Combined Use Of Immunotherapy Research Articles

Immune checkpoint inhibitors and radiotherapy in gastrointestinal cancer treatment

Background. In recent decades, immunotherapy has become a topical area of research in the complex treatment of oncological diseases. A significant achievement in the immunotherapy of oncological diseases was the discovery of immune checkpoint proteins, which are effective inhibitors of the immune response. Immune checkpoint inhibitors (ICIs) have been approved for the treatment of certain gastrointestinal malignancies. However, the clinical efficacy of ICIs monotherapy remains low. To improve the outcome of treatment, numerous studies are conducted in which immunotherapy is combined with other standard methods of anticancer treatment. Radiation therapy (RT) may enhance the antitumor immune response when combined with ICIs and is worth considering when combined with immunotherapy. The effectiveness of the combined strategy is actively being investigated in clinical trials. Purpose – to highlight the latest achievements in the field of combined use of immunotherapy with ICIs and RT in malignant neoplasms of the gastrointestinal tract. Materials and methods. Data searches for the review were conducted using PubMed, Scopus, Google Scholar, and ClinicalTrials.gov databases. The data of works published in 2013-2023 were analyzed and systematized. Results and discussion. The rationality of the combination of RT and immunotherapy was substantiated. The results of the combined use of neoadjuvant chemoradiotherapy (CRT) and immunotherapy with ICIs in patients with resectable esophageal cancer and combined treatment in patients with advanced disease are analyzed. The clinical results of the use of ICIs in combination with RT or CRT in patients with gastric cancer and the combination of ICIs and RT in patients with hepatocellular carcinoma are presented. The clinical effects of adding ICIs to neoadjuvant RT or CRT in patients with locally advanced and borderline resectable pancreatic cancer and the results of trials of a combined strategy in patients with advanced disease are characterized. The clinical efficacy of the combined approach in locally advanced rectal cancer, which is a routine area of RT application, and in metastatic disease is reviewed. The results of small studies of combined treatment involving patients with metastatic colorectal cancer are presented. Conclusions. Over the past decade, research in the field of immunotherapy for gastrointestinal tumors has increased significantly. Based on the synergistic effects of radiation therapy and immune checkpoint inhibitors, the combination of these therapeutic approaches is increasingly being tested in gastrointestinal cancer to improve treatment outcomes. Published studies have shown encouraging results with satisfactory toxicity. However, most clinical trials are retrospective, non-comparative phase I/II trials and are limited to a small number of patients. The results of these studies can serve as a basis for conducting multicenter prospective studies with large sample sizes to confirm the effectiveness of combined therapy.

66 Early Experiences of the Use of Combination Immunotherapy for the Treatment of Malignant Mesothelioma from 2022–2023 – Real-World Evidence of 1-Year Data from a Single UK Tertiary Cancer Centre

66 Early Experiences of the Use of Combination Immunotherapy for the Treatment of Malignant Mesothelioma from 2022–2023 – Real-World Evidence of 1-Year Data from a Single UK Tertiary Cancer Centre

Safety and efficacy of zolbetuximab for CLDN18.2-positive gastric or gastroesophageal junction adenocarcinoma: A systematic review and meta-analysis of randomized controlled trials.

