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 ± 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.

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.

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 of 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.

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.

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.

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.

Abstract 1886: Targeting oral squamous cell carcinoma tumor microenvironment through simultaneous modulation of pattern recognition receptors and angiogenic factors using a synthetic polymer-based drug

Squamous cell carcinomas (SCCs) are the dominant form of cancers of the upper aerodigestive tract. Main risk factors are smoking and human papilloma virus (HPV) infection. Despite the HPV vaccination efforts, the number of oropharyngeal cancers (OSCCs) has been steadily increasing especially in males. Standard of care primarily focuses on the surgical removal of cancerous tissues followed by chemoradiation therapy. However, the recurrence rate of OSCCs remains fairly high as the tumor frequently develops therapy resistance and more effective therapeutic regimens are needed. The chronic inflammatory state yet paradoxical immunosuppressive tumor microenvironment has been regarded as a cause of therapy resistance and suggested as a potential therapeutic target. Pattern recognition receptors (PRRs) such as toll-like receptors (TLRs) contribute to pro-inflammatory tissue responses. TLR2 present in the OSCC tumor appears to play important roles in regulating immune responses and promoting pro-inflammatory tumor microenvironment. GM-1111 is a synthetic glycosaminoglycan-based anti-inflammatory molecule that potently inhibits PRRs such as TLR2 and NLRP3 inflammasome. In addition, GM-1111 inhibits multiple angiogenic molecules - CXCL12, VEGF, and FGF2. We hypothesized that GM-1111 might be able to reduce OSCC tumor growth by simultaneously disrupting pro-inflammatory as well as angiogenic signaling. To test this hypothesis, male CD1 nude mice bearing FaDu cell tumor in the back were treated with either (1) vehicle, (2) GM-1111 (30 mg/kg, q.d., s.c.), (3) vehicle with irradiation (2 Gy/day x 5 days), or (4) GM-1111 with irradiation 17 days. Established tumors grew in two phases from slow for the initial 7 days to fast growths during the remaining days. Irradiation- or drug-induced tumor regression was observable about 5 days after the last radiation therapy (day 10). Compared to the vehicle only (1) treatment group, GM-1111 treated animals (groups 1 vs. 2: p = 0.0032; groups 1 vs. 3: p < 0.0001; groups 1 vs. 4: p < 0.0001) demonstrated significantly reduced tumor growth. These results suggest that GM-1111 has a potential to reduce OSCC and further confirm our previous orthotopic human tongue SCC-25 cell xenograft study data.

Citation Format: Won Yong Lee, Frida Ponthan, Stephen T. Sonis. Targeting oral squamous cell carcinoma tumor microenvironment through simultaneous modulation of pattern recognition receptors and angiogenic factors using a synthetic polymer-based drug [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1886.

Phase 2, randomized, double-blind trial of EC-18 versus placebo to mitigate the development and time course of oral mucositis from concomitant chemoradiation for head and neck cancer

12106

Background: Oral mucositis (OM) is a debilitating side effect of concomitant chemoradiotherapy (CRT) for head and neck cancer (HNC). EC-18 may effectively mitigate OM by minimizing the CRT-induced innate immune response. This Phase II, 2-stage trial evaluated safety, tolerability, and efficacy of EC-18 in reducing the duration, incidence, and trajectory of severe OM (SOM) in HNC patients. Methods: Patients (n = 105) with pathologically confirmed oral cavity, oropharynx, hypopharynx, or nasopharynx squamous cell cancers who received intensity-modulated radiation therapy (IMRT; with ≥ 55 Gy on ≥ 2 oral sites) and weekly or tri-weekly cisplatin were studied. In Stage 1, 24 patients were randomized (n = 6 per arm) to receive 500, 1000, or 2000 mg of EC-18, or placebo. Following independent Data Safety Monitoring Board review, 81 patients in Stage 2 received EC-18 2000 mg (n = 41) or placebo (n = 40) throughout CRT. WHO OM grade was assessed twice weekly during IMRT and then once weekly for up to 6 weeks post-IMRT. The primary efficacy endpoint was duration of SOM during the active and short-term follow-up (STFU) periods in the compliant per-protocol population (PP). Much of Stage 2 was conducted during peak periods of the COVID-19 pandemic which measurably impacted patient compliance relative to test medication dosing and planned radiation. Consequently, to assess efficacy most accurately, the PP population was analyzed (with at least 4 weeks of study drug dosing, minimum cumulative radiation of 55 Gy, 80% study drug compliance in the first 28 days of dosing, and without using not-allowed-therapy). Results: Patient demographics and baseline characteristics were balanced between groups. Adverse events (AEs) were comparable amongst cohorts without drug-related severe AEs. In the PP, the median duration of SOM from baseline through STFU was 0 day in the EC-18 group (n = 22) v 13.5 days in the placebo group (n = 20). SOM incidence through STFU (45.5% v 70%) and opioid use (time to onset: 32.3 v 26.0 days; and duration: 32.8 v 37.5 days) favored EC-18 v placebo. Results of the covariates analyses suggested that EC-18 favorably impacted SOM incidence in patients who experienced SOM treated with weekly low-dose cisplatin (n = 26; 37.5% v placebo 70.0%) and HPV+ tumors (n = 29; 35.3% v placebo 66.7%; Table). One-year long-term follow-up for tumor outcomes is ongoing. Conclusions: EC-18 safely mitigated the development and the time course of SOM in CRT-treated HNC patients. In addition, EC-18 may provide substantial benefits to subpopulations of HPV+ HNC patients treated with low dose cisplatin. Clinical trial information: NCT03200340. [Table: see text]

Phase 2 pilot trial of RRx-001 as an anti-mucositis agent in patients with head and neck cancer treated with chemoradiation (PREVLAR)

