Predictive value of quantitative fetal fibronectin for spontaneous preterm birth in asymptomatic pregnancies: a systematic literature review and meta-analysis.

OBJECTIVE: Tests capable of accurate prediction of spontaneous preterm birth (sPTB) are crucial to inform clinical decisions to prevent neonatal deaths and reduce the risk of morbidity in surviving infants. A systematic literature review and meta-analysis were performed to assess the utility of the quantitative fetal fibronectin (fFN) test to predict sPTB at different test concentration thresholds. METHODS: Literature searches were conducted in MEDLINE, Embase, and the Cochrane Library in May 2022. Observational studies and clinical trials investigating the clinical utility of the quantitative fFN test in asymptomatic pregnancies prior to 37 weeks of gestation were eligible for inclusion. Meta-analysis quantified the risk of sPTB prior to four gestational age milestones (<28, <30, <34 and <37 weeks) based on quantitative fFN levels. No risk of bias assessment was performed however, clinical and methodological heterogeneity was explored to determine the feasibility of performing analyses. RESULTS: 11 studies showed a quantitative assessment of fFN can differentiate between very high and very low risks of sPTB in asymptomatic pregnancies with <10% of women with very low fFN (<10 ng/mL) versus 37-67% of women with very high fFN (>200 ng/mL) delivering before 34 weeks. A meta-analysis of two studies showed, albeit with a low number of events, the odds of sPTB prior to 28 weeks was nine times higher in women testing positive at ≥50 ng/mL, whereas the odds of sPTB was 25 times higher in women with fFN concentrations >200 ng/mL (versus <50 ng/mL reference). Similarly, pooling three studies showed the odds of sPTB prior to 37 weeks was four times higher in women who tested positive at ≥50 ng/ml whereas the odds of delivery before 37 weeks was seven times higher for women with fFN concentrations ≥200 ng/ml (versus <50 ng/mL reference). CONCLUSION: Quantitative fFN testing demonstrates increased predictive capabilities and utility of fFN testing in clinical practice, potentially preventing unnecessary intervention for women at very low risk and allowing an opportunity to optimize the management of asymptomatic patients at high risk of preterm delivery.

Epidemiological and clinical burden associated with plexiform neurofibromas in pediatric neurofibromatosis type-1 (NF-1): a systematic literature review.

PURPOSE: Patients with neurofibromatosis type-1 (NF-1) and associated plexiform neurofibromas (PNs) often have a high burden of illness owing to debilitating symptoms of these tumors and limited management options. To investigate this complex disease, a systematic literature review (SLR) was conducted on the epidemiology of pediatric NF-1 and associated PNs, the burden of illness, and outcomes of surgical resection of these tumors. METHODS: Searches of MEDLINE and Embase (from database inception to October 2019) and conference proceedings (2017-2019) were performed to identify relevant studies. The review methodology was informed by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. RESULTS: Twenty studies were identified. Evidence confirmed NF-1 is rare but that occurrence may differ geographically. Only limited data on the birth incidence of NF-1 were identified. Prevalence estimates for pediatric NF-1 varied from one per 960 individuals (aged 17 years) to one per 5681 children (aged < 16 years) across five large registry/surveillance studies (each involving > 19,000 individuals). The prevalence of associated PNs was 0-29.6%. PNs carried increased mortality risk in pediatric NF-1 in both studies that explored this potential association. Patients with PNs reported high use of analgesics. The complication rate post-surgery for PNs was around 17-19%. The recurrence rate (18-68%) was dependent on the extent of excision achieved during surgery. CONCLUSIONS: Data suggest NF-1 is a rare disease with increased morbidity and mortality in children with associated PNs. Surgical outcomes for PNs are often poor. These findings suggest significant unmet needs in patients with NF-1-associated PNs.

Enzyme-linked immunosorbent assays for monitoring TNF-alpha inhibitors and antibody levels in people with rheumatoid arthritis: a systematic review and economic evaluation.

