Transnasal photoimmunotherapy with cetuximab sarotalocan sodium: Outcomes on the local recurrence of nasopharyngeal squamous cell carcinoma

Evaluation of real-time pharmacokinetics using fluorescence imaging system in Near-infrared photoimmunotherapy for head and neck cancer

OBJECTIVE

Near-infrared photoimmunotherapy (NIR-PIT) is a molecular targeted therapy that utilizes an antibody-photoabsorber conjugate and excitation light. Herein, excitation of antibody-bound IR700 with near-infrared light at 690 nm causes IR700 to undergo a photochemical ligand reaction. IR700's hydrophilic side chain is released, and the remaining molecules became hydrophobic and lost fluorescence. NIR-PIT targeting the epidermal growth factor receptor using cetuximab sarotalocan sodium, and a laser system has been used to treat patients with unresectable head and neck cancers in Japan since 2021. Light irradiates planned treatment area based on preoperative diagnostic imaging; however, the actual drug accumulation and response status during treatment have not been confirmed. This study aimed to investigate NIR-PIT's fluorescence intensity and antitumor effects on head and neck cancer in humans using real-time fluorescence imaging system.

METHODS

In this single-center prospective observational study, patients with lesions that could be monitored fluorescence were enrolled. Fluorescence intensity during NIR-PIT and tumor characteristics before and after treatment were examined.

RESULTS

Seven patients were included. The fluorescence intensity of the irradiated area showed a rapid decrease in the early stage of treatment, followed by a gradual decrease, almost reaching a plateau before the end of light irradiation. The irradiated areas demonstrated no fluorescence following re-irradiation, and areas irradiated in duplicate tended to lose fluorescence more rapidly than the non-overlapping areas.

CONCLUSION

We observed and measured the drug accumulation and responses during treatment in humans using real-time fluorescence imaging. This information is expected to be applied to evaluate efficacy of NIR-PIT.

The use of 3D computer-aided design to optimize photoimmunotherapy catheter placement

BACKGROUND

There is limited information regarding how technical aspects of Photoimmunotherapy (PIT) catheter placement influences outcomes. We hypothesize that optimized 3D models of PIT treatment will demonstrate a higher volume of tumor treated compared to 3D models of actual intraoperative catheter placement.

METHODS

Clinical and radiographic data were obtained for RM-1929 photoimmunotherapy treated patients at a single institution from March 2016 to August 2021. 3D models were rendered to recreate photoimmunotherapy treatments based on intraoperative images. This was compared to an optimized therapy model for each instance of treatment. Comparisons were made between actual and optimized models based on total volume of tumor treated as well as number of cylindrical diffusers placed per treatment.

RESULTS

3D models were generated for 9 PIT treatments in 6 patients. Optimized PIT models (N = 9) were matched and compared to actual PIT models (N = 9). Volume of tumor treated was higher for the optimized model compared to the actual treatment (22.6 vs 13.9 cm3, p = 0.004) with a higher percentage of total tumor volume treated (92.1 % vs 69.0 %, p = 0.004). Approximately 2.8 additional LF diffusors were placed per treatment in the optimized plan (8.0 vs. 5.2, p = 0.033).

CONCLUSION

In this post-hoc analysis, we demonstrate the importance of appropriate catheter placement in PIT as well as the feasibility of 3D computer aided design to simulate PIT catheter placement. Optimized 3D models demonstrated a higher volume of tumor treated compared to actual catheter placement. 3D computer aided design may be a useful adjunct to preoperative planning to optimize PIT catheter placement.

Near-Infrared Photoimmunotherapy in Brain Tumors-An Unexplored Frontier

Near-infrared photoimmunotherapy (NIR-PIT) is a promising cancer treatment that uses near-infrared light to activate a conjugate of a monoclonal antibody (mAb) and a photoactivatable silica phthalocyanine dye (IRDye700DX: IR700). Unlike conventional photodynamic therapy (PDT), NIR-PIT selectively destroys targeted tumor cells while preserving the surrounding normal tissue and providing superior tissue penetration. Recently, NIR-PIT has been approved for the treatment of unresectable recurrent head and neck cancers in Japan. It induces highly selective cancer cell death; therefore, it is expected to be a new curative treatment option for various cancers, including brain tumors. In this review, we compare the principles of NIR-PIT and PDT and discuss the potential applications of NIR-PIT for brain tumors. We selected targetable proteins across various types of brain tumors and devised a strategy to effectively pass the mAb-IR700 conjugate through the blood-brain barrier (BBB), which is a significant challenge for NIR-PIT in treating brain tumors. Innovative approaches for delivering the mAb-IR700 conjugate across the BBB include exosomes, nanoparticle-based systems, and cell-penetrating peptides. Small-molecule compounds, such as affibodies, are anticipated to rapidly accumulate in tumors within intracranial models, and our preliminary experiments demonstrated rapid uptake. NIR-PIT also induces immunogenic cell death and activates the anti-tumor immune response. Overall, NIR-PIT is a promising approach for treating brain tumors. It has the potential to overcome the limitations of conventional therapies and offers new hope to patients with brain tumors.

