Potential risk factors associated with the use of cidofovir to treat benign human papillomavirus-related disease

Current Practice, Safety and Efficacy of Interventions for Recurrent Respiratory Papillomatosis: Evidence From a UK Registry

OBJECTIVES

To determine the current practice, safety and efficacy of interventions used in the management of recurrent respiratory papillomatosis (RRP) in the UK NHS.

DESIGN

Prospective registry (recruitment between 1st April 2018 and 31st August 2022, retrospective data from 1st January 2015 permitted with consent). Sub-group data-linked to Hospital Episode Statistics for additional follow-up (until 31st July 2022).

SETTING

UK NHS hospitals treating RRP patients.

PARTICIPANTS

Children and adults diagnosed with RRP and managed in an NHS hospital.

MAIN OUTCOME MEASURES

Disease severity (Derkay, voice handicap and GRBAS scores), management (type and frequency of surgical and adjuvant intervention) and complications (cancer, death).

RESULTS

Three hundred and thirty patients were entered into the registry; 304 (including 65 children) were eligible for analysis. Children had more severe disease than adults (median Derkay score 10 vs. 5). Microdebrider was the most common surgical intervention, particularly in children (86% of children, 49% of adults). Additionally, lasers (CO2, KTP and pulsed dye) were used in 34% of adults. Gardasil was the most common adjuvant therapy (21 children, 23 adults). Procedural complications were rare (10.8% children, 5.9% adults). Five patients developed laryngeal malignancy; there were six deaths during follow-up period.

CONCLUSIONS

This is the largest UK RRP study to date. RRP is more aggressive in children than adults, and treatment choice differs between age groups. Overall, management was safe with minimal complications reported, and generally effective in maintaining a safe airway. Standardised reporting is required to objectively monitor disease progression and safety over time.

TRIAL REGISTRATION

NCT03465280, ISRCTN36100560.

Evaluating the efficacy and safety of intralesional bevacizumab in the treatment of recurrent respiratory papillomatosis: A systematic review

PURPOSE

Recurrent respiratory papillomatosis (RRP) represents a clinical challenge, often necessitating multiple interventions to help mitigate against disease recurrence or airway obstruction. Multiple management strategies have been advocated by specialists regarding the management of RRP. However, the success rates and disease progression still vary widely. One promising treatment is bevacizumab, a vascular endothelial growth factor (VEGF) monoclonal antibody, which had been initially introduced systemically. More recently, intralesional bevacizumab has become one of the newest arms in dealing with RRP. The aim of this study is to systematically review the literature on the effectiveness, applicability and usage of intralesional bevacizumab in the treatment of RRP.

METHODS

A systematic search was carried out on MEDLINE, Embase, Journals@Ovid and PubMed. PRISMA guidelines were adhered to in the reporting of this study. Study quality and bias risk was assessed using the Newcastle-Ottawa Scale (NOS).

RESULTS

6 studies have met our inclusion and exclusion criteria, one randomised doubled blinded placebo-controlled pilot study, one case series, three prospective and one retrospective study, encompassing a total of 108 patients. Anatomical, functional and objective outcomes are presented and scrutinised. Where reported, complete remission or minimal recurrence was identified in 34/38 (89 %) patients following treatment with intralesional bevacizumab. However, outcome measures were not consistent across all studies making it difficult to draw direct comparisons. Of the 6 studies, 2 (33 %) were deemed poor quality and 4 (66 %) fair quality. No adverse effects of intralesional bevacizumab were reported.

CONCLUSIONS

This study's findings suggest a potential role for intralesional bevacizumab in the management of RRP objectively and functionally. Further research is required to necessitate a stronger evidence base, paying close attention to dose optimisation, assessment of long-term side effects and management of less severe disease phenotypes.

