Impact of vascular morphology and plaque characteristics on computed tomography derived fractional flow reserve in early stage coronary artery disease

Background

FFRCT gradually decreases from the proximal to the distal part of a vessel and reach the pathological threshold for significant ischemia even in the absence of obstructive coronary artery disease (CAD). The exact mechanisms of such gradual FFRCT decline remain unknown.

Purpose

The aims of this study are (1) to clarify the mechanisms of the gradual decline of computed tomography (CT) derived fractional flow reserve (FFRCT); and (2) to identify the predictive factors of an FFRCT decline below the pathological value of 0.80 in no apparent CAD vessels.

Methods

A total of 1058 outpatients with suspected CAD and who underwent CT angiography (CTA) with FFRCT analysis between January 2017 and December 2019 were evaluated. Among them, 150 consecutive patients who had both a CTA coupled to an FFRCT analysis and an invasive angiogram showing <25% coronary stenosis were included for analysis. Vessels were divided into two groups according to FFRCT at the distal vessel: FFRCT >0.80 (n=317) and FFRCT ≤0.80 (n=114). ΔFFRCT was defined as the magnitude of the change in FFRCT from the proximal to the distal vessel. Plaque characterization and vessel morphology measurements were performed semi-automatically. Vessel constituents were characterized based on Hounsfield units (HU) into lumen volume (<−50 HU), non-calcified plaque (NCP) (−50–150 HU), and calcified plaque (>150 HU).

Results

FFRCT decreased continuously from the proximal to distal across the three major vessels in both FFRCT>0.80 and FFRCT ≤0.80 groups (Figure 1). Compared to FFRCT>0.80 group, NCP volume was significantly higher in all three major vessels in FFRCT ≤0.80 group (210.2±83.6 mm3 vs. 140.9±139.3 mm3 for the RCA, p=0.01; 177.5±150.2 mm3 vs. 133.2±112.2 mm3 for the LAD, p=0.04; 127.6±91.5 mm3 vs. 58.7±57.7 mm3 for the LCX, p<0.01). Next, we investigated the vessel parameters that correlated with ΔFFRCT. ΔFFRCT was correlated with lumen volume in FFRCT>0.80 group (r=−0.24, p<0.0001), whereas ΔFFRCT was correlated with NCP volume in FFRCT ≤0.80 group (r=0.42, p<0.001) (Figure 2). An NCP volume above 44.8 mm3 was the strongest predictor of distal FFRCT of ≤0.80 (area under the curve 0.69, p<0.0001, sensitivity 95%, specificity 39%).

Conclusions

FFRCT is affected by vascular morphology and plaque characteristics even in the early stage of coronary artery disease. Our study highlights that subclinical coronary artery disease strongly influences FFRCT by effects unrelated to coronary stenosis. The presence of NCP is a major predictor of the gradual decrease of FFRCT toward pathological values. Anatomical findings as vessel morphology and plaque characteristics should be taken into consideration when interpreting numerical values of FFRCT to avoid unnecessary referrals for invasive coronary angiography or percutaneous coronary intervention.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Cost effectiveness of romosozumab versus teriparatide for severe postmenopausal osteoporosis in Japan

This study assessed the cost effectiveness of romosozumab versus teriparatide, both sequenced to alendronate, for the treatment of severe postmenopausal osteoporosis in Japan, using bone mineral density (BMD) efficacy data. Results show that romosozumab/alendronate produces greater health benefits at a lower cost than teriparatide/alendronate.

INTRODUCTION

This study aims to assess the cost effectiveness of romosozumab versus teriparatide, both sequenced to alendronate, for the treatment of severe postmenopausal osteoporosis in Japanese women previously treated with bisphosphonates.