370 Background: Monoclonal antibody (Nivolumab, Trastuzumab, Bemarituzumab) with chemotherapy has shown benefit for patients with metastatic gastric or gastroesophageal junction (GEJ) adenocarcinoma. Zolbetuximab, a new monoclonal antibody against Claudin (CDLN) 18.2 has demonstrated interesting results in clinical trials, however, there is still a need to find a safe and effective first-line treatment, especially for epidermal growth factor receptor (HER) 2-negative patients. Therefore, we aimed to perform a meta-analysis exploring the use of combined immunotherapy (Zolbetuximab) and standard chemotherapy versus chemotherapy alone. Methods: We searched PubMed, Embase and Cochrane Central for randomized controlled trials (RCTs) comparing Zolbetuximab to chemotherapy alone in patients with CLDN18.2-positive gastric or GEJ adenocarcinoma. The outcomes evaluated were Overall Survival (OS), Progression Free-Survival (PFS), Objective Response Rate (ORR) and Treatment-Emergent Adverse Events (TEAE). We pooled hazard ratio (HR) for PFS and OS endpoints and risk ratio (RR) for ORR and TEAE, with 95% confidence intervals (CI). Statistical analyses were performed using R software version 4.3.1 with a random-effects model. I² analysis was used to assess heterogeneity. Adverse Events (AE) were graded according to the National Cancer Institute Common Terminology Criteria for AE. Results: From sixty-six studies, three were included, with a total of 1349 patients. 671 (49.7%) were part of the intervention group, 769 (57.0%) were male, 360 (26.7%) underwent prior gastrectomy and 1304 (96.7%) had a more than 70% CLDN18.2 cellular staining rate. Age range was 21-83 years. Treatment with Zolbetuximab was associated with significantly higher PFS (HR 0.64; CI 0.49-0.84; p = 0.0011; I² = 59.6%) and OS (HR 0.70; CI 0.59-0.84; p<0.0001; I² = 40.0%). TEAEs grade ≥ 3 (RR 1.09; CI 1.03-1.16; p = 0.0051; I² =0.0%) were greater for the intervention group. ORR and serious TEAE had no difference when compared with the control group. Most frequent AEs were nausea (34.6%), vomiting (30.2%) and decreased appetite (18.6%). Conclusions: In summary, the use of Zolbetuximab alongside standard chemotherapy reduces mortality and disease progression, although it might increase the risk for grade ≥ 3 treatment-emergent AEs.

Anti-Pythium insidiosum imunoterapia intradérmica em equinos: diagnóstico e terapia

ABSTRACT: Pythiosis is a life-threatening disease that affects various species and is prevalent in regions with high humidity. The ailment is increasingly reported globally, and in Brazil, it is an important cause of profound economic and health losses in equines. This study aimed to explore the potential of intradermal immunotherapy as both a diagnostic and therapeutic approach for pythiosis in horses from the Pantanal region of Mato Grosso, Brazil. The horses were divided into three groups: those never diagnosed with pythiosis or with lesions that could be mistaken for pythiosis (Group 1); previously infected but successfully treated horses (Group 2); and horses with a positive diagnosis for pythiosis that were under treatment (Group 3). An immunotherapeutic product (PitiumVac®) was administered intradermally. Injection site reaction and response to immunotherapy were assessed. The results indicated that intradermal immunotherapy could be a viable diagnostic and therapeutic tool, particularly in remote areas where traditional laboratory diagnosis methods are not readily accessible. The efficacy of intradermal administration was comparable to that of subcutaneous administration in treating pythiosis in horses, and the combined use of immunotherapy and triamcinolone acetonide yielded promising results for treating pythiosis in horses. However, further research is required to validate these findings. This study contributes to understanding and managing pythiosis more efficiently by providing a simple, cost-effective, and potentially efficient alternative approach to diagnosis and treatment.

Severe cardiac events induced by combination immunotherapy in patients with cancer: a meta-analysis.

