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.

Stabilization of Recurrent Respiratory Papillomatosis with Pembrolizumab Therapy: A Case Report

Recurrent respiratory papillomatosis (RRP) is a benign neoplastic disease of the respiratory tract that is caused by human papilloma virus (HPV). The current standard of care is surgical excision with adjuvant treatment as needed. Multiple adjuvant treatments have been used with some success, but long-term control of disease remains difficult. We report on a case of a patient with a long history of RRP who had stabilized true vocal fold disease while on pembrolizumab for concurrent early stage lung squamous cell carcinoma.

Surgery and Adjuvant Therapy Improve Derkay Scores in Adult and Pediatric Respiratory Papillomatosis

OBJECTIVES/HYPOTHESIS

Comparing Derkay anatomical score at time of procedure, disease characteristics, and mean treatment interval among adult and pediatric patients with recurrent respiratory papillomatosis (RRP).

STUDY DESIGN

Restrospective study.

METHODS

Retrospective review of juvenile-onset (JO) and adult-onset (AO) RRP patients treated longitudinally at pediatric and adult institutions from 1999 to 2019. Patients were included if they had a tissue diagnosis of papilloma and had at least a 12-month follow-up.

RESULTS

One hundred and twelve patients met inclusion criteria (68 JO-RRP and 44 AO-RRP). All patients were stratified into either potassium titanyl phosphate (KTP) (n = 42), CO₂ (n = 21), or microdebrider (n = 49) treatment groups. The Derkay score improved between first and last procedure in the KTP group (mean difference, 3.5; P < .001), CO₂ group (mean difference, 4.4; P < .001), and microdebrider group (mean difference, 4.1; P < .001), but overall improvement did not differ across groups (P = .73). Baseline mean to last mean Derkay score improved for nine patients during bevacizumab treatments (mean difference, 3.0; P = .01) but did not improve for these same patients during an interval prior to receiving bevacizumab treatments. Baseline mean to last mean Derkay score improved for 19 patients during cidofovir treatments (mean difference, 3.84; P < .001) but did not improve for these same patients during the interval prior to receiving cidofovir treatments. The AO-RRP population had more patients with dysplasia (50%) compared to JO-RRP population (10%) (P < .001).

CONCLUSION

Various surgical modalities appear to be equally effective treatments for RRP. Adult and pediatric patients have decreased recurrent disease burden when receiving bevacizumab or cidofovir. AO-RRP patients have more concomitant dysplasia.

LEVEL OF EVIDENCE

3 Laryngoscope, 132:2420-2426, 2022.

Durable response in a patient with recurrent respiratory papillomatosis treated with immune checkpoint blockade

BACKGROUND

Immune checkpoint blockade can provide clinical benefit for patients with advanced cancer. Here, we report durable disease control over many years following PD-L1 blockade through induction of a viral antigen-specific T cell response in an adult patient with recurrent respiratory papillomatosis.

METHODS

Antigen-specific T cell response assays, single cell RNA-sequencing, and RNA-scope was used to study clinical tissues.

RESULTS

An HPV6 E2-specific T cell clone restricted to HLA-B*55, present at low frequency in the pre-treatment papilloma, significantly expanded after six doses of PD-L1 blockade and remained present and functional at the site of initial response in the larynx as a tissue resident memory T cell for 4 years. An associated reduction in E2 target gene was observed following treatment.

CONCLUSIONS

Although demonstrated in a single exceptional responder, these results highlight that immune checkpoint blockade may induce durable, viral antigen-specific immunity of sufficient magnitude to control disease in patients with nonmalignant disorders.

Laryngotracheal Recurrent Papillomatosis: A Case Study and Survey of Surgical and Systemic Management

This case report presents a 72-year-old man with longstanding recurrent respiratory papillomatosis (RRP). He has undergone multiple procedures for the condition, including an apparent urgent surgical airway followed by tracheoplasty repair. Modern management of complicated RRP should include both local debulking and systemic approaches. Systemic bevacizumab (Avastin) has shown some initial success as an effective treatment option, in addition to other medications such as pembrolizumab. Other future care strategies may include an HPV vaccination and other adjuvants; vaccination has been reported to have the possibility of drastically reducing the incidence of RRP.