6078

Background: Severe oral mucositis (SOM) is a dose limiting toxicity during radiotherapy and cisplatin for head and neck cancers. The aim of this 4-arm randomized controlled pilot trial was to evaluate the efficacy of different schedules of a novel radioprotectant, RRx-001 versus standard-of-care (SOC), to reduce duration, time to onset and incidence of SOM in patients received cisplatin-based chemoradiotherapy (CRT) for oral cavity or oropharyngeal cancer (OCC). Methods: Patients with locally advanced OCC treated with definitive or postoperative CRT were randomized to receive RRx-001 by 15-minute intravenous infusion in one of three different schedules versus none. The days and severity of mucositis were prospectively evaluated. Oral mucositis was assessed weekly during and after CRT as well as 28 days after completion. The pre-specified efficacy endpoints were duration of grade 3-4 SOM, resolution of SOM, time to onset of SOM and incidence of SOM. Results: A total of 53 patients were enrolled between June 2018 and July 2019 across 11 institutions. Forty-five (out of 53) patients received study drug and were efficacy evaluable. RRx-001 were well tolerated with no associated serious adverse events. All RRx-001 arms numerically outperformed SOC on the pre-specified efficacy measures, and the greatest effect estimate was observed on Arm 1 (RRx-001 pretreatment only + CRT). The following endpoints favored treatment with RRx-001. Median SOM duration by treatment was 22 and 40 days for Arm 1 and SOC respectively. Time to onset of SOM was by 38 days (Arm 1) vs. 26 days (SOC). On Arm 1, 83% of patients had SOM resolution vs 60% on SOC). Gastrostomy requirement was reduced by 45%. No patients on Arm 1 developed grade 4 mucositis vs 30% developed grade 4 mucositis on the SOC arm. Furthermore, the incidence of oropharyngeal dysphagia, which can substantially impair nutrition, was reduced by treatment with RRx-001, occurring at 50% vs 70% for Arm 1 vs SOC respectively. Treatment with RRx-001 resulted in highly significant decrease in the duration of SOM through 60 Gy with a median SOM of 1 day vs 17 days for Arm 1 vs SOC respectively (Wilcoxon rank-sum test p < 0.001). Median cumulative cisplatin dose was significantly greater for RRx-001 Arm 1 than SOC (557.4 mg vs. 438 mg, Wilcoxon p = 0.025). Conclusions: Compared with SOC, SOM among RRx-001-treated patients given 3 different treatment schedules was less severe, of shorter duration, demonstrated delayed time to onset and resolved earlier. Overall, the incidence, duration and severity of SOM and dysphagia was reduced. The safety profile of RRx-001 was similar to SOC. These results will inform the design of a Phase 3 pivotal study of RRx-001 in the prevention of SOM in at-risk cancer patients. Clinical trial information: NCT03515538.

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.

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.

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.

Phase Ib, international, dose-escalation study to evaluate the safety, pharmacokinetics (PK) and efficacy of ST-617 for the attenuation of oral mucositis (OM) in patients receiving chemoradiation (CRT) for head and neck (H&N) cancer

6075

Background: OM is a common, painful, and costly toxicity associated with cytotoxic regimens used to treat H&N cancers, which may result in radiotherapy treatment interruptions to negatively impact tumor control. There are currently no approved interventions to successfully prevent or delay OM onset among patients being treated with radiation therapy, with or without concomitant chemotherapy (CRT). Oxidative stress is a critical event in OM’s pathogenesis. Through its effect on Nrf2, ST-617 has marked anti-oxidative activity/properties. Supportive Therapeutics is developing ST-617, a dithioethione, for the attenuation of OM onset, duration and severity. The objective of this trial was to assess the safety, tolerability, PK, PD and efficacy of ST-617 in patients at high risk of severe OM (SOM). Methods: A dose escalation trial in which ST-617 administered as an oral suspension, 1-2 hours before the administration of daily RT fractions was performed at 9 study sites in South Africa and Australia. Eighteen patients with diagnoses of oral or oropharyngeal CA were enrolled (up to 6 pts/dose). Patients received concomitant cisplatin either weekly or tri-weekly. ST-617 was administered 3 days prior to CRT, and then continuing daily until the end of treatment. Safety outcomes, using CTCAE criteria (v 4.03) were used. Dose escalation occurred in the absence of toxicity. OM occurrence and severity were assessed by trained and validated evaluators using WHO, NCI-CTC and RTOG criteria; scores were centrally assigned. The primary efficacy endpoints included the incidence and duration of SOM (WHO grades 3 or 4) vs historical controls. PD tracking measured total ROS/RNS, GSH/GSSG, regulation in plasma and buccal epithelial cells. Results: 17 pts completed the 50, 100 and 150mg/day with no safety issues. No early dose limiting toxicity (DLT) or serious Adverse Event linked to ST-617 were observed. AEs observed were mainly nausea which is usually associated with CRT as expected. The 100 mg/day dose has been well tolerated with no grade 4 OM. No CRT dose interruptions or delays due to OM has been observed. Total ROS/RNS levels in plasma and buccal samples show significant decrease with increased ST-617 dosing from 50 to 100 mg/day. Conclusions: ST-617 administration was safe at all doses tested. The course and severity of patients treated with ST-617 compared favorably with historical controls. Mechanistic correlation between ROS/RNS levels was seen. A randomized, controlled, double blind trial is planned with the recommended dose of 100mg/day. Clinical trial information: 20180138.

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.

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.

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.

Abstract 585: Colitis in tumor-bearing mice undergoing checkpoint inhibitor therapy

Checkpoint inhibitor (CPI) therapy represents an exciting new treatment option for patients with advanced malignancies. However, several adverse events (AEs) that affect multiple body systems are associated with CPI treatment, including colitis. The mechanisms mediating these AEs remain to be fully elucidated. That mice treated with CPI fail to develop the spectrum of AEs observed in patients hampers the field's ability to develop supportive care treatment options. Here we sought to examine colitis in tumor bearing mice undergoing CPI therapy. Briefly, naïve TH cells and Treg cells were harvested from C57Bl/6 donor mice and were adoptively transferred into RAG2−/- recipients. Animals were inoculated with B16F10 cells into the left flank seven days later. T cell engraftment was assessed after 13 days, and animals were randomized into treatment groups by rate of T cell engraftment; animals were treated Q3D with either vehicle or anti-CTLA4 for an additional four weeks. Animals were monitored for body weight loss and systemic AEs (gastrointestinal, pulmonary, neurological) daily and tumor volume was measured by digital caliper three times per week. Extent of colitis was evaluated by video endoscopy at several timepoints and colitis severity was scored using a 0-4 scale. Animals developed body weight loss approximately two weeks after T cell transfer and CPI treatment increased the severity of body weight loss observed. Colitis was seen by video endoscopy within a similar timeframe. Mean tumor volume was decreased in animals treated with CPI as compared to those treated with vehicle. Diarrhea, pulmonary symptoms, and neurological symptoms were observed in a subset of animals over the study period; anti-CTLA4 treatment increased the overall incidence of pulmonary symptoms. These data demonstrate the utility of this system for assessment of colitis or other AE supportive care treatment options in the context of CPI-treated, tumor-bearing mice.

Citation Format: Caitlin S. Parello, Benjamin G. Cuiffo, Kasey Reardon, Alexandria Fusco, Brett Van Dam, Gregory D. Lyng, Stephen T. Sonis. Colitis in tumor-bearing mice undergoing checkpoint inhibitor therapy [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 585.

Oral Mucositis Due to High-Dose Chemotherapy and/or Head and Neck Radiation Therapy

Oral mucositis is a common side-effect associated with conventional cancer therapy and has also recently been reported in association with newly emerging cancer therapies. It is characterized as an inflammation of the oral mucous membranes accompanied by many complex mucosal and submucosal changes. Ulcerative oral mucositis can cause significant oral pain, impair nutritional intake, lead to local or systemic infection, and cause significant economic cost. In addition, it may necessitate interruptions in cancer therapy, thus adversely affecting patient prognosis. This review presents the current understanding of the pathogenesis of mucositis and discusses evidence-based clinical management strategies for oral mucositis. In addition, key research questions for future investigation are identified, followed by a discussion of strategies to promote development and funding of the needed research.

