Comparisons of successful and failed Phase III trials of drugs and biologicals tested for mitigation of oral mucositis in patients being treated with radiotherapy with or without concomitant chemotherapy for cancers of the head and neck.

Oral mucositis (OM) remains a significant toxicity among patients being treated with radiotherapy (RT) alone or with concomitant chemotherapy (CRT) for cancers of the head and neck (HNC). Given its clinical significance as an unmet need and its potential commercial viability, the pharmaceutical industry has been actively pursuing an effective intervention. Despite this interest and activity, only a few agents have been studied in Phase III trials (n = 6). The objective of this study was to identify common features that differentiate successful and failed Phase III OM trials. We used the United States Patent and Trademark Office Patent Public Search database to search patents with "oral mucositis" in the claims. We then searched ClinicalTrials.gov and PubMed to determine if Phase III or Phase II trial data for identified biologics/drugs had been published. We assessed each Phase III and Phase II trial for characteristics that may be associated with trial success or failure. We considered a study as a "success" if the primary endpoint reached statistical significance, and we considered a study as "failure" if the primary endpoint did not reach statistical significance. Of the three successful Phase III trials, one investigated avasopasem manganese (Galera Therapeutics) and two examined palifermin (Amgen). The three failed trials included those evaluating dusquetide (Soligenix), iseganan hydrochloride (IntraBiotics Pharmaceuticals), and clonidine (Monopar Therapeutics). We found that differences in the level of sponsor funding, patient inclusion criteria including radiation source and concomitant chemotherapy regimen, and concordance of primary efficacy outcomes between Phase II and Phase III trials influenced outcomes. To properly design clinical trials for OM in HNC patients, it is important that researchers and sponsors take note of specific study characteristics associated with success or failure, particularly with Phase III trials where the risks and costs are the highest.

Comparisons of Non-Oral Immune-Related Adverse Events Among Patients With Cancer With Different Oral Toxicity Profiles.

OBJECTIVES: Immune-related adverse events (irAEs) are common. Oral irAEs tend to cluster in patients who experience concurrent toxicities. We aimed to characterize the frequency and trajectory of non-oral irAEs in patients who developed oral irAEs, assess their relationship with non-oral irAEs, and compare those characteristics with patients without oral irAEs. METHODS: A retrospective chart review was conducted to identify patients who started ICIT between December 11, 2011, and September 15, 2019 (n = 4683) in the Mass General Brigham Registered Patient Data Registry. Demographic information, cancer diagnosis, ICIT regimen, treatment duration, and time and number of infusions to irAE onset were recorded. Non-oral irAEs were categorized into 13 groups. Patients with melanoma, pulmonary cancer, or head and neck cancer who had oral irAEs were then matched with those without oral irAEs to compare the prevalence of concomitant non-oral irAEs. RESULTS: Three hundred and fourteen patients with oral irAEs with a mean age of 65.9 ±â€…12.6 years (43.3% females) were included. Patients with multiple oral irAEs were more likely to have non-oral irAEs (OR: 2.7, 95% CI, 1.3-3.5), including cutaneous (OR: 1.7, 95% CI, 1.1-3.0), rheumatological (OR: 2.2, 95% CI, 1.1-4.2), thyroid (OR: 2.4, 95% CI, 1.2-4.9), and neurological irAEs (OR: 2.5, 95% CI, 1.0-6.3). Compared to matched patients with non-oral irAEs, patients with oral irAEs were more likely to have cutaneous (OR: 1.7, 95% CI, 1.0-2.8) and thyroid (OR: 2.86, 95% CI, 1.1-7.5) irAEs. The development of oral and non-oral irAEs is often coincidental. CONCLUSION: Patients who have non-oral irAEs should be monitored for development of oral irAEs for prompt management.

Monte Carlo based dosimetry of extraoral photobiomodulation for prevention of oral mucositis.

Photobiomodulation therapy (PBMT) is recommended for prevention and treatment of oral mucositis, a painful condition that occurs in cancer patients. Intraoral PBMT is limited to treating distal oral mucosa and oropharynx. Extraoral PBMT may provide a more efficient intervention. The goal of this study was to develop a clinically viable protocol for extraoral PBMT. Monte Carlo modeling was used to predict the distribution of 850 nm light for four treatment sites, using anatomical data obtained from MRI and optical properties from the literature. Simulated incident light power density was limited to 399 mW/cm2 to ensure treatment safety and to prevent tissue temperature increase. The results reveal that total tissue thickness determines fluence rate at the oral mucosa, whereas the thickness of individual tissue layers and melanin content are of minor importance. Due to anatomical differences, the fluence rate varied greatly among patients. Despite these variations, a universal protocol was established using a median treatment time methodology. The determined median treatment times required to deliver efficacious dose between 1 and 6 J/cm2 were within 15 min. The developed PBMT protocol can be further refined using the combination of pretreatment imaging and the Monte Carlo simulation approach implemented in this study.

