Selective immune suppression using interleukin-6 receptor inhibitors for management of immune-related adverse events

BACKGROUND

Management of immune-related adverse events (irAEs) is important as they cause treatment interruption or discontinuation, more often seen with combination immune checkpoint inhibitor (ICI) therapy. Here, we retrospectively evaluated the safety and effectiveness of anti-interleukin-6 receptor (anti-IL-6R) as therapy for irAEs.

METHODS

We performed a retrospective multicenter study evaluating patients diagnosed with de novo irAEs or flare of pre-existing autoimmune disease following ICI and were treated with anti-IL-6R. Our objectives were to assess the improvement of irAEs as well as the overall tumor response rate (ORR) before and after anti-IL-6R treatment.

RESULTS

We identified a total of 92 patients who received therapeutic anti-IL-6R antibodies (tocilizumab or sarilumab). Median age was 61 years, 63% were men, 69% received anti-programmed cell death protein-1 (PD-1) antibodies alone, and 26% patients were treated with the combination of anti-cytotoxic T lymphocyte antigen-4 and anti-PD-1 antibodies. Cancer types were primarily melanoma (46%), genitourinary cancer (35%), and lung cancer (8%). Indications for using anti-IL-6R antibodies included inflammatory arthritis (73%), hepatitis/cholangitis (7%), myositis/myocarditis/myasthenia gravis (5%), polymyalgia rheumatica (4%), and one patient each with autoimmune scleroderma, nephritis, colitis, pneumonitis and central nervous system vasculitis. Notably, 88% of patients had received corticosteroids, and 36% received other disease-modifying antirheumatic drugs (DMARDs) as first-line therapies, but without adequate improvement. After initiation of anti-IL-6R (as first-line or post-corticosteroids and DMARDs), 73% of patients showed resolution or change to ≤grade 1 of irAEs after a median of 2.0 months from initiation of anti-IL-6R therapy. Six patients (7%) stopped anti-IL-6R due to adverse events. Of 70 evaluable patients by RECIST (Response Evaluation Criteria in Solid Tumors) V.1.1 criteria; the ORR was 66% prior versus 66% after anti-IL-6R (95% CI, 54% to 77%), with 8% higher complete response rate. Of 34 evaluable patients with melanoma, the ORR was 56% prior and increased to 68% after anti-IL-6R (p=0.04).

CONCLUSION

Targeting IL-6R could be an effective approach to treat several irAE types without hindering antitumor immunity. This study supports ongoing clinical trials evaluating the safety and efficacy of tocilizumab (anti-IL-6R antibody) in combination with ICIs (NCT04940299, NCT03999749).

Intestinal toxicity to CTLA-4 blockade driven by IL-6 and myeloid infiltration

Immune checkpoint blockade (ICB) has revolutionized cancer treatment, yet quality of life and continuation of therapy can be constrained by immune-related adverse events (irAEs). Limited understanding of irAE mechanisms hampers development of approaches to mitigate their damage. To address this, we examined whether mice gained sensitivity to anti-CTLA-4 (αCTLA-4)-mediated toxicity upon disruption of gut homeostatic immunity. We found αCTLA-4 drove increased inflammation and colonic tissue damage in mice with genetic predisposition to intestinal inflammation, acute gastrointestinal infection, transplantation with a dysbiotic fecal microbiome, or dextran sodium sulfate administration. We identified an immune signature of αCTLA-4-mediated irAEs, including colonic neutrophil accumulation and systemic interleukin-6 (IL-6) release. IL-6 blockade combined with antibiotic treatment reduced intestinal damage and improved αCTLA-4 therapeutic efficacy in inflammation-prone mice. Intestinal immune signatures were validated in biopsies from patients with ICB colitis. Our work provides new preclinical models of αCTLA-4 intestinal irAEs, mechanistic insights into irAE development, and potential approaches to enhance ICB efficacy while mitigating irAEs.

Abstract 5545: Intestinal toxicity to CTLA-4 blockade driven by IL-6 and myeloid infiltration

Immunotherapies such as anti-CTLA-4 immune checkpoint blockade (ICB) have revolutionized cancer treatment, yet quality of life and continuation of therapy can be constrained by off-target tissue damage or immune-related adverse events (irAEs). At present, there is limited understanding of irAE mechanisms, hampering development of approaches to mitigate their damage. We addressed this problem by generating animal models of intestinal irAE. Our results show that disruption of homeostatic immunity by genetic predisposition to intestinal inflammation or acute gastrointestinal infection sensitizes mice to anti-CTLA-4-mediated intestinal toxicity. Inflammation-prone mice treated with anti-CTLA-4 showed neutrophil accumulation, systemic interleukin-6 (IL-6) release, and dysbiosis. Significantly, IL-6 blockade combined with antibiotic treatment improved anti-CTLA-4 therapeutic efficacy and reduced intestinal irAEs. Immune signatures were validated in biopsies from patients who developed colitis during ICB, supporting the utility of our models. This study provides new pre-clinical models, mechanistic insight into irAEs, and potential approaches to enhance ICB efficacy while mitigating irAEs.

Citation Format: Yifan Zhou, Yusra B. Medik, Bhakti Patel, Daniel B. Zamler, Sijie Chen, Thomas Chapman, Sarah Schneider, Rachel L. Babcock, Taylor T. Chrisikos, Laura M. Kahn, Allison M. Dyevoich, Elizabeth M. Park, Alexandria P. Cogdill, Daniel H. Johnson, Sarah B. Johnson, Khalida M. Wani, Debora A. Ledesma, Courtney W. Hudgens, Jingjing Wang, Md Abdul Wadud Khan, Aron Y. Joon, Weiyi Peng, Haiyan S. Li, Reetakshi Arora, Ximing Tang, Maria Gabriela Raso, Xuegong Zhang, Wai Chin Foo, Michael T. Tetzlaff, Gretchen E. Diehl, Karen Clise-Dwyer, Elizabeth M. Whitley, Matthew M. Gubin, James P. Allison, Patrick Hwu, Nadim J. Ajami, Adi Diab, Jennifer A. Wargo, Stephanie S. Watowich. Intestinal toxicity to CTLA-4 blockade driven by IL-6 and myeloid infiltration [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 5545.

Abstract 4177: Th17 inhibition with interleukin 6 blockade decouples immunotoxicity from tumor immunity

Durable remission rates with immune checkpoint inhibitor (ICI) monotherapy remain low. Combination ICI therapies could overcome immune resistance but are associated with higher rates of immune-related adverse events (irAEs). To elucidate the underlying irAE immunobiology, we profiled human intestinal tissue, enterocolitis (irEC), and tumor tissue from ICI-treated patients using NanoString PanCancer Immune Panel (NanoPCIP) and multiplex immunohistochemistry (mIHC); hypotheses generated from these translational results for potential irAE treatments were tested in parallel preclinical mouse model studies. In 23 patients identified with both normal intestinal and irEC tissue, we found genes encoding interleukin-6 (IL-6), Th17 differentiating cytokine, and neutrophil and monocyte chemotactic molecules were the highest significantly upregulated in irEC compared to patient-matched normal intestine. Using NanoPCIP cell scoring (23 patients) and mIHC (27 patients), Th17 cells were significantly higher in irEC than Th1 cells. T-cell subsets were similar between anti-CTLA-4 based regimen versus anti-PD-1monotherapy induced irEC, except Th17 memory cells were significantly higher CTLA-4i-induced irEC. We compared the degree of differential gene expression in irEC (normal intestine versus irEC) to the differential expression in tumors (baseline versus on-treatment tumors). The genes highest upregulated in irEC (including Th17 differentiating cytokines IL-6 and IL-1B) were not upregulated in responding tumors from patients receiving ICI. NanoPCIP Th17 cell score was significantly more upregulated than Th1 cells and neutrophils more upregulated than CD8 T cells in the irEC analysis, but not in the responding tumor analysis where IL-12 and CD8 cell score was significantly upregualted . Based on these discoveries, we used C57BL/6 and Balb/c mouse strains to address whether the antitumor effect of ICIs can be enhanced by IL-6 blockade while also improving irAEs. We found that IL-6 blockade + ICI was associated with improved tumor control and a higher density of CD4/CD8 effector T-cells, with reduced Th17, macrophages, and MDSCs compared to ICI alone. Furthermore, in the experimental autoimmune encephalomyelitis (EAE) mouse model, the pathogenesis of which is well documented to be Th17 mediated (Robinson et al., 2014), we demonstrated that combined IL-6 blockade and ICI enhanced tumor rejection while simultaneously mitigating EAE symptoms versus ICI alone. Based on the totality of the basic science, translational, and clinical data we hypothesize that IL-6 blockade combined with ICIs could de-couple autoimmunity from antitumor immunity. We are currently conducting a prospective phase 2 trials of combination ipilimumab (3mg/kg) + Nivolumab (1mg/kg) + Tocilizumab in patients with metastatic melanoma, EGFR mutant NSCLC, and urothelial carcinoma ( NCT04940299).

