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1.
Drug Saf ; 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824267

RESUMEN

BACKGROUND AND OBJECTIVES: Key opinion leader (KOL) interviews were conducted by the Benefit-Risk Assessment Planning (BRAP) Taskforce to seek expert opinion mainly from industry and regulatory bodies, about the current status and future direction of benefit-risk assessment (BRA) planning in the lifecycle of medical product development. The findings from these interviews are intended to help communication concerning planning for BRA between industry and regulators and shape future guidance. METHODS: Key opinion leader interviews consisted of 5 questions related to BRA planning, which were administered to volunteers (mainly clinicians and statisticians) within a pool of experienced pharmaceutical and medical device professionals representing academia, industry, regulatory agencies and a patient group. The interviewees' responses to the 5 questions were summarized. To analyze the qualitative data, a Coding System was developed to label themes arising from the interviews. The key findings from the interviews were summarized into a Master Template. A quantitative analysis based on descriptive statistics was also conducted. RESULTS: Of the 27 interviewees, there were 11 professionals from regulatory agencies, 11 from industry, 4 from academia and 1 from a patient advocacy group. Key findings based on the comments provided by 48% of the interviewees indicated the need of incorporating BRA into other (e.g., existing) processes with the importance of alignment between processes being stressed in the comments provided by 59% of the interviewees. Commencing BRA early in the product lifecycle was emphasized in comments provided by 44% of the interviewees. Among other needs identified were an appropriate contextualization of benefits and risks (based on comments provided by 41% of interviewees) through adoption of an integrated approach with structured support by regulatory agencies and a need for understanding the audience with better communication of benefit-risk (BR) among all stakeholders (based on comments provided by 44% of the interviewees). Almost all comments provided by interviewees (96%) highlighted the importance of utilizing patient experience/preference to guide new product development and BRA. Comments provided by 74% of the interviewees expressed the need to understand patient tolerance for risk and trade-offs, with a majority (78%) of interviewees highlighting how to gather information, and 59% stressing the need for the selection and development of appropriate methodologies as important considerations for enhancing the quality and relevance of the data collected from patients. CONCLUSIONS: Interviewees indicated that BRA should commence early in the medical product development and inform decision-making throughout the product lifecycle. Better planning and integration of BRA into existing processes within industry would be valuable. The importance of incorporating the patient voice into BRA and medical product development was emphasized. Other key findings from the KOL interviews included a need for improved communication of BR information, and establishment of methodologies for performing BRA and soliciting patient input.

2.
Pharmaceut Med ; 37(3): 171-181, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37072647

RESUMEN

Aggregate safety assessment involves evaluation of the totality of safety data to characterize the emerging safety profile of a product. The Drug Information Association-American Statistical Association Interdisciplinary Safety Evaluation scientific working group recently published an approach to developing an Aggregate Safety Assessment Plan (ASAP). Creation of an ASAP facilitates a consistent approach to safety data collection and analysis across studies and minimizes important missing data at the time of regulatory submission. A critical aspect of the ASAP is identification of the Safety Topics of Interest (STOI). The STOI, as defined in the ASAP, comprises adverse events (AEs), which have the potential to impact the benefit: risk profile of a product and typically require specialized data collection or analyses. While there are clear benefits to developing an ASAP for a drug development program, multiple concerns may be encountered with implementation. This article uses the examples of two STOIs to demonstrate the benefits and efficiencies gained with implementation of the ASAP in safety planning as well as in optimally characterizing the emerging safety profile of a product.


Asunto(s)
Sistemas de Registro de Reacción Adversa a Medicamentos , Recolección de Datos , Recolección de Datos/métodos , Estados Unidos , Sistemas de Registro de Reacción Adversa a Medicamentos/organización & administración
3.
Materials (Basel) ; 15(17)2022 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-36079191

RESUMEN

Chirality depends on particular symmetries. For crystal structures it describes the absence of mirror planes and inversion centers, and in addition to translations, only rotations are allowed as symmetry elements. However, chiral space groups have additional restrictions on the allowed screw rotations as a symmetry element, because they always appear in enantiomorphous pairs. This study classifies and distinguishes the chiral structures and space groups. Chirality is quantified using Hausdorff distances and continuous chirality measures and selected crystal structures are reported. Chirality is discussed for bulk solids and their surfaces. Moreover, the band structure, and thus, the density of states, is found to be affected by the same crystal parameters as chirality. However, it is independent of handedness. The Berry curvature, as a topological measure of the electronic structure, depends on the handedness but is not proof of chirality because it responds to the inversion of a structure. For molecules, optical circular dichroism is one of the most important measures for chirality. Thus, it is proposed in this study that the circular dichroism in the angular distribution of photoelectrons in high symmetry configurations can be used to distinguish the handedness of chiral solids and their surfaces.