Antibody-Drug Conjugates (ADCs): current and future biopharmaceuticals

Antibody-drug conjugates (ADCs) represent a novel class of biopharmaceuticals comprising monoclonal antibodies covalently conjugated to cytotoxic agents via engineered chemical linkers. This combination enables targeted delivery of cytotoxic agents to tumor site through recognizing target antigens by antibody while minimizing off-target effects on healthy tissues. Clinically, ADCs overcome the limitations of traditional chemotherapy, which lacks target specificity, and enhance the therapeutic efficacy of monoclonal antibodies, providing higher efficacy and fewer toxicity anti-tumor biopharmaceuticals. ADCs have ushered in a new era of targeted cancer therapy, with 15 drugs currently approved for clinical use. Additionally, ADCs are being investigated as potential therapeutic candidates for autoimmune diseases, persistent bacterial infections, and other challenging indications. Despite their therapeutic benefits, the development and application of ADCs face significant challenges, including antibody immunogenicity, linker instability, and inadequate control over the release of cytotoxic agent. How can ADCs be designed to be safer and more efficient? What is the future development direction of ADCs? This review provides a comprehensive overview of ADCs, summarizing the structural and functional characteristics of the three core components, antibody, linker, and payload. Furthermore, we systematically assess the advancements and challenges associated with the 15 approved ADCs in cancer therapy, while also exploring the future directions and ongoing challenges. We hope that this work will provide valuable insights into the design and optimization of next-generation ADCs for wider clinical applications.

Photoimmunotherapy for head and neck cancer: A systematic review

Photoimmunotherapy is a new cancer treatment that uses cetuximab sarotalocan sodium, a conjugate of cetuximab and the light activatable dye, IR700, and red light at a wavelength of 690 nm. In Japan, photoimmunotherapy for "unresectable locally advanced or locally recurrent head and neck cancer" has been covered by insurance since 2021. Although presently approved only for head and neck cancer, photoimmunotherapy is an important technology in the future of various cancer treatments. Photoimmunotherapy is an important technology for the future of various cancer treatments, and it is essential to strive for the development and widespread use of photoimmunotherapy in clinical practice. In this review, we will explain the mechanism of photoimmunotherapy, treatment cases, clinical trial data, reports from real world data in Japan, and future issues and prospects as seen in actual clinical practice.

Near Infrared Photoimmunotherapy for Locoregionally Recurrent Oropharyngeal Squamous Cell Carcinoma at Tongue Base After Chemoradiotherapy: A Case Report and Literature Review

Near-infrared photoimmunotherapy (NIR-PIT) is a newly developed treatment. We report a successful case of NIR-PIT for post-irradiation locoregionally recurrent oropharyngeal cancer at the tongue base. A 60-year-old man following primary treatment for oropharyngeal cancer at the tongue base by endoscopy (rT1N0M0). He had been treated by concurrent chemoradiotherapy. NIR-PIT was performed under general anesthesia at the tongue base. Successful therapeutic effects were obtained with no postoperative functional impairment. This case report highlights two important management issues: tracheostomy and pain management after NIR-PIT. NIR-PIT for head and neck cancer will provide a curative treatment option for the locoregional recurrent or unresectable disease following radiotherapy and surgery. It was considered important to ensure sufficient optical tissue penetration range, control pain in the perioperative period, and take measures to prevent edema in the airway.

Evaluation of a Novel Lateral Emitting Laser Fiber for Near-Infrared Photoimmunotherapy

Near-infrared photoimmunotherapy (NIR-PIT) is a new cancer therapy that uses NIR light and conjugates of a tumor-targeting monoclonal antibody and phthalocyanine dye. In clinical practice, frontal and cylindrical diffusers are the only options for NIR illumination. However, illumination in a narrow space is technically difficult with such diffusers. Therefore, we evaluated a lateral illumination system using a lateral emitting laser (LEL) fiber. The LEL fiber illuminated a certain area in a lateral direction. NIR-PIT with an LEL fiber reduced luciferase activity in a light-dose-dependent manner in A431-GFP-luc cells in vitro and significantly suppressed tumor proliferation in a xenograft mouse model. To evaluate the usefulness of the LEL fiber in the illumination of a narrow space, a tumor was illuminated from the inside of a cylinder, mimicking a narrow space, and the fluorescence intensity in the tumor was monitored. In the frontal diffuser, NIR light was unevenly delivered and little light reached a distal tumor area from the illuminated side. By contrast, the LEL fiber allowed a uniform illumination of the entire tumor, and a loss of fluorescence was observed even in distal areas. These findings suggested that the LEL fiber can be used for NIR-PIT and is suitable for NIR light illumination in a narrow space.