Citation Format: Daniel H. Johnson, Yared Hailemichael, Salah-Eddine Bentebibel, Noha Abdel-Wahab, Sungnam Cho, Wai C. Foo, Khalida Wani, Stephanie S. Watowich, Suhendan Ekmekcioglu, Adi Diab. Th17 inhibition with interleukin 6 blockade decouples immunotoxicity from tumor immunity [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 4177.

Interim safety and efficacy results from a phase 1 study of NT219 in adults with advanced solid tumors

3096

Background: NT219 is a small molecule, effecting IRS1/2 degradation and inhibiting STAT3 phosphorylation. IRS1/2 and STAT3 are major signaling junctions regulated by various oncogenes, altered during epithelial to mesenchymal transition (EMT) and drug resistance, and play an important role in the tumor and its microenvironment. A Phase 1/2 study (NCT04474470) includes a dose escalation of NT219 administered weekly for the treatment of relapsed and/or refractory cancer patients. Methods: In the dose escalation part of the study involving a conventional 3+3 design, patients with recurrent and/or metastatic solid tumors were administered intravenously with NT219 at 3, 6, 12 and 24mg/kg. Safety was assessed according to CTCAE v5 and anti-tumor activity was assessed by the investigators according to RECISTv1.1 using CT/MRI. The primary objectives of this part of the study are to evaluate safety, tolerability, PK and determine the recommended Phase 2 dose (RP2D). The study includes evaluation of potential biomarkers including measurements of STAT3, IRS1/2 phosphorylation, and TILs in biopsy specimens. Results: As of data cutoff date of February 8, 2022, a total of 13 patients were enrolled to 4 NT219 dose levels (3 - 24mg/kg) in the dose escalation phase, of which 11 were evaluable for dose limiting toxicity (DLT) determination, including 4 with colorectal cancer (CRC), 2 with pancreatic cancer, 2 with breast cancer, and one of each of the following cancers: gastroesophageal junction (GEJ), esophageal, appendiceal, papillary thyroid, and mesothelioma. Median number of prior treatment regimens for metastatic disease was 4 (2-11). Six Grade 3 adverse events (AEs) were observed, including alkaline phosphatase increase, aspartate aminotransferase increase, toxic encephalopathy, worsening back pain, abdominopelvic ascites, closed displaced fracture of right femoral neck, with the first 2 considered as possibly related to NT219. No Grade 4 AEs or treatment related deaths were reported. For the 11 evaluable patients, best overall response included one confirmed PR (GEJ patient, 5.5 months duration of response), and 3 SD (3 of 4 CRC patients; duration of 5.2, 4, and 2 months with ongoing follow up) with two patients awaiting follow up MRI/CT scans. As of the cutoff date, 9/11 patients that completed the DLT period are either on treatment or in follow up (range 1.1 to 14.7 months). Conclusions: Interim analysis of safety results obtained in 4 NT219 dose levels found NT219 to be well tolerated without DLTs in advanced cancer patients. The observed durable PR in a GEJ patient and SDs in 3 CRC patients are an encouraging initial signal of efficacy. Combination treatment of cetuximab with escalating NT219 doses in patients with recurrent/metastatic CRC and squamous cell carcinoma of the head and neck (SCCHN) has begun. An expansion cohort in patients with recurrent/metastatic SCCHN will be initiated at the conclusion of this part. Clinical trial information: NCT04474470.

Optimization of Voyager V1 (VV1) oncolytic virus systemic delivery in combination with cemiplimab and ipilimumab in patients with melanoma and non–small cell lung cancer (NSCLC)

TPS9595

Background: There is a need for novel immunotherapies to address the patient population that never or no longer responds to immune checkpoint inhibitors (CPI). VV1 is an oncolytic vesicular stomatitis virus engineered to express human interferon beta (IFNβ) to enhance cellular anti-tumor immune responses and tumor selectivity. Phase 1 studies demonstrated VV1 anti-tumor activity in several malignancies with or without a CPI. We are exploring ways to optimize VV1 efficacy in combination with cemiplimab, an anti-PD1 antibody approved for lung, basal and squamous cell skin cancers. Recent clinical data support a 5-fold higher dose of VV1 than was previously explored, and pre-clinical data show synergy between the oncolytic and an anti-CTLA4 antibody, in addition to cemiplimab, supporting exploration of a triplet. What was originally a five-arm study of intravenous (IV) VV1 in combination with IV cemiplimab has been amended to focus on 2 means of optimizing efficacy: use of a higher dose of VV1 and triplet combination in proof-of-concept populations. Methods: We are now enrolling pts with advanced melanoma (after progression on anti-PD1) and plan to include 1st-line NSCLC pts with PD-L1 expression ≥50%. The study is first exploring the preliminary anti-tumor activity, safety, and immunogenic activity of the combination of IV VV1 at a dose of 1.0 x 1011 TCID50 once on D1 followed by IV cemiplimab Q3W starting on D8, or the same regimen with an additional intratumoral injection of VV1 1.0 x 109 TCID50 once on D1 for pts with accessible lesions. Pts receive IV cemiplimab Q3W until confirmed disease progression or intolerable toxicity. Once at least 6 pts have been treated with acceptable safety across the 2 melanoma doublet cohorts using this higher dose of VV1, a 3rd melanoma cohort will open to add a single dose of ipilimumab 50 mg on D1 (all IV triplet). Once 6 melanoma pts have received the triplet safely, the 1st-line NSCLC cohort will open. All cohort decisions are guided by a Data Review Committee. Cohorts will be expanded based on a Simon 2-stage design using a type I error rate of 0.05 and power of 85%. Null ORR is 10% with a target of 35% for 2nd line melanoma and null ORR is 40% in 1st line NSCLC with a target of 70%. Each melanoma cohort will require a response in ≥2 of 10 pts in the 1st stage to add 11 more in the 2nd stage, while NSCLC will first need 5/9 evaluable pts to respond, then an additional 13 to complete the design. Response is assessed at week 7 then Q9W per RECIST v1.1. The study includes serial biopsies in ≥3/10 pts in Stage 1 of each of the IV melanoma cohorts (doublet and triplet therapy), all pts in Stage 2 of these IV melanoma cohorts, and all pts in both Stage 1 and Stage 2 of the IV/IT melanoma cohort, to permit a thorough investigation of the impact of the 3 immunotherapies under investigation. The study is currently ongoing in the USA. Clinical trial information: NCT04291105.

Interleukin-6 blockade abrogates immunotherapy toxicity and promotes tumor immunity

Immune checkpoint blockade (ICB) therapy frequently induces immune-related adverse events. To elucidate the underlying immunobiology, we performed a deep immune analysis of intestinal, colitis, and tumor tissue from ICB-treated patients with parallel studies in preclinical models. Expression of interleukin-6 (IL-6), neutrophil, and chemotactic markers was higher in colitis than in normal intestinal tissue; T helper 17 (Th17) cells were more prevalent in immune-related enterocolitis (irEC) than T helper 1 (Th1). Anti-cytotoxic T-lymphocyte-associated antigen 4 (anti-CTLA-4) induced stronger Th17 memory in colitis than anti-program death 1 (anti-PD-1). In murine models, IL-6 blockade associated with improved tumor control and a higher density of CD4+/CD8+ effector T cells, with reduced Th17, macrophages, and myeloid cells. In an experimental autoimmune encephalomyelitis (EAE) model with tumors, combined IL-6 blockade and ICB enhanced tumor rejection while simultaneously mitigating EAE symptoms versus ICB alone. IL-6 blockade with ICB could de-couple autoimmunity from antitumor immunity.

Tilsotolimod with Ipilimumab Drives Tumor Responses in Anti-PD-1 Refractory Melanoma

Many patients with advanced melanoma are resistant to immune checkpoint inhibition. In the ILLUMINATE-204 phase I/II trial, we assessed intratumoral tilsotolimod, an investigational Toll-like receptor 9 agonist, with systemic ipilimumab in patients with anti-PD-1- resistant advanced melanoma. In all patients, 48.4% experienced grade 3/4 treatment-emergent adverse events. The overall response rate at the recommended phase II dose of 8 mg was 22.4%, and an additional 49% of patients had stable disease. Responses in noninjected lesions and in patients expected to be resistant to ipilimumab monotherapy were observed. Rapid induction of a local IFNα gene signature, dendritic cell maturation and enhanced markers of antigen presentation, and T-cell clonal expansion correlated with clinical response. A phase III clinical trial with this combination (NCT03445533) is ongoing. SIGNIFICANCE: Despite recent developments in advanced melanoma therapies, most patients do not experience durable responses. Intratumoral tilsotolimod injection elicits a rapid, local type 1 IFN response and, in combination with ipilimumab, activates T cells to promote clinical activity, including in distant lesions and patients not expected to respond to ipilimumab alone.This article is highlighted in the In This Issue feature, p. 1861.