4.
Front Pharmacol ; 10: 1395, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31849657

RESUMEN

Objectives: To investigate stakeholder perspectives on how patient preference studies (PPS) should be designed and conducted to allow for inclusion of patient preferences in decision-making along the medical product life cycle (MPLC), and how patient preferences can be used in such decision-making. Methods: Two literature reviews and semi-structured interviews (n = 143) with healthcare stakeholders in Europe and the US were conducted; results of these informed the design of focus group guides. Eight focus groups were conducted with European patients, industry representatives and regulators, and with US regulators and European/Canadian health technology assessment (HTA) representatives. Focus groups were analyzed thematically using NVivo. Results: Stakeholder perspectives on how PPS should be designed and conducted were as follows: 1) study design should be informed by the research questions and patient population; 2) preferred treatment attributes and levels, as well as trade-offs among attributes and levels should be investigated; 3) the patient sample and method should match the MPLC phase; 4) different stakeholders should collaborate; and 5) results from PPS should be shared with relevant stakeholders. The value of patient preferences in decision-making was found to increase with the level of patient preference sensitivity of decisions on medical products. Stakeholders mentioned that patient preferences are hardly used in current decision-making. Potential applications for patient preferences across industry, regulatory and HTA processes were identified. Four applications seemed most promising for systematic integration of patient preferences: 1) benefit-risk assessment by industry and regulators at the marketing-authorization phase; 2) assessment of major contribution to patient care by European regulators; 3) cost-effectiveness analysis; and 4) multi criteria decision analysis in HTA. Conclusions: The value of patient preferences for decision-making depends on the level of collaboration across stakeholders; the match between the research question, MPLC phase, sample, and preference method used in PPS; and the sensitivity of the decision regarding a medical product to patient preferences. Promising applications for patient preferences should be further explored with stakeholders to optimize their inclusion in decision-making.

5.
Front Pharmacol ; 10: 1009, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31619989

RESUMEN

Objectives: Patient preference information (PPI) is gaining recognition among the pharmaceutical industry, regulatory authorities, and health technology assessment (HTA) bodies/payers for use in assessments and decision-making along the medical product lifecycle (MPLC). This study aimed to identify factors and situations that influence the value of patient preference studies (PPS) in decision-making along the MPLC according to different stakeholders. Methods: Semi-structured interviews (n = 143) were conducted with six different stakeholder groups (physicians, academics, industry representatives, regulators, HTA/payer representatives, and a combined group of patients, caregivers, and patient representatives) from seven European countries (the United Kingdom, Sweden, Italy, Romania, Germany, France, and the Netherlands) and the United States. Framework analysis was performed using NVivo 11 software. Results: Fifteen factors affecting the value of PPS in the MPLC were identified. These are related to: study organization (expertise, financial resources, study duration, ethics and good practices, patient centeredness), study design (examining patient and/or other preferences, ensuring representativeness, matching method to research question, matching method to MPLC stage, validity and reliability, cognitive burden, patient education, attribute development), and study conduct (patients' ability/willingness to participate and preference heterogeneity). Three types of situations affecting the use of PPS results were identified (stakeholder acceptance, market situations, and clinical situations). Conclusion: The factors and situation types affecting the value of PPS, as identified in this study, need to be considered when designing and conducting PPS in order to promote the integration of PPI into decision-making along the MPLC.