Avasopasem for the treatment of radiotherapy-induced severe oral mucositis.

INTRODUCTION: Oral mucositis (OM) remains a significant, highly symptomatic, disruptive side effect of radiation and concomitant chemoradiation therapy used for the treatment of squamous cell cancers of the head and neck. Despite its clinical and economic burden, implementation of an effective intervention has been elusive. AREAS COVERED: Increased understanding of the complexity of the biological basis for its pathogenesis has yielded potential druggable targets such as the mitigation of superoxide formation and oxidative stress. Avasopasem manganese is a selective superoxide dismutase mimetic being developed by Galera Therapeutics, which recently submitted a New Drug Application (NDA) to the FDA for a severe OM indication. This review describes the preclinical and clinical studies which led to, and supported the NDA, and assesses the potential utility of avasopasem clinically. EXPERT OPINION: Avasopasem manganese appears to effectively mitigate severe OM associated with concomitant chemoradiation used in the treatment of head and neck cancers, as well as cisplatin-associated renal toxicity in the absence of impairing tumor response.

Application of big data analyses to compare the impact of oral and gastrointestinal mucositis on risks and outcomes of febrile neutropenia and septicemia among patients hospitalized for the treatment of leukemia or multiple myeloma.

PURPOSE: Oral ulcerative mucositis (UM) and gastrointestinal mucositis (GIM) have been associated with increased likelihood of systemic infection (bacteremia and sepsis) in patients being treated for hematological malignancies. To better define and contrast differences between UM and GIM, we utilized the United States 2017 National Inpatient Sample and analyzed patients hospitalized for the treatment of multiple myeloma (MM) or leukemia. METHODS: We utilized generalized linear models to assess the association between adverse events-UM and GIM-among hospitalized MM or leukemia patients and the outcome of febrile neutropenia (FN), septicemia, burden of illness, and mortality. RESULTS: Of 71,780 hospitalized leukemia patients, 1255 had UM and 100 GIM. Of 113,915 MM patients, 1065 manifested UM and 230 had GIM. In an adjusted analysis, UM was significantly associated with increased risk of FN in both the leukemia (aOR = 2.87, 95% CI = 2.09-3.92) and MM cohorts (aOR = 4.96, 95% CI = 3.22-7.66). Contrastingly, UM had no effect on the risk of septicemia in either group. Likewise, GIM significantly increased the odds of FN in both leukemia (aOR = 2.81, 95% CI = 1.35-5.88) and MM (aOR = 3.75, 95% CI = 1.51-9.31) patients. Similar findings were noted when we restricted our analysis to recipients of high-dose condition regimens in preparation for hematopoietic stem-cell transplant. UM and GIM were consistently associated with higher burden of illness in all the cohorts. CONCLUSION: This first use of big data provided an effective platform to assess the risks, outcomes, and cost of care of cancer treatment-related toxicities in patients hospitalized for the management of hematologic malignancies.

Radiotherapy-induced severe oral mucositis: pharmacotherapies in recent and current clinical trials.

INTRODUCTION: Oral mucositis (OM) is among the most common, damaging side effects of head and neck radiation therapy and may interfere with patients' ability to comply with optimal treatment. AREAS COVERED: The increasing unmet clinical need, recent clinical trial successes, and the commercial potential have catalyzed interest in the development of effective intervention for OM. A range of small molecules are under development - some still in the preclinical stage, but others close to NDA submission. This review will focus on those drugs which have recently been assessed in a clinical trial and those which are still under clinical study as a prevention or treatment for radiation-associated OM. EXPERT OPINION: In response to the unmet clinical need, both the biotechnology and pharmacological industries have been actively pursuing an agent to prevent/treat radiation-associated OM. This effort has been catalyzed by the identification of multiple drug targets which contribute to OM's pathogenesis. The lessons learned from the many trials which have previously stumbled have led to standardization of clinical trial design, endpoint efficacy definitions, rater assessment, and data interpretation over the past decade. Consequently, results of recently completed clinical trials provide optimism that effective treatment options should be available in the not-too-distant future.