Profiling of VEGF Receptors and Immune Checkpoints in Recurrent Respiratory Papillomatosis

OBJECTIVES

Recurrent respiratory papillomatosis (RRP) is caused by human papilloma virus (HPV) infection of the aerodigestive tract that significantly impacts quality-of-life including the ability to communicate and breathe. Treatment was traditionally limited to serial ablative procedures in the O.R. with possible local adjuvant therapy, but new systemic therapies, such as Vascular endothelial growth factor (VEGF) inhibitors, are showing significant promise. This study aims to determine whether rationale exists for combination therapeutic approaches using VEGF inhibitors and/or immune checkpoint blockade.

METHODS

Using fresh specimens from the O.R., we performed flow cytometry on papilloma, normal adjacent tissue, and blood. Papilloma and surrounding tissue were examined for expression of PD-L1, PD-L2, Galectin-9, VEGFR2, and VEGFR3. CD8+ and CD4+ T cells were assayed for expression of PD-1, TIGIT, LAG3, and TIM3.

RESULTS

Our data shows that papilloma tissue exhibits significantly higher levels of PD-L1 and PD-L2 compared to adjacent tissue. Elevated levels of the VEGF receptor VEGFR3 were also observed in papilloma tissue. When examining T cells within the papilloma, elevated PD-1 and TIGIT expression was observed on CD8+ T cells, while levels of PD-1, TIGIT, and TIM3 were elevated on CD4+ T cells compared to PBMCs. Heterogenous marker expression was observed between individuals.

CONCLUSIONS

Our analysis shows that RRP tissue shows elevated levels of multiple immune check point targets and VEGFR3, with varied patterns unique to each papilloma patient. Some of these immune checkpoint markers already have novel immunotherapies available or in development, providing molecular rationale to offer these systemic treatments to selected patients affected by RRP alongside VEGF inhibitors. Laryngoscope, 134:2819-2825, 2024.

Epigenetic and Genetic Keys to Fight HPV-Related Cancers

Cervical cancer ranks as the fourth most prevalent cancer among women globally, with approximately 600,000 new cases being diagnosed each year. The principal driver of cervical cancer is the human papillomavirus (HPV), where viral oncoproteins E6 and E7 undertake the role of driving its carcinogenic potential. Despite extensive investigative efforts, numerous facets concerning HPV infection, replication, and pathogenesis remain shrouded in uncertainty. The virus operates through a variety of epigenetic mechanisms, and the epigenetic signature of HPV-related tumors is a major bottleneck in our understanding of the disease. Recent investigations have unveiled the capacity of viral oncoproteins to influence epigenetic changes within HPV-related tumors, and conversely, these tumors exert an influence on the surrounding epigenetic landscape. Given the escalating occurrence of HPV-triggered tumors and the deficiency of efficacious treatments, substantial challenges emerge. A promising avenue to address this challenge lies in epigenetic modulators. This review aggregates and dissects potential epigenetic modulators capable of combatting HPV-associated infections and diseases. By delving into these modulators, novel avenues for therapeutic interventions against HPV-linked cancers have come to the fore.

Pharmacotherapy for recurrent respiratory papillomatosis (RRP): a treatment update

Introduction: Recurrent respiratory papillomatosis is a rare human papillomavirus (HPV)-induced condition where warts grow within the airway and especially the larynx to effect voice and restrict breathing.Areas covered: A PubMed search using the following search terms was performed: respiratory papillomatosis and cidofovir, alpha-interferon, bevacizumab, PD1, and HPV vaccines. Surgery remains the mainstay of treatment. There has been a change in options available for adjuvant therapies with systemic bevacizumab and the potential benefits of prophylactic HPV vaccine. Despite efforts to identify a drug therapy to control RRP, no therapy yet remains which is predictable and effective in all. The current status of therapeutic vaccines and immunotherapy is discussed.Expert opinion: The current adjuvant therapies do offer a reasonable expectation of control but the effect for the individual is unpredictable despite the therapies being based on good science. The current therapies would allow an escalating treatment strategy to be formulated, however a single therapy is unlikely to be curative. Multi-center trials are required such that adequate numbers to show an effect are achieved.