Molecular pathways and targeted therapies in head and neck cancers pathogenesis

The substantial heterogeneity exhibited by head and neck cancer (HNC), encompassing diverse cellular origins, anatomical locations, and etiological contributors, combined with the prevalent late-stage diagnosis, poses significant challenges for clinical management. Genomic sequencing endeavors have revealed extensive alterations in key signaling pathways that regulate cellular proliferation and survival. Initiatives to engineer therapies targeting these dysregulated pathways are underway, with several candidate molecules progressing to clinical evaluation phases, including FDA approval for agents like the EGFR-targeting monoclonal antibody cetuximab for K-RAS wild-type, EGFR-mutant HNSCC treatment. Non-coding RNAs (ncRNAs), owing to their enhanced stability in biological fluids and their important roles in intracellular and intercellular signaling within HNC contexts, are now recognized as potent biomarkers for disease management, catalyzing further refined diagnostic and therapeutic strategies, edging closer to the personalized medicine desideratum. Enhanced comprehension of the genomic and immunological landscapes characteristic of HNC is anticipated to facilitate a more rigorous assessment of targeted therapies benefits and limitations, optimize their clinical deployment, and foster innovative advancements in treatment approaches. This review presents an update on the molecular mechanisms and mutational spectrum of HNC driving the oncogenesis of head and neck malignancies and explores their implications for advancing diagnostic methodologies and precision therapeutics.

Lemierre's Syndrome after Head and Neck Photoimmunotherapy for Local Recurrence of Nasopharyngeal Carcinoma

Introduction

Head and neck photoimmunotherapy (HN-PIT) uses a combination of drugs and laser illumination to specifically destroy tumor cells. Lemierre's syndrome is an infectious disease with severe systemic symptoms caused by prior infection in the pharyngeal region, leading to thrombophlebitis. Here, we report a case of Lemierre's syndrome that developed after HN-PIT for recurrent nasopharyngeal carcinoma.

Case Presentation

A 68-year-old male with nasopharyngeal carcinoma (squamous cell carcinoma) underwent HN-PIT after local recurrence with chemoradiation therapy. Three months after HN-PIT, the patient developed fever and neck pain, which led to a diagnosis of Lemierre's syndrome. The patient was treated with antibiotics and anticoagulants for at least 1 month. The patient's general condition and inflammatory findings on blood sampling showed gradual improvement, and a follow-up cervicothoracic computed tomography imaging showed that the venous thrombus had been obscured and the patient was doing well.

Conclusion

HN-PIT is a high-risk procedure for the development of Lemierre's syndrome due to irradiation-induced mucositis, and anticipating the development of Lemierre's syndrome during HN-PIT is important.

Review of RM-1929 Near-Infrared Photoimmunotherapy Clinical Efficacy for Unresectable and/or Recurrent Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell carcinoma (HNSCC) contribute to a significant global cancer burden. Developments in current therapeutic approaches have improved patient outcomes but have limited efficacy in patients with unresectable and/or recurrent HNSCC. RM-1929 near-infrared photoimmunotherapy (NIR-PIT) is an emerging treatment that is currently being investigated in a Phase III clinical trial and has been conditionally approved for the treatment of unresectable and/or recurrent HNSCC in Japan. Here, we collect a series of case reports and clinical trial data to assess the efficacy of RM-1929 NIR-PIT. Disease control rates ranged from 66.7 to 100% across these studies, and overall response rates ranged from 43.3 to 100%, suggesting positive clinical outcomes. Low-grade postoperative localized pain and edema were the most frequently reported side effects, and preliminary reports on quality of life and pain levels suggest that RM-1929 NIR-PIT does not significantly decrease quality of life and is manageable with existing pain management strategies, including opioids. These preliminary data in real-world use of RM-1929 NIR-PIT show that it is a well-tolerated therapy that has clinically meaningful outcomes for patients with unresectable and/or recurrent HNSCC.

A comprehensive overview on antibody-drug conjugates: from the conceptualization to cancer therapy

Antibody-Drug Conjugates (ADCs) represent an innovative class of potent anti-cancer compounds that are widely used in the treatment of hematologic malignancies and solid tumors. Unlike conventional chemotherapeutic drug-based therapies, that are mainly associated with modest specificity and therapeutic benefit, the three key components that form an ADC (a monoclonal antibody bound to a cytotoxic drug via a chemical linker moiety) achieve remarkable improvement in terms of targeted killing of cancer cells and, while sparing healthy tissues, a reduction in systemic side effects caused by off-tumor toxicity. Based on their beneficial mechanism of action, 15 ADCs have been approved to date by the market approval by the Food and Drug Administration (FDA), the European Medicines Agency (EMA) and/or other international governmental agencies for use in clinical oncology, and hundreds are undergoing evaluation in the preclinical and clinical phases. Here, our aim is to provide a comprehensive overview of the key features revolving around ADC therapeutic strategy including their structural and targeting properties, mechanism of action, the role of the tumor microenvironment and review the approved ADCs in clinical oncology, providing discussion regarding their toxicity profile, clinical manifestations and use in novel combination therapies. Finally, we briefly review ADCs in other pathological contexts and provide key information regarding ADC manufacturing and analytical characterization.

