Comprehensive multiomic characterization of human papillomavirus-driven recurrent respiratory papillomatosis reveals distinct molecular subtypes

DNA-based immunotherapy for cancer: In vivo approaches for recalcitrant targets

Immunotherapy has revolutionized cancer treatment and complements traditional therapies, including surgery, chemotherapy, radiation therapy, and targeted therapies. Immunotherapy redirects the patient's immune system against tumors via several immune-mediated approaches. Over the past few years, therapeutic immunization, which enable the patient's T cells to better recognize and kill tumors, have been increasingly tested in the clinic, with several approaches demonstrating treatment improvements. There has been a renewed interest in cancer vaccines due to advances in tumor antigen identification, immune response optimization, novel adjuvants, next-generation vaccine delivery platforms, and antigen designs. The COVID-19 pandemic accelerated progress in nucleic acid-based vaccine manufacturing, which spurred broader interest in mRNA or plasmid platforms. Enhanced DNA vaccine designs, including optimized leader sequences and RNA and codon optimizations, improved formulations, and delivery via adaptive electroporation using stereotactic intramuscular/intradermal methods have improved T cell responses to plasmid-delivered tumor antigens. Additionally, advancements for direct in vivo delivery of DNA-encoded monospecific/bispecific antibodies offer novel tumor-targeting strategies. This review summarizes the recent clinical data for therapeutic cancer vaccines utilizing the DNA platform, including vaccines targeting common tumor-associated and viral antigens and neoantigen vaccines using nucleic acid technologies. We also summarize preclinical data using DNA-launched monoclonal/bispecific antibodies, underscoring their potential as a novel cancer therapy tool.

PRGN-2012 gene therapy in adults with recurrent respiratory papillomatosis: a pivotal phase 1/2 clinical trial

BACKGROUND

Recurrent respiratory papillomatosis (RRP) is a rare debilitating condition caused by chronic infection with human papillomavirus (HPV) type 6 or 11. Papillomas develop in the aerodigestive tract, leading to significant voice disturbance and airway obstruction. No systemic treatment currently exists. We aimed to assess the safety and clinical activity of PRGN-2012 in adult patients with RRP treated at the recommended phase 2 dose.

METHODS

This was a single-centre, single-arm, phase 1/2 trial. Adult patients aged 18 years or older with RRP who required three or more interventions in the 1 year before treatment received adjuvant PRGN-2012 on day 1 following surgical debulking of disease, and on days 15, 43, and 85. Primary outcome measure was complete response rate, defined as the percentage of patients who did not require an intervention to control RRP in the 12 months after treatment. Safety outcomes included treatment-related adverse events. This study is registered ClinicalTrials.gov (NCT04724980).

FINDINGS

From March 16, 2021, to June 1, 2023, 38 patients were enrolled and received the 12-week treatment course. Among the 35 patients treated at the recommended phase 2 dose of 5×1011 particle units, 18 (51%) of 35 patients had a complete response (95% CI 34-69) with the median duration of complete response yet to be reached. Adverse events were mild and included grades 1-2 injection site reaction (34 [97%] of 35), fatigue (28 [80%] of 35), chills (25 [71%] of 35), and fever (24 [69%] of 35).

INTERPRETATION

PRGN-2012 treatment resulted in complete response in 51% of the patients treated and was safe. Based on these positive pivotal study results, a biologics license application to the US Food and Drug Administration (FDA) is planned, positioning PRGN-2012 to be an FDA-approved medical treatment for adult patients with RRP.

FUNDING

National Institutes of Health.

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.

Successful Bevacizumab Therapy in a 25-Year-Old Patient with Recurrent Respiratory Papillomatosis

Background

Recurrent respiratory papillomatosis (RRP) is a chronic condition caused primarily by human papilloma virus (HPV) types 6 and 11, leading to recurrent growths in the respiratory tract. These types of papilloma can cause significant morbidity due to airway obstruction, often requiring frequent surgical interventions. Traditional treatments, including surgical removal and adjunctive therapies like antivirals and immune modulators, often fail to prevent recurrence, impacting the patient's quality of life.