Immune therapy for human papillomaviruses-related cancers

Human papillomaviruses (HPVs) are a large family of double strand DNA viruses comprising more than 180 types. Infection with HPV is very common and it is associated with benign and malignant proliferation of skin and squamous mucosae. Many HPVs, considered low-risk such as HPV 6 and 11, produce warts; while high-risk viruses, such as HPVs 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, and 58, induce tumors. About 5% of all cancers in men and women are associated with HPV infection. Because there are not antiviral drugs for HPV infection, current therapies for low-risk HPV infections involve physical removal of the lesion by cryotherapy, trichloracetic acid, laser, or surgical removal. Surgical procedures are effective in the treatment of pre-cancerous lesions, however after these procedures, many recurrences appear due to new re-infections, or to failure of the procedure to eliminate the HPV. In addition, HPV can inhibit recognition of malignant cells by the immune system, leading to the development of cancer lesions. When this occurs, radiotherapy and chemotherapy are then used. Unfortunately, about 50% of the HPV-cancer patients still die. In the past decade, a better knowledge of the natural history of the virus-host interaction and of the immune response against this viral infection has brought new therapeutic strategies geared to modulate the immune system to generate an efficient virus-specific cytotoxic response. Novel HPV protein-expressing vaccines have shown some significant clinical efficacy and systemic HPV-specific cytotoxic T cell responses. This review will describe the current status of the several therapeutic strategies used to treat HPV-induced lesions, and discuss the various new therapies now being tested.

Diagnostic and therapeutic pitfalls in benign vocal fold diseases

More than half of patients presenting with hoarseness show benign vocal fold changes. The clinician should be familiar with the anatomy, physiology and functional aspects of voice disorders and also the modern diagnostic and therapeutic possibilities in order to ensure an optimal and patient specific management. This review article focuses on the diagnostic and therapeutic limitations and difficulties of treatment of benign vocal fold tumors, the management and prevention of scarred vocal folds and the issue of unilateral vocal fold paresis.

Treatment of paediatric laryngeal papillomas: web survey of British Association of Paediatric Otolaryngologists

Background and objective:

Recurrent respiratory papillomatosis is the most common benign neoplasm of the larynx in children. Intralesional injection of cidofovir may have some potential as an adjunctive treatment. There is no standardised protocol in the UK for the management of recurrent respiratory papillomatosis. This study aimed to investigate the management practices of surgeons treating paediatric recurrent respiratory papillomatosis in the UK.

Method:

A web questionnaire survey was sent by e-mail to all members of the British Association of Paediatric Otorhinolaryngology.

Results:

Out of 35 respondents, 23 were at that time treating children with recurrent respiratory papillomatosis. Nineteen respondents preferred to use a microdebrider, 12 preferred laser, and 5 preferred cold steel along with either laser or a microdebrider. Twelve surgeons used cidofovir for selected patients and 12 surgeons did not use cidofovir for any patients. Cidofovir was considered after 0–4 surgical procedures by seven respondents, after 4–6 surgical procedures by four respondents and after 6 surgical procedures by six respondents. Eleven respondents warned patients about the possible side effects of cidofovir and five gave no warning.

Conclusion:

There was no consensus as to when it would be appropriate to use cidofovir, indicating the need for cidofovir usage guidelines.

Voice disorders in children

This article reviews the management of voice disorders in children. We describe the relevant anatomy and development of the larynx throughout childhood, which affects voice. We consider the epidemiologic data to establish the size of the problem. The assessment of the patient in the clinic is described stepwise through the history, examination, laryngoscopy, and extra tests. We then review the common voice disorders encountered and their management, concluding with discussion of future directions, which may herald advances in this field.