The use of combined immunotherapy could increase non-severe and severe cardiac events in patients with cancer. To examine the occurrence of severe cardiac adverse events of combined immunotherapy compared to single immunotherapy, we analysed 4 electronic databases from inception to August 2021. We selected randomized controlled trials (RCTs) comparing combined versus single immunotherapy, for the treatment of melanoma, oesophagogastric cancer, renal cell carcinoma, and non-small cell lung cancer. Pre-defined combined immunotherapy included monoclonal antibodies against programmed cell death 1 (PD-1 inhibitors) plus against cytotoxic T lymphocyte antigen 4 (CTLA-4 inhibitors) or against programmed cell death ligand 1 (PD-L1 inhibitors) plus CTLA-4 inhibitors. The pooled risk ratios (RR) with their 95% confidence intervals (CI) were estimated using a random-effects model. Four RCTs involving 1581 patients were included, with a follow-up time between 18 and 39 months. The use of combined immunotherapy in comparison with single immunotherapy was not associated with an increased risk of severe cardiac adverse events: acute coronary syndromes (RR = 1.76, 95% CI: 0.29-10.83, very low certainty of evidence (CoE)), myocardial infarction (RR = 3.93, 95% CI: 0.44-35.39, very low CoE), heart failure (RR = 2.99, 95% CI: 0.61-14.79, very low CoE), and atrial fibrillation (RR = 2.26, 95% CI: 0.62-8.16, very low CoE). Our meta-analysis shows that the risk of severe cardiac adverse events with combined immunotherapy seems similar to single immunotherapy, but the evidence is very uncertain. Therefore, more RCTs with longer follow-ups and adequately powered to assess cardiac adverse events are needed to confirm these findings.

The emerging use of immunotherapy as a treatment option in metastatic renal cell carcinoma: Real-world evidence from a single UK tertiary cancer centre.

e16509 Background: The landscape of systemic anticancer therapy (SACT) options for the treatment of metastatic renal cell carcinoma (mRCC) has recently evolved following results from the CheckMate 214 trial in 2018 which demonstrated improved overall survival in patients with International mRCC Database Consortium (IMDC) intermediate- and poor-risk mRCC clear cell histological subtype receiving combination immunotherapy (Ipilimumab/Nivolumab) in the first-line setting compared to Sunitinib. This is in addition to other treatment options including: vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitors (TKIs) (e.g. Sunitinib, Pazopanib, Tivozanib, Cabozantinib, etc.), combination immunotherapy/TKI (e.g. Avelumab/Axitinib), VEGF/mammalian target of Rapamycin (mTOR) inhibitors (e.g. Lenvatinib/Everolimus) and single-agent immunotherapy (e.g. Nivolumab) in both first- and second-line settings. Methods: An audit of SACT prescribing practices in mRCC between 2019-2022 in a single UK tertiary cancer centre (Castle Hill Hospital, Hull, UK) was conducted as part of a national collaboration multi-centre UK audit looking into the real-world landscape and treatment choices in mRCC. Information was derived from the Somerset Cancer Registry and a dataset containing 87 patients with a coded diagnosis of ‘malignant neoplasm of kidney, except renal pelvis (CX64X)’ and ‘secondary malignant neoplasm of kidney & renal pelvis (C790)’ was generated. Results: Of the 81 patients included in the final analysis, 65% (n = 53) were male and 81% (n = 66) had a clear cell histological subtype. The main sites of metastases were lung (n = 58) and lymph nodes (n = 45). Most of the patients (n = 72) received either one or two lines of SACT. Of those with clear cell mRCC, 74% (n = 51/69) were classed as having IMDC intermediate- or poor-risk features with almost half (n = 34/69) receiving combination Ipilimumab/Nivolumab. Comparing overall survival (OS) and progression-free survival (PFS) to the published Kaplan-Meier curves in the CheckMate 214 trial, no significant differences in OS (p = 0.6) and PFS (p = 0.13) were observed, although there was an overall trend towards improved PFS in the first 6 months (82.4% vs 63.3%) in our local dataset. Conclusions: The results of our real-world evaluation of prescribing practices in mRCC favoured the use of combination immunotherapy in the first-line setting for the treatment of IMDC intermediate- and poor-risk clear cell mRCC with similar outcomes to the published data in the CheckMate 214 trial. The overall trend towards improved PFS in the first 6 months in our local dataset highlights the importance of patient selection when using immunotherapy.

Lysosomal lipid peroxidation mediates immunogenic cell death.