METHODS

A Markov model was used to assess the relative cost effectiveness of 1 year of romosozumab versus 2 years of teriparatide, both sequenced to alendronate for a total treatment duration of 5 years. Outcomes for a cohort of women with a mean age of 78 years, a T-score ≤-2.5 and a previous fragility fracture were simulated over a lifetime horizon. The analysis was conducted from the perspective of the Japanese healthcare system and used a discount rate of 2% per annum. To inform relative fracture incidence, the bone mineral density (BMD) advantage of romosozumab over teriparatide was translated into relative risks of fracture, using relationships provided by a meta-regression of osteoporosis therapy trials. Outcomes were assessed in terms of lifetime costs (2020 US dollars) and quality-adjusted life years (QALYs).

RESULTS

Base case results showed that, compared with teriparatide/alendronate, romosozumab/alendronate reduced costs by $5134 per patient and yielded 0.045 additional QALYs. Scenario analyses and probabilistic sensitivity analysis confirmed that results are robust to uncertainty in model assumptions and inputs.

CONCLUSION

Results show that romosozumab/alendronate produces greater health benefits at a lower total cost than teriparatide/alendronate.

Broadband infrared light source by simultaneous parametric down-conversion

Spontaneous parametric down-conversion is an essential tool for a quantum light source in the infrared region ranging 2-5 µm for the purpose of material identification, chemical analysis, and gas sensing. So far, photon pairs from the process in a nonlinear crystal have low tunability and a narrow spectral range because of the phase-matching condition. Here, we propose a novel type of spontaneous parametric down-conversion processes that overcomes these challenges, where two photon pairs are simultaneously produced in the visible and infrared regions in periodically poled stoichiometric lithium tantalite. It allows broadband and tunable generation of infrared photon pairs that can be employed as an alternative light source for quantum infrared spectroscopy.

Risk factors for thrombocytopenia and analysis of time to platelet transfusion after azacitidine treatment

The use of azacitidine (AZA) has been known to lead to a high incidence of hematotoxic adverse events. The aims of this study were to identify the risk factors for thrombocytopenia after the administration of AZA and to analyze time to the initial platelet transfusion. Sixty-two patients with myelodysplastic syndrome (MDS), who were treated with AZA in Gifu Municipal Hospital between March 2012 and June 2020, were included in this study. The risk factors for thrombocytopenia were identified using univariate analysis of patient characteristics, disease type, and laboratory values immediately before the start of treatment. Variables with p<0.2 identified in the univariate analysis were used as independent variables in the multivariate analysis. This analysis identified "creatinine clearance (CCr) <60 mL/min" as a significant factor (odds ratio, 4.790; 95% confidence interval [CI], 1.380-16.70; p=0.014). Subsequently, time in days to the initial platelet transfusion after the initial administration of AZA was analyzed using the log-rank test. The overall median time in days to platelet transfusion was 370 days. The log-rank test was used to determine the influence of patient characteristics, disease type, and laboratory values immediately before the start of treatment. The subsequent Cox proportional hazard regression analysis using variables with p<0.2 as independent variables identified "hemoglobin (Hb) <8.0 g/dL" as a significant factor (hazard ratio, 2.143; 95% CI, 1.001-4.573; p=0.048). The results of this study led to the following clinical implications: first, patients with CCr of <60 mL/min at the start of treatment should be treated with caution due to the risk of thrombocytopenia. Second, patients with Hb of <8.0 g/dL at the start of treatment may require platelet transfusion in the early stage of treatment.

P–146 Differential impact of three embryo culture media for IVF on in vitro development and perinatal outcome: a single-center RCT

Study question

This report provides updated data from an RCT determining which embryo culture medium yields optimal IVF outcomes.

Summary answer

Embryo culture systems used for IVF differentially affected preimplantation development and resultant obstetric and perinatal outcomes, including birthweights of live-born singletons.

What is known already

Currently, multiple embryo culture medium systems are in use for IVF, raising questions regarding which is optimal. However, the ability of a medium to yield preimplantation embryos is not necessarily indicative of embryo viability. For example, supplementation of medium with serum was commonly used to increase animal blastocyst yields, but this impaired embryonic, fetal, and offspring health. In humans, medium composition and culture duration can influence IVF efficacy and offspring phenotype. Given the importance of culture systems in determining clinical outcomes, existing data regarding differential culture system impacts are insufficient and additional well-designed studies are required.

