Differences In Clinical Response Research Articles

#1491 Management of immune thrombotic thrombocytopenic purpura without therapeutic plasma exchange

Abstract Background and Aims Immune thrombotic thrombocytopenic purpura (iTTP) is a rare, life-threatening autoimmune disorder caused by ADAMTS13 deficiency. The anti-VWF nanobody Caplacizumab is approved for iTTP treatment, reducing the need for therapeutic plasma exchange (TPE) and improving platelet recovery and survival. This study evaluates the treatment of acute iTTP with caplacizumab and immunosuppression, but without TPE, in comparison to the conventional management with TPE, caplacizumab and immunosuppression. Method All patients in this study were identified from the Austrian Thrombotic Microangiopathy Registry (ATMAR) and the German REACT-2020 TTP registry (ClinicalTrials.gov identifier: NCT04985318). A total of 42 acute iTTP episodes in 41 patients were managed with a treatment regimen aimed at avoiding first-line TPE if the platelet count increased after the first dose of 10 mg caplacizumab, and the patient's condition and organ function remained stable (TPE-free cohort). This treatment modification was implemented based on shared decision making. An extensive efficacy and safety analysis of this approach was performed, in comparison with a control group of 59 iTTP patients, receiving frontline caplacizumab treatment with TPE and immunosuppression (TPE cohort). The main outcome was time to platelet count normalization. Secondary outcomes included clinical response, exacerbation, refractoriness, and iTTP-related deaths. Results The primary outcome parameter, time to platelet count normalization, was not significantly different between TPE-free and TPE-based management (Kaplan-Meier estimator and log-rank test, Table 1 and Fig. 1). The median time to platelet count normalization was 3 days in the TPE-free cohort and 4 days in the TPE cohort. There were no significant differences in clinical response, exacerbations, refractoriness, or iTTP-related deaths. For evaluation of the short-term treatment response, both cohorts were assessed for the time to platelet count doubling. The median time to platelet count doubling was 1 day in both cohorts. Four patients in the TPE-free cohort did not immediately respond to the first caplacizumab injection and subsequently underwent TPE, after a maximum monitoring period of 40 hours. In these patients, TPE was initiated at a median of 1.5 days after the first caplacizumab dose, and TPE was performed for a median of 4.5 days. This delayed platelet response could be attributed to concomitant diseases and factors, e.g. active HIV and hepatitis B virus coinfection, active CMV infection, concomitant antiplatelet antibodies in association with an ovarian teratoma, and multiple platelet transfusions before the correct diagnosis. During overall follow-up, complications were observed in 11 patients (26.2%) in the TPE-free group and 16 patients (27.1%) in the TPE group, excluding complications of iTTP that were evaluated as outcome parameters. Serious complications occurred in 4 patients (6.8%) from the TPE cohort while on TPE, including severe systemic anaphylactic reactions with severe hypotension, generalized seizure and supraventricular tachycardia. Bleeding complications were reported without a significant difference between groups. Conclusion For the first time since the introduction of TPE in the early 1990s, the results of our study systematically challenge the absolute need for TPE and suggest a paradigm shift in acute iTTP management. In detail, our treatment approach was successfully implemented in 38 of 42 acute iTTP episodes (90.5%). We observed no significant difference in the time to platelet count normalization between patients with iTTP treated with and without TPE. The analysis of key secondary outcomes did not reveal significant differences in the proportion of patients who achieved a clinical response or experienced exacerbations, refractoriness, or TTP-related deaths. In conclusion, Caplacizumab and immunosuppression, without TPE, rapidly controlled microvascular thrombosis and achieved a sustained clinical response in iTTP.

The impact of Vitreo-Macular interface abnormalities on the response to Anti-VEGF therapy for centre involving diabetic macular oedema.

The influence of Vitreomacular Interface Abnormalities (VMIA) such as Epiretinal Membrane (ERM) and/or vitreomacular traction (VMT) on the response of patients with Centre Involving Diabetic Macular Edema (CIDME) to standard of care Anti-VEGF medications is under-researched. The aims of this study were: 1) To determine the incidence of VMIA at baseline and 12 months amongst treatment naive patients commencing anti-VEGF treatment 2) To compare the response to Anti-VEGF medications at 3 monthly intervals for 12 months in a large cohort of patients with and without VMIA on their baseline OCT scan. Response was determined in terms of: number of injections, central macular thickness and visual acuity. A retrospective case notes review of treatment naïve patients with newly diagnosed CIDME. Included patients had been commenced on intravitreal Anti-VEGF injections (ranibizumab or aflibercept) at a single centre. Inclusion criteria were: treatment naïve DME patients with a CMT of 400μ or more receiving anti-VEGF treatment with at least 12 months follow up and in whom macular OCT scans and visual acuity (VA) measurements were available within two weeks of baseline, 3, 6, 9 and 12 months. Exclusion criteria included: previous intravitreal therapy, previous vitrectomy, cataract surgery during the follow-up period, concurrent eye conditions affecting vision or CMT. 119 eyes met the inclusion criteria and underwent analysis. Groups were comparable in their baseline demographics. Baseline CMT measurements were comparable at baseline (417μ and 430μ in the No-VMIA and VMIA groups respectively) and improved to approximately 300μ in both groups. From 6 months CMT continued to improve in the no-VMIA while progressively deteriorating in the VMIA group. Change in CMT was statistically different at 12 months between the 2 groups (108μ and 79μ, p= 0.04). There was a mean of 7 injections after 12 months. Our study has shown a 46% incidence of VMIA amongst patients newly diagnosed with centre involving DME undergoing treatment with anti-VEGF injections. We have also demonstrated a significant difference in CMT and VA response to anti-VEGF treatment in patients with and without VMIA. Initial response was similar between the 2 groups up until 6 months. From 6 to 12 months significant differences in treatment response emerged. Differences in clinical response between patients with and without VMIA may help guide further prospective controlled studies and optimise treatment strategies.