Cancer cells rely on lysosome-dependent degradation to recycle nutrients that serve their energetic and biosynthetic needs. Despite great interest in repurposing the antimalarial hydroxychloroquine as a lysosomal inhibitor in clinical oncology trials, the mechanisms by which hydroxychloroquine and other lysosomal inhibitors induce tumor-cell cytotoxicity remain unclear. In this issue of the JCI, Bhardwaj et al. demonstrate that DC661, a dimeric form of chloroquine that inhibits palmitoyl-protein thioesterase 1 (PPT1), promoted lysosomal lipid peroxidation, resulting in lysosomal membrane permeabilization and tumor cell death. Remarkably, this lysosomal cell death pathway elicited cell-intrinsic immunogenicity and promoted T lymphocyte-mediated tumor cell clearance. The findings provide the mechanistic foundation for the potential combined use of immunotherapy and lysosomal inhibition in clinical trials.

Durable Responses in Patients With Advanced Cholangiocarcinoma on Sequential Dual-agent Immunotherapy After Progressing on Single-agent Immunotherapy.

Objectives:Biliary tract tumors have a poor prognosis despite advancements in targeted therapies. More recent studies have started to investigate the use of combination immunotherapy in advanced biliary cancers. However, currently, there are no clinical trials investigating the use of dual-agent immunotherapy with ipilimumab and nivolumab as a sequential treatment after patients have progressed on single-agent immunotherapy. In this case series, we discussed 3 patients with advanced cholangiocarcinoma who have an objective response to dual-agent immunotherapy with ipilimumab and nivolumab after having disease progression on pembrolizumab and multiple other failed lines of treatment.Materials and Methods:A case series, including 3 patients treated at the University of California, Irvine Chao Family Comprehensive Cancer Center, was completed.Results:Although none of the 3 patients had microsatellite instability or high tumor-mutation burden and were not necessarily predicted to have a response to dual-agent immunotherapy, all 3 patients had an objective radiographic and/or tumor-marker response to a combination of ipilimumab and nivolumab.Conclusions:This case series serves as proof of the concept that sequential immunotherapy can be beneficial after progression on single-agent immunotherapy for patients with advanced cholangiocarcinoma. This study can also serve as the foundation to build further tests on the true effectiveness and ideal duration of sequential therapy with dual immunotherapy agents.

Acquired resistance for immune checkpoint inhibitors in cancer immunotherapy: challenges and prospects.

Drug resistance has become an obstacle to the further development of immunotherapy in clinical applications and experimental studies. In the current review, the acquired resistance to immunotherapy was examined. The mechanisms of acquired resistance were based on three aspects as follows: The change of the tumor functions, the upregulated expression of inhibitory immune checkpoint proteins, and the effects of the tumor microenvironment. The combined use of immunotherapy and other therapies is performed to delay acquired resistance. A comprehensive understanding of acquired drug resistance may provide ideas for solving this dilemma.

Current and future drug combination strategies based on programmed death-1/programmed death-ligand 1 inhibitors in non-small cell lung cancer.

In recent years, immune checkpoint inhibitors (ICIs) have made breakthroughs in the field of lung cancer and have become a focal point for research. Programmed death-1 (PD-1) or programmed death-ligand 1 (PD-L1) inhibitor monotherapy was the first to break the treatment pattern for non-small cell lung cancer (NSCLC). However, owing to the limited benefit of ICI monotherapy at the population level and its hyper-progressive phenomenon, it may not meet clinical needs. To expand the beneficial range of immunotherapy and improve its efficacy, several research strategies have adopted the use of combination immunotherapy. At present, multiple strategies, such as PD-1/PD-L1 inhibitors combined with chemotherapy, anti-angiogenic therapy, cytotoxic T-lymphocyte-associated protein 4 inhibitors, and radiotherapy, as well as combined treatment with new target drugs, have been evaluated for clinical practice. To further understand the current status and future development direction of immunotherapy, herein, we review the recent progress of ICI combination therapies for NSCLC.