Case description

This report presents a 25-year-old female with a long-standing history of RRP, diagnosed at age 2. Despite numerous interventions, including CO2 laser ablations, interferon therapy, HPV vaccination, and a laryngotomy with tracheal reconstruction, the patient continued to experience severe airway obstruction requiring frequent surgeries. In 2023, intravenous therapy with bevacizumab, vascular endothelial growth factor inhibitor was introduced, leading to a significant reduction in the frequency of surgical interventions from 8 to 4 per year. This reduction improved the patient's respiratory function and quality of life, highlighting bevacizumab's therapeutic potential.

Conclusion

The case underscores the debilitating nature of RRP and the challenges of its management. Bevacizumab, by targeting vascular endothelial growth factor (VEGF), has shown promise in reducing papilloma growth and the need for frequent surgeries. This case supports the inclusion of bevacizumab as an adjunctive therapy in RRP treatment, warranting further research to confirm its long-term efficacy and safety.

LEARNING POINTS

Recurrent respiratory papillomatosis is a rare and complex disease that severely impacts patients' quality of life.This case report demonstrates that bevacizumab can significantly reduce surgical interventions in recurrent respiratory papillomatosis (RRP), offering a promising treatment that improves management of this chronic condition.Bevacizumab, already used in treating various diseases by targeting VEGF, shows promise in managing RRP as well, highlighting its potential across multiple conditions and expanding its therapeutic versatility.

TGF-β neutralization attenuates tumor residency of activated T cells to enhance systemic immunity in mice

A tissue resident-like phenotype in tumor infiltrating T cells can limit systemic anti-tumor immunity. Enhanced systemic anti-tumor immunity is observed in head and neck cancer patients after neoadjuvant PD-L1 immune checkpoint blockade (ICB) and transforming growth factor β (TGF-β) neutralization. Using T cell receptor (TCR) sequencing and functional immunity assays in a syngeneic model of oral cancer, we dissect the relative contribution of these treatments to enhanced systemic immunity. The addition of TGF-β neutralization to ICB resulted in the egress of expanded and exhausted CD8+ tumor infiltrating lymphocytes (TILs) into circulation and greater systemic anti-tumor immunity. This enhanced egress associated with reduced expression of Itgae (CD103) and its upstream regulator Znf683. Circulating CD8+ T cells expressed higher Cxcr3 after treatment, an observation also made in samples from patients treated with dual TGF-β neutralization and ICB. These findings provide the scientific rationale for the use of PD-L1 ICB and TGF-β neutralization in newly diagnosed patients with carcinomas prior to definitive treatment of locoregional disease.

Quantification and Functional Studies of Neutrophilic Cells Identifies Distinct Papilloma Phenotypes

OBJECTIVES

To characterize the distribution of immune cell subsets within laryngeal papillomas and to study the function of potentially immunosuppressive neutrophilic and regulatory T cells (Tregs).

METHODS

Fresh clinical papilloma specimens were collected at the time of surgery and studied with multiparameter flow cytometry. Papilloma infiltrating neutrophilic cells and Tregs were sorted and studied functionally with ex vivo T cell suppression assays.

RESULTS

Flow cytometric analysis of fresh laryngeal papillomas samples from 18 adult patients with recurrent respiratory papillomatosis revealed patterns in immune constituency between patients. Clearly divergent phenotypes based primarily on the degree of neutrophilic and T cell infiltration were identified. Relative neutrophilic cell enrichment and T cell depletion were observed in 50% of samples and neutrophilic cell depletion and T cell enrichment were observed in the others. Greater papilloma neutrophilic cell enrichment was positively associated with the number of clinically indicated interventions required in the 12 months prior to sample collection, linking papilloma neutrophil inflammation to disease severity. Functional assays revealed the ability of both papilloma infiltrating neutrophilic and Tregs to suppress T cell function at roughly equal magnitudes, but substantially increased infiltration of neutrophilic cells compared to Tregs across samples.

CONCLUSION

Neutrophilic cells are an important contributor to immunosuppression within the respiratory papilloma microenvironment. Given these data and the association between greater neutrophilic cell infiltration and lack of clinical response to therapeutic vaccination, additional study of strategies aimed at limiting neutrophilic cell infiltration or function within papillomas is warranted.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:3238-3244, 2024.

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.

The Larynx is Protected from Secondary and Vertical Papillomavirus Infection in Immunocompetent Mice

OBJECTIVE

Mouse papillomavirus MmuPV1 causes both primary and secondary infections of the larynx in immunocompromised mice. Understanding lateral and vertical transmission of papillomavirus to the larynx would benefit patients with recurrent respiratory papillomatosis (RRP). To test the hypothesis that the larynx is uniquely vulnerable to papillomavirus infection, and to further develop a mouse model of RRP, we assessed whether immunocompetent mice were vulnerable to secondary or vertical laryngeal infection with MmuPV1.

