Long-term treatment with rilzabrutinib in patients with immune thrombocytopenia

ABSTRACT

Immune thrombocytopenia (ITP) is an autoimmune disease associated with autoantibody-mediated platelet destruction and impaired platelet production, resulting in thrombocytopenia and a predisposition to bleeding. The ongoing, global phase 1/2 study showed that rilzabrutinib, a Bruton tyrosine kinase inhibitor specifically developed to treat autoimmune disorders, could be an efficacious and well-tolerated treatment for ITP. Clinical activity, durability of response, and safety were evaluated in 16 responding patients who continued rilzabrutinib 400 mg twice daily in the long-term extension (LTE) study. At LTE entry, the median platelet count was 87 × 109/L in all patients, 68 × 109/L in those who had rilzabrutinib monotherapy (n = 5), and 156 × 109/L in patients who received concomitant ITP medication (thrombopoietin-receptor agonists and/or corticosteroids, n = 11). At a median duration of treatment of 478 days (range, 303-764), 11 of 16 patients (69%) continued to receive rilzabrutinib. A platelet count of ≥50 × 109/L was reported in 93% of patients for more than half of their monthly visits. The median percentage of LTE weeks with platelet counts ≥30 × 109/L and ≥50 × 109/L was 100% and 88%, respectively. Five patients discontinued concomitant ITP therapy and maintained median platelet counts of 106 × 109/L at 3 to 6 months after stopping concomitant ITP therapy. Adverse events related to treatment were grade 1 or 2 and transient, with no bleeding, thrombotic, or serious adverse events. With continued rilzabrutinib treatment in the LTE, platelet responses were durable and stable over time with no new safety signals. This trial is registered at www.clinicaltrials.gov as #NCT03395210 and www.clinicaltrialsregister.eu as EudraCT 2017-004012-19.

Rilzabrutinib, an Oral BTK Inhibitor, in Immune Thrombocytopenia

BACKGROUND

Rilzabrutinib, an oral, reversible covalent inhibitor of Bruton's tyrosine kinase, may increase platelet counts in patients with immune thrombocytopenia by means of dual mechanisms of action: decreased macrophage (Fcγ receptor)-mediated platelet destruction and reduced production of pathogenic autoantibodies.

METHODS

In an international, adaptive, open-label, dose-finding, phase 1-2 clinical trial, we evaluated rilzabrutinib therapy in previously treated patients with immune thrombocytopenia. We used intrapatient dose escalation of oral rilzabrutinib over a period of 24 weeks; the lowest starting dose was 200 mg once daily, with higher starting doses of 400 mg once daily, 300 mg twice daily, and 400 mg twice daily. The primary end points were safety and platelet response (defined as at least two consecutive platelet counts of ≥50×10³ per cubic millimeter and an increase from baseline of ≥20×10³ per cubic millimeter without the use of rescue medication).

RESULTS

Sixty patients were enrolled. At baseline, the median platelet count was 15×10³ per cubic millimeter, the median duration of disease was 6.3 years, and patients had received a median of four different immune thrombocytopenia therapies previously. All the treatment-related adverse events were of grade 1 or 2 and transient. There were no treatment-related bleeding or thrombotic events of grade 2 or higher. At a median of 167.5 days (range, 4 to 293) of treatment, 24 of 60 patients (40%) overall and 18 of the 45 patients (40%) who had started rilzabrutinib treatment at the highest dose met the primary end point of platelet response. The median time to the first platelet count of at least 50×10³ per cubic millimeter was 11.5 days. Among patients with a primary platelet response, the mean percentage of weeks with a platelet count of at least 50×10³ per cubic millimeter was 65%.

CONCLUSIONS

Rilzabrutinib was active and associated with only low-level toxic effects at all dose levels. The dose of 400 mg twice daily was identified as the dose for further testing. Overall, rilzabrutinib showed a rapid and durable clinical activity that improved with length of treatment. (Funded by Sanofi; ClinicalTrials.gov number, NCT03395210; EudraCT number, 2017-004012-19.).