IMMUNE EFFECTS OF STEREOTACTIC ABLATIVE RADIATION THERAPY IN PATIENTS WITH MALIGNANT TUMORS: LITERATURE REVIEW

The purpose of the study was to conduct a systematic analysis of the data available in the modern literature on the systemic (abscopal) effects in radiation therapy, which are mediated by immunological phenomena.Material and Methods.A structured search for articles published in peer-reviewed journals between January 2000 and February 2019 was conducted using MEDLINE database. The review included data from registered clinical trials at Clinicaltrials.gov, showing the results of the combined use of immunotherapy and radiation therapy.Results. There is an opinion that the systemic effect of radiotherapy is mediated by immunological phenomena. In connection with the recent data, there is a growing interest in the combined use of immunotherapy with radiation therapy in order to increase the efficacy of systemic therapy. However, the incidence of abscopal effects after standard radiation treatment is very low. In this regard, stereotactic ablative radiotherapy, due to its high immunogenic potential, low toxicity and short duration of the treatment, is apparently an attractive partner for immunotherapy in patients with metastatic disease.Conclusion. In view of the variety of the immunological effects of radiotherapy, further studies of the effect of radiation therapy on the immune system of cancer patients are needed, and the use of various combinations of immunotherapy and radiation therapy should be continued. All this, ultimately, will help improve the survival rates of cancer patients.

The Combined Use of SBRT and Immunotherapy-a Literature Review.

The purpose of this paper is to review all recent and relevant data regarding the combined use of immunotherapy (particularly immune checkpoint inhibitors) and radiotherapy. The use of radiotherapy, specifically stereotactic body radiation therapy (SBRT), and immunotherapy may be synergistic in the treatment of non-small cell lung cancer (NSCLC). There have been many preclinical and clinical studies that have shown that the combination of SBRT and immunotherapy is both safe and effective. In many cases, the benefits are greater than either SBRT or immunotherapy alone. Several ongoing trials are testing the combination of SBRT and immunotherapy for the treatment of all stages of NSCLC. The combined use of SBRT and immunotherapy is a promising new development. The techniques may synergistically work better than either alone.

Immunotherapy in Probable autoimmune encephalitis without detected autoantibody

Abstract Along with the rapidly expanding spectrum of autoimmune encephalitis (AE), probable AE with no detected autoantibody (AE-NoDab) has become a major category of AE. However, its clinical features, treatment, and prognosis were not demonstrated. In our institutional cohort of all consecutive patients with possible AE in 2012 – 2018, patients diagnosed with AE-NoDab were included in this study. AE-NoDab was subcategorized into limbic encephalitis (LE), acute disseminated encephalomyelitis (ADEM), and antibody negative probable AE (pAE). Patients’ clinical severity was assessed at every week for the first 12 weeks, at every month for the next 9 months, and then at every three months, using the modified Rankin scale (mRS) and the Clinical Assessment Scales in Autoimmune Encephalitis (CASE, score range 0–27) scores. Combination immunotherapy regimens used at each time point were categorized as steroid+immunoglobulin (SI), SI+Rituximab (anti CD-20 mAb, SIR), and SIR+ Tocilizumab (anti IL-6 mAb, SIRT). 136 patients (LE 52[38.2%], ADEM 14[10.3%], and pAE 70 [51.5%]) were followed-up for 39.0±19.6 (range 10–80) months. At last follow-up, 76 (55.9%) patients had favorable mRS outcomes (scores 0–2). Compared to 55 anti-NMDA receptor encephalitis patients, baseline severity was higher, use of immunotherapy was lower, and outcome was poorer in AE-NoDab. There was no difference in clinical characteristics, treatment, and outcomes among subcategories of AE-NoDab. In a linear mixed model analysis, using the SIRT regimen was more effective than conventional regimens such as SIR or SI in lowering CASE scores (both, P=0.001). Early diagnosis and use of combined immunotherapy consisting of SIRT is warranted to improve the poor outcomes of AE-NoDab.