Timing of steroid initiation and response rates to immune checkpoint inhibitors in metastatic cancer

Background

Corticosteroids (CS) are the mainstay of immune-related adverse effect (irAE) management, as well as for other indications in cancer treatment. Previous studies evaluating whether CS affect immune checkpoint inhibitor (CPI) efficacy compared patients receiving CS versus no CS. However, there is a paucity of clinical data evaluating the timing of concomitant CS and CPI efficacy.

Methods

We retrospectively collected data from patients who received CS during CPI treatment at a single institution. Patients were in two cohorts based on timing of initiation of CS (≥2 months vs <2 months after initiating CPI). Patient characteristics, irAEs, cancer type, treatment type, treatment response/progression per RECIST V.1.1, and survival data were collected. Kaplan-Meier and Cox proportional hazard regression methods estimated HRs for the primary endpoint of progression-free survival (PFS) along with overall survival (OS).

Results

We identified 247 patients with metastatic cancer who received CS concurrently with CPIs. The median time on CS was 1.8 months. After adjusting for treatment type, tumor type, brain metastases, and irAEs, those treated with CS ≥2 months after starting CPI had a statistically significant longer PFS (HR=0.30, p<0.001), and OS (HR 0.34, p<0.0001) than those who received CS <2 months after starting CPI. Objective response rate (ORR) for patients on CS ≥2 months was 39.8%, versus ORR for patients <2 months was 14.7% (p value =<0.001)

Conclusion

Our results suggest that early use of CS during CPI treatment significantly hinders CPI efficacy. This data needs to be validated prospectively. Future studies should focus on the immune mechanisms by which CSs affect T-cell function early in the CPI treatment course.

A phase 1/2 study with open-label, dose escalation phase followed by single-arm expansion at the maximum tolerated dose to assess the safety, tolerability, pharmacokinetics, pharmacodynamics, and efficacy of NT219 injection alone and in combination with cetuximab in adults with advanced solid tumors and head and neck cancer

TPS3156

Background: NT219 is a small molecule, dual inhibitor of insulin receptor substrates (IRS) 1/2 and signal transducer and activator of transcription 3 (STAT3), effecting IRS1/2 degradation and inhibiting STAT3 phosphorylation. IRS1/2 and STAT3 are major signaling junctions regulated by various oncogenes, altered during epithelial to mesenchymal transition (EMT) and drug resistance, and play an important role in the tumor and its microenvironment. Patient derived xenograft (PDX) models have shown that inhibition of both IRS and STAT3 is essential to overcome targeted epidermal growth factor receptor inhibitor (EGFRi) resistance, and NT219 has demonstrated efficacy as monotherapy and in combination with immune oncology therapies. Particularly, both pathways have been found to be relevant in resistance to cetuximab in head and neck squamous cell carcinoma (HNSCC) PDX models. Methods: This phase 1/2 study (Clinical trial: NCT04474470) began in September 2020. The phase 1 component has a dose escalation arm of NT219 as a single agent at doses ranging between 3mg/kg and 50mg/kg in adult subjects with recurrent and/or metastatic solid tumors enrolled in sequential dose cohorts of 3 to 6 subjects, in a conventional 3+3 design aiming to establish the safety of single agent NT219. Following the conclusion of follow up on the third dose cohort, an additional dose-escalation arm of NT219 in combination with standard dose cetuximab will be opened in patients with recurrent and/or metastatic HNSCC and colorectal cancer, aiming to establish the safety of NT219 when combined with cetuximab. In the expansion phase, 29 patients will be enrolled at the recommended phase 2 dose in combination with standard dose cetuximab in patients with recurrent/metastatic HNSCC. The primary objectives of the trial are safety, tolerability, MTD, and RP2D and preliminary efficacy of NT219 alone and in combination with cetuximab. Measurements of STAT3 and IRS1/2 phosphorylation in biopsy specimens and TILs will be evaluated as potential biomarkers. NT219 provides a first-in-class treatment for patients with resistant neoplastic disease. The current trial will provide important data in patients with recurrent/metastatic cancers, particularly, HNSCC on the effects of the inhibition of STAT3 and IRS1/2 pathways as a novel therapeutic approach. Clinical trial information: NCT04474470.

Impact of body mass index on survival rates in patients receiving immune checkpoint inhibitors

e15108

Background: Obesity is associated with 13 different cancer types, accounting for 40% of all cancers1. A few studies have linked a higher Body Mass Index (BMI) with longer Progression Free Survival (PFS) and Overall Survival (OS) from immune checkpoint inhibitors (CPI)s in patients with advanced melanoma, non-small cell lung cancer, and renal cell carcinoma2,3,4. Our study evaluates CPI efficacy in patients with multiple tumor types in relation to Body Mass Index (BMI). Methods: We retrospectively collected data from patients treated with CPIs alone who also received steroids during their treatment from a single institution. This data included demographics such as age, sex, and BMI. Response and progression were defined per RECIST v1.1. The association of BMI and PFS was assessed by exact chi-square test. Kaplan Meier and Cox proportional hazard regression methods were used to estimate the survival probability and hazard ratios. Results: We identified a total of 129 overweight or obese patients (49%) with stage IV cancer who received CPI therapy. CDC guidelines define overweight as BMI > 25 and obese as BMI > 30. There was a significant relationship between PFS and BMI. Median PFS for those overweight was 287 days and 479 days for obese. Those with BMI 18.5-25 (normal), median PFS was 128 days and 103 days for those underweight (BMI < 18.5), (p = .0024). There was also a significant relationship between OS and BMI. Median OS for those obese was 751 days, for those overweight was 462 days. Median OS for those normal weight was 281 days and those underweight was 273 days (p = .0005). Obese patients had a 48% reduced risk of progression of disease/death as compared to those who had normal BMI (Hazard Ratio 0.52, p = .019). Overweight had a 31.5% relative risk reduction (HR 0.685, p = .05). Overall Response Rate was not significant between the two groups but there was a strong trend (p = .087). Conclusions: Higher BMI was associated with improved PFS and OS in patients with metastatic cancer across 20 different tumor types. Further investigation into the immune mechanisms behind this may lead to improvement in CPI efficacy for all patients.

Cumulative steroid doses and response rates to immune checkpoint inhibitors in metastatic cancer

e15133

Background: Steroids are the mainstay of immune-related adverse effect (irAE) management, as well as for other indications in cancer treatment. Previous studies evaluating whether steroids have an effect on immune checkpoint inhibitor (CPI) efficacy compared patients receiving steroids vs. no steroids. This comparison may be confounded by different rates of irAEs and a known association of irAEs with higher response rates to CPIs. There is a paucity of CPI efficacy data in relation to the total dose of concomitant steroids. Methods: We retrospectively collected data from patients treated with CPIs alone, who received steroids during their CPI treatment at a single institution. IrAEs were defined using the CTCAEv5 criteria. Response rate (RR) and progression were defined per RECIST v1.1. Kaplan Meier and Cox proportional hazard regression methods were used to estimate the survival probability and hazard ratios (HR). Results: We identified 260 patients with stage IV cancer who received steroids concurrently with CPI treatment. A total of 111 patients (42.7%) received ≥1000mg prednisone equivalence during the course of their CPI treatment, and the remaining 149 patients (57.3%) received < 1000mg PED. There was no difference in progression free survival (PFS) between the two cohorts [HR of 0.923 for < 1000 mg PED group; p = 0.6016] or in overall survival (OS) [0.854 for < 1000 mg PED group, p = 0.3308]. Median PFS for the < 1000mg group was 5.9 months (mo), vs 6.3 mo in the ≥1000mg group. Median OS for the < 1000mg group was 15.76 mo, vs 11.53 mo in the ≥1000mg group. The RR was numerically higher in the prednisone < 1000mg cohort at 29.53% vs 20.72% in the ≥1000mg cohort, however not statistically significant (p = 0.1082). Basic characteristics including sex, race, tumor type, and smoking status, were similar between the two groups. There was a statistically significant difference in BMI distribution and steroid indication (irAE indication higher in >1000 mg PED cohort than non-irAE) between the two groups. Conclusions: PFS, OS, and RR were not different between patients who received >1000mg vs. < 1000mg PED during CPI therapy. These data suggest that even high doses and protracted courses of corticosteroids may not hinder CPI efficacy. However, differences in our primary endpoint PFS may be confounded by difference in BMI and rates of irAEs between each cohort, which are both known to be associated with improved CPI efficacy. Further analyses to account for these differences along with how timing of steroid initiation affects CPI-efficacy will be completed by time of presentation.