Study design, size, duration

Between February 2016 and August 2017, 795 couples undergoing their first autologous clinical IVF cycle and freeze-all strategy were recruited. Participants were randomized via computer-generated tables into three groups. Following standard oocyte retrieval and IVF/ICSI procedures, embryos were cultured using three different culture media, G1 Plus/G2 Plus (G1/G2; Vitrolife), Global Total (GT; LifeGlobal), or Sequential Cleav/Sequential Blast (SC/SB; Origio). Thirty-eight patients exhibiting no 2PN oocytes following insemination or those undergoing fresh embryo transfers were excluded.

Participants/materials, setting, methods

For patients yielding a single good-quality cleavage-stage (day–2 or day–3) embryo, that cleavage-stage embryo was vitrified. For patients yielding two or more good-quality cleavage-stage embryos, two or less good-quality cleavage-stage embryos were vitrified. The culture period of the remaining embryos was extended, and all good-quality blastocyst-stage (day–5 or day–6) embryos were vitrified. This report presents data for vitrified embryo transfer performed until the end of December 2020.

Main results and the role of chance

The mean per-cycle vitrified embryo yield (± SD) was comparable between groups for cleavage-stage embryos, but significantly different for blastocyst-stage embryos (G1/G2: 1.69 ± 2.2, GT: 2.53 ± 3.01, SC/SB: 2.04 ± 2.42; P = 0.001). Following vitrified cleavage- or blastocyst-stage embryo transfers, biochemical pregnancy rates were significantly different between groups (G1/G2: 55.6%, GT: 59.1%, SC/SB: 46.2%; P = 0.011). Furthermore, a between-group trend towards different live birth rates was observed (G1/G2: 41.7%, GT: 42.1%, SC/SB: 33.1%; P = 0.063). Of 382 live births, data for first-borns (n = 323; 295 singletons and 14 twin-pairs) are reported here. Perinatal data did not differ significantly between groups for both cleavage- and blastocyst-stage embryo transfers, including gestational age- and gender-adjusted singleton birthweight (z-score). Following multiple linear regression (including selected covariates), adjusted mean singleton birthweights were significantly lower in the G1/G2 and GT groups than in the SC/SB group (by 131 g; P = 0.011 and 110 g; P = 0.032, respectively) and tended to be lower for cleavage-stage embryo transfers than for blastocyst-stage embryo transfers (by 102 g; P = 0.053).

Limitations, reasons for caution

A larger cohort size and longer-term follow-up are required to verify and further elucidate the impact of embryo culture methods on child health. Such studies will raise awareness regarding the sensitivity of in vitro-cultured human embryos to their environment, ultimately resulting in practices that decrease IVF risks to offspring.

Wider implications of the findings: Pregnancy outcome of the medium yielding fewer blastocysts was comparable or superior to that of other media, highlighting the importance of differentiating between the ability to support preimplantation development versus the ability to yield viable embryos. Embryo culture medium had a greater impact than embryo transfer stage on live birthweight.

Trial registration number

UMIN000020910

P–221 Prospective randomized sibling study on gamete preparation, insemination and subsequent culture of human oocytes in a time-lapse system using media systems with and without antioxidants

Study question

Does the addition of antioxidants for gamete preparation, insemination and embryo culture lead to differences in embryo development and clinical outcome

Summary answer

Using an antioxidant-containing media system for sperm preparation, insemination and embryo culture imparts significantly higher good-quality blastocyst rates and improved clinical outcome in elderly patients.