Stereotactic radiotherapy combined with immunotherapy is safe and effective: Results from a phase I clinical trial.

9557 Background: There is growing evidence to suggest synergism between stereotactic ablative radiotherapy (SABR) and immunotherapy (IO) against metastatic melanoma. The optimal timing and dosing of SABR for this purpose has not been established. Here, we report results from a Phase I trial, finding the best outcomes with low dose SABR delivered late. Methods: Metastatic melanoma pts with at least two metastases received SABR to a single metastatic site. All pts had standard dose IO with anti-PD1 and/or anti-CTLA4. Following a standard 3+3 design, pts were escalated through three SABR doses (10Gy, 15Gy and 20Gy) delivered at three different time points (Cycle 1, 2, or 3 of IO). Dose limiting toxicity (DLT) were defined as Grade 3 or higher toxicity within 3 months of first treatment and assessed by an independent data safety monitoring committee (IDSMC). Logistic or cox regressions were used to assess the impact of SABR dose, timing and use of combination IO on toxicity, progression-free (PFS) and overall survival (OS) while controlling age, gender and baseline performance status. Results: Between April 2016 and August 2018, 24 pts were enrolled. The median age was 66 years and most were ECOG 0-1 (92%). The median follow-up was 10 months. Three pts (12.5%) developed DLTs (enterocolitis, hepatitis and liver function derangement). None occurred at SABR treated sites and all were in pts receiving 15Gy. DLTs were not associated with SABR timing (p = 0.44) or use of combination IO (p = 0.72). On this basis the IDSMC recommended stopping the trial and maximum tolerated SABR dose was defined at 10 Gy. The median PFS and OS were respectively 5.4m (95% CI 2.1m-NR) and 16.9m (95% CI 7.1m-NR). The median PFS for those receiving 10Gy was numerically higher than those receiving 15Gy (11.8m vs 2.6 m, p = 0.42). The only treatment related factor associated with improved PFS (HR = 0.14, p = 0.02) and OS (HR = 0.09, p = 0.04) was receiving SABR with Cycle 3. SABR dose (PFS p = 0.75, OS p = 0.67) and IO type (PFS p = 0.13, OS p = 0.06) were not significant. Conclusions: SABR combined with IO is generally safe overall. We found the optimal therapeutic index may be achieved with 10Gy delivered with the third cycle of IO; a strategy that warrants further testing. Clinical trial information: ACTRN12616001064493.

Combining the oncolytic peptide LTX-315 with doxorubicin demonstrates therapeutic potential in a triple-negative breast cancer model

BackgroundImmunochemotherapy, the combined use of immunotherapy and chemotherapy, has demonstrated great promise in several cancers. LTX-315 is an oncolytic peptide with potent immunomodulatory properties designed for the local treatment of solid tumors. By inducing rapid immunogenic cell death through the release of danger-associated molecular pattern molecules (DAMPs), LTX-315 is capable of reshaping the tumor microenvironment, turning “cold” tumors “hot” through a significant increase in tumor-infiltrating lymphocytes.MethodsWe investigated the potential of LTX-315 to be used in combination with standard-of-care chemotherapy (doxorubicin, brand name CAELYX®) against triple-negative breast cancer in an orthotopic 4 T1 mammary fat pad model. Tumor growth curves were compared using one-way ANOVA analysis of variance and Tukey’s multiple comparisons test, and animal survival curves were compared using the log-rank (Mantel-Cox) test. We considered p values ≤0.05 to indicate statistical significance.ResultsWe found that LTX-315 displayed a strong additive antitumoral effect when used in combination with CAELYX®, and induced immune-mediated changes in the tumor microenvironment, followed by complete regression in the majority of animals treated. Furthermore, imaging techniques and histological examination showed that the combination induced strong local necrosis, followed by an increase in the infiltration of CD4+ and CD8+ immune cells into the tumor parenchymal tissue.ConclusionsOur data demonstrate that LTX-315 is a promising combination partner with CAELYX® for the treatment of triple-negative breast cancer.

