Blood advances最新文献

Activated protein C (APC) is a pleiotropic plasma protease with diverse functions derived from its anticoagulant, anti-inflammatory, and cytoprotective activities. The selective uncoupling and/or modulation of these APC activities by antibodies may have therapeutic benefit in diseases such as traumatic bleeding, hemophilia, sepsis, and ischemia. TPP-26870 is an antibody that targets a non-active site of APC for the selective modulation of APC activities. To optimize the potency of TPP-26870, variants with single amino acid mutation in the complementarity-determining regions (CDRs) were screened, and 21 variants with improved KD were identified. Interestingly, the affinity maturation of TPP-26870 did not merely generate a panel of variants with higher potency in functional assays. Functional data demonstrated that the pleiotropic functions of APC were very sensitive to epitope-CDR interactions. Single amino acid mutations within the CDRs of TPP-26870 were sufficient to elicit divergent antagonistic and agonistic effects on the various APC functional activities. These include prolonged in vitro APC plasma half-life, increased inhibition of anticoagulant activity, and agonistic enhancement of histone H3 cleavage, while having less impact on PAR1 cleavage in comparison to TPP-26870. This study illustrates that APC is highly sensitive to non-active site targeting that can lead to unpredictable changes in its activity profile of this pleiotropic enzyme. Further, this study demonstrates the ability to modify APC functions to advance the potential development of APC targeted antibodies as therapeutics for the treatment of diseases including trauma bleeding, hemophilia, ischemia, and sepsis.

To examine activity of ibrutinib in steroid-refractory chronic GVHD (SR-cGVHD) after FDA approval, we conducted a multicenter retrospective study. Data were standardly collected (N=270 from 19 centers). Involved organs included skin (75%), eye (61%), mouth (54%), joint/fascia (47%), GI (26%), lung (27%), liver (19%), genital (7%), other (4.4%). NIH severity was mild in 5.7%, moderate 42%, severe 53%. 39% had overlap subtype. KPS was ≥ 80% in 72%. Median prednisone (mg/kg) was 0.21 (0-2.27). Ibrutinib was started at median of 18.2 months after cGVHD onset and in earlier lines of therapy (2nd line: 26%, 3rd: 30%, 4th: 21%, 5th: 9.6%, 6th: 10%, 7th or higher: 1.2%)). Among evaluable subjects, the 6 month NIH overall response rate (CR/PR) was 45% (PR 42%, CR 3%). Median duration of response was 15 months (range 1-46). Liver involvement had association with 6 month ORR (multivariate (MVA) OR 5.49 (95% CI 2.3-14.2, p <0.001). Best overall response was 56%, with most (86%) achieving by 1-3 months. With median follow up for survivors of 30.5 months, FFS was 59% (53-65%) at 6 months and 41% (36-48%) at 12 months. On MVA, increased age (HR 1.01, 95% CI 1.0-1.02, p=0.033), higher baseline prednisone (HR 1.92, 1.09-3.38, p=0.032), and lung involvement (HR 1.58, 1.1-2.28, p=0.016) had worse FFS. Ibrutinib discontinuation was most commonly due to progressive cGVHD (44%) or toxicity (42%). These data support that ibrutinib has activity in SR-cGVHD, provide new insight into factors associated with response and FFS, and demonstrate the toxicity profile associated with discontinuation.

The Children's Oncology Group study AALL1931 investigated the efficacy and safety of recombinant Erwinia asparaginase (JZP458) in patients with acute lymphoblastic leukemia/lymphoblastic lymphoma and hypersensitivity reactions/silent inactivation to Escherichia coli-derived asparaginases. Each pegylated Escherichia coli asparaginase dose remaining in a patient's treatment plan was replaced by intramuscular (IM) or intravenous (IV) JZP458 (6 doses) administered Monday/Wednesday/Friday (MWF). Three IM cohorts (1a [25 mg/m2 MWF], n=33; 1b [37.5 mg/m2 MWF], n=83; 1c [25/25/50 mg/m2 MWF], n=51) and 1 IV cohort (25/25/50 mg/m2 MWF, n=62) were evaluated. The proportion (95% confidence interval) of patients maintaining nadir serum asparaginase activity (NSAA) levels ≥0.1 IU/mL at the last 72 (primary endpoint) and 48 hours during course 1 was 90% (81, 98) and 96% (90, 100) in IM cohort 1c, respectively, and 40% (26, 54) and 90% (82, 98) in the IV cohort. Population pharmacokinetic modeling results were comparable with observed data, predicting the vast majority of patients would maintain therapeutic NSAA levels when JZP458 is administered IM or IV 25 mg/m2 every 48 hours, or IM 25/25/50 mg/m2 MWF, or with mixed administration of IM and IV (IV/IV/IM 25/25/50 mg/m2 MWF). Drug discontinuation occurred in 23% and 56% of patients in the IM and IV cohorts, respectively; 13% and 33% due to treatment-related adverse events (mainly allergic reactions and pancreatitis). JZP458 achieves therapeutic NSAA levels via multiple IM and IV dosing schedules based on a combination of observed and modeled data with a safety profile consistent with other asparaginases. Clinicaltrials.gov Identifier: NCT04145531.

CPX-351 has been approved for patients with therapy-related acute myeloid leukemia (t-AML) or AML with myelodysplasia-related changes (MRC-AML). No extensive data are available on MRD and long-term clinical outcome using CPX-351 in AML in real-life. We retrospectively collected data from 168 patients in 36 centers in France and Italy who had received one or two cycles of induction with CPX-351. All patients were older than 18 years and had newly diagnosed, untreated t-AML or MRC-AML. With a median follow-up of 3 years, median OS was 13.3 months. Median OS was 20.4 months vs. 12.9 months for patients with MRD below or above 10-3, respectively (p=0.006). In a multivariate analysis, only MRD >10-3 was associated with a poorer OS (hazard ratio [HR]=2.6, 95% CI 1.2-5.5, p=0.013). We also observed a trend towards a better median OS in patients who underwent HSCT with MRD <10-3 (not reached vs. 26.0 months, p=0.06). Achievement of MRD negativity contributed to the improvement of OS in the overall population and, maybe, in transplanted patients. These data provide the rationale for the two ongoing studies evaluating CPX-351 vs. 7+3 in non-MRC-AML and non-t-AML using MRD as the primary endpoint for ALFA-2101 phase II clinical trial and event-free survival for AMLSG 30-18 phase III clinical trial.