ROMAN: Reduction in oral mucositis with avasopasem manganese (GC4419)–Phase III trial in patients receiving chemoradiotherapy for locally advanced, nonmetastatic head and neck cancer

TPS6596

Background: Approximately 70% of patients receiving intensity-modulated radiotherapy (IMRT) plus cisplatin for locally advanced head and neck cancer (HNC) develop SOM, defined as WHO Grade 3 or 4, which limits patients' ability to eat solids (Gr 3) or liquids (Gr 4, requiring enteral nutrition). An RT-induced burst of superoxide initiates oral mucositis (OM) development. GC4419, a superoxide dismutase mimetic, interrupts this process by converting superoxide to H2O2. It showed promising reduction of SOM in a published open-label Phase 1b/2a trial (IJROBP 1 Feb 2018). In a subsequent randomized, double-blind placebo-controlled trial in 223 patients receiving IMRT/cisplatin for HNC (ASCO 2018), 90 mg of GC4419 administered M-F prior to IMRT demonstrated statistically significant reduction in SOM duration (p=0.024, median 1.5 days @ 90 mg vs. 19 days placebo) and meaningful reductions @ 90 mg in SOM incidence (43% vs. 65%) and severity (incidence of Grade 4, 16% vs. 30%). The safety results were acceptable and consistent with the known toxicities of IMRT/cisplatin. Methods: 335 patients at multiple centers in the U.S. and Canada with locally-advanced, nonmetastatic head and neck cancer (oral cavity/oropharyngeal) receiving 70 Gy IMRT (>50 Gy to > 2 oral sites) plus cisplatin (40 mg/m2 qwk x 6-7, or 100 mg/m2 q3wk x 3) are being randomized (double-blinded) 3:2 to 90 mg of GC4419 or placebo, M-F before each RT fraction. Enrollment is stratified by cisplatin schedule and treatment setting (definitive vs. post-op). OM by the WHO scale will be assessed twice weekly during RT & weekly for 2 weeks post RT. The primary efficacy endpoint is incidence of SOM through the end of IMRT. Secondary efficacy endpoints include severity (incidence of Grade 4 OM through the end of IMRT), & days of SOM (days from first to last SOM for all patients, with patients never developing SOM having 0 days of SOM by definition). Days of SOM for the subset developing SOM will be analyzed descriptively. Patients will be followed for one year post IMRT for tumor progression/recurrence and for two years for survival. Clinical trial information: NCT03689712 .

Results of a randomized, open-label, multicenter trial to assess the safety, dose, and schedule ofRRx-001(001) in reducing incidence, severity and duration of severe oral mucositis (SOM) inpatients receiving concomitant chemoradiation (CRT) for advanced head and neck cancer (HNC)

12081

Background: SOM occurs in 70% of patients receiving CRT for HNC with consequent pain, treatment interruptions and increased costs of care. Supraphysiologic levels of oxidative stress are key SOM initiators. 001 activates nuclear factor erythroid related factor 2 (Nrf2) increasing expression of multiple antioxidant genes including superoxide dismutase glutathione peroxidase and glutathione S-transferase. This trial examined the effect of dose and schedule on safety and efficacy of 001. Primary efficacy endpoint was duration of SOM (WHO criteria assessed); secondary endpoints included time to onset, incidence grade 4 through 60Gy and 70Gy. Methods: Locally advanced HNC treated with definitive or postoperative CRT (cisplatin + RT) received one of 3 001 schedules: (ARM1) 2 doses/wk for 2 weeks (prior to) CRT. ARMS 2, 3: prior to + 2 doses or 6 doses with CRT respectively or standard of care (SOC). Results: 53 patients randomized, 45 evaluable. Benefit trends for endpoints were consistent across all 3 001 arms with greatest effect size in pre-treatment only, ARM1. Compared to SOC, 001 reduced duration of SOM by 45% (40 vs 22 days). Through 60Gy and 70Gy a reduction of 95% and 79% in duration SOM was also observed (17 vs 1 day, and 23 vs 5 days) respectively. No patients in ARM1 developed grade 4, (0% vs SOC 30%). Side effects were comparable to SOC. Conclusions: In this small, open label trial, 001 demonstrated a favorable risk-benefit profile supported by reductions in overall SOM duration including through 60Gy and 70Gy with no grade ARM1 was most effective suggesting short periods of Nrf2 activation before CRT oxidative stress generation may increase the threshold and buffering capacity of upregulated antioxidants. Larger, blinded trials, confirming the observed dose, schedule and treatment effects are warranted. Clinical trial information: NCT03515538 .

Oral adverse events in cancer patients treated with immune checkpoint inhibitors

e15106

Background: Immune-checkpoint inhibitors (ICIs) are increasingly used to treat a variety of cancers. Immune-related adverse events (irAEs) have been reported. Oral manifestations of irAEs include stomatitis, oral ulcers, and xerostomia. However, the trajectory and frequency of oral irAEs remain unclear. This study aims to evaluate the prevalence, trajectory and nature of oral irAEs and their association with primary cancer diagnosis and other irAEs. Methods: A retrospective electronic chart review using the Partners Research Patient Data was performed for all patients treated with ICIs at Partners Healthcare hospitals and the Dana-Farber Cancer Institute between 12/2011 and 9/2019. Keywords specific to oral irAE such as oral mucositis, stomatitis or mouth sore were used. We collected data on demographics, cancer features, treatments, and characteristics of oral irAEs. Results: 822 of 4683 patients who received ICIs therapy were identified by keyword filtering. Lung cancer, gastrointestinal cancer, and skin cancer (including melanoma) were the most common types of primary malignancies with a frequency of 35.5%, 12.4 % and 11.7%, respectively. Oral irAEs were identified in 106 patients with the median age of 69 (range: 29-92) years and the female to male ratio of 1:1. 57.5% (n = 61) presented with symptomatic oral mucosal lesions. 47.2% (n = 50) had xerostomia and 17.0% (n = 18) had dysgeusia. The median time from the date of ICIs initiation to the date of oral irAE onset was 105 days (range: 2-631 days) in patients presented with oral mucosal lesions, 103 days (2-860 days) in xerostomia patients, and 156 days (range: 5-836 days) in dysgeusia patients. Melanoma was the most common cancer seen in oral irAE patients (30.2%), followed by lung cancer (26.4%) and oral/oropharyngeal cancer (12.3%). 60, 42, and 12 patients received pembrolizumab, nivolumab, and ipilimumab, respectively. 86.8% of oral irAE patients received only one type of ICIs therapy. Concomitant cutaneous, intestinal, and rheumatological irAEs were commonly reported with a frequency of 19.4%, 15.3%, and 12.2%, respectively in those patients. Conclusions: Oral irAEs can present with both acute and chronic onset in patients with ICIs therapy but are not as common as oral AEs associated with conventional cytotoxic regimens. While data relative to capturing oral irAEs is still preliminary, the current provides insight into their nature and course. Prospective studies focused on assessing the impact of ICI on oral irAEs are likely to provide additional insight into the character, course and impact of these conditions.