Safety of intralesional cidofovir in patients with recurrent respiratory papillomatosis: an international retrospective study on 635 RRP patients

Intralesional use of cidofovir (Vistide(®)) has been one of the mainstays of adjuvant therapy in patients with recurrent respiratory papillomatosis (RRP) since 1998. In 2011, a communication provided by the producer of cidofovir addressed very serious side effects concerning its off-label use. As this was a general warning, it was inconclusive whether this would account for its use in RRP. The aim of this study is to determine whether nephrotoxic, neutropenic, or oncogenic side effects have occurred after intralesional use of cidofovir in patients with RRP. Update of recent developments in RRP, a multicentre questionnaire and a multicentre retrospective chart review. Sixteen hospitals from eleven countries worldwide submitted records of 635 RRP patients, of whom 275 were treated with cidofovir. RRP patients received a median of three intralesional injections (interquartile range 2-6). There were no statistical differences in occurrence of neutropenia or renal dysfunction before and after cidofovir. There was no statistical difference in occurrence of upper airway and tracheal malignancies between the cidofovir and the non-cidofovir group. In this retrospective patient chart review, no clinical evidence was found for more long-term nephrotoxicity, neutropenia or laryngeal malignancies after the administration of intralesional cidofovir in RRP patients.

Therapy of human papillomavirus-related disease

This chapter reviews the current treatment of chronic and neoplastic human papillomavirus (HPV)-associated conditions and the development of novel therapeutic approaches. Surgical excision of HPV-associated lower genital tract neoplasia is very successful but largely depends on secondary prevention programmes for identification of disease. Only high-risk HPV-driven chronic, pre-neoplastic lesions and some very early cancers cannot be successfully treated by surgical procedures alone. Chemoradiation therapy of cervical cancer contributes to the 66-79% cervical cancer survival at 5 years. Outlook for those patients with persistent or recurrent cervical cancer following treatment is very poor. Topical agents such as imiquimod (immune response modifier), cidofovir (inhibition of viral replication; induction apoptosis) or photodynamic therapy (direct damage of tumour and augmentation of anti-tumour immunity) have all shown some useful efficacy (~50-60%) in treatment of high grade vulvar intraepithelial neoplasia (VIN). Provider administered treatments of genital warts include cryotherapy, trichloracetic acid, or surgical removal which has the highest primary clearance rate. Patient applied therapies include podophyllotoxin and imiquimod. Recurrence after "successful" treatment is 30-40%. Further improvements could derive from a rational combination of current therapy with new drugs targeting molecular pathways mediated by HPV in cancer. Small molecule inhibitors targeting the DNA binding activities of HPV E1/E2 or the anti-apoptotic consequences of E6/E7 oncogenes are in preclinical development. Proteasome and histone deacetylase inhibitors, which can enhance apoptosis in HPV positive tumour cells, are being tested in early clinical trials. Chronic high-risk HPV infection/neoplasia is characterised by systemic and/or local immune suppressive regulatory or escape factors. Recently two E6/E7 vaccines have shown some clinical efficacy in high grade VIN patients and this correlated with strong and broad systemic HPV-specific T cell response and modulation of key local immune factors. Treatments that can shift the balance of immune effectors locally in combination with vaccination are now being tested. This article forms part of a special supplement entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine Volume 30, Supplement 5, 2012.

The impact of cidofovir treatment on viral loads in adult recurrent respiratory papillomatosis

Cidofovir is an antiviral agent used in the therapy of recurrent respiratory papillomatosis (RRP). In this study, we hypothesized that cidofovir is effective in decreasing the viral load of human papillomavirus (HPV). We established a type specific real-time PCR and measured HPV DNA loads. The course of viral load of HPV types 6 and 11 after repeated applications of cidofovir intralesionally was compared to the clinical outcome using a modified Derkay score. In 6 of the 8 (75 %) patients, we detected HPV 6. In 2 (25 %) patients, we detected HPV 11. In all of the patients, the viral load and the modified Derkay score decreased significantly during the treatment. We conclude that viral load of HPV can be monitored using the technique described here. Cidofovir in combination with surgical debulking reduces the viral load in patients with RRP. Relapses of the symptoms cannot be avoided but might be delayed.