Mitochondrial Respiration of Platelets: Comparison of Isolation Methods

Multiple non-aggregatory functions of human platelets (PLT) are widely acknowledged, yet their functional examination is limited mainly due to a lack of standardized isolation and analytic methods. Platelet apheresis (PA) is an established clinical method for PLT isolation aiming at the treatment of bleeding diathesis in severe thrombocytopenia. On the other hand, density gradient centrifugation (DC) is an isolation method applied in research for the analysis of the mitochondrial metabolic profile of oxidative phosphorylation (OXPHOS) in PLT obtained from small samples of human blood. We studied PLT obtained from 29 healthy donors by high-resolution respirometry for comparison of PA and DC isolates. ROUTINE respiration and electron transfer capacity of living PLT isolated by PA were significantly higher than in the DC group, whereas plasma membrane permeabilization resulted in a 57% decrease of succinate oxidation in PA compared to DC. These differences were eliminated after washing the PA platelets with phosphate buffer containing 10 mmol·L⁻¹ ethylene glycol-bis (2-aminoethyl ether)-N,N,N′,N′-tetra-acetic acid, suggesting that several components, particularly Ca²⁺ and fuel substrates, were carried over into the respiratory assay from the serum in PA. A simple washing step was sufficient to enable functional mitochondrial analysis in subsamples obtained from PA. The combination of the standard clinical PA isolation procedure with PLT quality control and routine mitochondrial OXPHOS diagnostics meets an acute clinical demand in biomedical research of patients suffering from thrombocytopenia and metabolic diseases.

Prediction of long-term prognosis of age-related macular degeneration treated by hemorheologic therapy using baseline laboratory indicators - Experimental-clinical model

BACKGROUND + OBJECTIVE:Age-related macular degeneration (AMD) is the most common cause of practical blindness in people over 60 years of age in industrialised countries. We formulated a hypothesis that a group of initial laboratory parameters would be suitable for prediction of prognosis of AMD, allowing for individual modifications in treatment intensity.

PATIENTS AND METHODS

66 patients with dry form of AMD were treated using rheohaemapheresis with an individual follow-up period of more than 5 years. The patients' initial laboratory data was split in two subgroups based on treatment success and analysed using discriminant analysis (analysis of the linear and quadratic models using the automated and interactive step-wise approach) by means of the Systat 13 software.

RESULTS

Prediction of prognosis based on the initial laboratory parameters was correct in 79% of unsuccessfully treated patients, allowing for early detection of high-risk patients. With the use of a quadratic model, the prediction was correct in 100% of unsuccessfully treated patients and in 75% of successfully treated patients.

CONCLUSION

Implementation of discriminant analysis is a promising method for prediction of prognosis, especially when the patient is at risk of AMD progression, which allows for early and more intensive monitoring and treatment.

Heparin-induced thrombocytopenia treated with fondaparinux: single center experience

BACKGROUND

Heparin-induced thrombocytopenia (HIT) is the most frequent drug-induced, immune-mediated thrombocytopenia. It is associated with significant morbidity and mortality. Anticoagulation with heparin must be stopped immediately and replaced by some suggested alternative - lepirudin, danaparoid or argatroban. Fondaparinux has been also successfully used in HIT.

METHODS

We present a cohort of 10 patients diagnosed with HIT and treated in a university hospital in a period of four years. Diagnosis was based on Keeling´s scoring system, screening immunologic test for HIT (STic EXPERT® HIT) and sandwich ELISA (detection of IgG/heparin-PF4 antibodies). While other alternative anticoagulants are not readily available in our hospital, we used fondaparinux in all cases.

RESULTS

From 2014 to 2018, eight males and two females (mean age 67 years, range 46-86 years) were diagnosed with HIT in our hospital. This complication developed in 9 cases after low-molecular-weight heparin and in one after heparin flushes in hemodialysis. A drop-in platelet count developed in all patients, thrombotic complications in 7 and skin necrosis in 2 cases. Fondaparinux was used in all patients, including two cases with severe renal impairment, the dose was chosen individually. We observed complete platelet recovery in all cases. One patient died because of advanced malignancy, others did not have any complication. In 6 cases we switched to oral anticoagulation after platelet recovery.

CONCLUSIONS

In our group of 10 HIT patients fondaparinux was shown to be both safe and effective, even in those with severe renal impairment. Additional studies are warranted to confirm this observation.