Robust pathway sampling in phenotype prediction. Application to triple negative breast cancer

Background

Phenotype prediction problems are usually considered ill-posed, as the amount of samples is very limited with respect to the scrutinized genetic probes. This fact complicates the sampling of the defective genetic pathways due to the high number of possible discriminatory genetic networks involved. In this research, we outline three novel sampling algorithms utilized to identify, classify and characterize the defective pathways in phenotype prediction problems, such as the Fisher’s ratio sampler, the Holdout sampler and the Random sampler, and apply each one to the analysis of genetic pathways involved in tumor behavior and outcomes of triple negative breast cancers (TNBC). Altered biological pathways are identified using the most frequently sampled genes and are compared to those obtained via Bayesian Networks (BNs).

Results

Random, Fisher’s ratio and Holdout samplers were more accurate and robust than BNs, while providing comparable insights about disease genomics.

Conclusions

The three samplers tested are good alternatives to Bayesian Networks since they are less computationally demanding algorithms. Importantly, this analysis confirms the concept of “biological invariance” since the altered pathways should be independent of the sampling methodology and the classifier used for their inference. Nevertheless, still some modifications are needed in the Bayesian networks to be able to sample correctly the uncertainty space in phenotype prediction problems, since the probabilistic parameterization of the uncertainty space is not unique and the use of the optimum network might falsify the pathways analysis.

Phase IIb, Randomized, Double-Blind Trial of GC4419 Versus Placebo to Reduce Severe Oral Mucositis Due to Concurrent Radiotherapy and Cisplatin For Head and Neck Cancer

PURPOSE

Oral mucositis (OM) remains a common, debilitating toxicity of radiation therapy (RT) for head and neck cancer. The goal of this phase IIb, multi-institutional, randomized, double-blind trial was to compare the efficacy and safety of GC4419, a superoxide dismutase mimetic, with placebo to reduce the duration, incidence, and severity of severe OM (SOM).

PATIENTS AND METHODS

A total of 223 patients (from 44 institutions) with locally advanced oral cavity or oropharynx cancer planned to be treated with definitive or postoperative intensity-modulated RT (IMRT; 60 to 72 Gy [≥ 50 Gy to two or more oral sites]) plus cisplatin (weekly or every 3 weeks) were randomly assigned to receive 30 mg (n = 73) or 90 mg (n = 76) of GC4419 or to receive placebo (n = 74) by 60-minute intravenous administration before each IMRT fraction. WHO grade of OM was assessed biweekly during IMRT and then weekly for up to 8 weeks after IMRT. The primary endpoint was duration of SOM tested for each active dose level versus placebo (intent-to-treat population, two-sided α of .05). The National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.03, was used for adverse event grading.

RESULTS

Baseline patient and tumor characteristics as well as treatment delivery were balanced. With 90 mg GC4419 versus placebo, SOM duration was significantly reduced (P = .024; median, 1.5 v 19 days). SOM incidence (43% v 65%; P = .009) and severity (grade 4 incidence, 16% v 30%; P = .045) also were improved. Intermediate improvements were seen with the 30-mg dose. Safety was comparable across arms, with no significant GC4419-specific toxicity nor increase of known toxicities of IMRT plus cisplatin. The 2-year follow-up for tumor outcomes is ongoing.

CONCLUSION

GC4419 at a dose of 90 mg produced a significant, clinically meaningful reduction of SOM duration, incidence, and severity with acceptable safety. A phase III trial (ROMAN; ClinicalTrials.gov identifier: NCT03689712) has begun.

Abstract 511: An assessment of pre-conditioning regimens for optimal hCD34+ hematopoietic stem cell humanization of NSGTMmice

Humanized immune system (HIS) mice - immunocompromised Nod.Cg-Prkdcscid Il2rgtm1Wjl/SzJ animals in which the immune system has been humanized by the engraftment of CD34+ hematopoietic stem cells (HSC), peripheral blood mononuclear cells (PBMC), or other human cells/tissues - represent an important tool in pre-clinical oncology research. Here we investigated several pre-conditioning regimens (Busulfan pre-treatment or total body irradiation (TBI)) to determine which would yield maximum human leukocyte engraftment and lineage diversity. Animals were pre-treated either one or two doses of Busulfan (25 mg/kg) or varying doses of TBI (1.75, 2.0, or 2.5 Gy). One to two days later, animals received an adoptive transfer of native hCD34+ HSCs. Engraftment was monitored by flow cytometry assessment of peripheral blood four weeks after adoptive-transfer, and every four weeks thereafter through experiment termination at Week 16. Upon termination, spleen and bone-marrow were assessed for various leukocyte populations by flow cytometry. Animals undergoing pre-conditioning displayed increased human CD45+ cell engraftment at all timepoints as compared to animals without pre-conditioning, with animals treated with two doses of Busulfan demonstrating the greatest human CD45+ engraftment at all timepoints and reaching statistical significance at endpoint (vs no pre-conditioning; p&lt;0.05). Diversity of leukocyte cell types (B cells, T cells, NK cells, and other hCD45+) in the bone-marrow was similar across pre-treatment paradigms, however for some lineages, representation in the bone-marrow was significantly altered between pre-conditioning type. The absolute number of T or B cells were increased in TBI and Busulfan treated groups, respectively, whereas NK cells as a percentage of singlets were increased in TBI treated groups. The diversity of leukocyte cell types in the spleen was likewise similar across groups, with B cells dominating. These data provide important insights into the utility of various pre-conditioning regimens for the humanization of NSG mice for pre-clinical oncology research, and demonstrate that the optimum pre-conditioning regimens should be selected based on treatment target.

Citation Format: Caitlin S. Parello, Benjamin G. Cuiffo, Alexandria Kury, Kasey Reardon, Brett Van Dam, Sallyann Vu, Catarina Costa, Veronica Ritchie, Gavin Gagnon, Timothy Bateson, Samantha Rogers, Gregory D. Lyng, Stephen T. Sonis. An assessment of pre-conditioning regimens for optimal hCD34+ hematopoietic stem cell humanization of NSGTMmice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 511.

Roman: Reduction in oral mucositis with avasopasem manganese (GC4419)—Phase 3 trial in patients receiving chemoradiotherapy for locally-advanced, non-metastatic head and neck cancer