BACKGROUND: Rheumatoid arthritis is a chronic autoimmune disease that primarily causes inflammation, pain and stiffness in the joints. People with severe disease may be treated with biological disease-modifying anti-rheumatic drugs, including tumour necrosis factor-α inhibitors, but the efficacy of these drugs is hampered by the presence of anti-drug antibodies. Monitoring the response to these treatments typically involves clinical assessment using response criteria, such as Disease Activity Score in 28 joints or European League Against Rheumatism. Enzyme-linked immunosorbent assays can also be used to measure drug and antibody levels in the blood. These tests may inform whether or not adjustments to treatment are required or help clinicians to understand the reasons for treatment non-response or a loss of response. METHODS: Systematic reviews were conducted to identify studies reporting on the clinical effectiveness and cost-effectiveness of using enzyme-linked immunosorbent assays to measure drug and anti-drug antibody levels to monitor the response to tumour necrosis factor-α inhibitors [adalimumab (Humira®; AbbVie, Inc., North Chicago, IL, USA), etanercept (Enbrel®; Pfizer, Inc., New York, NY, USA), infliximab (Remicade®, Merck Sharp & Dohme Limited, Hoddesdon, UK), certolizumab pegol (Cimzia®; UCB Pharma Limited, Slough, UK) and golimumab (Simponi®; Merck Sharp & Dohme Limited)] in people with rheumatoid arthritis who had either achieved treatment target (remission or low disease activity) or shown primary or secondary non-response to treatment. A range of bibliographic databases, including MEDLINE, EMBASE and CENTRAL (Cochrane Central Register of Controlled Trials), were searched from inception to November 2018. The risk of bias was assessed using the Cochrane ROBINS-1 (Risk Of Bias In Non-randomised Studies - of Interventions) tool for non-randomised studies, with adaptations as appropriate. Threshold and cost-utility analyses that were based on a decision tree model were conducted to estimate the economic outcomes of adding therapeutic drug monitoring to standard care. The costs and resource use were considered from the perspective of the NHS and Personal Social Services. No discounting was applied to the costs and effects owing to the short-term time horizon of 18 months that was adopted in the economic analysis. The impact on the results of variations in testing and treatment strategies was explored in numerous clinically plausible sensitivity analyses. RESULTS: Two studies were identified: (1) a non-randomised controlled trial, INGEBIO, that compared standard care with therapeutic drug monitoring using Promonitor® assays [Progenika Biopharma SA (a Grifols-Progenika company), Derio, Spain] in Spanish patients receiving adalimumab who had achieved remission or low disease activity; and (2) a historical control study. The economic analyses were informed by INGEBIO. Different outcomes from INGEBIO produced inconsistent results in both threshold and cost-utility analyses. The cost-effectiveness of therapeutic drug monitoring varied, from the intervention being dominant to the incremental cost-effectiveness ratio of £164,009 per quality-adjusted life-year gained. However, when the frequency of testing was assumed to be once per year and the cost of phlebotomy appointments was excluded, therapeutic drug monitoring dominated standard care. LIMITATIONS: There is limited relevant research evidence and much uncertainty about the clinical effectiveness and cost-effectiveness of using enzyme-linked immunosorbent assay-based testing for therapeutic drug monitoring in rheumatoid arthritis patients. INGEBIO had serious limitations in relation to the National Institute for Health and Care Excellence scope: only one-third of participants had rheumatoid arthritis, the analyses were mostly not by intention to treat and the follow-up was 18 months only. Moreover, the outcomes might not be generalisable to the NHS. CONCLUSIONS: Based on the available evidence, no firm conclusions could be made about the cost-effectiveness of therapeutic drug monitoring in England and Wales. FUTURE WORK: Further controlled trials are required to assess the impact of using enzyme-linked immunosorbent assays for monitoring the anti-tumour necrosis factors in people with rheumatoid arthritis. STUDY REGISTRATION: This study is registered as PROSPERO CRD42018105195. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 8. See the NIHR Journals Library website for further project information.

Rheumatoid arthritis is a long-term condition that causes pain, swelling and stiffness in the joints. People with severe disease may be treated with drugs called tumour necrosis factor-α inhibitors [adalimumab (Humira^®; AbbVie Inc., North Chicago, IL, USA), etanercept (Enbrel^®; Pfizer, Inc., New York, NY, USA), infliximab (Remicade^®; Merck Sharp & Dohme Limited, Hoddesdon, UK), certolizumab pegol (Cimzia^®; UCB Pharma Limited, Slough, UK) and golimumab (Simponi^®; Merck Sharp & Dohme Limited)]. Some people taking these drugs find that their disease improves, whereas others do not respond to the treatment or improve initially and then experience loss of response. One cause of lost response is that individuals develop antibodies (i.e. protective proteins) against the drug, which hamper the effect of treatment. Various tests have been developed to measure the level of drugs and antibodies against these drugs in patient's blood samples. This kind of monitoring would allow treatment to be adjusted in response to the test outcomes to optimise benefit for the patient, and help clinicians to better understand the reasons for an absence or a loss of response to treatment. The aim of this study was to find out whether or not it would be clinically effective (i.e. good for patients) and cost-effective (i.e. a good use of NHS resources) to use these tests for monitoring drug and antibody levels, as a means of assessing treatment response in rheumatoid arthritis patients who are controlled, have not responded or have lost response. Results from a systematic review showed that, because of the limited and poor-quality evidence, there was much uncertainty in the clinical effectiveness of testing. A simple mathematical model drew on evidence from one poorly reported study, which was heavily supplemented by data from other studies and expert advice. Results from the model were inconclusive and suggest that there is considerable uncertainty in the cost-effectiveness of testing. Therefore, the results presented here should be considered with caution. Further studies are needed to assess the impact of tumour necrosis factor testing in patients with rheumatoid arthritis.

Three biomarker tests to help diagnose preterm labour: a systematic review and economic evaluation.