The analysis of transcriptomic signature of TNBC—searching for the potential RNA-based predictive biomarkers to determine the chemotherapy sensitivity

AbstractNeoadjuvant chemotherapy is the foundation treatment for triple-negative breast cancer (TNBC) and frequently results in pathological complete response (pCR). However, there are large differences in clinical response and survival after neoadjuvant chemotherapy of TNBC patients. The aim was to identify genes whose expression significantly associates with the efficacy of neoadjuvant chemotherapy in patients with TNBC. Transcriptomes of 46 formalin-fixed paraffin-embedded (FFPE) tumor samples from TNBC patients were analyzed by RNA-seq by comparing 26 TNBCs with pCR versus 20 TNBCs with pathological partial remission (pPR). Subsequently, we narrowed down the list of genes to those that strongly correlated with drug sensitivity of 63 breast cancer cell lines based on Dependency Map Consortium data re-analysis. Furthermore, the list of genes was limited to those presenting specific expression in breast tumor cells as revealed in three large published single-cell RNA-seq breast cancer datasets. Finally, we analyzed which of the selected genes were significantly associated with overall survival (OS) in TNBC TCGA dataset. A total of 105 genes were significantly differentially expressed in comparison between pPR versus pCR. As revealed by PLSR analysis in breast cancer cell lines, out of 105 deregulated genes, 42 were associated with sensitivity to docetaxel, doxorubicin, paclitaxel, and/or cyclophosphamide. We found that 24 out of 42 sensitivity-associated genes displayed intermediate or strong expression in breast malignant cells using single-cell RNAseq re-analysis. Finally, 10 out of 24 genes were significantly associated with overall survival in TNBC TCGA dataset. Our RNA-seq-based findings suggest that there might be transcriptomic signature consisted of 24 genes specifically expressed in tumor malignant cells for predicting neoadjuvant response in FFPE samples from TNBC patients prior to treatment initiation. Additionally, nine out of 24 genes were potential survival predictors in TNBC. This group of 24 genes should be further investigated for its potential to be translated into a predictive test(s).

Abstract PO3-01-12: Clinicopathologic Factors affecting response in patients with Estrogen receptor-positive and Human Epidermal Growth Factor Receptor-negative breast cancer receiving neoadjuvant chemotherapy

Abstract Background: The evolution of Neoadjuvant chemotherapy(NAC) regimen has enabled the down-staging of locally advanced breast cancer, allowing patients to undergo breast conserving surgery. NAC is known to be effective in triple-negative breast cancer (TNBC) and HER2-positive breast cancer. However, the role of NAC in hormone receptor-positive and HER2-negative (HR+HER2-) breast cancer patients remains unclear. In this study, we aimed to explore the utility of NAC for estrogen receptor-positive and HER2-negative (ER+HER2-) breast cancer patients. Methods: Clinical data were collected from 120 patients who were diagnosed with estrogen receptor (ER)-positive and HER2-negative breast cancer and received neoadjuvant chemotherapy between July, 2017 and April, 2023 at Seoul St Mary’s Hospital (Seoul, Korea). We analyzed the factors that affect clinical response subgroups, including pathologic complete response (pCR), partial response (PR), stable disease(SD), and progressive disease (PD), following neoadjuvant chemotherapy. The median follow-up period was 17 months. < Results: Among 120 patients after NAC, 5.8% achieved pCR, while 67.5% had a partial response. The median age at the time of surgery was 55 years at pCR group, 49 years at PR group, 47 years at SD group, and 49 years at PD group. Although the age of patients achieving pathological complete response was higher, this differences was not statistically significant. Patients achieving pCR had a higher incidence of progesterone receptor (PR) negativity (pCR 71.4% vs PR 30.9%, p=0.011) and higher levels of Ki-67 expression than those who did not achieve pCR (71.7% vs 35.6%, p=0.003). Also, there was no significant difference in Androgen receptor (AR) and HER-2 expression between the groups. Tumor size was also significantly associated with clinical response (p=0.003). However, no differences in clinical response was observed between patients with lymph node metastasis (p=0.221). Our analysis of 107 patients who were clinically N positive before NAC showed that the Ki-67 index level was the only factor found to affect nodal pCR. In addition, in the non-pCR group, patients with a Ki-67 index of less than 20% after neoadjuvant had a significantly better disease-free survival (5yr DFS, 79.8% vs 65.9%, p=0.039) Conclusion: Our analysis revealed that patients with higher levels of Ki-67 and lower level of PR expression were more likely to achieve pCR or PR. Also, decrease in Ki-67 index was confirmed to be an important prognostic factor of ER+ HER2- breast cancer. A combination of clinical and molecular factors, such as tumor size, progesterone receptor expression, and Ki-67 expression, can be used to optimize treatment plans and improve outcomes for the patient population. Citation Format: Jin Ah Lee, Young Joo Lee, Dooreh Kim, Chang Ik Yoon, Woo-Chan Park, Soo Youn Bae. Clinicopathologic Factors affecting response in patients with Estrogen receptor-positive and Human Epidermal Growth Factor Receptor-negative breast cancer receiving neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-01-12.