Eligibility for Photoimmunotherapy in Patients with Unresectable Advanced or Recurrent Head and Neck Cancer and Changes before and after Systemic Therapy

Photoimmunotherapy is a novel cancer treatment that recently became covered by national health insurance in Japan, but treatment decision-making remains challenging for unresectable advanced or recurrent head and neck cancer. We aimed to clarify the characteristics of patients for whom photoimmunotherapy was indicated by a retrospective chart review. Patients aged ≥20 years diagnosed with advanced or recurrent head and neck cancer who started receiving systemic therapy at the National Cancer Center Hospital East from January 2016 through December 2020 were retrospectively analyzed. Before and after first-line systemic therapy, patients were classified into 3 groups according to eligibility for photoimmunotherapy: eligible, potentially eligible, and ineligible. In total, of 246 patients evaluated-194 after exclusions were analyzed-108 were deemed ineligible for treatment. Of the remaining 86 patients, 8 were considered potentially eligible and 9 eligible. Of the nine eligible patients, four became ineligible after receiving first-line systemic therapy due to disease progression. Our results suggest that the indication of photoimmunotherapy should be considered before, during, and after systemic therapy for unresectable locally advanced or recurrent head and neck cancer.

Near-Infrared Photoimmunotherapy for Oropharyngeal Cancer

Human papillomavirus (HPV)-associated oropharyngeal cancer has a better prognosis than other head and neck cancers. However, rates of recurrence and metastasis are similar and the prognosis of recurrent or metastatic HPV-associated oropharyngeal cancer is poor. Near-infrared photoimmunotherapy (NIR-PIT) is a treatment involving administration of a photosensitizer (IRDye^®700DX) conjugated to a monoclonal antibody followed by activation with near-infrared light illumination. It is a highly tumor-specific therapy with minimal toxicity in normal tissues. Moreover, NIR-PIT is expected to have not only direct effects on a treated lesion but also immune responses on untreated distant lesions. NIR-PIT with cetuximab-IR700 (AlluminoxTM) has been in routine clinical use since January 2021 for unresectable locally advanced or locally recurrent head and neck cancer in patients that have previously undergone radiotherapy in Japan. NIR-PIT for head and neck cancer (HN-PIT) is expected to provide a curative treatment option for the locoregional recurrent or metastatic disease after radiotherapy and surgery. This article reviews the mechanism underlying the effect of NIR-PIT and recent clinical trials of NIR-PIT for head and neck cancers, treatment-specific adverse events, combination treatment with immune checkpoint inhibitors, illumination approach and posttreatment quality of life, and provides a case of series of two patients who receive NIR-PIT for oropharyngeal cancer at our institution.

The Potential of Antibody Technology and Silver Nanoparticles for Enhancing Photodynamic Therapy for Melanoma

Melanoma is highly aggressive and is known to be efficient at resisting drug-induced apoptotic signals. Resection is currently the gold standard for melanoma management, but it only offers local control of the early stage of the disease. Metastatic melanoma is prone to recurrence, and has a poor prognosis and treatment response. Thus, the need for advanced theranostic alternatives is evident. Photodynamic therapy has been increasingly studied for melanoma treatment; however, it relies on passive drug accumulation, leading to off-target effects. Nanoparticles enhance drug biodistribution, uptake and intra-tumoural concentration and can be functionalised with monoclonal antibodies that offer selective biorecognition. Antibody-drug conjugates reduce passive drug accumulation and off-target effects. Nonetheless, one limitation of monoclonal antibodies and antibody-drug conjugates is their lack of versatility, given cancer's heterogeneity. Monoclonal antibodies suffer several additional limitations that make recombinant antibody fragments more desirable. SNAP-tag is a modified version of the human DNA-repair enzyme, O6-alkylguanine-DNA alkyltransferase. It reacts in an autocatalytic and covalent manner with benzylguanine-modified substrates, providing a simple protein labelling system. SNAP-tag can be genetically fused with antibody fragments, creating fusion proteins that can be easily labelled with benzylguanine-modified payloads for site-directed delivery. This review aims to highlight the benefits and limitations of the abovementioned approaches and to outline how their combination could enhance photodynamic therapy for melanoma.