What is known already

A previous study showed that adding combined antioxidants for sequential embryo culture in conventional incubators (interrupted culture) improves embryo viability and clinical outcome, especially for elderly patients. Here we investigated the combined effect of three antioxidants Acetyl-L-Carnitine (10 µM), N-Acetyl-L-Cysteine (10 µM), and α-Lipoic Acid (5 µM) during sperm preparation, insemination, and time-lapse culture in a single step medium on human embryo development and clinical outcome.

Study design, size, duration

Prospective randomized single center study including 143 couples for IVF/ICSI between August 2018 and December 2019. Inclusion required at least eight cumulus-oocyte-complexes (COCs) after retrieval. Cycles involving PGT, split IVF/ICSI, and surgically retrieved sperm were excluded. Immediately after retrieval oocytes were randomly distributed to a study or control media system with or without antioxidants (Vitrolife). Similarly, ejaculates were split and prepared with and without antioxidants.

Participants/materials, setting, methods

Sibling oocytes were inseminated in the respective group with accordingly prepared sperm. Single step embryo culture was conducted in medium with (Gx-TL) and without (G-TL) antioxidants in the EmbryoScope+. Embryo quality and clinical outcome were assessed in relation to maternal age (&lt;35/&gt;35 years). Good-quality embryos on day 3 were defined as 8- to 10-cells with even cells and low fragmentation; good-quality blastocysts as &gt; 3BB. Clinical outcome was assessed after single vitrified blastocyst transfer (SVBT).

Main results and the role of chance

From 143 participants (female age, 34.7±3.2 years), a total of 2424 COCs were collected; 1180 COCs/916 metaphase-II (MII) oocytes were allocated to Gx-TL media and 1244 COCs/981 MII oocytes to G-TL media. Age-related analysis in Gx-TL compared with G-TL in relation to allocated MII oocytes revealed a trend for higher fertilization rates in Gx-TL for both age groups (&lt;35: 72.1% vs. 66.9%; &gt;35: 70.7% vs. 64.9%, P &lt; 0.1). Good-quality day 3 embryo development/MII oocytes was higher, albeit not significant, in the elderly patients in Gx-TL (&lt;35: 35.9% vs. 34.4%; &gt;35: 31.1% vs. 27.9%). Overall day 5/6 blastocyst rate was similar for both media (&lt;35: 48.2% vs. 49.9%; &gt;35: 42.3% vs. 39.5%). Day 5/6 GQB rate was comparable for younger patients (&lt;35: 23.8% for Gx-TL vs. 26.0% for G-TL) but significantly higher in Gx-TL in elderly patients (&gt;35: 20.7% vs. 14.4%; P &lt; 0.05). A total of 200 SVBT were performed; 99 in the Gx-TL- and 101 in the G-TL-arm. We noted almost similar implantation and ongoing pregnancy rates between Gx-TL vs G-TL in the younger (&lt;35) age group (50.0% vs. 55.4%; 50.0% vs. 55.6%) but higher albeit not significant rates for Gx-TL in older (&gt;35) patients (44.1% vs. 33.3%; 44.1% vs. 33.3%).

Limitations, reasons for caution

In almost 95% of the cycles, oocytes were inseminated by ICSI; thus results may not equally apply for cycles with IVF. The use of a closed time-lapse system may have prevented from some environmental oxidative stress. Therefore results may come out different with a similar study using standard incubation.

Wider implications of the findings: Supplementation of antioxidants to media for gamete isolation and preparation, as well as subsequent single step time-lapse culture may improve GQE/B rates and clinical outcomes in certain age groups, plausibly through the reduction of oxidative stress. Further studies in selected sub-groups (severe OAT syndrome / testicular cases) may be indicated.