Myositis-specific autoantibodies, a cornerstone in immune-mediated necrotizing myopathy.

Over the past few years, myositis-specific autoantibodies played an increasing role in the inflammatory idiopathic myositis definition. They became the critical immunological marker for immune-mediated necrotizing myopathy diagnosis (IMNM) since the paradigm switch from histological to serological criteria. This review is focused on the key role of the anti-signal recognition particle (anti-SRP) and the anti-3-Hydroxy-3-MethylGlutaryl-Coenzyme A Reductase (anti-HMGCR) antibodies in immune-mediated necrotizing myopathy. Anti-SRP and anti-HMGCR antibodies are robust diagnostic tools in case of both the classical subacute form and the slowly progressive form of IMNM that may mimic muscular dystrophy. Anti-SRP and anti-HMGCR patients share clinical, biological and histological features with some antibody-associated specificity. Anti-SRP patients harbour more severe muscle weakness and atrophy with severe muscle damage on magnetic resonance imaging study. Approximately 10-20% of anti-SRP patients develop extramuscular symptoms, especially lung interstitial disease. Conversely, anti-HMGCR patients are often associated with statin exposure. In both cases, patients have a poor outcome with frequent relapse and the use of combined immunotherapy. Of note, various data suggest a direct pathogenic role of these antibodies reinforcing the interest in targeted therapeutic strategy.

Harnessing Metabolism with Radiation Therapy to Modulate Host Immunity in the Tumor Microenvironment

Host immunity affects response to immunotherapy (IO) and dictates T cell presence in the tumor microenvironment (TME). Analyses of patient IO response have not accounted for host metabolism, which contributes to chronic inflammation, directly affecting host immunity. As the use of combined IO and radiation therapy (RT) increases, targeting host metabolism is key. We have previously shown that caloric restriction (CR) can augment apoptotic effects of RT and set out to determine if CR could better prime the host for IO+RT therapies. Forty 12-week old female Balb/c mice were injected with syngeneic triple negative murine breast cancer (4T1) cells (5 x 104) and upon formation of a palpable tumor, were assigned to one of four treatment groups: ad lib (AL) fed, 8 Gy RT to the primary tumor (RT), 30% reduction in caloric intake (CR) or CR+RT. Primary tumor tissue was isolated and processed for analysis of immune markers. In the clinic, an IRB-approved feasibility trial using diet (25% CR for 10 weeks) concurrently with RT (60 Gy) for early-stage breast cancer patients was implemented. Serum was collected from patients before RT and after completion of RT and diet. Multiplex ELISA quantified cytokines in sera from trial patients and historical controls receiving RT alone. MicroRNA expression was evaluated in sera. Gene ontology analysis was done on microarray data as well as human sera. T-tests were used to compare expression levels and p ≤ 0.05 was significant. Preclinical and human data both implicated inflammation as a top pathway affected by RT and CR. Cytokine and microRNA data from the preclinical model led to further analysis of STAT3/5. RT alone increased STAT3 and STAT5 (2.5-fold; p=0.04 and 2.1-fold; p=0.03) in primary tumors, while CR alone decreased STAT3 and STAT5 (1.5-fold and 2.4-fold). This decrease remained with CR+RT. Co-expression of pSTAT3 and pSTAT5, which suggests Treg phenotype, was decreased in both the CR and CR+RT arms. Given that pSTAT3 targets miR-21, it was measured as a potential biomarker. MiR-21 was increased in the RT arm compared to AL (3.5-fold; p=0.003) and was decreased in both CR (2-fold; p=0.03) and CR+RT arms (2.5-fold; p=0.01). With respect to T cell function, IFNg was decreased in RT alone, but increased in both the CR and CR+RT treatment arms. Conversely, IL-10 expression was increased after RT alone, but decreased with CR and CR+RT. In human sera, analysis revealed increased memory T cell cytokines (IL-7, IL-15) in CR+RT patients as compared to RT alone and decreased Treg cytokines (IL-10, IL-23). We show that RT creates an immunosuppressive TME via upregulation of pSTAT3, pSTAT5 and IL-10, with a decrease in cytotoxic IFN-g, while CR creates a favorable antitumor TME. A similar cytokine signature seen in CR clinical samples corresponded to decreased levels of miR-21 in serum, making it a potential biomarker for host immunity in this setting. Future trials should explore the use of CR to improve efficacy of IO and RT+IO combination.

