppressed patients, especially pediatric allogeneic hematopoietic stem cell transplant (allo-HSCT) patients. There are no drugs approved to treat such infections. Cidofovir is used intravenously in many transplant clinics, probably with some effect, but controlled trials have not been completed. Cidofovir is an acyclic nucleoside phosphonate analog of cytidine monophosphate. Following conversion to its diphosphate form within cells, cidofovir is a preferred substrate for the adenovirus DNA polymerase, leading to viral DNA chain termination. Problems with cidofovir include poor cellular uptake and nephrotoxicity. Brincidofovir, a lipid-linked derivative of cidofovir which is active against five families of double-stranded DNA viruses, represents a major advance in anti-adenovirus therapy. It is administered orally, taken up readily by cells followed by release of cidofovir within cells, and is not nephrotoxic. Brincidofovir, under development by Chimerix, Inc., is being evaluated against adenovirus infections in transplant patients including allo-HSCT patients in a phase III clinical trial (AdVise Study). Preliminary results indicate that brincidofovir is safe and very effective at decreasing adenovirus viremia and adenovirus-induced pathogenicity and mortality. Anti-adenovirus adoptive T cell therapy is another very promising approach to treating allo-HSCT patients as demonstrated in clinical studies.