Trial registration number

UMIN000034482

Broadband sum frequency generation spectroscopy of dark exciton states in hBN-encapsulated monolayer WSe2

We demonstrate that broadband sum frequency generation (SFG) spectroscopy based on a partially incoherent supercontinuum light source can elucidate dark p-series excitons in monolayer WSe₂ encapsulated between hexagonal boron nitride (hBN) slabs. The observed 2p exciton peak energy is a few meV higher than that predicted by the Rytova-Keldysh potential model, which is originated from the Berry phase effect. Interestingly, although the radiative relaxation of the 2p exciton is weaker, the 2p exciton peak is broader than the 1s and 2s peaks, which indicates its faster dephasing than the 1s and 2s excitons. Measuring the excitation intensity and temperature dependence, we clarified that this broader linewidth is not caused by excitation- or phonon-induced dephasing, but rather by exciton-electron scattering.

Gefitinib induction followed by chemoradiotherapy in EGFR-mutant, locally advanced non-small-cell lung cancer: LOGIK0902/OLCSG0905 phase II study

Background

The role of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) induction coupled with standard concurrent chemoradiotherapy (CRT) is unclear in unresectable, stage III, EGFR-mutant non-small-cell lung cancer (NSCLC). Therefore, a phase II trial was conducted to evaluate the efficacy and safety of gefitinib induction followed by CRT in this disease setting.

Patients and methods

Patients with unresectable, EGFR-mutant, stage III NSCLC were administered gefitinib monotherapy (250 mg/day) for 8 weeks. Subsequently, patients without disease progression during induction therapy were administered cisplatin and docetaxel (40 mg/m² each) on days 1, 8, 29, and 36 with concurrent radiotherapy at a total dose of 60 Gy. The primary endpoint was the 2-year overall survival (OS) rate, which was hypothesized to reach 85%, with a threshold of the lower limit of 60%.

Results

Twenty patients (median age: 66 years; male/female: 9/11; histology: 20 adenocarcinoma; stage IIIA/IIIB: 9/11; and exon 19/21: 10/10) were enrolled. The 2-year OS rate was 90% (90% confidence interval: 71.4% to 96.8%), indicating that this trial met the primary objective. The overall response rate and 1- and 2-year progression-free survival rates were 85.0%, 58.1%, and 36.9%, respectively. Grade ≥3 adverse events (>10%) included hepatic toxicity during the induction phase and neutropenia and febrile neutropenia in the CRT phase. Radiation pneumonitis grade ≥3 or treatment-related death did not occur.

Conclusions

This is the first prospective study to demonstrate the favorable efficacy and safety of EGFR-TKI induction followed by standard CRT in EGFR-mutant, stage III NSCLC. Further confirmatory studies are needed.

•

This is the first prospective study evaluating gefitinib induction followed by CRT in EGFR-mutated, locally advanced NSCLC.

•

The 2-year OS rate was 90% (90% confidence interval: 71.4% to 96.8%), indicating that this trial met the primary objective.

•

The objective response rate throughout the treatment protocol was 85.0% (17 of 20).

•

The safety findings were consistent with the known safety profiles of all agents administered.

•

Our results might raise a critical point that needs to be evaluated in further studies to improve the cure rate.

Correction to: The acrid raphides in tuberous root of Pinellia ternata have lipophilic character and are specifically denatured by ginger extract

A correction to this paper has been published: https://doi.org/10.1007/s11418-021-01501-5

Absence of microsatellite instability in extramammary Paget's disease

Background

Deficiency of DNA mismatch repair (MMR) induces microsatellite instability (MSI). Pembrolizumab, an antibody targeting PD‐1 (an immune checkpoint inhibitor), is more effective against MMR‐deficient tumours than against MMR‐proficient tumours. The status of MMR is a useful biomarker for predicting the effectiveness of pembrolizumab administration. Although the status of MMR has attracted attention in skin tumours, there are few reports on MSI in extramammary Paget's disease (EMPD).

Objectives

To evaluate the status of MMR in patients with EMPD.

Materials & Methods

One hundred one patients with EMPD were included. MMR status of the genomic DNA of each subject was analysed using Promega panel (approved as a companion diagnostic agent for the administration of pembrolizumab).