MS21.02 Chemotherapy through the 21st Century

MS21.02 Chemotherapy through the 21st Century

Differences between acute-onset chronic inflammatory demyelinating polyneuropathy and acute inflammatory demyelinating polyneuropathy in adult patients.

Acute inflammatory demyelinating polyneuropathy (AIDP) and acute-onset chronic inflammatory demyelinating polyneuropathy (A-CIDP) are conditions presenting overlapping clinical features during early stages (first 4 weeks), although the latter may progress after 8 weeks. The aim of this study was to identify predictive factors contributing to their differential diagnosis. Clinical records of adult patients with AIDP or A-CIDP diagnosed at our institution between January 2006 and July 2017 were retrospectively reviewed. Demographic characteristics, clinical manifestations, cerebrospinal-fluid (CSF) findings, treatment and clinical evolution were analyzed. Nerve conduction studies were performed in all patients with at least 12 months follow-up. A total of 91 patients were included (AIDP, n = 77; A-CIDP, n = 14). The median age was 55.5 years in patients with A-CIDP vs 43 years in AIDP (P = .07). The history of diabetes mellitus was more frequent in A-CIDP (29% vs 8%, P = .04). No significant differences between groups were observed with respect to: human immunodeficiency virus (HIV) status, presence of auto-immune disorder or oncologic disease. Cranial, motor and autonomic nerve involvement rates were similar in both groups. Patients in the A-CIDP group showed higher frequency of proprioceptive disturbances (83% vs 28%; P < .001), sensory ataxia (46% vs 16%; P = .01), and the use of combined immunotherapy with corticoids (29% vs 3%; P = .005). There were no significant differences in CSF findings, intensive care unit (ICU) admission, or mortality rates. During the first 8 weeks both entities are practically indistinguishable. Alterations in proprioception could suggest A-CIDP. Searching for markers that allow early differentiation could favor the onset of corticotherapy without delay.

Sequential, Multiple Assignment, Randomized Trial Designs in Immuno-oncology Research.

Clinical trials investigating immune checkpoint inhibitors have led to the approval of anti-CTLA-4 (cytotoxic T-lymphocyte antigen-4), anti-PD-1 (programmed death-1), and anti-PD-L1 (PD-ligand 1) drugs by the FDA for numerous tumor types. In the treatment of metastatic melanoma, combinations of checkpoint inhibitors are more effective than single-agent inhibitors, but combination immunotherapy is associated with increased frequency and severity of toxicity. There are questions about the use of combination immunotherapy or single-agent anti-PD-1 as initial therapy and the number of doses of either approach required to sustain a response. In this article, we describe a novel use of sequential, multiple assignment, randomized trial (SMART) design to evaluate immune checkpoint inhibitors to find treatment regimens that adapt within an individual based on intermediate response and lead to the longest overall survival. We provide a hypothetical example SMART design for BRAF wild-type metastatic melanoma as a framework for investigating immunotherapy treatment regimens. We compare implementing a SMART design to implementing multiple traditional randomized clinical trials. We illustrate the benefits of a SMART over traditional trial designs and acknowledge the complexity of a SMART. SMART designs may be an optimal way to find treatment strategies that yield durable response, longer survival, and lower toxicity. Clin Cancer Res; 24(4); 730-6. ©2017 AACR.