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Methods: We searched Medline, Scopus, Clinicaltrials.org, The Cochrane Central Register of Controlled Trials and Google Scholar search engines.
Results: Six studies were included that involved 880 women. Double cerclage was significantly superior to single cerclage in reducing preterm births <34?weeks (734 cases, OR 0.59, 95% CI 0.40, 0.86) and preterm births <28?weeks (645 cases, OR 0.43, 95% CI 0.26–0.73). It also significantly increased the gestational age (380 cases, MD 2.63, 95% CI 0.87, 4.39). However, as a technique, it failed to improve the rates of preterm births <37?weeks (740 cases, OR 0.98, 95% CI 0.72, 1.34) the incidence of chorioamnionitis (740 cases, OR 0.83, 95% CI 0.51, 1.36) and the occurrence of preterm premature rupture of the membranes (796 cases, OR 1.32, 95% CI 0.95, 1.82).
Conclusions: It seems that double cerclage effectively increases the gestational age at delivery and decreases the rates of extremely premature births. However, as a procedure, it does not reduce the incidence of antenatal morbidity or the neonatal death rates. Further research is needed in the field as our meta-analysis is limited by the small number of enrolled studies. 相似文献
Purpose
With the introduction of biosimilars of anticancer monoclonal antibodies (mAbs) in oncology, physicians are potentially confronted with the question whether it is clinically adequate to switch patients who are clinically stable on treatment with the reference product to a newly available biosimilar (or vice versa/from 1 biosimilar to another). For a proper impact assessment of switching, robust, product-specific, and clinically relevant evidence should be required, ideally including data from appropriately designed switching studies. In this article, we assess the current body of switching data available for approved or proposed biosimilars of anticancer mAbs.Methods
PubMed was systematically searched and ClinicalTrials.gov and abstract databases of selected congresses were hand-searched to identify all switching studies including biosimilars of anticancer mAbs.Findings
We identified 8 switching studies with biosimilars of rituximab (CT-P10, GP2013, PF-05280586, and BCD-020) and trastuzumab (ABP 980). Two were performed in oncology indications and the other 6 in rheumatoid arthritis (RA). Key elements of a well-designed switching study, such as randomization and blinding, were contained in several of the studies, but significant limitations were also present. The most frequent limitations were low statistical power because of small patient numbers, lack of an appropriate control arm, short follow-up, chosen outcome measures, and (for studies performed in RA) the concern whether switching data can be extrapolated to oncology indications. Accordingly, the data from these studies need to be interpreted with caution. Of note, all identified studies included a single switch only, whereas multiple switches may occur in the real-world setting. The scientific need to evaluate the impact of repeated switching has been recognized by the US Food and Drug Administration, who incorporated such a requirement in its draft guidance on interchangeability.Implications
From the scarce data available, the consequences of switching between reference product mAbs and their biosimilar(s) in the oncology setting are as yet unknown. Additional clinical evidence from well-designed switching studies is needed to guide switching decisions. 相似文献Patients with patent foramen ovale (PFO) and cryptogenic ischemic stroke (CS) are at risk for stroke recurrence. The optimal antithrombotic strategy in patients who undergo medical management is still debated.
MethodsWe systematically searched the literature for studies that reported on cerebrovascular event recurrences and/or death in patients with PFO treated with oral anticoagulation (OAC) or antiplatelet therapy (APT) for secondary prevention of CS. The efficacy endpoints were stroke recurrence and the composite of stroke, transient ischemic attack or all-cause death. Major bleedings represented the safety endpoint.
ResultsA total of 16 studies with 3953 patients (OAC?=?1527, APT?=?2426) were included. Weighted mean follow-up was 2.9 years. OAC was associated with a significant reduction in the risk of stroke compared with APT (RR 0.65; 95% CI 0.44–0.95; ARR 2%, NNT 49), while no difference was found regarding the composite outcome (RR 0.78; 95% CI 0.57–1.07) and the safety outcome (RR 1.57; 95% CI 0.85–2.90; p?=?0.15).
ConclusionsOAC was more effective than APT in reducing the risk of stroke recurrence in patients with PFO and CS, without a significant increase in the risk of major bleedings. Our findings support the need for further randomized data focused on the comparison of antithrombotic strategies in this setting.
相似文献