Current triplet regimens associating therapeutic plasma exchange (TPE), immunosuppression with corticosteroids and rituximab, and caplacizumab have dramatically improved the outcome of immune-mediated thrombotic thrombocytopenic purpura (iTTP). However, nearly half of the patients require extended caplacizumab treatment (i.e., > 30 days) due to persistent ADAMTS13 deficiency, raising cost and tolerance concerns. Therefore, we investigated whether anti-ADAMTS13 antibodies titer and their trajectory during the acute phase of the disease could predict ADAMTS13 improvement (i.e., activity ≥ 20% before day-30 post-TPE). From a cohort of 286 patients receiving the triplet regimen, we identified on diagnosis a cut-off value for anti-ADAMTS13 IgG antibodies of 90.5 U/mL, with a modest discriminating ability (AUC: 0.57) for predicting long-term response, precluding its use to guide therapeutic strategies. Nonetheless, the analysis of anti-ADAMTS13 IgG antibodies titer trajectory from diagnosis revealed that the proportion of iTTP patients with ADAMTS13 activity improvement was higher in patients who decreased (Dec+) their antibodies titer within the 7-14 days interval post-TPE compared to those without decrease (Dec-) (65% vs. 25% of cases, respectively, p < 0.001), a finding confirmed in a validation cohort (N = 51). These results highlight the possibility of intensifying immunosuppression in an early period post-TPE to shorten time to ADAMTS13 activity recovery. Close monitoring of anti-ADAMTS13 antibodies titer may guide immunomodulation strategies, including additional courses of B-cell depleting agents when appropriate.
9092 Background: Alectinib is a standard of care option in advanced ALK-rearranged (ALK+) non-small cell lung cancer (NSCLC) patients (pts), with efficacy established by phase 3 trials, in first-line and beyond. There are few efficacy data in unselected populations. Methods: The objective of this study was to evaluate the efficacy of alectinib in real-world setting. All ALK+ advanced NSCLC pts initiating alectinib, between December 13, 2017 (date of access in France) and June 27, 2020, whatever the line, were included in explore ALK study. Patient characteristics, alectinib duration of treatment (DOT), progression-free survival assessed locally (rwPFS), overall survival (OS) according to the prescription line of alectinib, the presence of brain metastases at alectinib initiation, response rate and tolerance were collected from the medical files. Results: The analysis included 223 pts: 46.2% were men, 84.7% had no smoking history or were former smokers, median age was 59 (22-101) years and 95% were adenocarcinomas. Alectinib was initiated as first-line treatment in 119 pts, with a PS of 0/1/>1 in 42%/31%/27% of cases, a median number of metastatic sites of 2 (cerebral, hepatic, bone in 33%, 24% and 32% of cases). In first-line setting, after a median follow-up of 33.7 months (95%CI, 32.2-37.5), the median of rwPFS and DOT were 28.1 (95%CI, 20.7-40.4) and 26.9 (95%CI, 20.2-31.3) months, respectively. The median OS was not reach (NR), the 3-year OS rate was 72.1%. The rwPFS was not significantly different depending on whether or not the patient has brain metastases, 28.1 (95% CI, 14.5-NR) and 30.5 (85% CI, 18.9-40.4) months, respectively. The best response was complete (CR), partial (PR) and stable (SD) in 21%, 58% and 17%. The cerebral response, evaluable in 30/39 of the pts, was CR, PR and SD in 26%, 46% and 23% respectively; 33% of pts had a grade 3 adverse event, resulting in a temporary interruption of treatment in 7.6% of cases and a permanent discontinuation in 5.9% of cases. At the time of progression, 48.1% of pts had a new biopsy (66% of tissue biopsy). Efficacy data for alectinib prescribed as second line and above are summarized in the table. Conclusions: In this large real-world, cohort of unselected advanced ALK+ NSCLC pts, alectinib initiated in 1 st -line or beyond provides similar efficacy and safety results as obtained in phase III clinical trials. [Table: see text]
618 Background: Muscle metastases (MM) are among rare secondary locations in renal cell carcinoma (RCC). Current guidelines do not provide specific advice on the management of these patients. There is a lack of scientific literature on the subject, mainly based on case reports or small retrospective monocentric cohorts. To date, therefore, there remains uncertainty about the clinical history, prognosis, and appropriate management of patients with MM. Methods: ARTEMIS is an ambispective national French multicenter, non-interventional study. It was opened to patients with metastatic RCC who had MM. The study was designed to assess overall survival (OS), progression-free survival (PFS), describe diagnostic and treatment modalities, and treatment-related serious adverse events in case of local treatments (TR-SAEs). Results: Median follow-up was 74.4 months IC95% [38.7-84.1]. The 146 enrolled patients were 73.6% male, with a median age of 57.6 years at diagnosis. They were initially diagnosed with stage IV RCC for 40.4% of them and had a favorable (36.2%), intermediate (45.7%), or poor (18.1%) IMDC risk score at the onset of metastases. Initially, metastases were mainly located in the lungs (55.5%), lymph nodes (26.7%), and bones (24.0%). Patients had a history of partial or total nephrectomy in 78.8% of cases. There were 30.0% of patients with synchronous MM. The median times from initial diagnosis or metastatic status to MM discovery were 25.5 [16.8-35.7] months and 8.4 [5.0-13.5] months, respectively. The majority (69.0%) of MM were discovered on conventional injected CT scans, whereas 8.3% were diagnosed clinically. Survival data are displayed on the table. Thirty-seven (25.3%) patients received local treatment of their MM which consisted of: external radiotherapy (48.6%), surgery (27.0%), cryotherapy (27.0%), stereotactic radiotherapy (5.4%), embolization (2.7%). Among them, local treatments prevented local relapse of MM in 28 patients (75.7%). Local TR-SAEs were seen in two patients (5.4%). Conclusions: ARTEMIS is the largest published cohort describing the disease history of patients with RCC suffering from MM. To our knowledge, this is the first study reporting the diagnostic and treatment modalities, also survival data. Despite its low incidence, the issue of these patients is not so rare in physicians’ practice. This work thus allows a greater understanding of clinical features and treatment of this pathology. [Table: see text]