TPS6096

Background: Approximately 70% of patients receiving intensity-modulated radiotherapy (IMRT) plus cisplatin for locally advanced head and neck cancer (HNC) develop SOM, defined as WHO Grade 3 or 4, which limits patients' ability to eat solids (Gr 3) or liquids (Gr 4, requiring enteral nutrition). An RT-induced burst of superoxide initiates oral mucositis (OM) development. GC4419, a superoxide dismutase mimetic, interrupts this process by converting superoxide to H2O2. It showed promising reduction of SOM in a published open-label Phase 1b/2a trial (IJROBP 1 Feb 2018). In a subsequent randomized, double-blind placebo-controlled trial in 223 patients receiving IMRT/cisplatin for HNC (ASCO 2018), 90 mg of GC4419 administered M-F prior to IMRT demonstrated statistically significant reduction in SOM duration (p=0.024, median 1.5 days @ 90 mg vs 19 days placebo) and meaningful reductions @ 90 mg in SOM incidence (43% vs 65%) and severity (incidence of Grade 4, 16% vs 30%). The safety profile was acceptable and consistent with the known toxicities of IMRT/cisplatin. Methods: 335 patients at multiple centers in the U.S. and Canada with locally-advanced, nonmetastatic head and neck cancer (oral cavity/oropharyngeal) receiving 70 Gy IMRT (>50 Gy to > 2 oral sites) plus cisplatin (40 mg/m2 qwk x 6-7, or 100 mg/m2 q3wk x 3) are being randomized (double-blinded) 3:2 to 90 mg of GC4419 or placebo, M-F before each RT fraction. Enrollment is stratified by cisplatin schedule and treatment setting (definitive vs post-op). OM by the WHO scale will be assessed twice weekly during RT & weekly for 2 weeks post RT. The primary efficacy endpoint is incidence of SOM through the end of IMRT. Secondary efficacy endpoints include severity (incidence of Grade 4 OM through the end of IMRT), & days of SOM (days from first to last SOM for all patients, with patients never developing SOM having 0 days of SOM by definition). Days of SOM for the subset developing SOM will be analyzed descriptively. Patients will be followed for one year post IMRT for tumor progression/recurrence and for two years for survival. Supported by Galera Therapeutics, Inc. Clinical trial information: NCT03689712.

CLO19-037: Reducing the Duration, Incidence and Severity of Mucosal Injury Due to Cancer Radiation therapy (RT); Positive Randomized Phase 2b Trial Results With GC4419 (Avasopasem Manganese), a Small Molecule Superoxide (SO) Dismutase (SOD) Mimetic

Introduction: RT-induced SO contributes to initiation of mucosal injury; eg, oral mucositis (OM) and esophagitis. GC4419 specifically mimics SOD’s dismutation of SO to hydrogen peroxide (H2O2), interdicting OM initiation. GC4419 reduced RT-severe OM (SOM) in a hamster cheek pouch model, and protected mucosa and other normal tissues from radiation-induced injury in other animal models. In a published phase 1b/2a open-label trial (Anderson et al, IJROBP, 1 Feb 2018), GC4419 attenuated SOM in patients (Pts) receiving intensity-modulated RT (IMRT) plus concurrent cisplatin (CDDP) for locally advanced head & neck cancer (HNC). Objectives: Determine whether GC4419 reduces duration, incidence, & severity of SOM. Methods: Pts with locally advanced oral cavity or oropharyngeal cancer; definitive or postoperative intensity-modulated (IM)RT (approximately 70 Gy [>50 Gy to > 2 oral sites]) plus CDDP (weekly or q3wk) were randomized (stratification: tumor HPV status, CDDP schedule) to 30 or 90 mg of GC4419, or placebo (PBO), 60-minute IV infusion, M–F, ending <60 minutes before IMRT delivered in 35 fractions over 7 weeks. WHO grade OM was assessed by trained evaluators biw during IMRT & qwk for up to 8 wks after IMRT. Primary endpoint: duration of SOM. Efficacy was tested for each active dose vs PBO (ITT population) by a sequential, conditional approach (2-sided alpha, 0.05). Results: 223 pts (44 sites): 90 mg (n=76), 30 mg (n=73), or PBO (n=74). Baseline patient and tumor characteristics and treatment delivery were balanced. Efficacy: At 90 mg GC4419 vs PBO, duration of SOM was significantly reduced (median, 1.5 vs 19 d; P=.024). SOM incidence (43% vs 65%; P=.009), and grade 4 incidence (16% vs 30%; P=.045) also improved. There were intermediate improvements with 30 mg. Safety was comparable across arms; no significant GC4419-specific toxicity; other known toxicities of IMRT/CDDP were not increased. Conclusions: GC4419 demonstrated a significant, clinically meaningful reduction of SOM duration, and dose-dependent improvements in other SOM parameters, with acceptable safety. A confirmatory phase 3 trial (NCT03689712) is in progress. Clinical trials to reduce RT-related esophagitis are also planned.

Biomarkers Associated with Lymphedema and Fibrosis in Patients with Cancer of the Head and Neck

BACKGROUND

This study examined interrelationships of selected interleukins (ILs), tumor growth factors, matrix metalloproteinases (MMPs), and C-reactive protein, interferon-gamma (IFN-γ), and tumor necrosis factor α (TNF-α) with lymphedema/fibrosis in patients with head and neck cancer (HNC).

METHODS AND RESULTS

Patients newly diagnosed with ≥Stage II HNC (N = 100) were assessed for external/internal lymphedema and/or fibrosis before treatment, end-of-treatment, and at regularly established intervals through 72 weeks posttreatment and blood was drawn. Data from 83 patients were analyzed. Group-based trajectory modeling generated patient groups with similar longitudinal biomarker and lymphedema-fibrosis trajectories. Area-under-the-curve (AUC) values were also generated for each biomarker and severity of lymphedema-fibrosis. Associations among and between biomarkers and lymphedema-fibrosis trajectories and AUCs were tested (log-likelihood chi-square, correlations). The strongest evidence for the association of biomarkers with the overall and trajectory patterns and severity of lymphedema-fibrosis was observed for IL-6, IL-1β, TNF-α, TGF-β1, and MMP-9 (all p < 0.05). Convergence of joint trajectory patterns and AUC were observed with IL-6 with all lymphedema-fibrosis trajectories and internal lymphedema AUC. IL-1β trajectories converged with external lymphedema trajectories and all lymphedema-fibrosis AUCs. TNF-α and TGF-β1 converged most strongly with fibrosis in terms of trajectory patterns. However TNF-α demonstrated stronger association with lymphedema-fibrosis AUC (fibrosis: rs = 0.49). MMP-9 demonstrated convergence with lymphedema-fibrosis AUCs (lymphedema: 0.43-0.42; fibrosis: 0.35).

CONCLUSION

Systemic levels of selected mediators of proinflammatory processes track with acute and chronic clinical phenotypes of lymphedema/fibrosis in HNC patients suggesting their potential role in the pathogenesis of these conditions.