Immune checkpoint inhibitor related myasthenia gravis: single center experience and systematic review of the literature

BACKGROUND

Myasthenia gravis (MG) is a rare but life-threatening adverse event of immune checkpoint inhibitors (ICI). Given the limited evidence, data from a large cohort of patients is needed to aid in recognition and management of this fatal complication.

METHODS

We reviewed our institutional databases to identify patients who had cancer and MG in the setting of ICI. We systematically reviewed the literature through August 2018 to identify all similar reported patients. We collected data on clinical and diagnostic features, management, and outcomes of these cases.

RESULTS

Sixty-five patients were identified. Median age was 73 years; 42 (65%) were males, 31 (48%) had metastatic melanoma, and 13 (20%) had a preexisting MG before ICI initiation. Most patients received anti-PD-1 (82%). Sixty-three patients (97%) developed ICI-related MG (new onset or disease flare) after a median of 4 weeks (1 to 16 weeks) of ICI initiation. Twenty-four patients (37%) experienced concurrent myositis, and respiratory failure occurred in 29 (45%). ICI was discontinued in 61 patients (97%). Death was reported in 24 patients (38%); 15 (23%) due to MG complication. A better outcome was observed in patients who received intravenous immunoglobulin (IVIG) or plasmapheresis (PLEX) as first-line therapy than in those who received steroids alone (95% vs 63% improvement of MG symptoms, p = 0.011).

CONCLUSIONS

MG is a life-threatening adverse event of acute onset and rapid progression after ICI initiation. Early use of IVIG or PLEX, regardless of initial symptoms severity, may lead to better outcomes than steroids alone. Our data suggest the need to reassess the current recommendations for management of ICI-related MG until prospective longitudinal studies are conducted to establish the ideal management approach for these patients.

Phase II trial of nab-paclitaxel (ABI) and ipilimumab (ipi) in patients with treatment naïve metastatic melanoma

9554

Background: Conventional chemotherapies possess intrinsic immune-regulatory properties. Some taxanes for instance, stimulate antigen presentation and impair regulatory T-cells while leaving effector T cells intact. Combining chemotherapies with immune checkpoint inhibitor at carefully designed dosing regimens may increase tumor cell susceptibility to immune-mediated death and thus enhance therapeutic efficacy. We describe the safety and updated efficacy of ABI and ipi in patients with metastatic melanoma. Methods: In this open-label, single center, phase II trial, ABI was administered to treatment naïve metastatic patients at 150mg/m2 on days 1,8 and 15 every 4 weeks and ipi at 3mg/kg on day 1 every 3 weeks limited to 4 cycles until disease progression or unacceptable toxicity. Endpoints included ORR, OS and safety. Results: 18 of 21 enrollees between 6/2013 and 6/2015 with Stage IV melanoma (M1c: 56%, M1b: 33%, M1a: 11%) were included in the analysis. The median age was 57 years old (33-69) and 67% were men. 44% harbored BRAF mutations. Median duration of treatment was 9 weeks (5 to 17). Median follow-up time for OS analysis was 22.5 months (2 to 52 months). 12 and 24 month OS were 77.8% and 60.6% respectively with median not yet reached. The ORR by by irRECIST was 27.8%. Grade 3 adverse events were reported in 50% of patients, the most common being neutropenia. 17% of patients had grade 3 immune-related adverse events, the most common being hypophysitis and colitis. Immune analysis showed absolute lymphocyte count was significantly elevated post treatment compared with pre-treatment (p = 0.024). In addition, deep immune analysis of peripheral blood samples and tumor tissue including nanostring, gene expression and TCR sequencing will be assessed and reported. Conclusions: The combination of ipi and ABI in this small study demonstrates acceptable safety, tolerability and clinical activity. ABI may contribute to tumor cytoreduction and enhance antitumor clinical response of ipi without impactful immunosuppression. This data together with further immune analysis may provide rationale to design prospective chemo-immunotherapy regimens and treatments for metastatic melanoma and other solid tumors. Clinical trial information: NCT01827111.

Interleukin-6 is potential target to de-couple checkpoint inhibitor-induced colitis from antitumor immunity

2616

Background: A deep understanding of the immunobiology of checkpoint inhibitor (CPI) induced immune related toxicities, such as immune related enterocolitis (irEC), and how these compare to the immune signatures in tumors could lead to the development of strategies that de-couple autoimmunity from anti-tumor immunity. Methods: Total RNA from patient-matched irEC and normal colon FFPE tissue from patients [n = 12] receiving CPIs were profiled with the 770 gene NanoString nCounter PanCancer Immune Profiling Panel (NanoPCIP). The mean fold change in gene expression from normal vs. irEC inflamed colonic tissue and baseline vs. on-treatment tumor samples from patients responding or non-responding to ipilimumab based therapy were analyzed. C57BL/6 mice with B16.BL6 melanoma tumors were treated with systemic anti-IL-6 + anti-CTLA-4 vs. anti-CTLA4 alone vs. placebo and tumor size was measured. Results: In patients with irEC, the highest significantly upregulated differentially expressed gene (DEG) in inflamed colon tissue encoded for IL-6 (Fold change +24.1). None of the significant and highest upregulated DEGs in the colitis, including IL-6, were significantly upregulated in responding tumors. Interestingly, IL-6 was also the highest upregulated DEG in non-responding tumors numerically. When comparing mean fold changes across these analyses, the gene with the largest difference in upregulatation between colitis and responding tumors was IL-6; the other highest upregulated genes in colitis encoded for neutrophil and monocyte chemotactic molecules. In our mouse models, the addition of IL-6 blockade to anti-CTLA-4 therapy significantly improved tumor shrinkage compared to anti-CTLA-4 alone. Conclusions: Our data demonstrates that IL-6-mediated inflammation may be more prevalent in irEC and tumors not responding to CPIs than in tumors responding, and blocking IL-6 enhances CPI anti-melanoma activity. Targeting IL-6 may ameliorate irEC without hindering anti-tumor immunity.

Checkpoint inhibitor therapy for cancer in solid organ transplantation recipients: an institutional experience and a systematic review of the literature

Background

Checkpoint inhibitors (CPIs) have revolutionized the treatment of cancer, but their use remains limited by off-target inflammatory and immune-related adverse events. Solid organ transplantation (SOT) recipients have been excluded from clinical trials owing to concerns about alloimmunity, organ rejection, and immunosuppressive therapy. Thus, we conducted a retrospective study and literature review to evaluate the safety of CPIs in patients with cancer and prior SOT.

Methods

Data were collected from the medical records of patients with cancer and prior SOT who received CPIs at The University of Texas MD Anderson Cancer Center from January 1, 2004, through March 31, 2018. Additionally, we systematically reviewed five databases through April 2018 to identify studies reporting CPIs to treat cancer in SOT recipients. We evaluated the safety of CPIs in terms of alloimmunity, immune-related adverse events, and mortality. We also evaluated tumor response to CPIs.

Results

Thirty-nine patients with allograft transplantation were identified. The median age was 63 years (range 14–79 years), 74% were male, 62% had metastatic melanoma, 77% received anti-PD-1 agents, and 59% had prior renal transplantation, 28% hepatic transplantation, and 13% cardiac transplantation. Median time to CPI initiation after SOT was 9 years (range 0.92–32 years). Allograft rejection occurred in 41% of patients (11/23 renal, 4/11 hepatic, and 1/5 cardiac transplantations), at similar rates for anti-CTLA-4 and anti-PD-1 therapy. The median time to rejection was 21 days (95% confidence interval 19.3–22.8 days). There were no associations between time since SOT and frequency, timing, or type of rejection. Overall, 31% of patients permanently discontinued CPIs because of allograft rejection. Graft loss occurred in 81%, and death was reported in 46%. Of the 12 patients with transplantation biopsies, nine (75%) had acute rejection, and five of these rejections were T cell-mediated. In melanoma patients, 36% responded to CPIs.

Conclusions

SOT recipients had a high allograft rejection rate that was observed shortly after CPI initiation, with high mortality rates. Further studies are needed to optimize the anticancer treatment approach in these patients.

Electronic supplementary material

The online version of this article (10.1186/s40425-019-0585-1) contains supplementary material, which is available to authorized users.

Infliximab associated with faster symptom resolution compared with corticosteroids alone for the management of immune-related enterocolitis

BACKGROUND

Immune-related enterocolitis (irEC) is the most common serious complication from checkpoint inhibitors (CPIs). The current front-line treatment for irEC, high-dose corticosteroids (CS), have significant side effects and prolonged therapy may reduce CPI-anti-tumor activity. Early addition of TNF-α inhibitors such as infliximab (IFX) may expedite symptom resolution and shorten CS duration. Thus, we conducted the first retrospective study, to our knowledge, evaluating symptom resolution in patients with irEC treated with and without IFX.

METHODS

Data were collected from the medical records of patients diagnosed with irEC. The primary endpoint was time to symptom resolution for irEC for cases managed with IFX plus CS (IFX group) versus CS alone (CS group). Duration of CS, overall survival (OS), and time to treatment failure (TTF) were secondary endpoints.