Results

MSI testing showed the occurrence rates of MSI‐high (more than two markers are unstable), MSI‐low (one marker is unstable) and MSS (all markers are stable) tumour tissues were 0% (0/101), 1.0% (1/101) and 99.0% (100/101), respectively.

Conclusion

The status of MMR may not be useful for the potential therapeutic application of pembrolizumab.

Multifaceted array-based keloidal gene expression profiling reveals specific MDFI upregulation in keloid lesions

BACKGROUND

Keloid lesions are characterized by mesenchymal cell proliferation and excessive extracellular matrix deposition. Previous microarray analyses have been performed to investigate the mechanism of keloid development. However, the molecular pathology that contributes to keloid development remains obscure.

AIM

To explore the underlying essential molecules of keloids using microarrays.

METHODS

We performed microarray analyses of keloid and nonlesional skin tissues both in vivo and in vitro. Gene expression levels were compared between tissues and cells. Quantitative reverse transcription (qRT)-PCR and immunohistochemical staining were used to determine the expression levels of molecules of interest in keloid tissues.

RESULTS

Several common molecules were upregulated in both keloid tissues and keloid-lesional fibroblasts. PTPRD and NTM were upregulated both in vivo and in vitro. The genes MDFI and ITGA4 were located at the centre of the gene coexpression network analysis using keloid tissues. qRT-PCR revealed significant expression levels of PTPRD and MDFI in keloid tissues. Immunopathological staining revealed that MDFI-positive cells, which have fibroblast characteristics, were located in the keloid-associated lymphoid tissue (KALT) portion of the keloid tissue.

CONCLUSION

Our gene expression profiles of keloids could distinguish the difference between lesional tissue and cultured lesional fibroblasts, and MDFI was found to be commonly expressed in both tissues and cells. Thus, MDFI-positive cells, which were located in the KALT, may play an important role in keloid pathogenesis and thus might be useful for in vitro keloid studies.

W-band millimeter-wave back-scattering system for high wavenumber turbulence measurements in LHD

A 90 GHz W-band millimeter-wave back-scattering system is designed and installed for measuring electron scale turbulence (k_⊥ρ_s ∼ 40). A metal lens relay antenna is used for in-vessel beam focusing, and a beam diameter of less than 40 mm is achieved in the plasma core region. This antenna can be steered at an angle of 159° ± 6°, which almost covers the plasma radius. The estimated size of the scattering volume is ∼105 mm at the edge and 135 mm at the core, respectively. A 60 m corrugated waveguide is used to achieve a low transmission loss of ∼8 dB. A heterodyne detection system for millimeter-wave circuits with probing power modulation can distinguish the scattered signal from background noise.

Dynamical Collectivity and Nuclear Quantum Effects on the Intermolecular Stretching Mode of Liquid Water

This study investigated the broadband terahertz and low-frequency Raman spectroscopy of liquid water (H₂O, D₂O, and H₂¹⁸O) over 2 decades of frequency to address long-standing challenges regarding the interpretation of the intermolecular stretching mode at around 5 THz. We experimentally demonstrated that the intermolecular stretching mode of liquid water obtained via terahertz spectroscopy is significantly redshifted and broadened compared with that via Raman. This result was rationalized by the enhanced dynamical collectivity probed by terahertz spectroscopy, although both have a common origin in the kinetic motion. Their temperature and isotope dependences emphasize the significance of oscillation mass in determining the intermolecular stretching lineshape, while quantum effects cannot be overlooked in both terahertz and low-frequency Raman spectra.

Dynamical visualization of anisotropic electromagnetic re-emissions from a single metal micro-helix at THz frequencies

The capability for actual measurements—not just simulations—of the dynamical behavior of THz electromagnetic waves, including interactions with prevalent 3D objects, has become increasingly important not only for developments of various THz devices, but also for reliable evaluation of electromagnetic compatibility. We have obtained real-time visualizations of the spatial evolution of THz electromagnetic waves interacting with a single metal micro-helix. After the micro-helix is stimulated by a broadband pico-second pulse of THz electromagnetic waves, two types of anisotropic re-emissions can occur following overall inductive current oscillations in the micro-helix. They propagate in orthogonally crossed directions with different THz frequency spectra. This unique radiative feature can be very useful for the development of a smart antenna with broadband multiplexing/demultiplexing ability and directional adaptivity. In this way, we have demonstrated that our advanced measurement techniques can lead to the development of novel functional THz devices.

