Safety and efficacy of long-term emicizumab prophylaxis in hemophilia A with factor VIII inhibitors: A phase 3b, multicenter, single-arm study (STASEY).

Background: The bispecific monoclonal antibody emicizumab bridges activated factor IX and factor X, mimicking the cofactor function of activated factor VIII (FVIII), restoring hemostasis. Objectives: The Phase 3b STASEY study was designed to assess the safety of emicizumab prophylaxis in people with hemophilia A (HA) with FVIII inhibitors. Methods: People with HA received 3 mg/kg emicizumab once weekly (QW) for 4 weeks followed by 1.5 mg/kg QW for 2 years. The primary objective was the safety of emicizumab prophylaxis, including incidence and severity of adverse events (AEs) and AEs of special interest (thrombotic events [TEs] and thrombotic microangiopathies). Secondary objectives included efficacy (annualized bleed rates [ABRs]). Results: Overall, 195 participants were enrolled; 193 received emicizumab. The median (range) duration of exposure was 103.1 (1.1-108.3) weeks. Seven (3.6%) participants discontinued emicizumab. The most common AEs were arthralgia (n = 33, 17.1%) and nasopharyngitis (n = 30, 15.5%). The most common treatment-related AE was injection-site reaction (n = 19, 9.8%). Two fatalities were reported (polytrauma with fatal head injuries and abdominal compartment syndrome); both were deemed unrelated to emicizumab by study investigators. Two TEs occurred (myocardial infarction and localized clot following tooth extraction), also deemed unrelated to emicizumab. The negative binomial regression model-based ABR (95% confidence interval) for treated bleeds was 0.5 (0.27-0.89). Overall, 161 participants (82.6%) had zero treated bleeds. Conclusions: The safety profile of emicizumab prophylaxis was confirmed in a large population of people with HA with FVIII inhibitors and no new safety signals occurred. The majority of participants had zero treated bleeds.

Systemic thromboembolic complications after laparoscopic splenectomy for idiopathic thrombocytopenic purpura in comparison to open surgery in the absence of anticoagulant prophylaxis.

BACKGROUND: Idiopathic thrombocytopenic purpura (ITP) in adults has a chronic course and may necessitate splenectomy. The current study was undertaken to study the systemic thromboembolic complications of laparoscopic splenectomy (LS) versus open splenectomy (OS) in patients with ITP at two large referral hospitals. PATIENTS AND METHODS: We conducted a retrospective analysis of 49 patients who underwent splenectomy (21 LS and 28 OS) for primary/relapsing refractory ITP between June 1995 and November 2004. Clinically and/or radiologically confirmed deep venous thrombosis (DVT) and/or pulmonary embolism (PE) were assessed within 2 weeks before and after splenectomy. None had prophylactic anticoagulants immediately after surgery. Follow up of those who developed complications continued for at least 2 additional years to assess for contributing factors that may have been masked at the time of occurrence. RESULTS: Two (9.5%) LS group had acute PE within 5 days of LS and their platelet count reached 500A103/I(1/4)L within 4 days and 1000A103/I(1/4)L within 7 days after surgery. Three conversions to OS occurred; none had VTE. DVT occurred in 3 patients (10.7%) in the OS group; none were life threatening. There were no deaths. CONCLUSION: Life-threatening venous thromboembolic events are serious complications after LS and OS for ITP patients if prophylactic anticoagulants are not administered. Patients at risk are those who both have an exponential rise of the platelet count, although factors other than the platelet count may be contributing in OS. Postsplenectomy, ITP should be considered as a thrombophilic condition and studies of additional measures to prevent such events are warranted.

Defective gammadelta T-cell function and granzyme B gene polymorphism in a cohort of newly diagnosed breast cancer patients.

OBJECTIVE: The purpose of this study was to examine the antitumor immune function of gammadelta T cells and to scan the granzyme B gene for the known single nucleotide polymorphism in breast cancer patients and normal controls. MATERIALS AND METHODS: Levels, cytotoxicity, and functional capacity of gammadelta T cells in peripheral blood mononuclear cells were assessed by flow cytometry, (51)Cr release, and ELISpot assays, respectively. Furthermore, sequence based typing was adopted to screen for granzyme B gene polymorphism. RESULTS: We have found that the frequency and function of gammadelta T cells are reduced both in peripheral blood mononuclear cells of 30 newly diagnosed breast cancer patients (2 [1.2, 3]), compared with 38 normal controls (3.2 [2.5, 5.7]) (p=0.02). In addition, resting gammadelta T cells from breast cancer patients produced significantly more interleukin-6 and tumor necrosis factor-alpha than normal controls. Moreover, ex vivo stimulation of gammadelta T cells with zoledronic acid and interleukin-2 compensated in part for this deficiency, as it stimulated the proliferation, cytokine production, and enhanced the expression of messenger RNA of granzyme B. Interestingly, when the known granzyme B gene polymorphism was screened, we found the prevalence of the mutated genotype RAH/RAH to be significantly (p<0.017) associated with breast cancer patients (14.30%) compared with normal donors (1.40%). Cytotoxicity exerted by gammadelta T cells on Daudi and MCF-7 was significantly higher in donors with the wild-type QPY/QPY (50%) compared with donors with RAH/RAH (21%). CONCLUSIONS: Our data suggest that reduction in the proportion of gammadelta T cells and granzyme B gene polymorphism leads to defective immune function in breast cancer patients. Treatment with zoledronic acid amend partially this fault. Further studies of gammadelta T cells function and granzyme B gene polymorphism in cancers, as well as the potential therapeutic use of zoledronic acid are warranted.