Validating the early phototherapy prediction tool across cohorts.

Background: Hyperbilirubinemia of the newborn infant is a common disease worldwide. However, recognized early and treated appropriately, it typically remains innocuous. We recently developed an early phototherapy prediction tool (EPPT) by means of machine learning (ML) utilizing just one bilirubin measurement and few clinical variables. The aim of this study is to test applicability and performance of the EPPT on a new patient cohort from a different population. Materials and methods: This work is a retrospective study of prospectively recorded neonatal data from infants born in 2018 in an academic hospital, Regensburg, Germany, meeting the following inclusion criteria: born with 34 completed weeks of gestation or more, at least two total serum bilirubin (TSB) measurement prior to phototherapy. First, the original EPPT-an ensemble of a logistic regression and a random forest-was used in its freely accessible version and evaluated in terms of the area under the receiver operating characteristic curve (AUROC). Second, a new version of the EPPT model was re-trained on the data from the new cohort. Third, the predictive performance, variable importance, sensitivity and specificity were analyzed and compared across the original and re-trained models. Results: In total, 1,109 neonates were included with a median (IQR) gestational age of 38.4 (36.6-39.9) and a total of 3,940 bilirubin measurements prior to any phototherapy treatment, which was required in 154 neonates (13.9%). For the phototherapy treatment prediction, the original EPPT achieved a predictive performance of 84.6% AUROC on the new cohort. After re-training the model on a subset of the new dataset, 88.8% AUROC was achieved as evaluated by cross validation. The same five variables as for the original model were found to be most important for the prediction on the new cohort, namely gestational age at birth, birth weight, bilirubin to weight ratio, hours since birth, bilirubin value. Discussion: The individual risk for treatment requirement in neonatal hyperbilirubinemia is robustly predictable in different patient cohorts with a previously developed ML tool (EPPT) demanding just one TSB value and only four clinical parameters. Further prospective validation studies are needed to develop an effective and safe clinical decision support system.

Leveraging Predictive Pharmacometrics-Based Algorithms to Enhance Perinatal Care-Application to Neonatal Jaundice.

The field of medicine is undergoing a fundamental change, transforming towards a modern data-driven patient-oriented approach. This paradigm shift also affects perinatal medicine as predictive algorithms and artificial intelligence are applied to enhance and individualize maternal, neonatal and perinatal care. Here, we introduce a pharmacometrics-based mathematical-statistical computer program (PMX-based algorithm) focusing on hyperbilirubinemia, a medical condition affecting half of all newborns. Independent datasets from two different centers consisting of total serum bilirubin measurements were utilized for model development (342 neonates, 1,478 bilirubin measurements) and validation (1,101 neonates, 3,081 bilirubin measurements), respectively. The mathematical-statistical structure of the PMX-based algorithm is a differential equation in the context of non-linear mixed effects modeling, together with Empirical Bayesian Estimation to predict bilirubin kinetics for a new patient. Several clinically relevant prediction scenarios were validated, i.e., prediction up to 24 h based on one bilirubin measurement, and prediction up to 48 h based on two bilirubin measurements. The PMX-based algorithm can be applied in two different clinical scenarios. First, bilirubin kinetics can be predicted up to 24 h based on one single bilirubin measurement with a median relative (absolute) prediction difference of 8.5% (median absolute prediction difference 17.4 µmol/l), and sensitivity and specificity of 95.7 and 96.3%, respectively. Second, bilirubin kinetics can be predicted up to 48 h based on two bilirubin measurements with a median relative (absolute) prediction difference of 9.2% (median absolute prediction difference 21.5 µmol/l), and sensitivity and specificity of 93.0 and 92.1%, respectively. In contrast to currently available nomogram-based static bilirubin stratification, the PMX-based algorithm presented here is a dynamic approach predicting individual bilirubin kinetics up to 48 h, an intelligent, predictive algorithm that can be incorporated in a clinical decision support tool. Such clinical decision support tools have the potential to benefit perinatal medicine facilitating personalized care of mothers and their born and unborn infants.