Analysis of Risk Factors of Stroke and Venous Thromboembolism in Females With Oral Contraceptives Use

Thrombotic diathesis has been a well-known complication of oral contraceptive use for more than 50 years. This is true not only for venous thrombosis but also for an arterial one. The etiology is usually multifactorial and depends on several additional risk factors. We analyzed the prevalence of inherited and acquired thrombophilia in a cohort of 770 females who had a thrombotic event in association with oral contraceptive use (700 women with venous thromboembolism [VTE], 70 with stroke). Moreover, we tried to identify additional risk factors. Inherited thrombophilia was found in 44.5% with higher frequency in the cohort with VTE (42%) than in females with stroke (24%). The most frequent finding was factor V Leiden. Cigarette smoking was significantly more frequent in the group with stroke (50% vs 25%). The prevalence of cigarette smoking in the group with VTE did not exceed the frequency in general population. Women on oral contraceptive pills have higher risk of venous as well as arterial thrombosis. The risk of venous thrombosis is increased in females with inherited thrombophilia, whereas those with some additional acquired risk factors (especially smoking) may be predisposed to arterial thrombosis. However, the absolute risk of thrombosis in healthy women is low, far less than the risk of unintended pregnancy. Moreover, the risk may be reduced by keeping some rules before the prescription of the pills, healthy life style, and a proper choice of contraception.

Rheopheresis in treatment of idiopathic sensorineural sudden hearing loss

Backround

Only few therapeutic options exist for patients with refractory sudden idiopathic sensorineural hearing loss (SISHL). Little is known about the efficacy of second-line therapies. Rheopheresis seems to be an effective therapeutic possibility.

Methods

Between 2012 and 2015, 106 patients with SISHL were enrolled in the study, of whom 52 were refractory to initial treatment. As salvage therapy, these patients were offered either 3 sessions of rheopheresis (33 pts) or intratympanic steroid treatment through MicroWick application (19 pts). Pure tone audiometry was performed at diagnosis, at the 1st month and the 1st year during the follow-up.

Results

Patients in the rheopheretic arm had higher hearing loss than in the MicroWick arm (81% vs. 52%, p = 0.04). In spite of this, there was a significant improvement for patients in the rheopheretic arm (27% of hearing loss reduction, p < 0.001) after the 1st month and this remained unchanged during the 1st year, while no improvement was seen in the MicroWick arm (0% of hearing loss reduction, p = 0.424). We found no predictive factor for steroid-failure in first-line therapy. Older age (p = 0.003), presence of vertigo (p = 0.006) and more profound initial hearing loss (p < 0.001) were identified as negative prognostic markers.

Conclusion

Rheopheresis can be used as a potentially effective and safe salvage therapy for patients with cortico-refractory SISHL.

Bedside assessment of amniotic fluid interleukin-6 in preterm prelabor rupture of membranes

OBJECTIVE

The objective of the study was to determine the diagnostic indices and predictive values by bedside assessment of amniotic fluid interleukin-6 (IL-6) concentration in the identification of microbial invasion of the amniotic cavity (MIAC) and/or histological chorioamnionitis (HCA) in patients with preterm prelabor rupture of membranes.

STUDY DESIGN

One hundred twenty-four women with singleton pregnancies were included in this study. The amniotic fluid was sampled by transabdominal amniocentesis at the time of admission. IL-6 concentrations were assessed with an immunoassay.

RESULTS

The presence of MIAC, HCA, or the coexistence of both was associated with higher amniotic fluid concentrations of IL-6 in both a crude and adjusted analysis. The amniotic fluid concentration of IL-6 of 1000 pg/mL was determined to be the best cutoff value for the prediction of MIAC (sensitivity of 50%, specificity of 95%, positive predictive value of 82%, negative predictive value of 81%, and likelihood ratio of 8.4) or both MIAC and HCA (sensitivity of 60%, specificity of 94%, positive predictive value of 75%, negative predictive value of 88%, and likelihood ratio of 9.4).

CONCLUSION

The bedside assessment of amniotic fluid IL-6 seems to be an easy, rapid, and inexpensive method for the prediction of MIAC or both MIAC and HCA in pregnancies complicated by preterm prelabor rupture of membranes.