6.
BMC Med Inform Decis Mak ; 19(1): 189, 2019 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-31585538

RESUMEN

BACKGROUND: The inclusion of patient preferences (PP) in the medical product life cycle is a topic of growing interest to stakeholders such as academics, Health Technology Assessment (HTA) bodies, reimbursement agencies, industry, patients, physicians and regulators. This review aimed to understand the potential roles, reasons for using PP and the expectations, concerns and requirements associated with PP in industry processes, regulatory benefit-risk assessment (BRA) and marketing authorization (MA), and HTA and reimbursement decision-making. METHODS: A systematic review of peer-reviewed and grey literature published between January 2011 and March 2018 was performed. Consulted databases were EconLit, Embase, Guidelines International Network, PsycINFO and PubMed. A two-step strategy was used to select literature. Literature was analyzed using NVivo (QSR international). RESULTS: From 1015 initially identified documents, 72 were included. Most were written from an academic perspective (61%) and focused on PP in BRA/MA and/or HTA/reimbursement (73%). Using PP to improve understanding of patients' valuations of treatment outcomes, patients' benefit-risk trade-offs and preference heterogeneity were roles identified in all three decision-making contexts. Reasons for using PP relate to the unique insights and position of patients and the positive effect of including PP on the quality of the decision-making process. Concerns shared across decision-making contexts included methodological questions concerning the validity, reliability and cognitive burden of preference methods. In order to use PP, general, operational and quality requirements were identified, including recognition of the importance of PP and ensuring patient understanding in PP studies. CONCLUSIONS: Despite the array of opportunities and added value of using PP throughout the different steps of the MPLC identified in this review, their inclusion in decision-making is hampered by methodological challenges and lack of specific guidance on how to tackle these challenges when undertaking PP studies. To support the development of such guidance, more best practice PP studies and PP studies investigating the methodological issues identified in this review are critically needed.


Asunto(s)
Equipos y Suministros , Prioridad del Paciente , Toma de Decisiones , Humanos , Reproducibilidad de los Resultados , Medición de Riesgo , Evaluación de la Tecnología Biomédica
7.
Patient ; 12(5): 513-526, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31222436

RESUMEN

BACKGROUND: Patient preferences (PP), which are investigated in PP studies using qualitative or quantitative methods, are a growing area of interest to the following stakeholders involved in the medical product lifecycle: academics, health technology assessment bodies, payers, industry, patients, physicians, and regulators. However, the use of PP in decisions along the medical product lifecycle remains limited. As the adoption of PP heavily relies on these stakeholders, knowledge of their perceptions of PP is critical. OBJECTIVE: This study aimed to characterize stakeholders' attitudes, needs, and concerns with respect to PP in decision making along the medical product lifecycle. METHODS: Semi-structured interviews (n = 143) were conducted with academics (n = 24), health technology assessment/payer representatives (n = 24), industry representatives (n = 24), patients, caregivers and patient representatives (n = 24), physicians (n = 24), and regulators (n = 23) from seven European countries and the USA. Interviews were conducted between April and August 2017. The framework method was used to organize the data and identify themes and key findings in each interviewed stakeholder group. RESULTS: Interviewees reported being unfamiliar (43%), moderately familiar (42%), or very familiar (15%) with preference methods and studies. Interviewees across stakeholder groups generally supported the idea of using PP in the medical product lifecycle but expressed mixed opinions about the feasibility and impact of using PP in decision making. Interviewees from all stakeholder groups stressed the importance of increasing stakeholders' understanding of the concept of PP and preference methods and ensuring patients' understanding of the questions asked in PP studies. Key concerns and needs in each interviewed stakeholder group were as follows: (1) academics: investigating the validity, reliability, reproducibility, and generalizability of preference methods; (2) health technology assessment/payer representatives: developing quality criteria for evaluating PP studies and gaining insights into how to weigh them in reimbursement/payer decision making; (3) industry representatives: obtaining guidance on PP studies and recognition on the importance of PP from decision makers; (4) patients, caregivers, and patient representatives: providing an incentive and adequate information towards patients when participating in PP studies; (5) physicians: avoiding bias as a result of commercial agendas in PP studies and clarifying how to deal with subjective and emotional elements when measuring PP; and (6) regulators: avoiding the misuse of PP study results to overrule the traditional efficacy and safety criteria used for marketing authorization and obtaining robust PP study results. CONCLUSIONS: Despite the interest all interviewed stakeholder groups reported in PP, the effective use of PP in decision making across the medical product lifecycle is currently hampered by a lack of standardization and consensus on how to both measure and use PP.