Efficacy and Safety of a Fixed Combination of Cinnarizine 20 mg and Dimenhydrinate 40 mg vs Betahistine Dihydrochloride 16 mg in Patients with Peripheral Vestibular Vertigo: A Prospective, Multinational, Multicenter, Double-Blind, Randomized, Non-inferiority Clinical Trial.

BACKGROUND AND OBJECTIVE: Vertigo derived from peripheral vestibular disorders is quite frequently encountered in daily clinical practice and can be a severely disabling symptom associated with substantial impairment of health-related quality of life for the affected patients. Betahistine, a structural analogue of histamine and presumably the most widely prescribed anti-vertigo drug worldwide, has previously been shown to be an effective and safe treatment for these patients. The objective of the present study was to evaluate whether the fixed combination of cinnarizine and dimenhydrinate (Arlevert®) is non-inferior and thus a potentially useful alternative to betahistine dihydrochloride in the treatment of patients suffering from peripheral vestibular vertigo. METHODS: In this prospective, multicenter, double-blind, randomized, non-inferiority clinical trial, outpatients from 8 ENT clinics in Austria, Bulgaria, the Czech Republic and Russia were randomly assigned to receive three times daily one tablet of either the fixed combination cinnarizine 20 mg/dimenhydrinate 40 mg or betahistine dihydrochloride 16 mg for 4 weeks. Primary endpoint was the reduction of the mean vertigo score (MVS), a validated 12-item composite score defined as the mean of 6 vertigo symptoms (dystasia and walking unsteadiness, staggering, rotary sensation, tendency to fall, lift sensation, blackout) and 6 trigger factors for vertigo (change of position, bowing, getting up, driving by car/train, head movements, eye movement), after 4 weeks of therapy, as judged by the patient on a 5-point visual analogue scale (VAS). The non-inferiority margin was set to 0.3. Secondary outcomes included the patient's and investigator's judgment of global efficacy, the patient's rating of impairment of daily activities, and safety/tolerability of the treatments. RESULTS: Three hundred and six patients (mean age 53.5 years, approximately 60% female) were enrolled and randomized to the fixed combination cinnarizine/dimenhydrinate (n = 152) or betahistine (n = 154) groups; 297 patients completed the study and 294 (146 and 148, respectively) were valid for the per-protocol analysis, which was used for the non-inferiority analysis. Treatment with cinnarizine/dimenhydrinate led to a stronger reduction of the MVS [least squares mean (LSM)] after 4-week therapy (primary endpoint) in comparison to betahistine (0.395 vs 0.488; difference: - 0.093, 95% CI - 0.180; - 0.007, p = 0.035); since the upper limit of the two-sided 95% confidence interval was not only below the non-inferiority margin of 0.3, but also entirely below 0, superiority of the fixed combination could be demonstrated. The combination preparation was also more effective after 1 week of therapy and received more favorable patient's ratings on overall efficacy and impairment of daily activities. Both treatments were very well tolerated. Only 12 patients (3.92%) reported 13 non-serious adverse events; 2 cinnarizine/dimenhydrinate-treated patients discontinued the study prematurely due to adverse events as compared to 5 betahistine-treated patients. CONCLUSION: The fixed combination of cinnarizine 20 mg and dimenhydrinate 40 mg was found to be not only non-inferior, but superior to betahistine 16 mg in the improvement of peripheral vestibular vertigo. Furthermore, taking into account a good and slightly favorable safety profile, the present study provides evidence that the fixed-combination preparation is a potent and even superior alternative to betahistine in the treatment of vertigo related to peripheral vestibular disorders. STUDY REGISTRATION: EudraCT No. 2011-004025-27.

Ranolazine in the treatment of atrial fibrillation: Results of the dose-ranging RAFFAELLO (Ranolazine in Atrial Fibrillation Following An ELectricaL CardiOversion) study.