RESULTS

Among 75 patients with irEC, 52% received CS alone, and 48% received IFX. Despite higher grade colitis in the IFX group (grade 3/4: 86% vs. 34%; p < 0.001), median times to diarrhea resolution (3 vs. 9 days; p < 0.001) and to steroid titration (4 vs. 13 days; p < 0.001) were shorter in the IFX group than in the CS group without a negative impact on TTF or OS. Total steroid duration (median 35 vs. 51 days; p = 0.150) was numerically lower in the IFX group.

CONCLUSIONS

Despite higher incidence of grade 3/4 colitis, IFX added to CS for the treatment of patients with irEC was associated with a significantly shorter time to symptom resolution. The data suggest that early introduction of IFX should be considered for patients with irEC until definitive prospective clinical trials are conducted.

Role of Franzen Needle Aspiration Biopsy in Carcinoma of the Prostate

A retrospective study is reported of all Franzen fine-needle aspiration cytology undertaken at Southmead Hospital between January 1978 and December 1981. A total of 1043 aspirates were examined from 753 patients. The diagnosis of carcinoma of the prostate was missed in 2 patients. Twenty-one patients with cytologicallyproven carcinoma in histologically-benign prostates were detected, and the role of the Franzen needle in the diagnosis of early prostatic cancer is discussed. Of the 218 patients proceeding to prostatectomy, there were 91 patients with carcinoma and in 65 (72%) the cytological and histological grading was identical. A significant disparity occurred in 8 cases and the reasons are discussed.

Impact of thoracic radiotherapy timing in limited-stage small-cell lung cancer: usefulness of the individual patient data meta-analysis

BACKGROUND

Chemotherapy (CT) combined with radiotherapy is the standard treatment of 'limited-stage' small-cell lung cancer. However, controversy persists over the optimal timing of thoracic radiotherapy and CT.

MATERIALS AND METHODS

We carried out a meta-analysis of individual patient data in randomized trials comparing earlier versus later radiotherapy, or shorter versus longer radiotherapy duration, as defined in each trial. We combined the results from trials using the stratified log-rank test to calculate pooled hazard ratios (HRs). The primary outcome was overall survival.

RESULTS

Twelve trials with 2668 patients were eligible. Data from nine trials comprising 2305 patients were available for analysis. The median follow-up was 10 years. When all trials were analysed together, 'earlier or shorter' versus 'later or longer' thoracic radiotherapy did not affect overall survival. However, the HR for overall survival was significantly in favour of 'earlier or shorter' radiotherapy among trials with a similar proportion of patients who were compliant with CT (defined as having received 100% or more of the planned CT cycles) in both arms (HR 0.79, 95% CI 0.69-0.91), and in favour of 'later or longer' radiotherapy among trials with different rates of CT compliance (HR 1.19, 1.05-1.34, interaction test, P < 0.0001). The absolute gain between 'earlier or shorter' versus 'later or longer' thoracic radiotherapy in 5-year overall survival for similar and for different CT compliance trials was 7.7% (95% CI 2.6-12.8%) and -2.2% (-5.8% to 1.4%), respectively. However, 'earlier or shorter' thoracic radiotherapy was associated with a higher incidence of severe acute oesophagitis than 'later or longer' radiotherapy.

CONCLUSION

'Earlier or shorter' delivery of thoracic radiotherapy with planned CT significantly improves 5-year overall survival at the expense of more acute toxicity, especially oesophagitis.

Clinical Case of the Month: A 64 Year-Old Woman Presenting With Fever, Confusion, Ophthalmoplegia and Pneumonia

Legionella pneumophila is a major cause of atypical community-acquired pneumonia, which is commonly severe enough to require hospitalization. Though primarily a respiratory infection, Legionellosis involves the central nervous system (CNS) in up to 50% of patients, and diagnosis can be obscured by the absence of obvious respiratory symptomatology. A reversible diffuse encephalopathy is the most common neurologic complication, but focal CNS involvement can sometimes be the initial presentation. We report a case of a woman infected with Legionella pneumophila presenting with vague symptomatology and focal neurologic findings. This report highlights the challenges of early recognition of Legionella infection when neurologic symptoms predominate.

Phenome-wide Association Study Relating Pretreatment Laboratory Parameters With Human Genetic Variants in AIDS Clinical Trials Group Protocols

Background.  Phenome-Wide Association Studies (PheWAS) identify genetic associations across multiple phenotypes. Clinical trials offer opportunities for PheWAS to identify pharmacogenomic associations. We describe the first PheWAS to use genome-wide genotypic data and to utilize human immunodeficiency virus (HIV) clinical trials data. As proof-of-concept, we focused on baseline laboratory phenotypes from antiretroviral therapy-naive individuals. Methods.  Data from 4 AIDS Clinical Trials Group (ACTG) studies were split into 2 datasets: Dataset I (1181 individuals from protocol A5202) and Dataset II (1366 from protocols A5095, ACTG 384, and A5142). Final analyses involved 2547 individuals and 5 954 294 imputed polymorphisms. We calculated comprehensive associations between these polymorphisms and 27 baseline laboratory phenotypes. Results.  A total of 10 584 (0.17%) polymorphisms had associations with P < .01 in both datasets and with the same direction of association. Twenty polymorphisms replicated associations with identical or related phenotypes reported in the Catalog of Published Genome-Wide Association Studies, including several not previously reported in HIV-positive cohorts. We also identified several possibly novel associations. Conclusions.  These analyses define PheWAS properties and principles with baseline laboratory data from HIV clinical trials. This approach may be useful for evaluating on-treatment HIV clinical trials data for associations with various clinical phenotypes.

Nuclear imaging: a powerful novel approach for tuberculosis

Nearly 20 years after the World Health Organization declared tuberculosis (TB) a global public health emergency, TB still remains a major global threat with 8.6 million new cases and 1.3 million deaths annually. Mycobacterium tuberculosis adapts to a quiescent physiological state, and is notable for complex interaction with the host, producing poorly-understood disease states ranging from latent infection to fully active disease. Of the approximately 2.5 billion people latently infected with M. tuberculosis, many will develop reactivation disease (relapse), years after the initial infection. While progress has been made on some fronts, the alarming spread of multidrug-resistant, extensively drug-resistant, and more recently totally-drug resistant strains is of grave concern. New tools are urgently needed for rapidly diagnosing TB, monitoring TB treatments and to allow unique insights into disease pathogenesis. Nuclear bioimaging is a powerful, noninvasive tool that can rapidly provide three-dimensional views of disease processes deep within the body and conduct noninvasive longitudinal assessments of the same patient. In this review, we discuss the application of nuclear bioimaging to TB, including the current state of the field, considerations for radioprobe development, study of TB drug pharmacokinetics in infected tissues, and areas of research and clinical needs that could be addressed by nuclear bioimaging. These technologies are an emerging field of research, overcome several fundamental limitations of current tools, and will have a broad impact on both basic research and patient care. Beyond diagnosis and monitoring disease, these technologies will also allow unique insights into understanding disease pathogenesis; and expedite bench-to-bedside translation of new therapeutics. Finally, since molecular imaging is readily available for humans, validated tracers will become valuable tools for clinical applications.

Genome-wide association study of peripheral neuropathy with D-drug-containing regimens in AIDS Clinical Trials Group protocol 384

Stavudine (d4T) was, until recently, one of the most widely prescribed antiretroviral drugs worldwide. While there has been a major shift away from d4T use in resource-limited countries, a large number of patients have previously received (or continue to receive) d4T, and many have developed peripheral neuropathy. The identification of genetic predictors of increased risk might suggest novel therapeutic targets for such patients. In AIDS Clinical Trials Group protocol 384, antiretroviral-naïve patients were randomized to d4T/didanosine (ddI)- or zidovudine/lamivudine-containing regimens. Data from d4T/ddI recipients were analyzed for genome-wide associations (approximately 1 million genetic loci) with new onset distal sensory peripheral neuropathy. Analyses involved 254 patients (49 % White, 34 % Black, 17 % Hispanic), comprising 90 peripheral neuropathy cases (32 grade 1, 35 grade 2, 23 grade 3) and 164 controls. After correcting for multiple comparisons, no polymorphism was consistently associated with neuropathy among all patients, among White, Black, and Hispanic patients analyzed separately, both in genome-wide analyses (threshold, P < 5.0 × 10⁻⁸) and focused on 46 neuropathy-associated genes (threshold, P < 3.5 × 10⁻⁵). In the latter analyses, the lowest P values were in KIF1A among Whites (rs10199388, P = 8.4 × 10⁻⁴), in LITAF among Blacks (rs13333308, P = 6.0 × 10⁻⁶), and in NEFL among Hispanics (rs17763685, P = 5.6 × 10⁻⁶). Susceptibility to d4T/ddI-associated neuropathy is not explained by a single genetic variant with a marked effect.