Biologics for the Treatment of Recurrent Respiratory Papillomatosis

This article aims to educate readers on adjuvant therapies for recurrent respiratory papillomatosis (RRP). Although antivirals are injected locally into papillomas as an adjuvant treatment, new biologics targeting vascular endothelial growth factor or induction of human papillomavirus (HPV)-specific immunity are gaining traction with demonstration of clinical benefit and mechanism of action in retrospective case series and prospective clinical trials. The future of RRP treatment, alone or in combination with surgery, lies in the careful clinical study of vascular and immune targeting agents that balance the risk of adverse events with the chance for elimination of HPV-infected cells.

How Enhancing Immunity to Low-Risk HPV Could Cure Recurrent Respiratory Papillomatosis

Recurrent respiratory papillomatosis (RRP) is currently treated with repeat surgical resection of papillomatous disease that does not address the fundamental underlying issue of chronic infection with low-risk human papillomavirus. Here, we review the biology and immunology of low-risk human papillomavirus (HPV) infections. Antiviral or antiangiogenic adjuvant treatments similarly address the papillomatous disease itself but do not activate HPV immunity. It is likely that only through immune-mediated clearance of low-risk HPV infection can patients with RRP be cured. In some patients, this occurs spontaneously. In others with more aggressive disease, adjuvant immunotherapy to activate immunity may be needed. Based on current understanding of antiviral immune responses, the only rational strategy to clear HPV-infected epithelial cells is through activation of the T-lymphocyte arm of the adaptive immune response. Translation of immunotherapies that are Food and Drug Administration-approved or under clinical study for cancer, such as immune checkpoint blockade or engineered therapeutic vaccines, may provide a path toward tolerable and efficacious adjuvant immunotherapy for RRP. LEVEL OF EVIDENCE: NA Laryngoscope, 131:2041-2047, 2021.

Immune Therapy Targeting E6/E7 Oncogenes of Human Paillomavirus Type 6 (HPV-6) Reduces or Eliminates the Need for Surgical Intervention in the Treatment of HPV-6 Associated Recurrent Respiratory Papillomatosis

: Background: Recurrent respiratory papillomatosis (RRP) is a rare disorder characterized by the generation of papillomas of the aerodigestive tract, usually associated with human papilloma virus (HPV) subtypes 6, 11. INO-3106 is a DNA plasmid-based immunotherapy targeting E6 and E7 proteins of HPV6, in order to create a robust immune T cell response.

METHODS

Testing of INO-3016 in animal models confirmed immunogenicity of the DNA-based therapy. A single-site open-label Phase 1 study was initiated for patients with HPV6-positive RRP. Patients were dosed with INO-3106 with or without INO-9012, a DNA plasmid immunotherapy that encodes IL-12, delivered intramuscularly (IM) in combination with electroporation (EP) with the CELLECTRA^® device. Patients received an escalating dose of INO-3106, 3 mg once and then 6 mg for three additional doses, each dose three weeks apart, with the third and fourth doses co-administered with INO-9012. The primary objective of the study was to evaluate the safety and tolerability of INO-3106 with and without INO-9012. The secondary objective was to determine cellular immune responses to INO-3106 with and without INO-9012. Exploratory objectives included preliminary clinical efficacy to the therapy.

RESULTS

Three patients were enrolled in this study, of which two had RRP. Study therapy was well-tolerated, with no related serious adverse events and all related adverse events (AEs) were low-grade. Injection site pain was the most common related AE reported. Immunogenicity was evidenced by multiple immune assays showing engagement and expansion of an HPV6-specific cellular response, including cytotoxic T cells. Preliminary efficacy was demonstrated in patients with RRP in the form of reduction in need for surgical intervention for papilloma growth. Prior to intervention, both patients required surgical intervention approximately every 180 days. One patient demonstrated a greater than three-fold increase in surgery avoidance (584 days) and the other patient remains completely surgery-free as of the last contact at 915 days, a greater than 5-fold increase in surgery interval.

CONCLUSION

INO-3106 with and without INO-9012 was well tolerated, immunogenic and demonstrated preliminary efficacy in patients with HPV6-associated RRP aerodigestive lesions. Further clinical study is indicated.