Genital human papillomavirus infections: current and prospective therapies

Infection with human papillomaviruses (HPVs) is very common and associated with benign and malignant epithelial proliferations of skin and internal squamous mucosae. A subset of the mucosal HPVs are oncogenic and associated with 5 % of all cancers in men and women. There are two licensed prophylactic vaccines, both target HPV 16 and 18, the two most pathogenic, oncogenic types and one, additionally, targets HPV 6 and 11 the cause of genital warts. The approach of deliberate immunization with oncogenic HPV E6 and/or E7 proteins and the generation of antigen-specific cytotoxic T-cells as an immunotherapy for HPV-associated cancer and their high-grade pre-cancers has been tested with a wide array of potential vaccine delivery systems in Phase I/II trials with varying success. Understanding local viral and tumour immune evasion strategies is a prerequisite for the rational design of therapeutic vaccines for HPV-associated infection and disease, progress in this is discussed. There are no antiviral drugs for the treatment of HPV infection and disease. Current therapies are not targeted antiviral therapies, but either attempt physical removal of the lesion or induce inflammation and a bystander immune response. There has been recent progress in the identification and characterization of molecular targets for small molecule antagonists of the HPV proteins E1, E2 and E6 or their interactions with their cellular targets. Lead compounds that could disrupt E1-E2 protein-protein interactions have been discovered as have inhibitors of E6-E6-AP-binding interactions. Some of these compounds showed nanomolar affinities and high specificities and demonstrate the feasibility of this approach for HPV infections. These studies are, however, at an early phase and it is unlikely that any specific anti-HPV chemotherapeutic will be in the clinic within the next 10-20 years.

Next-generation treatment strategies for human papillomavirus-related head and neck squamous cell carcinoma: where do we go?

Oncogenic human papillomavirus (HPV) is currently recognised as a major risk factor for the development of head and neck squamous cell carcinomas (HNSCC). HPV is mostly detected in tumours arising from the oropharynx and more specifically from the tonsil. HPV-related tumours display clinical and molecular characteristics that are distinct from HPV-unrelated tumours, which are generally induced by alcohol and tobacco abuse. Detection of biologically active HPV in HNSCC has prognostic relevance, which warrants the separate classification of HPV-induced tumours and is a prerequisite for further optimisation of treatment protocols for this distinct group. Current guidelines for the treatment of oropharyngeal squamous cell carcinoma (OPSCC) have not incorporated specific treatment modalities for HPV-related tumours. The development of such treatment options is still in a preclinical phase or in early clinical trials. Recent data on treatment response of OPSCC have been obtained by retrospectively analysing HPV-status and indicate that patients with HPV-related tumours show a favourable prognosis, independent of the type of treatment. These patients may benefit from de-intensified treatment, which should be assessed in prospective clinical trials. The development and future use of new antiviral and immunomodulatory therapeutics may be instrumental in this approach to improve survival rates and decrease disease-and-treatment-related morbidity. In this review we will focus on present therapeutic HPV-targeting strategies and discuss future directions for de-intensified treatment of HPV-positive HNSCC.

Effectiveness of cidofovir intralesional treatment in recurrent respiratory papillomatosis

