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1.
Bone Jt Open ; 4(2): 96-103, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-37051861

RESUMO

Early large treatment effects can arise in small studies, which lessen as more data accumulate. This study aimed to retrospectively examine whether early treatment effects occurred for two multicentre orthopaedic randomized controlled trials (RCTs) and explore biases related to this. Included RCTs were ProFHER (PROximal Fracture of the Humerus: Evaluation by Randomisation), a two-arm study of surgery versus non-surgical treatment for proximal humerus fractures, and UK FROST (United Kingdom Frozen Shoulder Trial), a three-arm study of two surgical and one non-surgical treatment for frozen shoulder. To determine whether early treatment effects were present, the primary outcome of Oxford Shoulder Score (OSS) was compared on forest plots for: the chief investigator's (CI) site to the remaining sites, the first five sites opened to the other sites, and patients grouped in quintiles by randomization date. Potential for bias was assessed by comparing mean age and proportion of patients with indicators of poor outcome between included and excluded/non-consenting participants. No bias in treatment effect was observed overall for the CI site, or the first five sites, compared with the remaining sites in either trial. An early treatment effect on the OSS was observed for the first quintile of participants recruited to ProFHER only (clinically relevant difference of seven points). Selection bias for age was observed in the ProFHER trial only, with slightly younger patients being recruited into the study. Both trials showed some selection bias for markers of poor prognosis, although these did not appear to change over time. No bias in treatment effects overall were found at the CI or early sites set-up. An early treatment effect was found in one of the two trials, which was likely a chance effect as this did not continue during the study. Selection bias was observed in both RCTs, however this was minimal and did not impact on outcome.

2.
Health Sci Rep ; 6(1): e1051, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36644312

RESUMO

Background and Aims: During the COVID-19 pandemic, US Food and Drug Administration (FDA) permitted emergency use authorizations (EUAs) for vaccines/treatments with promising data. Eight treatments were issued EUAs by May 31, 2021; one of these was approved (Remdesivir for certain populations) and two were revoked (chloroquine phosphate/hydroxychloroquine and bamlanivimab) by September 30, 2021. The aim of this study is to find out what evidence the EUAs were based on and how many studies were published while they remained active (up to September 30, 2021). Methods: A review of published clinical studies for the 6 months before each EUA was issued, and the time after (until September 30, 2021, or until revoked). PubMed and the identified systematic reviews were the sources for identifying published literature. Results: The number of clinical studies published pre-EUA varied from a single case study (for chloroquine phosphate/hydroxychloroquine) to numerous studies of multiple types (for convalescent plasma). Four treatments had a single randomized controlled trial (RCT) as evidence (bamlanivimab monotherapy, REGN-COV, bamlanivimab + etesevimab, sotrovimab) and two also had other study types (remdesivir and baricitinib). The number of clinical studies published post-EUA (for those active on September 30, 2021) was widely varied. Eighteen RCTs were published for Convalescent plasma, while Remdesivir had eight. Baricitinib, REGN-COV, and bamlanivimab + etesevimab all had one, but none were published for sotrovimab. Conclusion: The number of trials for treatments with EUAs was limited in all cases before the EUA was issued, and in most cases for those with EUAs ongoing at the end of September 2021. The presence of EUAs may discourage participation in relevant clinical trials, which delays the widespread implementation of evidenced-based therapies. Large, robust RCTs should be completed, such as the RECOVERY trial in the United Kingdom, to quickly find the answers desperately required during a pandemic.

3.
Res Methods Med Health Sci ; 4(2): 50-60, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38603296

RESUMO

Background: RCTs often face issues such as slow recruitment, poor intervention adherence and high attrition, however the 2020/2021 COVID-19 pandemic intensified these challenges. Strategies employed by the DISC trial to overcome pandemic-related barriers to recruitment, treatment delivery and retention may be useful to help overcome routine problems. Methods: A structured survey and teleconference with sites was undertaken. Key performance indicators in relation to recruitment, treatment delivery and retention were compared descriptively before and after the pandemic started. This was situated also in relation to qualitative opinions of research staff. Results: Prior to the pandemic, retention was 93.6%. Increased support from the central trial management team and remote data collection methods kept retention rates high at 81.2% in the first 6 months of the pandemic, rising to 89.8% in the subsequent 6 months. Advertising the study to patients resulted in 12.8 patients/month enquiring about participation, however only six were referred to recruiting sites. Sites reported increased support from junior doctors resolved research nurse capacity issues. One site avoided long delays by using theatre space in a private hospital. Conclusions: Recruitment post-pandemic could be improved by identification of barriers, increased support from junior doctors through the NIHR associate PI scheme and advertising. Remote back-up options for data collection can keep retention high while reducing patient and site burden. To future proof studies against similar disruptions and provide more flexibility for participants, we recommend that RCTs have a back-up option of remote recruitment, a back-up location for surgeries and flexible approaches to collecting data.