A New Hypothesis Describing the Pathogenesis of Oral Mucosal Injury Associated with the Mammalian Target of Rapamycin (mTOR) Inhibitors.

It has been 24 years since rapamycin (sirolimus) was approved to mitigate solid organ transplant rejection and 16 years since mTOR (mammalian/mechanistic target of rapamycin) inhibitors reached patients as a cancer therapy. While the clinical benefits of mTOR inhibitors (mTORi) are robust, so too are their toxicities. Among the most common issues is the development of ulcers of the oral mucosa (mTOR-inhibitor associated stomatitis; mIAS). These lesions are distinct from those of other anti-cancer agents, occur with regularity, and impact patient outcomes. mIAS' pathogenesis has been the subject of speculation, and its similar presentation to recurrent aphthous stomatitis (RAS) has led to the hypothesis that it might serve as a surrogate to better understand RAS. Based on a review of the literature, the current manuscript provides a hypothesis regarding the mechanisms by which mTORis uniquely initiate mucosal injury and an explanation for the observation that steroids (also an immunosuppressive) are effective in its treatment through a non-immunologic mechanism. Unexplained unique features of mIAS are discussed in this review in the context of future investigation.

Precision medicine for risk prediction of oral complications of cancer therapy-The example of oral mucositis in patients receiving radiation therapy for cancers of the head and neck.

Oral complications of cancer therapy are common, markedly symptomatic, negatively impact patients' quality of life, and add significantly to the cost of care. Patients' risk of treatment-related toxicities is not uniform; most patients suffer at least one side effect, while others tolerate treatment without any. Understanding those factors which impact risk provides opportunities to customize cancer treatment plans to optimize tumor kill and minimize regimen-related toxicities. Oral mucositis (OM) is an iconic example of a clinically significant and common complication of head and neck radiotherapy. Individuals' OM risk is governed by the cumulative impact of factors related to treatment, the tumor, and the patient. In addition to OM risk prediction, a second opportunity to apply precision medicine will evolve as viable treatment options become available. Patients vary widely in how well or poorly they respond to specific treatments. What works well in one individual, might fail in another. Prospective determination of the likelihood of a patient's response or non-response is based on a range of biological interactions. Coupled with risk determination, the application of precision medicine will allow caregivers, patients, and payers to integrate risk/benefit to optimize the probability that the best treatment is be given to the most appropriate patients.

Two-Year Tumor Outcomes of a Phase 2B, Randomized, Double-Blind Trial of Avasopasem Manganese (GC4419) Versus Placebo to Reduce Severe Oral Mucositis Owing to Concurrent Radiation Therapy and Cisplatin for Head and Neck Cancer.

PURPOSE: Avasopasem manganese (GC4419), an investigational selective dismutase mimetic radioprotector, reduced duration, incidence, and severity of severe oral mucositis (World Health Organization grade 3-4) in a phase 2b, randomized, double-blind trial of patients receiving concurrent cisplatin (cis) and radiation therapy (RT) for head and neck cancer. We report the secondary endpoints of final 1- and 2-year tumor outcomes and exploratory data on trismus and xerostomia. METHODS AND MATERIALS: Patients with locally advanced oral cavity or oropharynx cancer to be treated with definitive or postop cis and RT were randomized to 1 of 3 arms: 30 mg avasopasem, 90 mg avasopasem, or placebo. Pairwise comparisons of Kaplan-Meier estimates (each active arm separately vs placebo) were made for overall survival, progression-free survival, locoregional control, and distant metastasis-free survival. Xerostomia and trismus data were collected at each follow-up visit and analyzed for trends by post-RT timepoint and treatment group. RESULTS: At a median follow-up for the entire cohort of 25.5 months (25th-75th percentile, 24.6-26.2 months; range, 0.2-31.9 months), Kaplan-Meier estimates of 1- and 2-year overall survival, progression-free survival, locoregional control, and distant metastasis-free survival were not statistically different. No trends were apparent in xerostomia or trismus data. CONCLUSIONS: Avasopasem does not lead to statistically different tumor control outcomes when used concurrently with cis and RT for head and neck cancer. There was no detectable effect on trismus or xerostomia.

The broadening scope of oral mucositis and oral ulcerative mucosal toxicities of anticancer therapies.

