31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

Clinical and Genetic Features in Patients With Reflex Bathing Epilepsy

Objectiv

Clinical and Genetic Features in Patients With Reflex Bathing Epilepsy

To describe the clinical and genetic findings in a cohort of subjects with bathing epilepsy, a rare form of reflex epilepsy

Real‐world data on cannabidiol treatment of various epilepsy subtypes: A retrospective, multicenter study

Abstract Objective Cannabidiol (CBD) is approved for treatment of Dravet syndrome (DS), Lennox‐Gastaut syndrome (LGS), and tuberous sclerosis complex (TSC). Several studies suggest antiseizure effects also beyond these three epilepsy syndromes. Methods In a retrospective multicenter study, we analyzed the efficacy and tolerability of CBD in patients with epilepsy at 16 epilepsy centers. Results The study cohort comprised 311 patients with epilepsy with a median age of 11.3 (0‐72) years (235 children and adolescents, 76 adults). Therapy with CBD was off‐label in 91.3% of cases due to age, epilepsy subtype, lack of adjunct therapy with clobazam, and/or higher dose applied. CBD titration regimens were slower than recommended, with good tolerability of higher doses particularly in children. Of all patients, 36.9% experienced a reduction in seizure frequency of >50%, independent of their epilepsy subtype or clobazam co‐medication. The median observation period was 15.8 months. About one third of all patients discontinued therapy within the observation period due to adverse effects or lack of efficacy. Adverse effects were reported frequently (46.9%). Significance Our study highlights that CBD has an antiseizure effect comparable to other antiseizure medications with a positive safety profile independent of the epilepsy subtype. Comedication with clobazam was not associated with a better outcome. Higher doses to achieve seizure frequency reduction were safe, particularly in children. These findings call for further trials for an extended approval of CBD for other epilepsy subtypes and for children <2 years of age

Figure 5

Figure 5. Family pedigrees from published cases. Fig.5a. COL4A2 c. 2399 G>A; p. G800E. Ref. Ha et al., 2016. Fig.5b. COL4A2 c. 3455 G>A; p. G1152D. Ref. Yoneda et al., 2012. Fig.5c. COL4A1 c. 1249G>C; p.G417R. Ref. Giorgio et al., 2015. Fig.5d. COL4A1 c.3796G>C; p.G1266R. Ref. Shah et al., 2012. Fig.5e: COL4A1 c.2662G>C; p.G888R. Ref. Giorgio et al., 2015. Fig.5f: COL4A1 p.G562E. Ref. Vahedi et al., 2003 and Vahedi et al., 2007. Fig.5g.: COL4A1 p. G749S. Ref. Gasparini et al., 2006. Fig.5h: COL4A1 c.3389G>A; p.G1130D. Ref. Breedved et al. 2006 Fig.5i: COL4A1 c.2159G>A. Ref. Tonduti et al., 2012. Fig.5j: COL4A1 c.3715G>A; p.G1239R. Ref. Takenouchi et al., 2015. Fig.5k: COL4A1 c. 2645G>A. Ref. Shah et al., 2012. Fig.5l: COL4A1 c.1973 G>A. Ref. Livingston et al., 2011. Fig.5m: COL4A1 c.4031G>C; p.G1344A. Ref. Leung et al., 2012. Fig.5n: COL4A2 c.3455G>A; p.G1152D. Ref. Yoneda et al., 2012. Fig.5o: COL4A1 c.2085del; p. G696fs. Ref. Lemmens et al., 2013. wt/m: wild-type/mutated

Additional material

Table 1 summarizes the methods of identification of COL4A1/2 mutations in the cohort of new patients. Table 2 reports the phenotypes of previously-published patients with COL4A1/2 mutations and epilepsy. Tables 3a/b describes the clinical, EEG and brain MRI data of the new cohort of patients with COL4A1/2 mutations. Additional Method describes immunohistochemistry performed from consented surplus resected tissue from 1 case

Data from: Neurologic phenotypes associated with COL4A1/2 mutations: expanding the spectrum of disease

Objective: To characterize the neurological phenotypes associated with COL4A1/2 mutations and to seek genotype-phenotype correlation. Methods We analyzed clinical, EEG and neuroimaging data of 44 new, and 55 previously reported patients with COL4A1/COL4A2 mutations. Results Childhood-onset focal seizures, frequently complicated by status epilepticus and resistance to anti-epileptic drugs, was the most common phenotype. EEG typically showed focal epileptiform discharges in the context of other abnormalities, including generalized sharp waves or slowing. In 46.4% of new patients with focal seizures, porencephalic cysts on brain MRI co-localized with the area of the focal epileptiform discharges. In patients with porencephalic cysts, brain MRI frequently also showed extensive white matter abnormalities, consistent with the finding of diffuse cerebral disturbance on EEG. Notably, we also identified a subgroup of patients with epilepsy as their main clinical feature, in which brain MRI showed non-specific findings, in particular periventricular leukoencephalopathy and ventricular asymmetry. Analysis of fifteen pedigrees suggested a worsening of the severity of clinical phenotype in succeeding generations, particularly when maternally inherited. Mutations associated with epilepsy were spread across COL4A1 and a clear genotype-phenotype correlation did not emerge. Conclusions COL4A1/COL4A2 mutations typically cause a severe neurological condition and a broader spectrum of milder phenotypes, in which epilepsy is the predominant feature. Early identification of patients carrying COL4A1/COL4A2 mutations may have important clinical consequences, whilst for research efforts, omission from large-scale epilepsy sequencing studies of individuals with abnormalities on brain MRI may generate misleading estimates of the genetic contribution to the epilepsies overall