Oligohydramnios in women with preterm prelabor rupture of membranes and adverse pregnancy and neonatal outcomes

OBJECTIVE

To determine the association between the presence of oligohydramnios, determined as an amniotic fluid index ≤ 5 cm and the intra-amniotic inflammatory response, fetal inflammatory response and neonatal outcomes in actively managed preterm prelabor rupture of membranes (PPROM).

METHODS

Women with singleton pregnancies complicated by PPROM at a gestational age of between 24+0 and 36+6 weeks were included in the study. Ultrasound assessments of the amniotic fluid index and evaluation of the amniotic fluid interleukin (IL)-6 levels were performed at admission. The umbilical cord blood IL-6 levels were evaluated after delivery.

RESULTS

In total, 74 women were included. The women with oligohydramnios did not have different amniotic fluid IL-6 levels [with oligohydramnios: median 342 pg/mL, interquartile range (IQR) 110-1809 vs. without oligohydramnios: median 256 pg/mL, IQR 122-748; p = 0.71] or umbilical cord blood IL-6 levels (with oligohydramnios: median 8.2 pg/mL, IQR 3.8-146.9 vs. without oligohydramnios: median 5.9 pg/mL, IQR 2.1-27.9; p = 0.14) than those without oligohydramnios. No association between oligohydramnios and neonatal morbidity was found. A correlation between the amniotic fluid index and the interval from rupture of membranes to amniocentesis was observed (rho = -0.34; p = 0.003).

CONCLUSION

The presence of oligohydramnios is not associated with an adverse outcome in actively managed PPROM in singleton pregnancies in the absence of other complications.

Prelabor rupture of membranes between 34 and 37 weeks: the intraamniotic inflammatory response and neonatal outcomes

OBJECTIVE

We sought to determine the influence of microbial invasion of the amniotic cavity (MIAC) and acute histologic chorioamnionitis (HCA) on the intensity of the intraamniotic inflammatory response and neonatal morbidity in preterm prelabor rupture of membranes (PPROM) between 34-37 weeks.

STUDY DESIGN

This study included 99 women with singleton pregnancies complicated by PPROM between the gestational ages of 34-37 weeks. Amniocenteses were performed at the time of admission, and MIAC and amniotic fluid interleukin-6 concentrations were determined. After delivery, the placenta was evaluated for the presence of HCA.

RESULTS

Women with both MIAC and HCA had the highest intraamniotic inflammatory response, which was mediated by interleukin-6 concentrations (both MIAC and HCA: median 2164.0 pg/mL; HCA alone: median 654.8 pg/mL; MIAC alone: median 784.1 pg/mL; neither MIAC nor HCA: median 383.0 pg/mL; P < .0001) and the highest incidence of newborns with early-onset sepsis (P = .02).

CONCLUSION

Both MIAC and HCA affect the intensity of the intraamniotic inflammatory response and the incidence of early-onset sepsis following PPROM between 34-37 weeks. The intensity of the intraamniotic inflammatory response should be considered in the clinical management of PPROM between 34-37 weeks.

The decrease of mean platelet volume after extracorporeal LDL-cholesterol elimination

OBJECTIVE

Mean platelet volume is arousing increasing interest as a new independent cardiovascular risk factor. Large platelets are likely to be more reactive. If mean platelet volume would drop after LDL-lowering therapy, decreased MPV could be one of the markers of successful therapy. Therefore, we investigated mean platelet volume after extracorporeal LDL-cholesterol elimination.

METHODS

Mean platelet volume was investigated in patients with severe familial hypercholesterolemia long-term treated (3-12 years) by LDL-apheresis (immunoapheresis) or cascade filtration. Plasma was obtained by centrifugation. Adsorbers Lipopak 400 were used for immunoapheresis and filters Evaflux 4A were used for cascade filtration. 95 pair samples were measured (before and after the procedures) in a group of 12 patients--each patient 8 times in 4 years.

RESULTS

Mean platelet volume before the procedures was 10.891 fl, CI 10.25-11.53. Mean platelet volume after the procedures decreased--10.478 fl, CI 09.84-11.11. The difference is statistically significant (p = 0.036). Mean platelet volume did not correlate with age, sex, platelet count, duration of therapy. At the same time, we used rheohemapheresis in the therapy of 40 patients with age-related macular degeneration. But mean platelet volume was not changed.