Asunto(s)
Prioridad del Paciente , Participación de los Interesados/psicología , Evaluación de la Tecnología Biomédica , Toma de Decisiones , Europa (Continente) , Femenino , Humanos , Entrevistas como Asunto , Masculino , Investigación Cualitativa , Estados Unidos
8.
Phys Rev Lett ; 122(5): 059901, 2019 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-30822019

RESUMEN

This corrects the article DOI: 10.1103/PhysRevLett.110.100401.

9.
Drug Discov Today ; 24(1): 57-68, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30266656

RESUMEN

Industry, regulators, health technology assessment (HTA) bodies, and payers are exploring the use of patient preferences in their decision-making processes. In general, experience in conducting and assessing patient preference studies is limited. Here, we performed a systematic literature search and review to identify factors and situations influencing the value of patient preference studies, as well as applications throughout the medical product lifecyle. Factors and situations identified in 113 publications related to the organization, design, and conduct of studies, and to communication and use of results. Although current use of patient preferences is limited, we identified possible applications in discovery, clinical development, marketing authorization, HTA, and postmarketing phases.


Asunto(s)
Prioridad del Paciente , Comunicación , Equipos y Suministros , Humanos , Preparaciones Farmacéuticas , Proyectos de Investigación
10.
Proc Natl Acad Sci U S A ; 115(37): 9140-9144, 2018 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-30154165

RESUMEN

Topological materials ranging from topological insulators to Weyl and Dirac semimetals form one of the most exciting current fields in condensed-matter research. Many half-Heusler compounds, RPtBi (R = rare earth), have been theoretically predicted to be topological semimetals. Among various topological attributes envisaged in RPtBi, topological surface states, chiral anomaly, and planar Hall effect have been observed experimentally. Here, we report an unusual intrinsic anomalous Hall effect (AHE) in the antiferromagnetic Heusler Weyl semimetal compounds GdPtBi and NdPtBi that is observed over a wide temperature range. In particular, GdPtBi exhibits an anomalous Hall conductivity of up to 60 Ω-1⋅cm-1 and an anomalous Hall angle as large as 23%. Muon spin-resonance (µSR) studies of GdPtBi indicate a sharp antiferromagnetic transition (TN) at 9 K without any noticeable magnetic correlations above TN Our studies indicate that Weyl points in these half-Heuslers are induced by a magnetic field via exchange splitting of the electronic bands at or near the Fermi energy, which is the source of the chiral anomaly and the AHE.

11.
Sci Adv ; 2(4): e1501870, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27152355

RESUMEN

It is well established that the anomalous Hall effect displayed by a ferromagnet scales with its magnetization. Therefore, an antiferromagnet that has no net magnetization should exhibit no anomalous Hall effect. We show that the noncolinear triangular antiferromagnet Mn3Ge exhibits a large anomalous Hall effect comparable to that of ferromagnetic metals; the magnitude of the anomalous conductivity is ~500 (ohm·cm)(-1) at 2 K and ~50 (ohm·cm)(-1) at room temperature. The angular dependence of the anomalous Hall effect measurements confirms that the small residual in-plane magnetic moment has no role in the observed effect except to control the chirality of the spin triangular structure. Our theoretical calculations demonstrate that the large anomalous Hall effect in Mn3Ge originates from a nonvanishing Berry curvature that arises from the chiral spin structure, and that also results in a large spin Hall effect of 1100 (h/e) (ohm·cm)(-1), comparable to that of platinum. The present results pave the way toward the realization of room temperature antiferromagnetic spintronics and spin Hall effect-based data storage devices.


Asunto(s)
Germanio/química , Imanes/química , Manganeso/química , Estructura Molecular
12.
J Phys Condens Matter ; 25(20): 206006, 2013 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-23628865

RESUMEN

We investigate the structural stability and magnetic properties of the cubic, tetragonal and hexagonal phases of Mn3Z (Z=Ga, Sn and Ge) Heusler compounds using first-principles density-functional theory. We propose that the cubic phase plays an important role as an intermediate state in the phase transition from the hexagonal to the tetragonal phases. Consequently, Mn3Ga and Mn3Ge behave differently from Mn3Sn, because the relative energies of the cubic and hexagonal phases are different. This result agrees with experimental observations for these three compounds. The weak ferromagnetism of the hexagonal phase and the perpendicular magnetocrystalline anisotropy of the tetragonal phase obtained in our calculations are also consistent with experiment.