4.
Contemp Clin Trials ; 113: 106665, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34968767

RESUMO

OBJECTIVE: This review investigates whether the distribution of recruitment to multicentre randomised controlled trials (RCTs) fits the "Pareto Principle", i.e. 80% of participants are recruited by 20% of sites, or Price's Law, i.e. 50% of participants are recruited by the square root of the total number of sites. METHODS: A review of HTA reports published between 2017 and 2019. RESULTS: 40 RCTs conducted face-to-face recruitment, five recruited via mail-outs and one used both methods. For face-to-face recruitment (n = 41 studies), 80% of participants were recruited by the top recruiting 42.6% of sites; for mail-out methods (n = 6 studies) this was 52.0%. From the square root of sites, 51.3% and 31.8% of participants were recruited for the two recruitment approaches, respectively. Specifically, 3 (7.3%, 95% CI 2.5% to 19.4%) and 20 (48.8%, 95% CI 34.3% to 63.5%) RCTs that recruited face-to-face followed Pareto Principle and Price's Law, respectively. One mail-out recruitment study followed one of these principles, Price's Law. Chief Investigator (CI) sites (n = 24) in face-to-face recruitment studies recruited 18.1% of participants. CONCLUSION: Face-to-face recruitment to HTA-funded RCTs fits more closely to Price's Law than the Pareto Principle, with the CI's site recruiting nearly a fifth of participants. Since we focussed on HTA-funded RCTs with ≥9 recruiting sites and for which the recruitment method and number recruited by site were known, our findings are limited in their generalisability. However, this trend could be used as a guide to aid in estimating how many sites RCTs need. More accurate estimation may prevent the need for recruitment extensions.


Assuntos
Avaliação da Tecnologia Biomédica , Humanos , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Reino Unido
5.
Trials ; 22(1): 671, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34593024

RESUMO

BACKGROUND: Dupuytren's contracture is a fibro-proliferative disease of the hands affecting over 2 million UK adults, particularly the white, male population. Surgery is the traditional treatment; however, recent studies have indicated that an alternative to surgery-collagenase clostridium histolyticum (collagenase)-is better than a placebo in the treatment of Dupuytren's contracture. There is however no robust randomised controlled trial that provides a definitive answer on the clinical effectiveness of collagenase compared with limited fasciectomy surgery. Dupuytren's intervention surgery vs collagenase trial (DISC) trial was therefore designed to fill this evidence gap. METHODS/DESIGN: The DISC trial is a multi-centre pragmatic two-arm parallel-group, randomised controlled trial. Participants will be assigned 1:1 to receive either collagenase injection or surgery (limited fasciectomy). We aim to recruit 710 adult participants with Dupuytren's contracture. Potential participants will be identified in primary and secondary care, screened by a delegated clinician and if eligible and consenting, baseline data will be collected and randomisation completed. The primary outcome will be the self-reported patient evaluation measure assessed 1 year after treatment. Secondary outcome measures include the Unité Rhumatologique des Affections de la Main Scale, the Michigan Hand Questionnaire, EQ-5D-5L, resource use, further procedures, complications, recurrence, total active movement and extension deficit, and time to return to function. Given the limited evidence comparing recurrence rates following collagenase injection and limited fasciectomy, and the importance of a return to function as soon as possible for patients, the associated measures for each will be prioritised to allow treatment effectiveness in the context of these key elements to be assessed. An economic evaluation will assess the cost-effectiveness of treatments, and a qualitative sub-study will assess participants' experiences and preferences of the treatments. DISCUSSION: The DISC trial is the first randomised controlled trial, to our knowledge, to investigate the clinical and cost-effectiveness of collagenase compared to limited fasciectomy surgery for patients with Dupuytren's contracture. TRIAL REGISTRATION: Clinical.Trials.gov ISRCTN18254597 . Registered on April 11, 2017.


Assuntos
Contratura de Dupuytren , Recidiva Local de Neoplasia , Adulto , Colagenases/efeitos adversos , Contratura de Dupuytren/diagnóstico , Contratura de Dupuytren/tratamento farmacológico , Contratura de Dupuytren/cirurgia , Fasciotomia , Humanos , Masculino , Colagenase Microbiana/efeitos adversos , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
NPJ Breast Cancer ; 7(1): 38, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33824328

RESUMO

Triple-negative breast cancer (TNBC) remains the most lethal breast cancer subtype with poor response rates to the current chemotherapies and a lack of additional effective treatment options. We have identified deoxyuridine 5'-triphosphate nucleotidohydrolase (dUTPase) as a critical gatekeeper that protects tumour DNA from the genotoxic misincorporation of uracil during treatment with standard chemotherapeutic agents commonly used in the FEC regimen. dUTPase catalyses the hydrolytic dephosphorylation of deoxyuridine triphosphate (dUTP) to deoxyuridine monophosphate (dUMP), providing dUMP for thymidylate synthase as part of the thymidylate biosynthesis pathway and maintaining low intracellular dUTP concentrations. This is crucial as DNA polymerase cannot distinguish between dUTP and deoxythymidylate triphosphate (dTTP), leading to dUTP misincorporation into DNA. Targeting dUTPase and inducing uracil misincorporation during the repair of DNA damage induced by fluoropyrimidines or anthracyclines represents an effective strategy to induce cell lethality. dUTPase inhibition significantly sensitised TNBC cell lines to fluoropyrimidines and anthracyclines through imbalanced nucleotide pools and increased DNA damage leading to decreased proliferation and increased cell death. These results suggest that repair of treatment-mediated DNA damage requires dUTPase to prevent uracil misincorporation and that inhibition of dUTPase is a promising strategy to enhance the efficacy of TNBC chemotherapy.