Genetic and non-genetic determinants of raltegravir penetration into cerebrospinal fluid: a single arm pharmacokinetic study

Background

Antiretroviral drugs vary in their central nervous system penetration, with better penetration possibly conferring neurocognitive benefit during human immunodeficiency virus (HIV) therapy. The efflux transporter gene ABCB1 is expressed in the blood-brain barrier, and an ABCB1 variant (3435C→T) has been reported to affect ABCB1 expression. The integrase inhibitor raltegravir is a substrate for ABCB1. We examined whether ABCB1 3435C→T affects raltegravir disposition into cerebrospinal fluid (CSF), and explored associations with polymorphisms in other membrane transporter genes expressed in the blood-brain barrier.

Methods

Forty healthy, HIV-negative adults of European descent (20 homozygous for ABCB1 3435 C/C, 20 homozygous for 3435 T/T, each group divided equally between males and females) were given raltegravir 400 mg twice daily for 7 days. With the final dose, plasma was collected for pharmacokinetic analysis at 9 timepoints over 12 hours, and CSF collected 4 hours post dose.

Results

The 4-hour CSF concentration correlated more strongly with 2-hour (r²=0.76, P=1.12x10^-11) than 4-hour (r²=0.47, P=6.89x10^-6) single timepoint plasma concentration, and correlated strongly with partial plasma area-under-the-curve values (AUC_0-4h r²=0.86, P=5.15x10^-16). There was no significant association between ABCB1 3435C→T and ratios of CSF-to-plasma AUC or concentration (p>0.05 for each comparison). In exploratory analyses, CSF-to-plasma ratios were not associated with 276 polymorphisms across 16 membrane transporter genes.

Conclusions

Among HIV-negative adults, CSF raltegravir concentrations do not differ by ABCB1 3435C→T genotype but strongly correlate with plasma exposure.

Trial Registration

ClinicalTrials.gov NCT00729924 http://clinicaltrials.gov/show/NCT00729924

Neuropsychometric correlates of efavirenz pharmacokinetics and pharmacogenetics following a single oral dose

AIMS

To determine pharmacokinetic and pharmacogenomic correlates of efavirenz central nervous system (CNS) side effects following a single dose.

METHODS

Thirty-four healthy HIV-negative African Americans were administered a 600 mg dose of efavirenz. Blood samples for pharmacokinetics were drawn serially from 0 to 12 h post-dose. Neuropsychometric testing with drowsiness visual analogue scale, grooved pegboard and letter digit substitution tests was done the day prior to dosing and at 1, 2, 3, 4 and 6 h post-dose. Subjective CNS symptoms were assessed at 6 h post-dose. Composite CYP2B6 516/983 genotype was determined.

RESULTS

Pharmacokinetic indices reflecting increased plasma efavirenz exposure were associated with slower non-dominant hand grooved pegboard task completion (Cmax , P1 h  = 0.01, P2 h  = 0.05, P3 h  = 0.03, P4 h  = 0.01; AUC, P1 h  = 0.04; clearance P1 h  = 0.05, P2 h  = 0.02, P6 h  = 0.01). In a repeated measures model analysis that adjusted timing of neuropsychometric testing for timing of peak drug concentration, clearance (P < 0.001), AUC(0.312 h) (P = 0.001) and Cmax (P = 0.008) were associated with non-dominant grooved pegboard test performance. CYP2B6 genotype trended to correlate with non-dominant hand grooved pegboard at 4 and 6 h (P = 0.07 and 0.06). Decreased drowsiness at 6 h was associated with higher Cmax (P = 0.02).

CONCLUSIONS

Following a single dose of efavirenz, an association between pharmacokinetics and neuropsychometric performance was discernable. A weaker association between genotype and neurocognitive test performance is likely mediated by effect of genotype on plasma clearance. Strategies that lower Cmax during initial dosing may decrease CNS side effects.

Baseline tumour measurements predict survival in advanced non-small cell lung cancer

BACKGROUND

The association between tumour measurements and survival has been studied extensively in early-stage and locally advanced non-small cell lung cancer (NSCLC). We analysed these factors in patients with advanced NSCLC.

METHODS

Data were derived from the E4599 trial of paclitaxel-carboplatin±bevacizumab. Associations between the Response Evaluation Criteria in Solid Tumors (RECIST) baseline sum longest diameter (BSLD), response rate, progression-free survival (PFS) and overall survival (OS) were evaluated using univariate and multivariable Cox regression models.

RESULTS

A total of 759 of the 850 patients (89%) in the E4599 trial had measurable diseases and were included in this analysis. The median BSLD was 7.5 cm. BSLD predicted OS (hazard ratio (HR) 1.41; P<0.001) and had a trend towards association with PFS (HR 1.14; P=0.08). The median OS was 12.6 months for patients with BSLD <7.5 cm compared with 9.5 months for BSLD ≥ 7.5 cm. This association persisted in a multivariable model controlling multiple prognostic factors, including the presence and sites of extrathoracic disease (HR 1.24; P=0.01). There was no association between BSLD and response rate.

CONCLUSION

Tumour measurements are associated with survival in the E4599 trial. If validated in other populations, this parameter may provide important prognostic information to patients and clinicians.

Multisite EPR oximetry from multiple quadrature harmonics

Multisite continuous wave (CW) electron paramagnetic resonance (EPR) oximetry using multiple quadrature field modulation harmonics is presented. First, a recently developed digital receiver is used to extract multiple harmonics of field modulated projection data. Second, a forward model is presented that relates the projection data to unknown parameters, including linewidth at each site. Third, a maximum likelihood estimator of unknown parameters is reported using an iterative algorithm capable of jointly processing multiple quadrature harmonics. The data modeling and processing are applicable for parametric lineshapes under nonsaturating conditions. Joint processing of multiple harmonics leads to 2-3-fold acceleration of EPR data acquisition. For demonstration in two spatial dimensions, both simulations and phantom studies on an L-band system are reported.

Transretinal degeneration in ageing human retina: a multiphoton microscopy analysis

AIM

Retinal cell remodelling has been reported as a consistent feature of ageing. However, the degree to which this results in transretinal degeneration is unclear. To address this, the authors used multiphoton microscopy to quantify retinal degeneration in post-mortem human eyes of two age groups.

METHODS

Retinas from six young subjects (18-33 years old) and six older subjects (74-90 years old) were prepared as wholemount preparations. All retinas were stained with 4,6-diamidino-2-phenylindole and imaged by multiphoton confocal microscopy to quantify neuron densities in the retinal ganglion cell layer (RGCL), inner nuclear layer (INL) and outer nuclear layer (ONL). Neurons were counted using automated cell identification algorithms. All retinas were imaged hydrated to minimise tissue artefacts.

RESULTS

In both groups, 56% of the area within the central 4 mm eccentricity and 27% of the area with eccentricity between 4 mm and 7 mm were imaged. Compared with young subjects, the peak RGCL neuron loss in the aged subjects (25.5%) was at 1 mm eccentricity. INL and ONL neuron densities significantly decreased at 1-2 mm eccentricity (8.7%) and 0.5-4 mm eccentricity (15.6%) respectively (P <0.05). The reduction in neuron density in the INL corresponded, spatially, to the region with the greatest neuron loss in the RGCL and ONL.

CONCLUSIONS

This is the first study to correlate neurodegeneration in different populations of cells in the ageing retinas. These data confirm that the greatest neuronal loss occurs in the RGCL and ONL in human ageing retinas, whereas the INL is relatively preserved.

Evidence for viable, non-clonal but fatherless Boa constrictors

Parthenogenesis in vertebrates is considered an evolutionary novelty. In snakes, all of which exhibit genetic sex determination with ZZ : ZW sex chromosomes, this rare form of asexual reproduction has failed to yield viable female WW offspring. Only through complex experimental manipulations have WW females been produced, and only in fish and amphibians. Through microsatellite DNA fingerprinting, we provide the first evidence of facultative parthenogenesis in a Boa constrictor, identifying multiple, viable, non-experimentally induced females for the first time in any vertebrate lineage. Although the elevated homozygosity of the offspring in relation to the mother suggests that the mechanism responsible may be terminal fusion automixis, no males were produced, potentially indicating maternal sex chromosome hemizygosity (WO). These findings provide the first evidence of parthenogenesis in the family Boidae (Boas), and suggest that WW females may be more common within basal reptilian lineages than previously assumed.