Oral mucositis (OM) is a common, highly symptomatic complication of cancer therapy that affects patients' function, quality of life, and ability to tolerate treatment. In certain patients with cancer, OM is associated with increased mortality. Research on the management of OM is ongoing. Oral mucosal toxicities are also reported in targeted and immune checkpoint inhibitor therapies. The objective of this article is to present current knowledge about the epidemiology, pathogenesis, assessment, risk prediction, and current and developing intervention strategies for OM and other ulcerative mucosal toxicities caused by both conventional and evolving forms of cancer therapy.

Validation of a Monte Carlo Modelling Based Dosimetry of Extraoral Photobiomodulation.

An in vivo validation study was performed to confirm the accuracy of extraoral photobiomodulation therapy (PBMT) dosimetry determined by modelling. The Monte Carlo technique was utilized to calculate the fluence rate and absorbed power of light delivered through multi-layered tissue. Optical properties used during Monte Carlo simulations were taken from the literature. Morphological data of four study volunteers were acquired using magnetic resonance imaging (MRI) scans. Light emitting diode (LED) coupled to a power meter were utilized to measure transmitted power through each volunteer's cheek, in vivo. The transmitted power determined by Monte Carlo modelling was compared to the in vivo measurements to determine the accuracy of the simulations. Experimental and simulation results were in good agreement for all four subjects. The difference between the mean values of the measured transmission was within 12% from the respective transmission obtained using Monte Carlo simulations. The results of the study indicate that Monte Carlo modelling is a robust and reliable method for light dosimetry.

Superoxide Dismutase as an Intervention for Radiation Therapy-Associated Toxicities: Review and Profile of Avasopasem Manganese as a Treatment Option for Radiation-Induced Mucositis.

Toxicities associated with radiation therapy are common, symptomatically devastating, and costly. The best chance to effectively mitigate radiation-associated normal tissue side effects are interventions aimed at disrupting the biological cascade, which is the basis for toxicity development, while simultaneously not reducing the beneficial impact of radiation on tumor. Oxidative stress is a key initiator of radiation-associated normal tissue injury as physiologic antioxidant mechanisms are overwhelmed by the accumulation of effects produced by fractionated treatment regimens. And fundamental to this is the generation of superoxide, which is normally removed by superoxide dismutases (SODs). Attempts to supplement the activity of endogenous SOD to prevent radiation-induced normal tissue injury have included the administration of bovine-derived SOD and increasing SOD production using gene transfer, neither of which has resulted in a clinically acceptable therapy. A third approach has been to develop synthetic small molecule dismutase mimetics. This approach has led to the creation and development of avasopasem manganese, a unique and specific dismutase mimetic that, in clinical trials, has shown promising potential to reduce the incidence, severity and duration of severe oral mucositis amongst patients being treated with concomitant chemoradiation for cancers of the head and neck. Further, avasopasem and related analogues have demonstrated mechanism-related antitumor synergy in combination with high dose per fraction radiotherapy, an observation that is also being tested in clinical trials. An ongoing Phase 3 trial seeks to confirm avasopasem manganese as an effective intervention for severe oral mucositis associated with chemoradiation in head and neck cancer patients.

GM-1111 reduces radiation-induced oral mucositis in mice by targeting pattern recognition receptor-mediated inflammatory signaling.

PURPOSE: Oral mucositis (OM) is a common, painful side effect of radiation therapy used for the treatment of head and neck cancer (HNC). Activation of the innate immune system upon irradiation has been identified as a key precipitating event of OM. To better understand OM's pathogenesis, we studied pattern recognition receptors (PRRs) and their downstream pro-inflammatory cytokines in a mouse model of radiation-induced OM. We also tested therapeutic efficacy of GM-1111 that targets innate immune system to reduce radiation-induced OM. METHODS AND MATERIALS: The pathogenesis of OM was studied in a single X-ray induced mouse model. The severity of OM was measured by visual and microscopical examinations. The irradiation-induced changes of PRRs and their downstream effector cytokine gene expression levels were determined. The efficacy of GM-1111 to reduce OM was tested in single and fractionated irradiation mouse models. The impact of the drug on tumor response to radiation therapy was also tested in a mouse model of human HNC. RESULTS: Radiation-induced tissue ulcerations were radiation-dosage and -time dependent. The lesions showed selective increases in PRR and pro-inflammatory cytokine gene expression levels. Once daily administration of GM-1111 (≥30 mg/kg, s.c.) significantly reduced the severity and the incidence of OM. The drug had little effect on PRRs but significantly inhibited downstream pro-inflammatory cytokine genes. GM-1111 did not interfere radiation therapy to induce HNC SCC-25 tumor regression. Instead, we observed significant drug-induced tumor regression. CONCLUSIONS: Radiation induces tissue damages. The increased expression levels of PRRs and their downstream pro-inflammatory cytokine genes in the damaged tissues suggest their important contribution to the pathogenesis of OM. Drug GM-1111 that targets these innate immune molecules may be a potential drug candidate as an intervention for OM.