Consistent efficacy outcomes between phase 2 and phase 3 trialsin Crohn's disease or ulcerative colitis in adults: a meta-analysis.

The approval of novel biologic agents and small molecules for the treatment of Crohn's disease (CD) and ulcerative colitis (UC) is dependent on phase 3 randomized controlled trials (RCTs). However, these trials sometimes fail to achieve the expected efficacy outcomes observed in phase 2 trials. We conducted a systematic review of RCTs that evaluated biologic agents and small molecules using paired regimens in both phase 2 and phase 3. We searched Medline, EMBASE, and Cochrane databases up until February 13, 2024. The revised Cochrane tool was utilized to assess the risk of bias. A generalized linear mixed-effects model (GLMM) was employed to estimate the odds ratios (ORs) for efficacy outcomes in phase 2 trials compared to phase 3. We identified a total of 23 trials with 10 paired regimens for CD and 30 trials with 11 paired regimens for UC. The GLMM analysis revealed that phase 2 CD trials had higher outcomes measured by the Crohn's Disease Activity Index (CDAI) by 9-13% without statistical significance: CDAI-150: OR, 1.12 (95% CI 0.83-1.51, p = 0.41); CDAI-100: OR, 1.09 (95% CI 0.88-1.35, p = 0.40); or CDAI-70: OR, 1.13 (95% CI 0.61-2.08, p = 0.66). For UC, two efficacy outcomes were estimated to be equally reported in phase 2/phase 3 pairs: clinical remission: OR, 1.00 (95% CI 0.83-1.20, p = 0.96); endoscopic improvement: OR, 0.98 (95% CI 0.83-1.15, p = 0.79). However, the rate of clinical response was underestimated in phase 2 by 19%: OR, 0.81 (95% CI 0.70-0.95, p = 0.03). The inclusion criterion for the type of Mayo score for UC had a significant interaction with the study phase to influence the difference in clinical response (p = 0.002). Our findings suggest that the main efficacy outcomes for CD and UC remain consistent between phase 2 and phase 3 trials, except for UC response rates. The efficacy data obtained from phase 2 trials can be considered reliable for the design of subsequent phase 3 trials. PROSPERO (CRD42023407947).

High-Loading-Dose Colistin with Nebulized Administration for Carbapenem-Resistant Acinetobacter baumannii Pneumonia in Critically Ill Patients: A Retrospective Cohort Study.

Carbapenem-resistant Acinetobacter baumannii (CRAB) infections pose a serious threat, with high morbidity and mortality rates. This retrospective cohort study, conducted at Nakornping Hospital between January 2015 and October 2022, aimed to evaluate the efficacy and safety of a high loading dose (LD) of colistin combined with nebulized colistin in critically ill patients with CRAB pneumonia. Of the 261 patients included, 95 received LD colistin, and 166 received LD colistin with nebulized colistin. Multivariate Cox regression analysis, adjusted for baseline covariates using inverse probability weighting, showed no significant difference in 30-day survival between patients who received LD colistin and those who received LD colistin with nebulized colistin (adjusted hazard ratio [aHR]: 1.17, 95% confidence interval [CI]: 0.80-1.72, p = 0.418). Likewise, there were no significant differences in clinical response (aHR: 0.93, 95% CI: 0.66-1.31, p = 0.688), microbiological response (aHR: 1.21, 95% CI: 0.85-1.73, p = 0.279), or nephrotoxicity (aHR: 1.14, 95% CI: 0.79-1.64, p = 0.492) between the two treatment groups. No significant adverse events related to nebulized colistin were reported. These findings suggest that the addition of nebulized colistin may not offer additional benefits in terms of 30-day survival, clinical or microbiological response, or nephrotoxicity in these patients.

Real-world effectiveness of ustekinumab and vedolizumab in TNF-exposed pediatric patients with ulcerative colitis.

Vedolizumab (VDZ) and ustekinumab (UST) are second-line treatments in pediatric patients with ulcerative colitis (UC) refractory to antitumor necrosis factor (anti-TNF) therapy. Pediatric studies comparing the effectiveness of these medications are lacking. Using a registry from ImproveCareNow (ICN), a global research network in pediatric inflammatory bowel disease, we compared the effectiveness of UST and VDZ in anti-TNF refractory UC. We performed a propensity-score weighted regression analysis to compare corticosteroid-free clinical remission (CFCR) at 6 months from starting second-line therapy. Sensitivity analyses tested the robustness of our findings to different ways of handling missing outcome data. Secondary analyses evaluated alternative proxies of response and infection risk. Our cohort included 262 patients on VDZ and 74 patients on UST. At baseline, the two groups differed on their mean pediatric UC activity index (PUCAI) (p = 0.03) but were otherwise similar. At Month 6, 28.3% of patients on VDZ and 25.8% of those on UST achieved CFCR (p = 0.76). Our primary model showed no difference in CFCR (odds ratio: 0.81; 95% confidence interval [CI]: 0.41-1.59) (p = 0.54). The time to biologic discontinuation was similar in both groups (hazard ratio: 1.26; 95% CI: 0.76-2.08) (p = 0.36), with the reference group being VDZ, and we found no differences in clinical response, growth parameters, hospitalizations, surgeries, infections, or malignancy risk. Sensitivity analyses supported these findings of similar effectiveness. UST and VDZ are similarly effective for inducing clinical remission in anti-TNF refractory UC in pediatric patients. Providers should consider safety, tolerability, cost, and comorbidities when deciding between these therapies.