BACKGROUND: Currently available antiarrhythmic agents for the treatment of atrial fibrillation (AF) have important limitations, leaving an unmet need for safe and effective therapy. Ranolazine is an approved antianginal agent with a favorable safety profile and electrophysiologic properties suggesting a potential role in the treatment of AF. OBJECTIVE: The purpose of this study was to assess the safety and efficacy of ranolazine in the prevention of AF recurrence after successful electrical cardioversion and to ascertain the most appropriate dose of this agent. METHODS: This prospective, multicenter, randomized, double-blind, placebo-control parallel group phase II dose-ranging trial randomized patients with persistent AF (7 days to 6 months) 2 hours after successful electrical cardioversion to placebo, or ranolazine 375 mg, 500 mg, or 750 mg bid. Patients were monitored daily by transtelephonic ECG. The primary end-point was the time to first AF recurrence. RESULTS: Of 241 patients randomized, 238 took at least 1 drug dose. Ranolazine proved to be safe and tolerable. No dose of the drug significantly prolonged time to AF recurrence. AF recurred in 56.4%, 56.9%, 41.7%, and 39.7% of patients in the placebo, ranolazine 375 mg, ranolazine 500 mg, and ranolazine 750 mg groups, respectively. The reduction in overall AF recurrence in the combined 500-mg and 750-mg groups was of borderline significance compared to the placebo group (P = .053) and significant compared to 375-mg group (P = .035). CONCLUSION: No dose of ranolazine significantly prolonged time to AF recurrence. However, the 500-mg and 750 mg-groups combined reduced AF recurrences, suggesting a possible role for this agent in the treatment of AF.

Fine-tuning of regulatory T cell function: the role of calcium signals and naive regulatory T cells for regulatory T cell deficiency in multiple sclerosis.

The suppressor function of regulatory T cells (Tregs) is impaired in multiple sclerosis (MS), but the mechanisms underlying this deficiency are not fully understood. As Tregs counteract the sustained elevation of intracellular calcium, which is indispensable for full activation of conventional T cells (Tcons), we hypothesized that interference with this pathway might prompt MS-related Treg dysfunction. Using single-cell live imaging, we observed that Tregs rapidly reduce Ca(2+) influx and downstream signals in Tcons upon cell contact, yet differ in their potency to efficiently suppress several target cells at the same time. Strikingly, individual Tregs harboring a CD4(+)CD25(+)FOXP3(+)CD45RA(+) naive phenotype suppressed significantly more adjacent Tcons than did CD4(+)CD25(+)FOXP3(+)CD45RA(-) memory Tregs. Some constituents even completely failed to dampen Tcon Ca(2+) influx and were contained exclusively in the memory subset. In accordance with their more powerful suppressive performance, the Ca(2+) signature was considerably enhanced in naive Tregs in response to TCR triggering, compared with the memory counterparts. MS Tregs displayed a significantly diminished suppression of mean Ca(2+) influx in the sum of individual Tcons recorded. This reduced inhibitory activity was closely linked to decreased numbers of individual Tcons becoming suppressed by adjacent Tregs and, in turn, correlated with a marked reduction of naive subtypes and concomitant expansion of nonsuppressive memory phenotypes. We conclude that the superior achievement of naive Tregs is pivotal in maintaining Treg efficiency. As a consequence, MS Tregs become defective because they lack naive subtypes and are disproportionately enriched in memory cells that have lost their inherent downregulatory activity.

Efficacy and safety of olmesartan medoxomil 40 mg/hydrochlorothiazide 12.5 mg combination therapy versus olmesartan medoxomil 40 mg monotherapy in patients with moderate to severe hypertension: a randomized, double-blind, parallel-group, multicentre, multinational, phase III study.