Abstract 1146: Early PD-1 inhibition abrogates PBMC engraftment in a triple-humanized (tumor/PBMC/MSC) bioluminescent orthotopic model of pancreatic cancer

Accuracy of context is critical in efforts to improve the translational potential of preclinical oncology models. Pancreatic cancer has high mortality and current models are insufficient for advancing therapeutics. Here we note key observations in the ongoing development of a new pancreatic cancer mouse model designed to enable translational immuno-oncology and/or tumor microenvironment (TME) targeted therapeutics in a “triple-humanized” orthotopic context including: 1) tumor: bioluminescent PD-L1+ BxPC3-Red-FLuc human pancreatic ductal adenocarcinoma (PDAC) cells surgically implanted into the pancreas of aged NSG™ mice; 2) T cells: human peripheral blood mononuclear cells (PBMCs) derived from a healthy donor and shown to respond to PD-1 inhibition; and 3) tumor-tropic stem-like stromal cells: bone-marrow (BM) derived human mesenchymal stem/stromal cells (MSCs) derived from a healthy donor. MSCs are described to home to PDAC stroma where they react to TME and contribute to PDAC progression via pleiotropic therapeutic refractory effects including stromal remodeling favoring effector immunosuppression, angiogenesis and desmoplasia. To assess the role of MSCs in PDAC response to PD-1 blockade, we injected BxPC3-Red-FLuc cells into the pancreas of 14-week NSG™ mice, +/-MSCs; coinjected animals received weekly MSCs bolus injections to simulate continuous migration from BM. Some groups concurrently received PBMCs characterized for aPD-1 response. Ten days after injection with human cells, animals were randomized by tumor radiance into treatment groups administered +/- 150µg anti-human PD-1 mAb (clone: EH12.2H7) (aPD-1) 2x/week. Immunohistochemistry analysis of tumors was performed. Engraftment/characterization of PBMCs was assessed by flow cytometry of PB in-life and spleen at terminus. MSCs alone did not increase primary tumor growth, but PBMC engraftment was increased by administration of MSC. Tumor growth was decreased with PBMC but primary tumor growth was increased in animals receiving PBMC+MSC compared to PBMC alone. The antigen-experienced status of the T cells was not affected by MSC treatment. In contrast, the diversity of engrafting T cells was increased by MSC treatment. Strikingly, aPD-1 treatment completely suppressed PBMC engraftment, regardless of MSC presence. This work details ongoing development of a contextually improved “triple-humanized” mouse model of pancreatic cancer. Key findings agree with recent findings of the importance of timing in aPD-1 treatment in humanized models and clinical applications.

Citation Format: Benjamin G. Cuiffo, Caitlin S. Parello, Chelsea Ritchie, Alexandra Kury, Scott Anderson, Gregory D. Lyng, Stephen T. Sonis. Early PD-1 inhibition abrogates PBMC engraftment in a triple-humanized (tumor/PBMC/MSC) bioluminescent orthotopic model of pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1146.

Genomic data integration in chronic lymphocytic leukemia

BACKGROUND

B-cell chronic lymphocytic leukemia (CLL) is a heterogeneous disease and the most common adult leukemia in western countries. IgVH mutational status distinguishes two major types of CLL, each associated with a different prognosis and survival. Sequencing identified NOTCH1 and SF3B1 as the two main recurrent mutations. We described a novel method to clarify how these mutations affect gene expression by finding small-scale signatures that predict the IgVH, NOTCH1 and SF3B1 mutations. We subsequently defined the biological pathways and correlation networks involved in disease development, with the potential goal of identifying new drugable targets.

METHODS

We modeled a microarray dataset consisting of 48807 probes derived from 163 samples. The use of Fisher's ratio and fold change combined with feature elimination allowed us to identify the minimum number of genes with the highest predictive mutation power and, subsequently, we applied network and pathway analyses of these genes to identify their biological roles.

RESULTS

The mutational status of the patients was accurately predicted (94-99%) using small-scale gene signatures: 13 genes for IgVH, 60 for NOTCH1 and 22 for SF3B1. LPL plays an important role in the case of the IgVH mutation, whereas MSI2, LTK, TFEC and CNTAP2 are involved in the NOTCH1 mutation, and RPL32 and PLAGL1 are involved in the SF3B1 mutation. Four high discriminatory genes (IGHG1, MYBL1, NRIP1 and RGS1) are common to these three mutations. The IL-4-mediated signaling events pathway appears to be involved as a common mechanism and suggests an important role of the immune response mechanisms and antigen presentation.

CONCLUSIONS

This retrospective analysis served to provide a deeper understanding of the effects of the different mutations in CLL disease progression, with the expectation that these findings will be clinically applied in the near future to the development of new drugs.

Phase II investigational oral drugs for the treatment of radio/chemotherapy induced oral mucositis

INTRODUCTION

Oral mucositis is a significant unmet clinical need for many cancer patients. The biological complexity of mucositis' pathogenesis provides a number of mechanistic targets suitable as pharmacologic targets. The diversity of targets has stimulated drug development in search of an effective intervention. In this paper, we review a range of agents that are currently being evaluated.

AREAS COVERED

Drugs for management of oral mucositis vary in formulation, route of administration and biological target. Most propose to interrupt the initiation of injury by suppressing activation of the innate immune response or countering oxidative stress, or minimizing downstream inflammatory responses. Overwhelmingly, the population most studied is patients being treated with concomitant chemoradiation for cancers of the head and neck as this is the cohort that most consistently suffers severe mucositis for long periods of time. The Phase 2 pipeline is robust. Preliminary data reported for a number of agents is optimistic. Genomics may be important in interpreting and comparing responses to agents across widely demographically diverse populations.

EXPERT OPINION

Oral mucositis remains a significant toxicity for patients undergoing cancer treatment. Incremental reports of successes have been noted for a number of targeted agents.

Impact of the insurance type of head and neck cancer patients on their hospitalization utilization patterns

BACKGROUND

Head and neck cancer (HNC) patients with Medicaid, Medicare, or no insurance show poor outcomes in comparison with privately insured patients. It was hypothesized that nonprivate insurance coverage biases the selection of the treatment site to favor hospitals that are not associated with optimum treatment outcomes. This study assessed the relation between the insurance type of HNC patients and the hospital type for inpatient care.

METHODS

Adult HNC patients were identified from the Nationwide Inpatient Sample (2012 and 2013). The primary exposure was the insurance provider type. The outcome was the hospital type, which was classified by the hospital's ownership and its location and teaching status. Multivariate multinomial logistic regression models were constructed to control for the patient's age, sex, race, income, mortality risk, and geographic location. The analysis was weighted and was adjusted for multiple comparisons.

RESULTS

In all, 37,466 HNC patients representing 187,330 patients nationally were identified. After adjustments for age, sex, race, income, and mortality risk, in comparison with privately insured patients, Medicaid, Medicare, and uninsured patients demonstrated 1.14 to 2.29 increased odds of undergoing treatment at rural, urban nonteaching, private investor-owned, or government (nonfederal) hospitals (P < .05). This trend remained apparent even after adjustments for the geographic location.

CONCLUSIONS

Uninsured patients or patients insured by government programs predominantly underwent care for HNC at hospital types most often associated with inferior survival outcomes. This finding could explain some proportion of insurance-related disparities in HNC outcomes. Further studies are warranted to determine whether interventions to promote equitable access to optimal hospital settings for patients, regardless of their insurance type, might improve outcomes among nonprivate insurance holders. Cancer 2018;124:760-8. © 2017 American Cancer Society.

Phase 1b/2a Trial of the Superoxide Dismutase Mimetic GC4419 to Reduce Chemoradiotherapy-Induced Oral Mucositis in Patients With Oral Cavity or Oropharyngeal Carcinoma

PURPOSE

To assess the safety of the superoxide dismutase mimetic GC4419 in combination with radiation and concurrent cisplatin for patients with oral cavity or oropharyngeal cancer (OCC) and to assess the potential of GC4419 to reduce severe oral mucositis (OM).