Sex differences in clinical response to deep brain stimulation in resistant obsessive-compulsive disorder

IntroductionDeep brain stimulation (DBS) is an effective alternative to treat severe refractory obsessive-compulsive disorder (OCD), although little is known on factors predicting response. The objective of this study was to explore potential sex differences in the pattern of response to DBS in OCD patients. MethodsWe conducted a prospective observational study in 25 patients with severe resistant OCD. Response to treatment was defined as a ≥35% reduction in Yale-Brown Obsessive Compulsive Scale (Y-BOCS) score. Logistic regression models were calculated to measure the likelihood of response at short and long-term follow-up by sex as measured by Y-BOCS score. Similar analyses were carried out to study changes in depressive symptomatology assessed with the Hamilton Depression Rating Scale (HDRS). Additionally, effect sizes were calculated to assess clinical significance. ResultsWe did not observe significant clinical differences between men and women prior to DBS implantation, nor in the response after one year of stimulation. At long-term follow-up, 76.9% of men could be considered responders to DBS versus only 33.3% of women. The final response odds ratio in men was 10.05 with significant confidence intervals (88.90–1.14). No other predictors of response were identified. The sex difference in Y-BOCS reduction was clinically significant, with an effect size of 3.2. The main limitation was the small sample size. ConclusionsOur results suggest that gender could influence the long-term response to DBS in OCD, a finding that needs to be confirmed in new studies given the paucity of results on predictors of response to DBS.

A RANDOMIZED, PLACEBO-CONTROLLED TRIAL OF PSYLLIUM FIBER AND FECAL MICROBIOTA TRANSPLANTATION FOR MILD TO MODERATE ULCERATIVE COLITIS

Abstract BACKGROUND Emerging clinical data shows potential for fecal microbiota transplantation (FMT) in treating ulcerative colitis (UC), though factors affecting clinical response remain poorly defined. Pre-clinical data suggest the role of dietary fiber in enhancing microbial metabolites to mitigate colitis severity. This study aimed to evaluate the role of the prebiotic psyllium in improving the clinical outcomes of FMT for mild to moderate UC, with the long-term goal of enhancing FMT as a therapeutic strategy for UC. METHODS In a randomized, placebo-controlled clinical trial, 32 participants were screened, and 27 adults with mild to moderate UC were enrolled. Baseline fiber intake was assessed through a food frequency questionnaire. Subjects were randomly assigned to receive FMT alone, FMT with daily fiber (10g of psyllium), or a placebo with or without fiber. The primary endpoint was clinical response by Mayo score at week 8. Secondary endpoints included clinical response by partial Mayo (pMayo) score, endoscopic sub-score, and clinical remission. At week 8, participants underwent crossover treatment with clinical evaluation at week 12. The study ended early due to the manufacturer discontinuing fecal microbiota preparation supply. RESULTS Analysis of primary and secondary endpoints in "FMT alone" and "FMT with fiber" groups revealed no statistically significant differences in clinical response (55.56% alone, N=9 vs. 22.22% fiber, N=9, p=0.1686). Participants with low and high dietary fiber consumption had similar response rates, regardless of supplemental fiber. Consequently, we combined the "FMT" and "no FMT" groups, which showed a significantly higher proportion of subjects achieving clinical response in the FMT group as defined by the partial Mayo score (50.00% FMT group (N=18) and 11.1% in the no FMT group (N=9), p=0.0485). A similar trend was observed for clinical response as defined by the total Mayo score and endoscopic sub-score, where the FMT group outperformed the placebo (38.89% FMT, N=18, vs. 11.11% placebo, N=9, p=0.1362). Among the 9 subjects who received FMT at week 0 and exhibited clinical response defined by pMayo, 77.8% (n=7) maintained their response at week 12. Additionally, 2 patients who initially had no response at week 8 achieved a clinical response by week 12. CONCLUSION The results demonstrate a robust effect of single-dose FMT via colonoscopy in a mild to moderate UC cohort. Given the low cohort size, our results lack the statistical power to reveal the clinical impact of fiber supplementation in FMT. Notably, a substantial proportion of initially responsive FMT recipients maintained their clinical response at week 12, indicating the potential for sustained benefits. Microbiome and metabolomic analyses are currently underway to assess the functional impact of dietary fiber in shaping the effectiveness of FMT for UC.

P1064 Upadacitinib is safe and effective in Ulcerative Colitis patients with prior exposure to Tofacitinib