METHODS

Larynges were collected from 405 immunocompetent adult mice that were infected with MmuPV1 in the oropharynx, oral cavity, or anus, and 31 mouse pups born to immunocompetent females infected in the cervicovaginal tract. Larynges were analyzed via polymerase chain reaction (PCR) of lavage fluid or whole tissues for viral DNA, histopathology, and/or in situ hybridization for MmuPV1 transcripts.

RESULTS

Despite some positive laryngeal lavage PCR screens, all laryngeal tissue PCR and histopathology results were negative for MmuPV1 DNA, transcripts, and disease. There was no evidence for lateral spread of MmuPV1 to the larynges of immunocompetent mice that were infected in the oral cavity, oropharynx, or anus. Pups born to infected mothers were negative for laryngeal MmuPV1 infection from birth through weaning age.

CONCLUSION

Secondary and vertical laryngeal MmuPV1 infections were not found in immunocompetent mice. Further work is necessary to explore immunologic control of laryngeal papillomavirus infection in a mouse model and to improve preclinical models of RRP.

LEVEL OF EVIDENCE

NA Laryngoscope, 134:2322-2330, 2024.

Pulmonary Involvement in Recurrent Respiratory Papillomatosis: A Systematic Review

Recurrent respiratory papillomatosis (RRP) is a non-malignant disease, characterized by the production of wart-like growths in the respiratory tract, affecting both young people and adults (juvenile-onset recurrent respiratory papillomatosis, JORRP, and adult-onset recurrent respiratory papillomatosis, AORRP, respectively). Infection caused by human papillomavirus (HPV) is known as the main factor involved in RRP development. Complications of RRP may rarely occur, including lung involvement and malignant transformation. The present systematic review aimed to evaluate the prevalence of severe complications, such as lung involvement and lung tumor in JORRP and AORRP patients, and assess the role of HPV genotypes in the progression of disease severity following the guideline for reporting systematic reviews and meta-analysis (PRISMA Statement). A total of 378 studies were found on PubMed and Scopus using the following MESH terms: "recurrent respiratory papillomatosis and lung tumor" and "pulmonary tumor and recurrent respiratory papillomatosis". Basing on inclusion and exclusion criteria, a total of 11 studies were included in the systematic review. We found a pooled prevalence of 8% (95% CI: 4-14%; I2: 87.5%) for lung involvement in RRP patients. In addition, we found a pooled risk difference of 5% in lung involvement between JORRP and AORRP (95% CI: -7-18%; I2: 85.6%, p-value: 0.41). Among patients with lung involvement, we observed a pooled prevalence of lung tumor of 4% (95% CI:1-7%; I2: 67.1%) and a pooled prevalence mortality for this group of 4% (95% CI:2-6%; I2: 0%). Overall, the positivity rate for HPV-6 and -11 in patients with RRP was 91%. Considering only cases with pulmonary involvement, the pooled prevalence for HPV-11 was 21% (95% CI: 5-45%; I2: 77.2%). Our results evidenced a low/middle risk of pulmonary involvement and lung tumor in JORRP and AORRP patients, with an increased risk for HPV-11-positive patients. Further studies should be performed to improve knowledge and adopt preventive measures to contrast the progression to severe diseases in RRP patients.

Preclinical Models of Laryngeal Papillomavirus Infection: A Scoping Review

OBJECTIVE

Laryngeal human papillomavirus (HPV) infection causes recurrent respiratory papillomatosis (RRP) and accounts for up to 25% of laryngeal cancers. Lack of satisfactory preclinical models is one reason that treatments for these diseases are limited. We sought to assess the literature describing preclinical models of laryngeal papillomavirus infection.

DATA SOURCES

PubMed, Web of Science, and Scopus were searched from the inception of database through October 2022.

REVIEW METHODS

Studies searched were screened by two investigators. Eligible studies were peer-reviewed, published in English, presented original data, and described attempted models of laryngeal papillomavirus infection. Data examined included type of papillomavirus, infection model, and results including success rate, disease phenotype, and viral retention.