To present the results of recurrent respiratory papillomatosis (RRP) treatment with surgical excision and adjuvant anti-viral cidofovir intralesional use and to examine the correlation between the cidofovir effectiveness and the patient previous history of multiple larynx procedures, age, extension of lesion and dose. 32 patients with laryngeal papillomas were treated with cidofovir in our Department between I.2009 and I.2011. The number of previous RRP debulking procedures ranged from 1 to 100. The intensity of papillomatosis differed from one anatomic site and moderate growth to four or five localizations with heavy extension. The number of injections per patient varied from 1 to 7, and the total volume of 5 mg/ml solution varied from 2 to 33 ml. The injections were combined with laser debulking of the lesions. In disperse papillomata, the injections were administered in particular anatomical sites in 4–6 weeks intervals, in massive lesions injections were repeated in the same anatomical site in 2–4 weeks. Complete remission was observed in 18 out of 32 patients. 13 patients showed remission in a place of cidofovir injection. One patient did not react to the drug. In four patients, new changes in injection places appeared. In two patients, hepatic toxic side effects were observed. Intralesional cidofovir injection has been shown to be an effective and safe therapy for laryngeal papillomatosis and should be considered in those patients who experienced disease relapse.

Novel treatment of atypical human papillomavirus-associated epithelial hyperplasia with cidofovir

PURPOSE

We report a severe case of human papillomavirus-associated epithelial hyperplasia in a man infected with human immunodeficiency virus. These lesions were recalcitrant to treatment with surgical modalities and were eventually controlled with the daily application of a topical cidofovir gel.

PATIENT AND METHODS

A single case is presented, along with a relevant review of the published data.

RESULTS

Before the initiation of cidofovir treatment, the patient had approximately 80% of his gingiva and buccal mucosa engrossed by confluent papillomatous lesions. At 2 weeks after cidofovir treatment, the lesions had markedly regressed, and by 4 weeks, they were almost fully resolved. No untoward adverse reactions occurred.

CONCLUSIONS

Cidofovir formulated as a gel can be safe and effective for the treatment of epithelial hyperplasia in those with human immunodeficiency virus infection.

The HPV16 E6 binding protein Tip-1 interacts with ARHGEF16, which activates Cdc42

Background:

Guanidine exchange factor (GEF)-catalysed activation of Rho proteins such as Cdc42 has been shown to have a crucial role in cellular transformation, malignant progression and invasion. We have previously shown that the HPV16 E6 oncoprotein binds to the PDZ domain protein Tax-interacting-protein 1 (Tip-1) and we now report identification and functional analysis of a novel Tip-1 binding GEF.

Methods:

Yeast two-hybrid, in vitro pull-down, site-directed mutagenesis, semiquantitative PCR, co-immunoprecipitation and western blotting were used to identify/confirm novel Tip-1 binding partners and analyse cellular expression levels. In vitro kinetic analyses of recombinant proteins, siRNA gene silencing and in cell assays were used to measure Rho protein activation.

Results:

Tax-interacting-protein 1 was shown to interact with ARHGEF16 by its carboxyl PDZ binding motif. Levels of ARHGEF16 were increased in transformed and immortalised cells expressing ectopic HPV16 E6 and Cdc42 was co-immunoprecipitated by ARHGEF16 in the presence of high-risk HPV E6. In vitro kinetic analysis confirmed that recombinant ARHGEF16 activates Cdc42 and this was increased by the addition of recombinant Tip-1 and E6. Cells expressing HPV16 E6 had higher levels of Cdc42 activation, which was decreased by siRNA silencing of either Tip-1 or ARHGEF16.

Conclusion:

These data suggest that HPV16 E6, Tip-1 and ARHGEF16 may cooperate to activate Cdc42 and support a potential link between the expression of HPV16 E6 and Cdc42 activation.

Recurrent respiratory papillomatosis: an uncommon but potentially devastating effect of human papillomavirus in children

Human papillomavirus (HPV) causes disease not only in the genital tract, but also in the larynx. Within the larynx HPV 6/11 causes recurrent respiratory papillomatosis (RRP). RRP is relatively uncommon, yet it is devastating for the patient who requires many surgical procedures over years to control it. The cost of HPV-related genital tract disease is thought to be around £31 million per annum, whereas RRP costs in the region of £4 million annually despite RRP being comparatively rare. The HPV vaccination programme has brought great hope, although it is unfortunate that the current UK programme only targets high-risk HPV. Targeting both low- and high-risk HPV would have had additional benefits for the UK.