Abstract Background Upadacitinib is a novel selective Janus Kinase (JAK) inhibitor which has recently been approved for use in ulcerative colitis. Clinical trials have rigorous criteria and excluded patients with prior exposure to JAK inhibitors. Given limited real-world effectiveness data we examined outcomes of patients treated with upadacitinib for ulcerative colitis in a real-world population, with a focus on prior tofacitinib exposure. Methods This retrospective, multi-centre study recruited patients commencing upadacitinib for moderate-to-severe ulcerative colitis from September 2022 until March 2023 from 13 Inflammatory Bowel Disease centres across Australia. Clinical, biochemical, endoscopic and intestinal ultrasound outcomes were recorded at baseline, week 8 and week 16. The primary outcome was a comparison between clinical remission using PRO2 definitions (STRIDE II guidelines) in those with prior Tofacitinib exposure compared with Tofacitinib-naïve. Secondary endpoints included clinical response, corticosteroid free clinical remission (CFCR), biochemical response and transmural remission assessed by intestinal ultrasound (IUS). Adverse events in both cohorts were also recorded. Results 152 patients were identified and included (Table 1) – 42 tofacitinib-exposed and 110 tofacitinib-naïve. Complete clinical data was available for all patients at baseline, week 8, and week 16. For the overall cohort, the rate of clinical remission was 20% (30/152) at baseline, 78% (119/152) at week 8 and 85% (129/152) at week 16. In patients with prior tofacitinib exposure, the rate of clinical remission was 23% (10/42) at baseline, 72% (30/42) at week 8 and 86% (36/42) at week 16. In tofacitinib-naïve patients, the rate of clinical remission was 19% (21/110) at baseline, 78% (86/110) at week 8 and 84% (92/110) at week 16 (Figure 1). There was no statistically significant difference in rate of clinical remission at baseline (p=0.23), week 8 (p=0.13) or week 16 (p=0.67). There was no statistically significant difference in clinical response, CFCR, biochemical response or transmural remission by IUS between the cohorts. Adverse events were seen in 40 (26%) patients over the course of 16 weeks follow-up. Most common were acne (12%), rash (4%) and nasopharyngitis (4%). No venous thromboembolism, systemic infection or cardiovascular events were observed. These events were spread evenly among both groups (p=0.37). Conclusion This is the largest real-world study to show that upadacitinib is effective and safe for patients with moderate to severe ulcerative colitis and prior tofacitinib exposure.

P872 PREDICT UC: Optimising Infliximab Induction therapy for Acute Severe Ulcerative Colitis – A Randomised Controlled Trial

Abstract Background The optimal dosing strategy of infliximab (IFX) in Acute Severe Ulcerative Colitis (ASUC) is unknown. We compared intensified and standard dose IFX strategies in ASUC. Methods In this open-label randomised trial (NCT02770040), patients from 13 Australian centres with intravenous steroid-refractory ASUC were randomised to receive a first dose of 10mg/kg or 5mg/kg IFX in a 1:2 ratio. Patients in the 10mg/kg group (intensified induction [II]) received a second dose at day 7 or earlier at time of non-response; all 5mg/kg patients were re-randomised 1:1 to standard (SI) or accelerated induction (AI), which produced three induction groups: II, SI and AI. SI patients received 5mg/kg at week 0, 2 and 6, with an extra 5mg/kg dose before day 7 if non-response. AI patients received 5mg/kg at week 0, 1 and 3, with the week 1 dose increased to 10mg/kg and given earlier if non-response. Primary outcome: clinical response by day 7 (reduction in Lichtiger score to <10, with decrease of ≥3 points and improvement in rectal bleeding and stool frequency to ≤4/day). Secondary outcomes compared induction regimens until month 3. Analysis was by intention to treat. Results Between July 2016 & September 2021, 138 patients were randomised; 46 received a first IFX dose of 10mg/kg and 92 received 5mg/kg. Primary outcome: day 7 clinical response was observed in 65% (30/46) of 10mg/kg vs 61% (56/92) of 5mg/kg patients (P=0.76). In the 5mg/kg group, the rate of day 7 response was numerically lower in those with albumin <25g/L vs ≥25g/L [47% (15/32) vs 68% (41/60), P=0.07]. No difference in clinical response was observed in the 10mg/kg group when stratified by albumin [64% (9/14) vs 66% (21/32) P>0.99]. There was no difference in time to clinical response, change in Lichtiger score or CRP from baseline to day 7. Two patients who received 10mg/kg IFX underwent colectomy in the first 7 days vs 0 in the 5mg/kg group (P=0.21). Comparison of induction regimens (II, SI & AI): no difference in clinical remission rates between weeks 2 and 6 were observed. AI and II groups had higher rates of combined clinical and biochemical remission compared to SI between weeks 2 and 6 (P=0.042). At 3 months, there was no difference in rates of endoscopic and steroid-free remission, as well as rates of colectomy (II 7%; SI 12%; AI 19%, P=0.20). Conclusion In steroid-refractory ASUC, a first dose of 10mg/kg or 5mg/kg IFX achieved similar clinical response rates by day 7. Patients receiving intensified or accelerated induction achieved clinical and biochemical remission earlier compared to standard induction; however, outcomes at three months were similar. Patients with a lower albumin may benefit from proactive intensified dosing strategies.

1724 Age is just a number: Cardiac resynchronisation therapy in older patients has comparable outcomes to those that are younger

Abstract Introduction Older people may be less likely to receive cardiac resynchronisation therapy (CRT) for the management of chronic heart failure. We aimed to describe differences in clinical response, complications, and subsequent outcomes following CRT implantation in older patients when compared to those that were younger. Methods We conducted a retrospective cohort study of consecutive patients implanted with CRT between March 2008 and July 2017. We recorded complications, symptomatic and echocardiographic response, hospitalisations for heart failure, and all-cause mortality comparing patients aged <70, 70-79, and ≥80 years. Results During the study period, 574 patients (median age 76 years [IQR 68-81], 73.3% male) received CRT. Patients aged ≥80 years had worse symptoms at baseline and were more likely to have co-morbidities. Although the provision of guideline-directed medical therapy for heart failure was less optimal in those ≥80 years old, left ventricular function was similar at baseline. Older patients were less likely to receive CRT-defibrillators (which were twice as likely to require generator replacement) compared to CRT-pacemakers. Complications were infrequent and not more common in older patients. Age was not a predictor of symptomatic or echocardiographic response to CRT (67.2%, 71.2%, and 62.6% responders in patients aged <70, 70-79, and ≥80 years, respectively; p=0.43) and time to first heart failure hospitalisation was similar across all groups (p=0.28). Finally, estimated 10-year survival was lower for older patients (49.9%, 23.9%, and 6.8% for patients aged <70, 70-79, and ≥80 years, respectively; p<0.001). Conclusions The benefits of CRT were consistent in selected older patients (≥80 years) despite a greater burden of co-morbidities and less optimal provision of guideline-directed medical therapy. These findings support the use of CRT in an aging population.