7.
Ther Adv Med Oncol ; 12: 1758835920906047, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32215056

RESUMO

BACKGROUND: Triple negative breast cancer (TNBC) is the subset of breast cancer associated with the poorest outcome, and currently lacks targeted treatments. Standard of care (SoC) chemotherapy often consists of DNA damaging chemotherapies ± taxanes, with a range of responses observed. However, we currently lack biomarkers to predict this response and lack alternate treatment options. METHODS: Pin1 expression was modulated in vitro and proliferation and treatment response was studied. Pin1 expression was analysed in patient samples and correlated with clinical outcome. RESULTS: In this study, we have shown that the prolyl isomerase, Pin1, which is highly expressed in TNBC, plays a key role in pathogenesis of the disease. Knockdown of Pin1 in TNBC resulted in cell death while the opposite is seen in normal cells. We revealed for the first time that loss of Pin1 leads to increased sensitivity to Taxol but only in the absence of functional BRCA1. Conversely, loss of Pin1 results in decreased sensitivity to DNA-damaging agents independent of BRCA1 status. Analysis of Pin1 gene or IHC-based expression in over 200 TNBC patient samples revealed a novel role for Pin1 as a TNBC-specific biomarker, with high expression associated with improved outcome in the context of SoC chemotherapy. Preliminary data indicated this may be extended to other treatment options (e.g. Cisplatin/Parp Inhibitors) that are gaining traction for the treatment of TNBC. CONCLUSIONS: This study highlights the important role played by Pin1 in TNBC and highlights the context-dependent functions in modulating cell growth and response to treatment.

8.
F1000Res ; 9: 1017, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33447376

RESUMO

The RECOVERY trial is a large multi-armed, adaptive randomised controlled trial of treatments for Covid-19.  It has rapidly recruited and demonstrated that hydroxychloroquine is ineffective in reducing mortality for hospitalised patients, whilst dexamethasone significantly reduces mortality among those patients using supplemental oxygen or on a ventilator.  We estimate that the speed of recruitment and dissemination has probably decreased mortality in the UK by at least 200 hospitalised patients in the first month since the British Prime Minister announced the results.  Despite its impressive speed, the trial only recruited about 10-15% of eligible patients, with recruitment rates ranging between 3% to 80% at participating hospitals.  Had the trial recruited 50% of the eligible patients then our analysis suggests that more than 2,000 additional lives could have been saved.  In a pandemic, rapid recruitment with high centre recruitment is absolutely essential to reduce deaths.  Methods of improving site specific recruitment rates need investigating urgently.


Assuntos
COVID-19/mortalidade , Seleção de Pacientes , COVID-19/terapia , Dexametasona/uso terapêutico , Humanos , Hidroxicloroquina , Estudos Multicêntricos como Assunto , Pandemias , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Reino Unido/epidemiologia
9.
Cell Rep ; 25(13): 3674-3692.e10, 2018 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-30590041

RESUMO

The SRC-family kinase LYN is highly expressed in triple-negative/basal-like breast cancer (TNBC) and in the cell of origin of these tumors, c-KIT-positive luminal progenitors. Here, we demonstrate LYN is a downstream effector of c-KIT in normal mammary cells and protective of apoptosis upon genotoxic stress. LYN activity is modulated by PIN1, a prolyl isomerase, and in BRCA1 mutant TNBC PIN1 upregulation activates LYN independently of c-KIT. Furthermore, the full-length LYN splice isoform (as opposed to the Δaa25-45 variant) drives migration and invasion of aggressive TNBC cells, while the ratio of splice variants is informative for breast cancer-specific survival across all breast cancers. Thus, dual mechanisms-uncoupling from upstream signals and splice isoform ratios-drive the activity of LYN in aggressive breast cancers.


Assuntos
Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Quinases da Família src/metabolismo , Adolescente , Adulto , Animais , Proteína BRCA1/deficiência , Proteína BRCA1/metabolismo , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Isoenzimas/metabolismo , Camundongos , Peptidilprolil Isomerase de Interação com NIMA/metabolismo , Invasividade Neoplásica , Proteínas Proto-Oncogênicas c-kit/metabolismo , Splicing de RNA/genética , Análise de Sobrevida , Regulação para Cima , Adulto Jovem , Quinases da Família src/genética
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