13.
Phys Rev Lett ; 110(10): 100401, 2013 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-23521232

RESUMEN

Recent studies have reported an interesting class of semiconductor materials that bridge the gap between semiconductors and half-metallic ferromagnets. These materials, called spin gapless semiconductors, exhibit a band gap in one of the spin channels and a zero band gap in the other and thus allow for tunable spin transport. Here, we report the first experimental verification of the spin gapless magnetic semiconductor Mn(2)CoAl, an inverse Heusler compound with a Curie temperature of 720 K and a magnetic moment of 2 µ(B). Below 300 K, the compound exhibits nearly temperature-independent conductivity, very low, temperature-independent carrier concentration, and a vanishing Seebeck coefficient. The anomalous Hall effect is comparatively low, which is explained by the symmetry properties of the Berry curvature. Mn(2) CoAl is not only suitable material for room temperature semiconductor spintronics, the robust spin polarization of the spin gapless semiconductors makes it very promising material for spintronics in general.

14.
Adv Mater ; 24(47): 6283-7, 2012 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-22965466

RESUMEN

Band Jahn-Teller type structural instabilities of cubic Mn(2)YZ Heusler compounds causing tetragonal distortions can be predicted by ab initio band-structure calculations. This allows for identification of new Heusler materials with tunable magnetic and structural properties that can satisfy the demands for spintronic applications, such as in spin-transfer torque-based devices.

15.
Angew Chem Int Ed Engl ; 51(29): 7221-5, 2012 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-22684869

RESUMEN

Heavy stuff: Topological insulators are formed of heavy atoms and host special surface or edge states. The electronic structure is characterized by a Dirac cone within a bulk band gap (see picture) that is generated by strong spin-orbit coupling. A chemist's perspective in terms of bonds, bands, symmetry, and nuclear charge is provided.

16.
Phys Rev Lett ; 106(15): 156402, 2011 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-21568583

RESUMEN

We investigate a new class of ternary materials such as LiAuSe and KHgSb with a honeycomb structure in Au-Se and Hg-Sb layers. We demonstrate the band inversion in these materials similar to HgTe, which is a strong precondition for existence of the topological surface states. In contrast with graphene, these materials exhibit strong spin-orbit coupling and a small direct band gap at the Γ point. Since these materials are centrosymmetric, it is straightforward to determine the parity of their wave functions, and hence their topological character. Surprisingly, the compound with strong spin-orbit coupling (KHgSb) is trivial, whereas LiAuSe is found to be a topological insulator.

17.
Nat Mater ; 9(7): 541-5, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20512154

RESUMEN

Recently the quantum spin Hall effect was theoretically predicted and experimentally realized in quantum wells based on the binary semiconductor HgTe (refs 1-3). The quantum spin Hall state and topological insulators are new states of quantum matter interesting for both fundamental condensed-matter physics and material science. Many Heusler compounds with C1(b) structure are ternary semiconductors that are structurally and electronically related to the binary semiconductors. The diversity of Heusler materials opens wide possibilities for tuning the bandgap and setting the desired band inversion by choosing compounds with appropriate hybridization strength (by the lattice parameter) and magnitude of spin-orbit coupling (by the atomic charge). Based on first-principle calculations we demonstrate that around 50 Heusler compounds show band inversion similar to that of HgTe. The topological state in these zero-gap semiconductors can be created by applying strain or by designing an appropriate quantum-well structure, similar to the case of HgTe. Many of these ternary zero-gap semiconductors (LnAuPb, LnPdBi, LnPtSb and LnPtBi) contain the rare-earth element Ln, which can realize additional properties ranging from superconductivity (for example LaPtBi; ref. 12) to magnetism (for example GdPtBi; ref. 13) and heavy fermion behaviour (for example YbPtBi; ref. 14). These properties can open new research directions in realizing the quantized anomalous Hall effect and topological superconductors.