Management of Immune Thrombotic Thrombocytopenic Purpura without Therapeutic Plasma Exchange: Analysis of Efficacy and Safety Data

Background: Immune thrombotic thrombocytopenic purpura (iTTP) is a rare, life-threatening autoimmune disorder caused by ADAMTS13 deficiency. Caplacizumab, an anti-VWF nanobody, is approved for iTTP treatment, reducing the need for therapeutic plasma exchange (TPE) and improving platelet recovery and survival. Methods: We conducted a retrospective study on 42 acute iTTP cases in Austria and Germany, treated with a modified regimen aimed at avoiding TPE if platelet count increased post-first caplacizumab dose. An extensive efficacy and safety analysis of this approach was performed, in comparison with a control group of 59 patients with iTTP, receiving frontline caplacizumab treatment with TPE and immunosuppression (standard of care, SOC). The main outcome was time to platelet count normalization. Secondary outcomes included clinical response, exacerbation, refractory iTTP, and iTTP-related deaths. Retrospective safety assessments with evaluation of treatment emergent adverse events (TEAE) were performed in both cohorts. Results: The median time to platelet count normalization was similar between the two cohorts (3 and 4 days; P = 0.31, see Figure 1). There were no significant differences in clinical response, exacerbations, refractoriness, or iTTP-related deaths (see Table 1). Four patients did not respond to the first dose of caplacizumab, and TPE was initiated. Cytomegalovirus infection, HIV/hepatitis B co-infection, and ovarian teratoma may have hindered immediate treatment response. Platelet count doubling and median platelet count change after first caplacizumab dose were unaffected by TPE. The median time to LDH normalization was 11 days in the TPE-free cohort. During overall follow-up at least one adverse event (TEAE) was observed in 11 patients (26.2%) in the TPE-free group and 15 patients (25.4%) in the SOC group (excluding adverse events of iTTP that were evaluated as outcome parameters) (see Table 1). There was one TTP-related death reported in the SOC group (1.7%). The cause of death in this patient was cerebral ischemia due to multiple strokes. Serious adverse events associated with therapeutic plasma exchange were observed in 3 patients (5.1%) exclusively in the SOC cohort. These included (1) in-hospital cardiac arrest (IHCA), (2) generalized seizure and supraventricular tachycardia and (3) a transfusion reaction with hypotension, rigors, pruritus and exanthema. Bleeding complications were reported without a significant difference and mainly comprised gingival bleeding and epistaxis. Two patients in the TPE-free cohort (4.8%) experienced major bleeding events, namely subdural hematoma requiring surgical intervention and gastrointestinal bleeding with mass transfusion. Spontaneous subdural hematoma occurred in one patient after 20 days of caplacizumab treatment. Gastrointestinal bleeding from a colon diverticulum occurred in another patient after a clinical response and resulted in a significant drop in hemoglobin and thrombocytes. Gastrointestinal bleeding worsened with concomitant factor XIII deficiency, which was reconstituted intravenously in addition to mass transfusion. Conclusion: Caplacizumab and immunosuppression, without TPE, rapidly controlled microvascular thrombosis and achieved a sustained clinical response in iTTP. The efficacy was similar to the control group, which received SOC. Standard iTTP treatment with TPE may lead to a prolonged hospital stay, including admission to the ICU, multiple sessions of daily TPE with associated risks, and the associated costs of plasma, equipment, nursing care, and medical supervision. The number of patients experiencing critical adverse events was comparable between groups. Bearing all restrictions of a retrospective cohort in mind, we did not identify a critical safety signal for TPE-free iTTP-treatment. However, TPE itself resulted in three life-threatening adverse events in the SOC cohort, including an in-hospital cardiac arrest. In conclusion, omitting TPE appears to be a viable choice for acute iTTP management that may reduce treatment burden without compromising patient outcomes or safety.

Outcomes following cardiac resynchronisation therapy in older people.

Older patients may be less likely to receive cardiac resynchronisation therapy (CRT) for the management of heart failure. We aimed to describe the differences in clinical response, complications, and subsequent outcomes following CRT implantation compared to younger patients. We conducted a retrospective cohort study of unselected, consecutive patients implanted with CRT devices between March 2008 and July 2017. We recorded complications, symptomatic and echocardiographic response, hospitalisation for heart failure, and all-cause mortality comparing patients aged <70, 70-79 and ≥ 80years. Five hundred and seventy-four patients (median age 76years [interquartile range 68-81], 73.3% male) received CRT. At baseline, patients aged ≥80years had worse symptoms, were more likely to have co-morbidities, and less likely to be receiving comprehensive medical therapy, although left ventricular function was similar. Older patients were less likely to receive CRT-defibrillators compared to CRT-pacemakers. Complications were infrequent and not more common in older patients. Age was not a predictor of symptomatic or echocardiographic response to CRT (67.2%, 71.2% and 62.6% responders in patients aged <70, 70-79 and ≥ 80years, respectively; P = 0.43), and time to first heart failure hospitalisation was similar across age groups (P = 0.28). Ten-year survival was lower for older patients (49.9%, 23.9% and 6.8% in patients aged <70, 70-79 and ≥ 80years, respectively; P < 0.001). The benefits of CRT on symptoms and left ventricular function were not different in older patients despite a greater burden of co-morbidities and less optimal medical therapy. These findings support the use of CRT in an ageing population.