BACKGROUND: Preterm birth may result in short- and long-term health problems for the child. Accurate diagnoses of preterm births could prevent unnecessary (or ensure appropriate) admissions into hospitals or transfers to specialist units. OBJECTIVES: The purpose of this report is to assess the test accuracy, clinical effectiveness and cost-effectiveness of the diagnostic tests PartoSure™ (Parsagen Diagnostics Inc., Boston, MA, USA), Actim® Partus (Medix Biochemica, Espoo, Finland) and the Rapid Fetal Fibronectin (fFN)® 10Q Cassette Kit (Hologic, Inc., Marlborough, MA, USA) at thresholds ≠50 ng/ml [quantitative fFN (qfFN)] for women presenting with signs and symptoms of preterm labour relative to fFN at 50 ng/ml. METHODS: Systematic reviews of the published literature were conducted for diagnostic test accuracy (DTA) studies of PartoSure, Actim Partus and qfFN for predicting preterm birth, the clinical effectiveness following treatment decisions informed by test results and economic evaluations of the tests. A model-based economic evaluation was also conducted to extrapolate long-term outcomes from the results of the diagnostic tests. The model followed the structure of the model that informed the 2015 National Institute for Health and Care Excellence guidelines on preterm labour diagnosis and treatment, but with antenatal steroids use, as opposed to tocolysis, driving health outcomes. RESULTS: Twenty studies were identified evaluating DTA against the reference standard of delivery within 7 days and seven studies were identified evaluating DTA against the reference standard of delivery within 48 hours. Two studies assessed two of the index tests within the same population. One study demonstrated that depending on the threshold used, qfFN was more or less accurate than Actim Partus, whereas the other indicated little difference between PartoSure and Actim Partus. No study assessing qfFN and PartoSure in the same population was identified. The test accuracy results from the other included studies revealed a high level of uncertainty, primarily attributable to substantial methodological, clinical and statistical heterogeneity between studies. No study compared all three tests simultaneously. No clinical effectiveness studies evaluating any of the three biomarker tests were identified. One partial economic evaluation was identified for predicting preterm birth. It assessed the number needed to treat to prevent a respiratory distress syndrome case with a 'treat-all' strategy, relative to testing with qualitative fFN. Because of the lack of data, our de novo model involved the assumption that management of pregnant women fully adhered to the results of the tests. In the base-case analysis for a woman at 30 weeks' gestation, Actim Partus had lower health-care costs and fewer quality-adjusted life-years (QALYs) than qfFN at 50 ng/ml, reducing costs at a rate of £56,030 per QALY lost compared with qfFN at 50 ng/ml. PartoSure is less costly than Actim Partus while being equally effective, but this is based on diagnostic accuracy data from a small study. Treatment with qfFN at 200 ng/ml and 500 ng/ml resulted in lower cost savings per QALY lost relative to fFN at 50 ng/ml than treatment with Actim Partus. In contrast, qfFN at 10 ng/ml increased QALYs, by 0.002, and had a cost per QALY gained of £140,267 relative to fFN at 50 ng/ml. Similar qualitative results were obtained for women presenting at different gestational ages. CONCLUSION: There is a high degree of uncertainty surrounding the test accuracy and cost-effectiveness results. We are aware of four ongoing UK trials, two of which plan to enrol > 1000 participants. The results of these trials may significantly alter the findings presented here. STUDY REGISTRATION: The study is registered as PROSPERO CRD42017072696. FUNDING: The National Institute for Health Research Health Technology Assessment programme.

Infants may suffer from health problems if they are born early. If a mother has symptoms of labour before her baby is due, a test could be used to predict if the symptoms are real or a false alarm. A test could help the doctor to decide whether the mother needs treatment or to move to a specialist hospital or if she could be sent home (if it is a false alarm). Our report compares three tests [PartoSure™ (Parsagen Diagnostics Inc., Boston, MA, USA), Actim^® Partus (Medix Biochemica, Espoo, Finland) and the Fetal Fibronectin (fFN) Test (Hologic, Inc., Marlborough, MA, USA)] on how well they predict an early birth and how the costs and the long-term health outcomes of the child compare between and among tests. All the published literature reporting the accuracy of the three tests and their costs was reviewed. We developed a new cost-effectiveness model, which estimated the long-term health outcomes of the child based on the test results. Twenty of the studies reviewed looked at how good the tests were at predicting an early birth within the next 7 days, and six looked at predicting birth within 48 hours. The designs of the studies and the women taking part in the studies varied greatly. This meant that comparing the accuracy of the tests was very difficult and it would be unfair to decide which test was the best. Our model suggested no firm conclusions for the cost-effectiveness of fFN compared with Actim Partus. PartoSure appears to be less costly than Actim Partus and equally good at predicting preterm birth, but this is based on a study of very few patients. There were no data that allowed us to compare all three tests together. The accuracy of the results is uncertain, mainly because all the studies are very different. We are aware of four related UK trials that are currently ongoing that plan to include large numbers of women.