18.
Phys Rev Lett ; 102(1): 016401, 2009 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-19257217

RESUMEN

We report on theoretical investigations of the exotic magnetism in rubidium sesquioxide Rb4O6, a model correlated system with an open 2p shell. Experimental investigations indicated that Rb4O6 is a magnetically frustrated insulator. The frustration is explained here by electronic structure calculations that incorporate the correlation between the oxygen 2p electrons and deal with the mixed-valent oxygen. This leads to a physical picture where the symmetry is reduced because one third of the oxygen in Rb4O6 is nonmagnetic while the remaining two thirds assemble in antiferromagnetic arrangements. A degenerate, insulating ground state with a large number of frustrated noncollinear magnetic configurations is confidently deduced from the theoretical point of view. These findings demonstrate in general the importance of electron-electron correlations in open-shell p-electron systems.

19.
Sci Technol Adv Mater ; 9(1): 014102, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27877928

RESUMEN

Spintronic is a multidisciplinary field and a new research area. New materials must be found for satisfying the different types of demands. The search for stable half-metallic ferromagnets and ferromagnetic semiconductors with Curie temperatures higher than room temperature is still a challenge for solid state scientists. A general understanding of how structures are related to properties is a necessary prerequisite for material design. Computational simulations are an important tool for a rational design of new materials. The new developments in this new field are reported from the point of view of material scientists. The development of magnetic Heusler compounds specifically designed as material for spintronic applications has made tremendous progress in the very recent past. Heusler compounds can be made as half-metals, showing a high spin polarization of the conduction electrons of up to 100% in magnetic tunnel junctions. High Curie temperatures were found in Co2-based Heusler compounds with values up to 1120 K in Co2FeSi. The latest results at the time of writing are a tunnelling magnet resistance (TMR) device made from the Co2FeAl0.5Si0.5 Heusler compound and working at room temperature with a (TMR) effect higher than 200%. Good interfaces and a well-ordered compound are the precondition to realize the predicted half-metallic properties. The series Co2FeAl1- x Si x is found to exhibit half-metallic ferromagnetism over a broad range, and it is shown that electron doping stabilizes the gap in the minority states for x=0.5. This might be a reason for the exceptional temperature behaviour of Co2FeAl0.5Si0.5 TMR devices. Using x-ray diffraction (XRD), it was shown conclusively that Co2FeAl crystallizes in the B2 structure whereas Co2FeSi crystallizes in the L21 structure. For the compounds Co2FeGa or Co2FeGe, with Curie temperatures expected higher than 1000 K, the standard XRD technique using laboratory sources cannot be used to easily distinguish between the two structures. For this reason, the EXAFS technique was used to elucidate the structure of these two compounds. Analysis of the data indicated that both compounds crystallize in the L21 structure which makes these two compounds suitable new candidates as materials in magnetic tunnel junctions.

20.
Stat Med ; 26(7): 1518-31, 2007 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-16903003

RESUMEN

In each clinical trial the statistical evaluation of adverse events (AEs) is a major part of standard safety analyses. However, the analyses of AEs usually lack from adequately accounting for the occurrence of multiple, different AEs. Furthermore, predictive variables other than treatment such as age, sex and concomitant medication are often ignored. These issues can be addressed by the Cox regression as introduced by Andersen and Gill and Wei et al. A further issue arises from the fact that an ordered programme of studies is conducted during clinical testing of pharmaceutical drugs. In this paper, we therefore discuss a stratified multivariate Cox regression model that can be used in integrated summaries of safety. We derive partial maximum likelihood estimators of the model parameters which can be shown to be consistent and asymptotically normally distributed. Mainly based on a sandwich estimator of their covariance matrix several test statistics are proposed that can be used to test various null hypotheses on the underlying parameters. Their asymptotic null distributions are given. The benefit of this survival time approach for analysing AEs is illustrated by evaluating symptoms of common cold from the database of a clinical development project.


Asunto(s)
Ensayos Clínicos como Asunto/métodos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Análisis Multivariante , Modelos de Riesgos Proporcionales , Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de la Colinesterasa/efectos adversos , Inhibidores de la Colinesterasa/uso terapéutico , Resfriado Común/inducido químicamente , Humanos , Metaanálisis como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos
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