323 Forskolin-induced swelling measured in patient-derived intestinal organoids reflects differences in clinical response to dual- and triplemodulator therapy

323 Forskolin-induced swelling measured in patient-derived intestinal organoids reflects differences in clinical response to dual- and triplemodulator therapy

Immune thrombotic thrombocytopenic purpura in older patients: Results from the Spanish TTP Registry (REPTT).

Immune thrombotic thrombocytopenic purpura (iTTP) is an ultra-rare disease that seldom occurs in the elderly. Few reports have studied the clinical course of iTTP in older patients. In this study, we have analysed the clinical characteristics at presentation and response to therapy in a series of 44 patients with iTTP ≥60 years at diagnosis from the Spanish TTP Registry and compared them with 209 patients with <60 years at diagnosis from the same Registry. Similar symptoms and laboratory results were described in both groups, except for a higher incidence of renal dysfunction among older patients (23% vs. 43.1%; p = 0.008). Front-line treatment in patients ≥60 years was like that administered in younger patients. Also, no evidence of a difference in clinical response and overall survival was seen in both groups. Of note, 14 and 25 patients ≥60 years received treatment with caplacizumab and rituximab, respectively, showing a favourable safety and efficacy profile, like that observed in patients <60 years.

Ceftazidime/avibactam experience in tertiary hospital in Türkiye

Aims: Real-life experience with ceftazidime/avibactam in the treatment of multidrug-resistant Klebsiella pneumoniae is still limited. This retrospective study aims to evaluate the efficacy of ceftazidime/avibactam in the treatment of critically ill patients with infections due to carbapenem-resistant pathogens. Methods: In our study, patients who were hospitalized in the ICUs of our hospital for more than three days between 01-01-2022 and 31-12-2022, who had only ceftazidime/avibactam susceptibility growth and were started on ceftazidime/avibactam treatment were retrospectively analyzed. 38 patients older than 18 years of age were included in the study. Results: Pneumonia was the most common cause of hospitalization in the ICU, followed by cerebrovascular events and internal diseases, respectively. The mean time from taking the culture samples to obtaining the laboratory results was 4.6 ±1.46 days. After the culture result was confirmed by the laboratory, the mean time between the patient's consultation by infection diseases specialist and initiation of treatment was 1.7±1.3 days. Patients received a mean of 10.6 ±4.63 days of CAZ-AVI treatment as monotherapy (57.9%) or combined therapy (42.1). Clinical response was obtained in 52.6% of the patients, and microbiological response was obtained in 63.2% of the patients. The 90-day all-cause mortality rate of patients receiving CAZ-AVI was 60.5% (n=23), and the mortality rate attributed to 14-day infection was 52.17%. Side effects developed in 18.4% of the patients. None of the developed side effects were such as to require discontinuation of treatment. There was no statistical difference in clinical response and microbiological response in patients receiving combination therapy and monotherapy. Mortality was significantly lower in patients receiving CAZ-AVI monotherapy (p&lt;0.05). Conclusion: We attribute our low clinical success to the late initiation of treatment due to drug reimbursement criteria. Therefore, we think that CAZ-AVI treatment should be started empirically and as soon as possible. We think that our study is valuable in terms of showing that CAZ-AVI treatment should be given in empirical treatment.

438 Potentially greater efficacy with CBP-201 for adults with severe vs. moderate atopic dermatitis at baseline: subgroup analyses from the WW001 phase 2 randomized trial