PATIENTS AND METHODS

Patients with locally advanced OCC treated with definitive or postoperative intensity modulated radiation therapy (IMRT) plus cisplatin received GC4419 by 60-minute intravenous infusion, ending <60 minutes before IMRT, Monday through Friday for 3 to 7 weeks, in a dose and duration escalation study. Oral mucositis was assessed twice weekly during and weekly after IMRT.

RESULTS

A total of 46 patients received GC4419 in 11 separate dosing and duration cohorts: dose escalation occurred in 5 cohorts receiving 15 to 112 mg/d over 3 weeks (n=20), duration escalation in 3 cohorts receiving 112 mg/d over 4 to 6 weeks (n=12), and then 3 additional cohorts receiving 30 or 90 mg/d over 6 to 7 weeks (n=14). A maximum tolerated dose was not reached. One dose-limiting toxicity (grade 3 gastroenteritis and vomiting with hyponatremia) occurred in each of 2 separate cohorts at 112 mg. Nausea/vomiting and facial paresthesia during infusion seemed to be GC4419 dose-related. Severe OM occurred through 60 Gy in 4 of 14 patients (29%) dosed for 6 to 7 weeks, with median duration of only 2.5 days.

CONCLUSIONS

The safety of GC4419 concurrently with chemoradiation for OCC was acceptable. Toxicities included nausea/vomiting and paresthesia. Doses of 30 and 90 mg/d administered for 7 weeks were selected for further study. In an exploratory analysis, severe OM seemed less frequent and briefer than expected.

Topical Clonazepam Solution for the Management of Burning Mouth Syndrome: A Retrospective Study

AIMS

To evaluate and compare the effectiveness of two concentrations of topical clonazepam solution in improving symptoms of burning mouth syndrome (BMS).

METHODS

A retrospective chart review was conducted of patients diagnosed with BMS and managed with topical clonazepam solution between 2008 and 2015. A 0.5-mg/mL solution was prescribed until 2012, when this was changed to a 0.1 mg/mL solution. Patients were instructed to swish with 5 mL for 5 minutes and spit two to four times daily. The efficacies of the two concentrations were compared using patient-reported outcome measures at the first follow-up, including the reported percentage of improvement in burning symptoms and the change in burning severity from baseline ranked on an 11-point numeric rating scale (NRS). Response to treatment was compared between the two concentrations using Wilcoxon rank sum test.

RESULTS

A total of 57 subjects were included, 32 in the 0.1-mg/mL cohort and 25 in the 0.5-mg/mL cohort, and evaluated at a median follow-up of 7 weeks. The median overall percentage improvement was 32.5% in the 0.1-mg/mL cohort and 75% in the 0.5-mg/mL cohort. The median reduction in NRS score was 0.5 points in the 0.1-mg/mL cohort and 6 points in the 0.5-mg/mL cohort. The use of either outcome measure revealed that the response to treatment with the 0.5-mg/mL solution was superior to that of the 0.1 mg/mL solution (P < .01).

CONCLUSION

These findings suggest that a 0.5-mg/mL topical clonazepam solution is effective in the management of BMS. Future randomized clinical trials are warranted.

Oral health status and risk of bacteremia following allogeneic hematopoietic cell transplantation

OBJECTIVES

The aim of this study was to evaluate the impact of oral health status on bacteremia risk in a cohort of patients with acute myeloid leukemia (AML) who underwent chemotherapy followed by myeloablative allogeneic hematopoietic cell transplantation (allo-HCT).

STUDY DESIGN

A retrospective study was conducted in patients with AML from 2007 to 2011. Oral health status was determined from a pre-allo-HCT dental evaluation. Positive blood cultures were recorded from AML induction to post-allo-HCT day +60. Organisms that caused bacteremia were classified as "of possible oral source" by a blinded microbiologist. Two-sided Fisher's exact test was used to compare the oral health status of the entire cohort with that of patients with blood cultures of potential oral source.

RESULTS

Pre-allo-HCT dental evaluations were completed in 91 (99%) of 92 patients. Of these 91 patients, 13 (14%) with dental pathology (13 of 13 [100%]) completed all required dental treatment before allo-HCT. Bacteremias occurred in 63 of 92 patients (68%), and 12 (19%) of 63 patients had positive blood cultures of potential oral source. Of these, 1 of 12 patients developed bacteremia during AML induction, and 11 of 12 developed bacteremia during allo-HCT.

CONCLUSIONS

Oral health status was not associated with risk of bacteremia of potential oral source either at AML induction or consolidation or at allo-HCT.

New Frontiers in the Pathobiology and Treatment of Cancer Regimen-Related Mucosal Injury

Mucositis is a common complication of chemotherapy, radiotherapy and targeted agents. It often affects compliance to anticancer therapies as it frequently causes schedule delays, interruptions or discontinuations of treatment. Moreover, the economic impact related to the management of mucositis is topical and several estimations of additional hospital costs due to this clinical condition have been recently reported. The ability to determine risk factors for mucositis, to early detect its onset, to assess correctly the degree of this toxicity and to plan its multidisciplinary management are all key elements to guarantee the quality of life of patients and to avoid useless dose reduction or interruption of treatment. The pathogenesis of mucositis is multifactorial and it is classily subdivided into oral and gastrointestinal mucositis according to its anatomic presentation. Treatment and patients’ related factors might help in predicting the frequency and the potential degree of symptoms onset. Here we discuss about clinical presentation and pathogenesis of mucositis in relation to different kinds of treatments. Moreover, we focus on therapeutic and prevention strategies, describing past and present management according to international guidelines and the most promising new data about agents potentially able to further improve the treatment of mucositis in the next future.

Genomic risk prediction of aromatase inhibitor-related arthralgias (AIA) in breast cancer (BC) patients using a novel analytical algorithm (NAA)

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Background: Many BC patients treated with aromatase inhibitors (AIs) develop AIA; 20% have symptoms severe enough to effect treatment compliance. Results of candidate gene studies to identify AIA risk are limited in scope. In this case-controlled study, we evaluated the potential of a NAA to predict AIA using germline single nucleotide polymorphism (SNP) data obtained prior to treatment initiation. Methods: Systematic chart review of 700 AI-treated patients with stage I-III BC between 2003-2012 identified asymptomatic patients (n = 39) and those with clinically significant AIA resulting in AI termination or therapy switch (n = 123). Germline DNA was obtained from peripheral blood cells and SNP genotyping performed using the Affymetrix UK BioBank Axiom Array to yield 695,277 SNPs. The identity of the cluster of SNPs that most closely defined AIA risk was discovered using an NAA that sequentially combined statistical filtering and a machine learning algorithm. NCBI PhenGenI and Ensemble databases were used to define gene attribution of the 200 most discriminating SNPs. Phenotype, pathway, and ontologic analyses assessed functional and mechanistic validity. Results: Cases and controls were similar in demographic characteristics. A cluster of 70 SNPs, correlated to 57 genes (accounting for linkage disequilibrium), was identified. This SNP group predicted AIA occurrence with a maximum accuracy of 75.93%. Strong associations with arthralgia, breast cancer, and estrogen phenotypes were seen in 19/57 genes (33%) and were functionally and ontologically consistent. Conclusions: Using a NAA, we identified a 70 SNP cluster that predicted AIA risk with fair accuracy. Phenotype, functional, and pathway analysis of attributed genes was consistent with clinical phenotypes. This study is the first to link a specific SNP/gene cluster to AIA risk independent of candidate gene bias. An ongoing prospective companion study will be used to validate and to expand upon results.