BACKGROUND: Current hypertension guidelines recommend using two antihypertensive agents when blood pressure (BP) control is not achieved with one single agent. OBJECTIVE: This study was designed to assess the antihypertensive benefit of the olmesartan medoxomil 40 mg/hydrochlorothiazide (HCTZ) 12.5 mg combination versus olmesartan medoxomil 40 mg monotherapy in patients with moderate to severe hypertension. METHODS: This was a randomized, double-blind, parallel-group, up-titration, multicentre, multinational, phase III study. Following a 2-week single-blind placebo run-in phase, 846 hypertensive patients with mean seated systolic BP (SeSBP) of 160-200 mmHg and mean seated diastolic BP (SeDBP) of 100-120 mmHg were randomized (1 : 2 ratio) to receive double-blind treatment with olmesartan medoxomil 40 mg or olmesartan medoxomil 40 mg/HCTZ 12.5 mg for 8 weeks (phase A). At week 8, patients not reaching BP goal (<140/90 mmHg; <130/80 mmHg in patients with diabetes mellitus) were up-titrated from olmesartan medoxomil 40 mg to olmesartan medoxomil 40 mg/HCTZ 12.5 mg or from olmesartan medoxomil 40 mg/HCTZ 12.5 mg to olmesartan medoxomil 40 mg/HCTZ 25 mg for an additional 8 weeks (phase B). Patients on goal continued their initial treatment. The primary efficacy parameter was the change in mean SeDBP during phase A. RESULTS: Olmesartan medoxomil 40 mg/HCTZ 12.5 mg reduced mean SeDBP significantly more (-18.9 mmHg) than olmesartan medoxomil 40 mg (-15.8 mmHg) after 8 weeks of double-blind treatment (difference: -3.1 mmHg, p < 0.0001). Olmesartan medoxomil 40 mg/HCTZ 12.5 mg also reduced mean SeSBP significantly more than olmesartan medoxomil 40 mg (-5.4 mmHg, p < 0.0001). As a result, BP goal rates at week 8 were significantly higher with olmesartan medoxomil 40 mg/HCTZ 12.5 mg than with olmesartan medoxomil 40 mg (58.5% vs 44.3%; odds ratio 1.88; 95% CI 1.32, 2.54). During phase B, mean BP reductions were greater in patients up-titrated from olmesartan medoxomil 40 mg to olmesartan medoxomil 40 mg/HCTZ 12.5 mg than in those continuing on olmesartan medoxomil 40 mg (SeDBP: -9.3 mmHg vs -0.5 mmHg; SeSBP: -12.4 mmHg vs -0.5 mmHg). Similarly, mean BP reductions were greater in patients up-titrated from olmesartan medoxomil 40 mg/HCTZ 12.5 mg to olmesartan medoxomil 40 mg/HCTZ 25 mg than in those continuing on olmesartan medoxomil 40 mg/HCTZ 12.5 mg (SeDBP: -8.0 mmHg vs -0.3 mmHg; SeSBP: -12.1 mmHg vs -0.4 mmHg). In patients not on goal at week 8, addition of HCTZ 12.5 mg to olmesartan medoxomil 40 mg or up-titration from olmesartan medoxomil 40 mg/HCTZ 12.5 mg to olmesartan medoxomil 40 mg/HCTZ 25 mg brought additional patients to goal at week 16 (38.8% vs 36.9%). All treatments were well tolerated. CONCLUSION: The olmesartan medoxomil 40 mg/HCTZ 12.5 mg combination is superior to olmesartan medoxomil 40 mg monotherapy in reducing SeDBP and SeSBP and increasing BP goal rates after 8 weeks. Patients not on goal at week 8 with olmesartan medoxomil 40 mg or olmesartan medoxomil 40 mg/HCTZ 12.5 mg benefited from adding HCTZ 12.5 mg or up-titrating to olmesartan medoxomil 40 mg/HCTZ 25 mg, respectively, confirming that up-titration is a clinically meaningful way to improve BP control. [ TRIAL REGISTRATION NUMBER: NCT00441350 (ClinicalTrials.gov Identifier)].