Abstract CBP-201 is a next-generation monoclonal antibody targeting the IL-4Rα subunit. Rapid efficacy with CBP-201 was demonstrated in global phase 2 (WW001) and China-only pivotal trials (CN002) in patients with moderate-to-severe atopic dermatitis (AD). Previous studies of AD therapy demonstrated similar efficacy between moderate and severe disease, with a trend toward greater improvement in moderate patients. It is unknown whether there are differences in clinical response to CBP-201 with moderate vs.severe AD. We report post hoc efficacy analyses at Week 16 with CBP-201 300 mg from WW001 in baseline severity subgroups, based on validated Investigator Global Assessment (vIGA™) scores of 3 (moderate) and 4 (severe). In WW001 (NCT04444752), adults with moderate-to-severe AD were enrolled in a RDBPC 16-week trial of subcutaneous CBP-201 or placebo. For post hoc analysis, data for 300 mg every 2- and 4-week dose regimens were pooled. Investigators assessed AD severity using Eczema Area and Severity Index (EASI), SCORing AD (SCORAD), percent Body Surface Area (BSA) of AD involvement and vIGA. Patient-reported outcomes were assessed with the Dermatology Life Quality Index (DLQI) and Patient Oriented Eczema Measure (POEM). Least squares mean (LSM) score changes were analysed using ANCOVA modeling (including treatment, baseline score and baseline vIGA), with missing data interpolated by last observation carried forward. Responder endpoints were analysed using Clopper–Pearson methodology and, for missing values, nonresponder imputation. P-values are for CBP-201 vs. placebo, per baseline severity subgroup, at Week 16. At baseline, 113 patients had moderate AD (n = 74 CBP-201, n = 39 placebo) and 56 patients had severe AD (n = 39 CBP-201, n = 17 placebo). Baseline EASI scores were lower in the moderate subgroup [mean (SD): CBP-201, 21.5 (7.0); placebo, 22.2 (6.3)] vs. the severe subgroup [CBP-201, 33.6 (11.9); placebo, 31.9 (10.8)]. In both the moderate and severe AD subgroups, significant improvements with CBP-201 vs. placebo were observed. Except for the proportion of patients achieving vIGA 0/1, numerically greater CBP-201 responses were observed in patients with severe vs. moderate AD at Week 16; placebo responses were comparable per subgroup. In the severe and moderate subgroups, LSM SCORAD scores decreased by −42.8% (severe) and −29.8% (moderate), and LSM percent BSA decreased by −29.8% and −17.3%, respectively. Clinically meaningful 2-point improvement in vIGA was reported for 48.7% and 27.0% of patients with severe and moderate AD, respectively. The proportions of patients achieving vIGA 0/1, with 2-point improvement, were 20.5% and 27.0% with severe and moderate AD, respectively. Numerically greater proportions of patients with severe vs. moderate AD experienced EASI responses with CBP-201: EASI-50, 66.7% vs. 54.1%; EASI-75, 53.8% vs. 39.2%; EASI-90, 28.2% vs. 23.0%. Patients with severe vs. moderate AD reported greater improvements in patient reported outcomes with CBP-201: DLQI, −8.7 vs. −7.0; POEM, −12.5 vs. −8.7. Clinically meaningful improvements were observed in patients with AD with either moderate or severe AD after 16 weeks of treatment with CBP-201 300 mg at either 2- or 4-week dosing. There were no differences noted between moderate and severe patients in the placebo treatment group. In most severity readouts, greater proportions of patients with AD with severe disease on study entry experienced clinically meaningful improvements with CBP-201. In future CBP-201 trials, a more severe AD population needs to be examined to determine if this same observation is also noted. Collectively, the WW001 findings support further investigation of CBP-201, at both the 2- and 4-week dosing schedules enrolling larger numbers of moderate and severe patients with AD and with prespecified analyses by baseline AD severity.

Nb-UVB and PUVA therapy in treating early stages of Mycosis Fungoides: A single-center cross-sectional study.

Mycosis fungoides (MF) and Sezary Syndrome are the most common forms of cutaneous T-cell lymphoma. Early-stage MF is known to have an indolent behavior, and the EORTC guidelines recommend treating patients with skin-directed therapies, such as phototherapy, instead of systemic therapies. Phototherapy is a popular therapeutic option, with two commonly used light sources-PUVA and narrow band-nb UVB. PUVA is less commonly used due to its potential carcinogenic role, but it has systemic effects, while nb-UVB has mostly skin-limited effects. There is ongoing debate regarding the role of UVB light, and in 2021, the Cutaneous Lymphoma Italian Study Group reached a consensus on technical schedules for NB-UVB and PUVA for MF. This study aims to analyze and compare the efficacy of the two phototherapy options in treating early-MF patients. The study included patients diagnosed with stage IA/B MF in the last 10 years, who had at least 12 months of follow-up data and a minimum of 24 phototherapy sessions (PUVA or nb UVB) and treated with topical steroids apart from phototherapy. Results showed that the two phototherapy options were similarly effective in treating early MF, with no significant differences in clinical response, although PUVA was associated with more adverse effects. The study provides valuable insights into the use of phototherapy in early MF, and the results can be used to guide treatment decisions and improve patient outcomes.

Dose-adjusted EPOCH-R vs. R-CHOP in frontline management of Waldeyer's ring diffuse large B-cell lymphoma: a retrospective study from a single institution.

To compare the efficacy and safety of dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin plus rituximab (DA-EPOCH-R) with standard rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) in Waldeyer's ring diffuse large B-cell lymphoma (WR-DLBCL) at a single institution. This retrospective study included 115 newly diagnosed patients with WR-DLBCL, of whom 68 patients received R-CHOP, and 47 patients received DA-EPOCH-R as their first-line treatment. The baseline features of the two groups were well balanced using a 1:1 propensity score matching method, and a total of 84 cases were obtained, including respective 42 cases in the R-CHOP and DA-EPOCH-R groups, for further survival and prognosis analysis. The primary objectives included progression-free survival (PFS) and overall survival (OS). During a median follow-up of 45 months, there were nine (21.4%) deaths in the R-CHOP group and two (4.8%) in the DA-EPOCH-R group. Kaplan-Meier analysis showed statistically significant improvements in PFS and OS in patients with DA-EPOCH-R compared with those treated with R-CHOP (log-rank test, P = 0.025 and P = 0.035, respectively). The 2-year PFS and OS rates in the DA-EPOCH-R group were 90.1% (95% confidence interval [CI]: 81.4-99.8%) and 95.2% (95% CI: 89.0-100.0%), respectively, and 80.5% (95% CI: 69.3-93.6%) and 90.5% (95% CI: 52.8-99.8%) in the R-CHOP group. Patients without B symptoms and elevated lactate dehydrogenase levels had a higher PFS in the DA-EPOCH-R group, with P values of 0.038 (hazard ratio [HR]: 0.11; 95% CI: 0.01-0.88) and 0.042 (HR: 0.19; 95% CI: 0.04-0.94), respectively. There were no statistically significant differences in clinical responses and treatment-related toxicities between the two groups. Compared with patients received R-CHOP, those treated by DA-EPOCH-R had superior PFS, OS, and controlled toxicity in patients with WR-DLBCL.