Dusquetide: Reduction in oral mucositis associated with enduring ancillary benefits in tumor resolution and decreased mortality in head and neck cancer patients

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Dusquetide was well-tolerated during treatment and throughout the 12-month follow-up.

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Dusquetide did not interfere with tumor treatment.

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Dusquetide treated groups had less mortality that placebo treated groups through the 12-month follow-up.

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Dusquetide treated groups had fewer “non-fungal” infections than placebo treated groups.

Innate immunity is a key component in the pathogenesis of oral mucositis, a universal toxicity of chemoradiation therapy (CRT). Dusquetide, a novel Innate Defense Regulator, has demonstrated both nonclinical and clinical efficacy in ameliorating severe oral mucositis (SOM). Long term follow-up studies from the Phase 2 clinical study evaluating dusquetide as a treatment for SOM in head and neck cancer (HNC) patients receiving CRT have now been completed. Extended analysis indicates that dusquetide therapy was well-tolerated and did not contribute to increased infection, tumor growth or mortality. Potential ancillary benefits of duquetide therapy were also identified.

The Use of Hyperbaric Oxygen for the Prevention and Management of Osteoradionecrosis of the Jaw: A Dana-Farber/Brigham and Women's Cancer Center Multidisciplinary Guideline

BACKGROUND

Osteoradionecrosis of the jaw (ORN) is an infrequent yet potentially devastating complication of radiation therapy to the head and neck region. Treatment options include antimicrobial therapy, local sequestrectomy, resection, and the use of hyperbaric oxygen (HBO). Published data on ORN are difficult to compare because of the lack of a universally accepted classification and staging system, and the literature on the use of HBO to either prevent or successfully manage ORN is controversial and inconclusive. Therefore, we aimed to establish a standard approach for using HBO at our institution.

MATERIALS AND METHODS

A literature search was conducted of articles published in the English language between January 1980 and January 2016. Retrieved articles were evaluated by two independent reviewers. Isolated case reports, abstracts, case series, review articles, and cohort studies without a control group were excluded; summary data were extracted from the remaining studies. A panel of experts from Head and Neck Oncology and Oral Medicine from the Dana-Farber Cancer Institute and Brigham and Women's Hospital reviewed the summary data and established multidisciplinary guidelines on the use of HBO for the prevention and management of ORN.

RESULTS

Seven studies were evaluated and reviewed by the multidisciplinary panel. There was no consistent evidence in support of HBO for either the prevention or management of ORN.

CONCLUSION

Based on the available evidence and expert opinion, routine use of HBO for the prevention or management of ORN is not recommended and is rarely used at our institution. The Oncologist 2017;22:343-350 IMPLICATIONS FOR PRACTICE: The Division of Head and Neck Oncology of Dana-Farber/Brigham and Women's Cancer Center does not recommend the routine use of HBO for the prevention or management of ORN. Adjunctive HBO may be considered for use on a case-by-case basis in patients considered to be at exceptionally high risk who have failed conservative therapy and subsequent surgical resection.

Dusquetide: A novel innate defense regulator demonstrating a significant and consistent reduction in the duration of oral mucositis in preclinical data and a randomized, placebo-controlled phase 2a clinical study

Dusquetide, a novel Innate Defense Regulator, modulates the innate immune system at a key convergence point in intracellular signaling pathways and has demonstrated activity in both reducing inflammation and increasing clearance of bacterial infection. Innate immunity has also been implicated in the pathogenesis of oral mucositis (OM), a universal toxicity of chemoradiation therapy (CRT). Testing the hypothesis that dusquetide can mitigate the development and duration of OM, preclinical studies have been completed and correlated with interim results from a Phase 2 clinical study in patients undergoing CRT for head and neck cancer. Dusquetide reduced the duration of OM in mouse and hamster models by approximately 50%, which was recapitulated by the 50% reduction of severe OM (SOM) in the Phase 2 trial. A reduction in the clinical rate of infection was also observed, consistent with previously reported preclinical studies. In aggregate, these results not only demonstrate the safety and efficacy of dusquetide in addressing this unmet medical need, but also provide proof of concept for the translation of dusquetide action between animal models and the human clinical setting, and further support the contention that innate immunity is an important driver for the initiation and continued impact of OM.

Impact of Microarray Preprocessing Techniques in Unraveling Biological Pathways

To better understand the impact of microarray preprocessing normalization techniques on the analysis of biological pathways in the prediction of chronic fatigue (CF) following radiation therapy, this study has compared the list of predictive genes found using the Robust Multiarray Averaging (RMA) and the Affymetrix MAS5 method, with the list that is obtained working with raw data (without any preprocessing). First, we modeled the spiked-in data set where differentially expressed genes were known and spiked-in at different known concentrations, showing that the precisions established by different gene ranking methods were higher than working with raw data. The results obtained from the spiked-in experiment were extrapolated to the CF data set to run learning and blind validation. RMA and MAS5 provided different sets of discriminatory genes that have a higher predictive accuracy in the learning phase, but lower predictive accuracy during the blind validation phase, suggesting that the genetic signatures generated using both preprocessing techniques cannot be generalizable. The pathways found using the raw data set better described what is a priori known for the CF disease. Besides, RMA produced more reliable pathways than MAS5. Understanding the strengths of these two preprocessing techniques in phenotype prediction is critical for precision medicine. Particularly, this article concludes that biological pathways might be better unraveled working with raw expression data. Moreover, the interpretation of the predictive gene profiles generated by RMA and MAS5 should be done with caution. This is an important conclusion with a high translational impact that should be confirmed in other disease data sets.

Pharmacotherapy for the management of cancer regimen-related oral mucositis

INTRODUCTION

Oral mucositis is a frequent and devastating toxicity secondary to cancer treatment, which may affect 20-40% of patients receiving conventional chemotherapy and 60-85% of patients undergoing hematopoietic stem cell transplantation. The pathobiology of mucositis includes a complex cascade of biologic events in which pro-inflammatory cytokines, ROS, second messengers, and the oral microbiome contribute to tissue damage of the oral mucosa. Management strategies to oral mucositis secondary to chemotherapy include preventative measures and therapeutic approaches.

AREA COVERED

A literature search of published animal and clinical studies was perform to review the epidemiology, pathophysiology and treatment options for cancer regimen-induced mucositis. We also discuss new data coming from recent pertinent clinical trials.

EXPERT OPINION

Mucositis is one of the most common debilitating toxicities secondary to cancer treatment and can adversely affect patients' quality of life. Epidemiological data for mucositis are often under-reported. Research efforts have shown that genetics plays a major role in the development of this toxicity. Although few therapeutic agents are available, several promising drugs are under investigations.