Oncogenic mutations regulate tumor microenvironment through induction of growth factors and angiogenic mediators

Activating mutations in the tyrosine kinase domain of HER2 (ErbB2) have been identified in human cancers. Compared to wild-type HER2, mutant HER2 shows constitutively activate kinase activity and increased oncogenicity. Cells transformed by mutant HER2 are resistant to EGFR tyrosine kinase inhibitors and exhibit an attenuated response to the HER2 antibody trastuzumab. We investigated herein pathways through which mutant HER2 alters the extracellular environment, potentially leading to drug resistance and the effect of simultaneously targeting HER2 and the tumor cell microenvironment with a therapeutic intent. Expression of mutant HER2 in mammary epithelial cells activated autocrine transforming growth factor (TGF) β1 signaling through a mechanism involving Rac1 and JNK-AP1-dependent transcription. Cells transformed by an activating mutant of H-Ras (G12V) also expressed higher TGF-β1 level through Rac1 activation. In addition, mutant HER2 induced the EGFR ligands TGF-α and amphiregulin at the mRNA and protein levels. Vascular endothelial growth factor (VEGF), a target of the TGF-β-Smad transcriptional regulation, was also induced as a result of expression of mutant HER2. Inhibition of TGF-β signaling with the Alk5 small molecule inhibitor LY2109761 reduced growth and invasiveness of cells expressing mutant HER2. Combined inhibition of intracellular and paracrine effects of mutant HER2 by trastuzumab and the EGFR antibody cetuximab was more efficient than single-agent therapies. These data suggest that mutations in oncogenes such as HER2 and Ras not only alter intracellular signaling and also influence on other components of the tumor microenvironment by inducing several pro-invasive growth factors. In turn, these serve as extracellular targets of novel therapeutic strategies directed at both cancer-driving oncogenes and the modified tumor microenvironment.

Adjuvant chemotherapy, with or without postoperative radiotherapy, in operable non-small-cell lung cancer: two meta-analyses of individual patient data

BACKGROUND

Many randomised controlled trials have investigated the effect of adjuvant chemotherapy in operable non-small-cell lung cancer. We undertook two comprehensive systematic reviews and meta-analyses to establish the effects of adding adjuvant chemotherapy to surgery, or to surgery plus radiotherapy.

METHODS

We included randomised trials, not confounded by additional therapeutic differences between the two groups and that started randomisation on or after Jan 1, 1965, which compared surgery plus adjuvant chemotherapy versus surgery alone, or surgery plus adjuvant radiotherapy and chemotherapy versus surgery plus adjuvant radiotherapy. Updated individual patient data were collected, checked, and included in meta-analyses stratified by trial. The primary endpoint was overall survival, defined as time from randomisation until death by any cause. All analyses were by intention to treat.

FINDINGS

The first meta-analysis of surgery plus chemotherapy versus surgery alone was based on 34 trial comparisons and 8447 patients (3323 deaths). We recorded a benefit of adding chemotherapy after surgery (hazard ratio [HR] 0.86, 95% CI 0.81-0.92, p<0.0001), with an absolute increase in survival of 4% (95% CI 3-6) at 5 years (from 60% to 64%). The second meta-analysis of surgery plus radiotherapy and chemotherapy versus surgery plus radiotherapy was based on 13 trial comparisons and 2660 patients (1909 deaths). We recorded a benefit of adding chemotherapy to surgery plus radiotherapy (HR 0.88, 95% CI 0.81-0.97, p=0.009), representing an absolute improvement in survival of 4% (95% CI 1-8) at 5 years (from 29% to 33%). In both meta-analyses we noted little variation in effect according to the type of chemotherapy, other trial characteristics, or patient subgroup.

INTERPRETATION

The addition of adjuvant chemotherapy after surgery for patients with operable non-small-cell lung cancer improves survival, irrespective of whether chemotherapy was adjuvant to surgery alone or adjuvant to surgery plus radiotherapy.

FUNDING

UK Medical Research Council, Institut Gustave-Roussy, Programme Hospitalier de Recherche Clinique (AOM 05 209), Ligue Nationale Contre le Cancer, and Sanofi-Aventis.

Topography of neuron loss in the retinal ganglion cell layer in human glaucoma

AIM

To determine if retinal ganglion cell (RGC) loss influences the loss of surrounding RGCs to generate clustered patterns of cell death in human glaucoma. It is hypothesised that retinal ganglion cell loss accelerates the loss of surrounding cells to generate, at a local, cellular scale, clustered patterns of retinal of RGC death. The absence of these interactions would result in a diffuse pattern RGC loss.

METHOD

Six glaucomatous retinas (67-83 years old) and six age-matched control retinas (61-89 years old) were prepared as wholemounts and stained by 4',6-diamidino-2-phenylindole (DAPI) solution (3 microg/ml in PBS). An area corresponding to central 14 degrees of the visual field was imaged. The nearest-neighbour distribution was determined for cells in both normal and glaucomatous RGCL.

RESULTS

Clustered RGC loss in human glaucoma was observed on a background of diffuse loss. The mean nearest-neighbour distance (NND) of the glaucomatous retinas was significantly higher than with controls (p<0.001). The distribution of NND in glaucomatous retinas was skewed to the higher values with a higher positive kurtosis relative to controls. The quantitative analysis of the pattern of cell loss is supported by the visual inspection of the patterns of cell loss.

DISCUSSION

The nearest-neighbour analysis is consistent with the presence of two patterns of cell loss in the RGCL in glaucoma. While the diffuse of cell loss can account for an overall reduction in the RGC population, an additional non-random pattern is consistent with the hypothesis that RGC loss has a local influence on the viability of surrounding cells.

Predicting gene promoter methylation in non-small-cell lung cancer by evaluating sputum and serum

The use of 5-methylcytosine demethylating agents in conjunction with inhibitors of histone deacetylation may offer a new therapeutic strategy for lung cancer. Monitoring the efficacy of gene demethylating treatment directly within the tumour may be difficult due to tumour location. This study determined the positive and negative predictive values of sputum and serum for detecting gene methylation in primary lung cancer. A panel of eight genes was evaluated by comparing methylation detected in the primary tumour biopsy to serum and sputum obtained from 72 patients with Stage III lung cancer. The prevalence for methylation of the eight genes in sputum (21–43%) approximated to that seen in tumours, but was 0.7–4.3-fold greater than detected in serum. Sputum was superior to serum in classifying the methylation status of genes in the tumour biopsy. The positive predictive value of the top four genes (p16, DAPK, PAX5 β, and GATA5) was 44–72% with a negative predictive value for these genes ⩾70%. The highest specificity was seen for the p16 gene, and this was associated with a odds ratio of six for methylation in the tumour when this gene was methylated in sputum. In contrast, for serum, the individual sensitivity for all genes was 6–27%. Evaluating the combined effect of methylation of at least one of the four most significant genes in sputum increased the positive predictive value to 86%. These studies demonstrate that sputum can be used effectively as a surrogate for tumour tissue to predict the methylation status of advanced lung cancer where biopsy is not feasible.

Gene therapy for breast and ovarian cancer with BRCA1

As an initial step toward gene therapy for ovarian cancer, we conducted a Phase 1 trial to assess the pharmacokinetics and toxicity of intraperitoneal BRCA1sv retroviral vector therapy. Gene transfer and expression were documented by PCR, southern blot, RT-PCR and nuclease protection assays. Pharmacokinetics were assessed by PCR and southern blots detecting vector DNA, and toxicity was evaluated by clinical exam and fluid analysis. Three of twelve patients developed an acute sterile peritonitis which spontaneously resolved within 48 hours. Plasma and peritoneal antibodies to the retroviral envelope protein were detected only in patients treated with the highest dose levels but not in others, despite repeat dosing for an interval of up to four months. Eight patients showed stable disease for 4 to 16 weeks. Three patients showed tumor reduction with diminished miliary tumor implants at reoperation (two patients) and radiographic shrinkage of measurable disease (one patient). Ovarian cancer may provide an imporant model for retroviral gene therapy studies due to vector stability, minimal antibody response, and access to tumor by intraperitoneal therapy.

Phase II study of the farnesyl transferase inhibitor R115777 in patients with sensitive relapse small-cell lung cancer

BACKGROUND

R115777 (tipifarnib, Zarnestra) is a farnesyl transferase inhibitor that blocks the farnesylation of proteins involved in signal transduction pathways critical for cell proliferation and survival. This multicenter phase II study was conducted to determine the efficacy, tolerability and pharmacokinetics of R115777 in patients with relapsed small-cell lung cancer (SCLC).

PATIENTS AND METHODS

Patients who had a partial or complete response to their initial chemotherapy regimen, followed by at least 3 months off treatment before relapse (sensitive relapse) were eligible. R115777 was administered in 3-week cycles at a dose of 400 mg orally twice daily for 14 consecutive days followed by 7 days off treatment.

RESULTS

Twenty-two patients were enrolled. The median progression-free survival was 1.4 months and median overall survival was 6.8 months. Non-hematological toxicities were predominantly grade 1-2 and included nausea (64%) and fatigue (60%). Grade 3-4 granulocytopenia and thrombocytopenia occurred in 27% and 23% of patients, respectively. Febrile neutropenia was not observed. Pharmacokinetic studies demonstrated peak plasma concentrations of R115777 2.6-4.5 h after oral dosing and no significant drug accumulation. The trial was terminated because no objective responses were observed in 20 patients evaluable for response.