A hypothesis for the pathogenesis of radiation-induced oral mucositis: when biological challenges exceed physiologic protective mechanisms. Implications for pharmacological prevention and treatment.

Oral mucositis (OM) remains a significant unmet need for patients being treated with standard concomitant chemoradiation (CRT) regimens for head and neck cancers (HNC). OM's pathogenesis is complex and includes both direct and indirect damage pathways. In this paper, the field is reviewed with emphasis on the initiating and sustaining role of oxidative stress on OM's pathobiology. A hypothesis is presented which suggests that based on OM's clinical and biological trajectory, mucosal damage is largely the consequence of cumulative CRT-induced biological changes overwhelming physiologic self-protective mechanisms. Furthermore, an individual's ability to mount and maintain a protective response is dependent on interacting pathways which are primarily determined by a multiplex consisting of genomics, epigenomics, and microbiomics. Effective biologic or pharmacologic OM interventions are likely to supplement or stimulate existing physiologic damage-control mechanisms.

Treatment for Oral Mucositis-Current Options and an Update of Small Molecules Under Development.

OPINION STATEMENT: Despite its history as one of the most impactful toxicities associated with cytotoxic cancer therapy, oral mucositis (OM) remains an unmet clinical need which affects hundreds of thousands of patients. Descriptions of its complex pathogenesis have provided mechanistic targets which are being exploited to develop an effective therapeutic intervention. Favorable results of recently completed clinical trials in which agents focused on interrupting the early stages of the mucositis biological cascade were assessed provide reason for optimism, not only for oral mucositis but also for halo indications which share its pathobiogenesis.

Oral side effects of immune checkpoint inhibitor therapy (ICIT): An analysis of 4683 patients receiving ICIT for malignancies at Massachusetts General Hospital, Brigham & Women's Hospital, and the Dana-Farber Cancer Institute, 2011 to 2019.

BACKGROUND: Immune checkpoint inhibitors (ICIs) are increasingly accepted as a treatment option for several cancers. Although various systemic immune-related adverse events (irAEs) have been characterized, the effect of ICIs on the oral cavity and contiguous structures is still poorly understood. METHODS: Electronic medical records of 4683 patients in the Mass General Brigham Registered Patient Data Registry who received ICI therapy (ICIT) between December 2011 and September 2019 were reviewed. Reports of oral conditions were categorized into oral mucosal disorders, xerostomia, and dysgeusia. After applying exclusion criteria, demographic characteristics and clinical features were summarized for the patients who had oral irAEs. RESULTS: In total, 317 patients developed oral conditions that were associated with ICIT (incidence, 6.8%; 317 of 4683 patients). These conditions included xerostomia (68.5%), oral mucosal disorders (33.4%), and dysgeusia (24.0%). In patients with oral irAEs, respiratory cancer (28.4%) was the most common primary cancer, followed by melanoma (26.2%), and head and neck cancer (14.8%). Oral mucosal disorders developed after the initiation of ICIT between 2 and 851 days (between 1 and 1332 days in patients with xerostomia and between 1 and 1455 days in patients with dysgeusia). Of all oral irAEs, 50.9% developed within 3 months, and 85.5% developed within 12 months. CONCLUSIONS: Oral side effects appear to be more common among patients who receive ICIT than has been previously reported. Concomitant cytotoxic regimens may exacerbate the risk of oral adverse events, perhaps representing the sum of the effects of different, but simultaneous or sequential, pathogenic mechanisms. Additional studies are warranted to better characterize oral irAEs and their biologic basis.

The Path to an Evidence-Based Treatment Protocol for Extraoral Photobiomodulation Therapy for the Prevention of Oral Mucositis.

Oral mucositis is a painful complication of hematopoietic stem cell transplantation for which photobiomodulation therapy (PBMT) is a safe and effective intervention. Extraoral delivery of PBMT has clinical advantages over intraoral delivery but requires additional dosimetric considerations due to the external tissue layers through which the light must propagate before reaching the oral mucosa. Additionally, to date there has been no dose modeling study, a task essential to developing a justified treatment protocol. We review here some of the complexities surrounding extraoral photobiomodulation therapy and offer that may help guide researchers toward an evidence-based treatment protocol for the prevention of oral mucositis.