CONCLUSION

Mean platelet volume is easily available and is often disregarded, and sometimes may suggest the need for a careful assessment in patients with familial hypercholesterolemia. Mean platelet volume could be one of the markers of therapeutic efficacy in patients with familial hypercholesterolemia treated by extracorporeal LDL-cholesterol elimination that is simple and inexpensive.

Ultrasound measurement of the transverse diameter of the fetal thymus in pregnancies complicated by the preterm prelabor rupture of membranes

PURPOSE

To determine whether the measurement of the transverse diameter of the fetal thymus is of value in the identification of either histologic chorioamnionitis or funisitis in pregnancies complicated by preterm prelabor rupture of membranes (PPROM).

METHODS

The transverse diameter of the fetal thymus was measured in 216 fetuses from PPROM pregnancies. A small thymus was defined as a transverse thymic diameter below the fifth percentile according to a previously published nomogram. The placenta, the fetal membranes, and the umbilical cord were assessed for the presence of inflammation.

RESULTS

A small thymus was identified in 69% (150/216) of fetuses. A small thymus was present in 80% (106/133) and 88% (36/41) of women with histologic chorioamnionitis or funisitis, respectively. The presence of a small thymus had a sensitivity of 79%, specificity of 47%, positive predictive value of 71%, negative predictive value of 59% for the identification of chorioamnionitis (p < 0.0001; odds ratio 3.5) and a sensitivity of 88%, specificity of 35%, positive predictive value of 24%, and negative predictive value of 92% in the identification of funisitis (p = 0.004; odds ratio 4.4).

CONCLUSIONS

The sonographic finding of a small thymus is a sensitive indicator of histologic chorioamnionitis or funisitis; low specificity excludes it as a possible clinical implication in the management of PPROM pregnancies.

Pulsation of the fetal splenic vein--a potential ultrasound marker of histological chorioamnionitis and funisitis in women with preterm prelabor rupture of membranes

The fetal spleen is involved in the response to intrauterine infection and inflammation. The flow pattern of its vein is not pulsatile in normal conditions. The aim of the study was to determine whether the presence of histological chorioamnionitis and funisitis is associated with a continuous or pulsatile flow pattern in the fetal splenic vein. We performed a prospective study including 79 women with preterm prelabor rupture of membranes. We found a relation between pulsation in the splenic vein and histological chorioamnionitis (likelihood ratio 13.2), as well as funisitis (likelihood ratio 5.7). Ultrasound evaluation of the splenic vein could be a non-invasive tool for the prediction of these inflammatory complications.

Long-term outcomes of patients with cerebral vein thrombosis: a multicenter study

BACKGROUND

Little information is available on the long-term clinical outcome of cerebral vein thrombosis (CVT).

OBJECTIVES AND METHODS

In an international, retrospective cohort study, we assessed the long-term rates of mortality, residual disability and recurrent venous thromboembolism (VTE) in a cohort of patients with a first CVT episode.

RESULTS

Seven hundred and six patients (73.7% females) with CVT were included. Patients were followed for a total of 3171 patient-years. Median follow-up was 40 months (range 6, 297 months). At the end of follow-up, 20 patients had died (2.8%). The outcome was generally good: 89.1% of patients had a complete recovery (modified Rankin Score [mRS] 0-1) and 3.8% had a partial recovery and were independent (mRS 2). Eighty-four per cent of patients were treated with oral anticoagulants and the mean treatment duration was 12 months. CVT recurred in 31 patients (4.4%), and 46 patients (6.5%) had a VTE in a different site, for an overall incidence of recurrence of 23.6 events per 1000 patient-years (95% confidence Interval [CI] 17.8, 28.7) and of 35.1 events/1000 patient-years (95% CI, 27.7, 44.4) after anticoagulant therapy withdrawal. A previous VTE was the only significant predictor of recurrence at multivariate analysis (hazard ratio [HR] 2.70; 95% CI 1.25, 5.83).

CONCLUSIONS

The long-term risk of mortality and recurrent VTE appears to be low in patients who survived the acute phase of CVT. A previous VTE history independently predicts recurrent events.