CONCLUSIONS

R115777 showed no significant antitumor activity as a single agent in sensitive-relapse SCLC.

Mutations which enhance the replication of dengue virus type 4 and an antigenic chimeric dengue virus type 2/4 vaccine candidate in Vero cells

Mutations which increase the replication of dengue viruses in cell culture would greatly facilitate the manufacture of both a live attenuated or inactivated dengue virus vaccine. We have identified eight missense mutations in dengue virus type 4 (DEN4) that increase the plaque size and kinetics of replication of recombinant DEN4 virus in Vero cells. DEN4 viruses bearing these Vero cell adaptation mutations were also evaluated for the level of replication in the brains of mice. Two of these eight recombinant viruses expressing distinct mutations in NS3 were both restricted in replication in the brains of suckling mice. In contrast, six recombinant viruses, each encoding individual mutations in NS4B (five) or in NS5 (one), were not attenuated in mouse brain. Recombinant viruses encoding various combinations of these Vero cell adaptation mutations did not demonstrate enhanced replication in Vero cells over that exhibited by the single mutations. Finally, addition of a subset of the above non-attenuating, adaptation mutations to a DEN2/4 chimeric vaccine candidate was found to increase the virus yield in Vero cells by up to 500-fold. The importance of these Vero cell adaptation mutations in flavivirus vaccine design and development is discussed.

Chondroblastoma of the temporal bone involving the temporomandibular joint, mandibular condyle, and middle cranial fossa: case report and review of the literature

Chondroblastoma is a highly destructive tumor, derived from immature cartilage cells, typically occurring in epiphyses of the long bones of adolescents and young adults. Those occurring in the temporal bone and TMJ area are likely to mimic TMJ symptoms. This report describes a unique case in which a chondroblastoma resulted in extensive destruction of the temporal bone, temporomandibular joint, mandibular condyle, and cranial base, including gross intracranial and extracranial involvement. With appropriate surgical management, the outcome for patients with chondroblastoma of the temporomandibular region is quite favorable. This case brings the total reported chondroblastomas to 59 in the temporal bone and eight in the mandibular condyle as of the date of submission of this article for publication.

Docetaxel Combined With Trastuzumab Is an Active Regimen in HER-2 3+ Overexpressing and Fluorescent In Situ Hybridization–Positive Metastatic Breast Cancer: A Multi-Institutional Phase II Trial

Purpose

To determine the efficacy and safety of weekly docetaxel and trastuzumab as first- or second-line therapy in women with HER-2–overexpressing metastatic breast cancer and to correlate the efficacy of trastuzumab with HER-2 status as determined by immunohistochemistry assay and fluorescent in situ hybridization (FISH).

Patients and Methods

Twenty-six women with HER-2–positive (HercepTest [Dako Corp, Carpenteria, CA]2 to 3+) metastatic breast cancer were enrolled onto this study of trastuzumab (4 mg/kg load; 2 mg/kg/wk administered intravenously) and docetaxel (35 mg/m2/wk for 6 weeks).

Results

Using an intent-to-treat analysis, the overall response rate was 50% (13 of 26 patients). Eight patients (31%) had a period of stable disease posttherapy. Among HER-2 3+ patients, the overall response rate was 63% (12 of 19 patients) compared with a 14% response rate (one of seven patients) for HER-2 2+ patients (P = .07). Patients with FISH-positive tumors experienced an overall response rate of 64%. Median time to progression was 12.4 months for the entire cohort (HER-2 3+ tumors, 12.3 months; HER-2 2+ lesions, 9.5 months) and median survival was 22.1 months. All HER-2 3+ patients were FISH-positive; the only HER-2 2+ patient responding to treatment was also FISH-positive. Grade 4 toxicities occurred in four patients; most toxicities were mild.

Conclusion

Trastuzumab plus docetaxel is an active and well-tolerated regimen in women with HER-2 3+ overexpressing or FISH-positive metastatic breast cancer.

Docetaxel and cisplatin in patients with advanced non small-cell lung cancer (NSCLC): a multicenter phase II trial

We examined the safety and efficacy of the docetaxel/cisplatin combination in patients with advanced, previously untreated NSCLC and evaluated changes in quality of life over time. Docetaxel was administered before cisplatin (both 75 mg/m2, 1-hour infusions) every 3 weeks to 47 patients with stage IIIB or stage IV NSCLC. Patients also received premedication of oral dexamethasone. The median age (range) of patients was 62 (45-78) years and 26 patients (55.3%) had adenocarcinoma. Of the 40 patients evaluable for response, one achieved a complete response and 14 had partial responses; the response rate was 37.5% (95% confidence intervals; 22.5, 52.5). In the intent-to-treat population the overall response rate was 31.9%. Time to response ranged from 3 to 20 weeks, and the median duration of response was 34.6 weeks. Median survival and median time to progression were 11.3 months and 18.9 weeks, respectively. One-year survival was 40%. Grade 3 or 4 neutropenia and febrile neutropenia were observed in 74.4% and 12.8% of patients, respectively. Severe asthenia was seen in 14.9% of patients. Other grade 3 or 4 toxicities included nausea (eight patients), vomiting (five), neurosensory effects (six), neuromotor effects (five), diarrhea (four), and infection (three). There was an improvement in emotional well-being; however, the overall quality of life score did not change with treatment. Docetaxel administered in combination with cisplatin is an active regimen in patients with NSCLC. This regimen of docetaxel (75 mg/m2) and cisplatin (75 mg/m2) repeated at 3-week intervals is being evaluated in an ongoing Eastern Cooperative Oncology Group (ECOG) randomized study in patients with advanced and metastatic NSCLC.

Visual responses of crayfish ocular motoneurons: an information theoretical analysis

Motoneuron responses were elicited by global visual motion and stepwise displacements of an illuminated stripe. Stimulus protocols were identical to those used in previous behavioral studies of compensatory eyestalk reflexes. The firing rates and directional selectivity of the motoneuron responses were measured with respect to four stimulus dimensions (spatial frequency, contrast, angular displacement and velocity). The directional selectivity of the motoneuron response was correlated to the previously measured gain of the reflex for each stimulus dimension. The information theoretical analysis is based upon Kullback-Leibler (K-L) distances which measure the dissimilarity of responses to different stimuli. K-L distances for single neurons are strongly influenced by the mean rate difference of the responses to any pair of stimuli. Because of redundancy, the joint K-L distances of pairs of neurons were less than the sum of the K-L distances of the individual neurons. Furthermore, the joint K-L distances were only weakly influenced by correlations among coactivated neurons. For most of the stimulus dimensions, the K-L distances of single motoneurons were not sufficient to account for the stimulus discriminations exhibited by the eyestalk reflex which typically required the summed output of 2 to 5 motoneurons. Thus the behaviorally relevant information is encoded in the motoneuron ensemble. The minimum time required to discriminate the direction of motion (the encoding window) for a single motoneuron is about 380 to 480 ms (including a 175 ms response latency) for stepwise displacements and up to 1.0 s for global motion. During this period a motoneuron fires 2 to 3 impulses.

Mortality during hospitalisation for pneumonia in Alberta, Canada, is associated with physician volume

The association of mortality with patient factors (severity of illness, comorbidity), physician factors (specialty training, prehospitalisation visit, in-hospital consultation, volume of patients seen per physician) and healthcare organisation factors (patient-travel distances, regional beds per capita, admitting hospital-bed occupancy, admitting hospital-bed turnover, hospital location, volume of pneumonia cases per hospital) after hospital admission with community-acquired pneumonia was investigated using administrative data from Alberta, Canada from April 1, 1994-March 31, 1999. During the 5-yr study period there were 43,642 pneumonia hospitalisations, with an 11% in-hospital and 26% 1-yr mortality. Patient severity of illness and comorbidity were the strongest predictors of increased mortality. Physicians with the highest in-hospital pneumonia patient volume (>27 patients x yr(-1)) cared for patients with greater severity/comorbidity, but with decreased odds of in-hospital mortality, compared with the lowest volume physicians (less than seven patients per year). The effects of internal medicine specialist or subspecialist care were mixed, with a reduction in deaths for the first 72 h and an increase in in-hospital deaths. Prehospitalisation visit by a physician was associated with decreased mortality. Healthcare organisation factors were the least strong predictor of mortality, demonstrating an effect only for 1-yr mortality in those discharged alive from hospital. Admissions to larger volume or metropolitan hospitals were associated with a decrease in mortality. Severity of illness and comorbidity had the strongest association with mortality. The first association of high-volume physician and pre-hospital care with decreased in-hospital mortality for community-acquired pneumonia is reported.