RESULTS

After screening 440 citations and 138 full-text studies, 77 studies published between 1923 and 2022 were included. Models used low-risk HPV or RRP (n = 51 studies), high-risk HPV or laryngeal cancer (n = 16), both low- and high-risk HPV (n = 1), and animal papillomaviruses (n = 9). For RRP, 2D and 3D cell culture models and xenografts retained disease phenotypes and HPV DNA in the short term. Two laryngeal cancer cell lines were consistently HPV-positive in multiple studies. Animal laryngeal infections with animal papillomaviruses resulted in disease and long-term retention of viral DNA.

CONCLUSIONS

Laryngeal papillomavirus infection models have been researched for 100 years and primarily involve low-risk HPV. Most models lose viral DNA after a short duration. Future work is needed to model persistent and recurrent diseases, consistent with RRP and HPV-positive laryngeal cancer.

LEVEL OF EVIDENCE

NA Laryngoscope, 133:3256-3268, 2023.

Interim Results of a Phase 1/2 Open-Label Study of INO-3107 for HPV-6 and/or HPV-11-Associated Recurrent Respiratory Papillomatosis

OBJECTIVE

To evaluate the safety, immunogenicity, and efficacy of INO-3107, a DNA immunotherapy designed to elicit targeted T-cell responses against human papillomavirus (HPV) types 6 and 11, in adult patients with recurrent respiratory papillomatosis (RRP; NCT04398433).

METHODS

Eligible patients required ≥2 surgical interventions for RRP in the year preceding dosing. INO-3107 was administered by intramuscular (IM) injection followed by electroporation (EP) on weeks 0, 3, 6, and 9. Patients underwent surgical debulking within 14 days prior to first dose, with office laryngoscopy and staging at screening and weeks 6, 11, 26, and 52. Primary endpoint was safety and tolerability, as assessed by treatment-emergent adverse events (TEAEs). Secondary endpoints included frequency of surgical interventions post-INO-3107 and cellular immune responses.

RESULTS

An initial cohort of 21 patients was enrolled between October 2020 and August 2021. Fifteen (71.4%) patients had ≥1 TEAE; 11 (52.4%) were Grade 1, and 3 (14.3%) were Grade 3 (none treatment related). The most frequently reported TEAE was injection site or procedural pain (n = 8; 38.1%). Sixteen (76.2%) patients had fewer surgical interventions in the year following INO-3107 administration, with a median decrease of 3 interventions versus the preceding year. The RRP severity score, modified by Pransky, showed improvement from baseline to week 52. INO-3107 induced durable cellular responses against HPV-6 and HPV-11, with an increase in activated CD4 and CD8 T cells and CD8 cells with lytic potential.

CONCLUSION

The data suggest that INO-3107 administered by IM/EP is tolerable and immunogenic and provides clinical benefit to adults with RRP.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:3087-3093, 2023.

The tumor microenvironment state associates with response to HPV therapeutic vaccination in patients with respiratory papillomatosis

Recurrent respiratory papillomatosis (RRP) is a rare, debilitating neoplastic disorder caused by chronic infection with human papillomavirus (HPV) type 6 or 11 and characterized by growth of papillomas in the upper aerodigestive tract. There is no approved medical therapy, and patients require repeated debulking procedures to maintain voice and airway function. PRGN-2012 is a gorilla adenovirus immune-therapeutic capable of enhancing HPV 6/11-specific T cell immunity. This first-in-human, phase 1 study (NCT04724980) of adjuvant PRGN-2012 treatment in adult patients with severe, aggressive RRP demonstrates the overall safety and clinically meaningful benefit observed with PRGN-2012, with a 50% complete response rate in patients treated at the highest dose. Responders demonstrate greater expansion of peripheral HPV-specific T cells compared with nonresponders. Additional correlative studies identify an association between reduced baseline papilloma HPV gene expression, greater interferon responses and expression of CXCL9 and CXCL10, and greater papilloma T cell infiltration in responders. Conversely, nonresponders were characterized by greater HPV and CXCL8 gene expression, increased neutrophilic cell infiltration, and reduced T cell papilloma infiltration. These results suggest that papilloma HPV gene expression may regulate interferon signaling and chemokine expression profiles within the tumor microenvironment that cooperate to govern clinical response to therapeutic HPV vaccination in patients with respiratory papillomatosis.

[Recurrent laryngeal papillomatosis]

Human papillomaviruses (HPV) 6 and 11 cause 90% of recurrent laryngeal papillomatosis (RLP). It is unclear whether recurrences are caused by new infections or the spread of infected cells. Symptomatic and sometimes curative treatment is laser surgery or conventional microsurgical removal. RLP surgery aims to relieve shortness of breath and improve the voice. Patients (especially children) are affected by voice problems, repetitive surgeries, pulmonary manifestations, and psychological trauma. Vaccination with Gardasil 9 (Merck & Co., Rahway, NJ, USA) prevents new infections with HPV 6, 11, 16, 18, 31, 33, 45, 52, and 58 and induces vaccine antigen-specific antibodies and CD4+ T helper cells. According to current studies, RLP can be avoided with prophylactic vaccination. The treatment is associated with a general vaccination risk (European Medicines Agency approval: girls and boys from 9 years). Studies also show that the vaccine after removal of HPV-associated neoplasia/papilloma prevents recurrences. Extension of the vaccination recommendation to prevent recurrences of HPV-associated diseases in men may promote applicability and herd immunity. For rare and treatment-refractory cases with laryngotracheal involvement, systemic therapy with bevacizumab (e.g. Avastin; Genentech, San Francisco, CA, USA), a VEGF antibody, is a promising adjuvant treatment option.

Expanded Basal Compartment and Disrupted Barrier in Vocal Fold Epithelium Infected with Mouse Papillomavirus MmuPV1

Laryngeal infection with low-risk human papillomaviruses can cause recurrent respiratory papillomatosis (RRP), a disease with severe effects on vocal fold epithelium resulting in impaired voice function and communication. RRP research has been stymied by limited preclinical models. We recently reported a murine model of laryngeal MmuPV1 infection and disease in immunodeficient mice. In the current study, we compare quantitative and qualitative measures of epithelial proliferation, apoptosis, differentiation, and barrier between mice with MmuPV1-induced disease of the larynx and surrounding tissues and equal numbers of uninfected controls. Findings supported our hypothesis that laryngeal MmuPV1 infection recapitulates many features of RRP. Like RRP, MmuPV1 increased proliferation in infected vocal fold epithelium, expanded the basal compartment of cells, decreased differentiated cells, and altered cell–cell junctions and basement membrane. Effects of MmuPV1 on apoptosis were equivocal, as with RRP. Barrier markers resembled human neoplastic disease in severe MmuPV1-induced disease. We conclude that MmuPV1 infection of the mouse larynx provides a useful, if imperfect, preclinical model for RRP that will facilitate further study and treatment development for this intractable and devastating disease.

A Novel In Vivo Model of Laryngeal Papillomavirus-Associated Disease Using Mus musculus Papillomavirus

Recurrent respiratory papillomatosis (RRP), caused by laryngeal infection with low-risk human papillomaviruses, has devastating effects on vocal communication and quality of life. Factors in RRP onset, other than viral presence in the airway, are poorly understood. RRP research has been stalled by limited preclinical models. The only known papillomavirus able to infect laboratory mice, Mus musculus papillomavirus (MmuPV1), induces disease in a variety of tissues. We hypothesized that MmuPV1 could infect the larynx as a foundation for a preclinical model of RRP. We further hypothesized that epithelial injury would enhance the ability of MmuPV1 to cause laryngeal disease, because injury is a potential factor in RRP and promotes MmuPV1 infection in other tissues. In this report, we infected larynges of NOD scid gamma mice with MmuPV1 with and without vocal fold abrasion and measured infection and disease pathogenesis over 12 weeks. Laryngeal disease incidence and severity increased earlier in mice that underwent injury in addition to infection. However, laryngeal disease emerged in all infected mice by week 12, with or without injury. Secondary laryngeal infections and disease arose in nude mice after MmuPV1 skin infections, confirming that experimentally induced injury is dispensable for laryngeal MmuPV1 infection and disease in immunocompromised mice. Unlike RRP, lesions were relatively flat dysplasias and they could progress to cancer. Similar to RRP, MmuPV1 transcript was detected in all laryngeal disease and in clinically normal larynges. MmuPV1 capsid protein was largely absent from the larynx, but productive infection arose in a case of squamous metaplasia at the level of the cricoid cartilage. Similar to RRP, disease spread beyond the larynx to the trachea and bronchi. This first report of laryngeal MmuPV1 infection provides a foundation for a preclinical model of RRP.