The utility of a novel approach to quantify dyssynchrony by multidetector computed tomography

Funding Acknowledgements

Type of funding sources: None.

Background

Quantification of left ventricular (LV) dyssynchrony is of great interest for resynchronization therapy (CRT). Recently, cardiac computed tomography (CCT) is feasible for evaluation of dyssynchrony. Our aim was to assess a novel simplified approach using CCT to quantify LV dyssynchrony.

Methods

We studied 346 consecutive patients with a wide range of QRS width and ejection fractions (EF). Electrocardiogram-gated contrast-enhanced 256-slice multidetector CT (Brilliance 256 iCT, Philips Medical Systems) was performed before CRT. After CCT scan, the LV endocardial boundaries from short-axis images reconstructed at 5% increments of cardiac cycle were automatically detected, and a time from R-wave to maximal wall motion was calculated for each of the 16 standardized segments for all slices using software "Myocardial Contraction Map" (Argus, Inc Ehime, Japan). The standard deviation of all segments modified by mean heart rate (%SD) was respectively calculated as the global parameter of dyssynchrony. LVEF was also measured using MDCT.

Results

%SD was feasible in all patients, respectably. %SD was significantly different between the different QRS duration groups; narrow QRS (&lt;120ms): 9 ± 5%, relatively wide QRS (120-150 ms): 11 ± 6%, and significantly wide QRS (&gt;150 ms): 14 ± 7% (p &lt;0.001). Moreover, there was significantly difference in %SD between the different morphology groups; normal: 9 ± 7%, Non-left bundle branch block (Non-LBBB): 10 ± 6%, LBBB: 17 ± 7% (p &lt;0.001).

Conclusion

This novel simplified approach by CCT can quantify dyssynchrony in different QRS duration and morphology groups. This method has promise for clinical applications to the evaluation of patients for CRT.

Abstract Figure.

A structured summary of a study protocol for a multi-center, randomized controlled trial (RCT) of COVID-19 prevention with Kampo medicines (Integrative Management in Japan for Epidemic Disease by prophylactic study: IMJEDI P1 study)

Objective

We aimed to test our hypothesis that traditional Japanese (Kampo) medicine, hochuekkito (Hochu-ekki-to: HET) has a preventive effect for the symptoms on COVID-19.

Trial design

The study is designed as a multi-center, interventional, parallel-group, randomized (1:1 ratio), investigator sponsored, two-arm study.

Participants

Six thousand participants will be recruited from healthy hospital workers in 7 Japanese University Hospitals.

Inclusion criteria:

1. Age from 20 to 75 years old at the time of registration

2. Asymptomatic and body temperature below 37°C at the time of registration

3. Capable of eating orally

Exclusion criteria:

1. Previous upper respiratory inflammation due to viral infection (including suspected COVID-19)

2. Taking immunosuppressants

3. Allergic to the Kampo medicines used in this study

4. History of hypokalaemia, severe hypertension, severe liver dysfunction, and interstitial pneumonia

5. Regularly taking other Kampo medicines

6. Pregnant or possibly pregnant

7. Participating in other research

8. Judged to be unsuitable for this study by the doctor in charge

Intervention and comparator

Kampo group: participants receive HET in 9 tablets 2 times per day for 8 weeks.

Control group: participants receive placebo in the same dosage as the Intervention group - 9 tablets 2 times per day for 8 weeks. Placebo tablets are identical in appearance and package to HET. Taste of placebo is different from that of HET.

The Ohsugi Pharmaceutical Co. Ltd, Osaka, Japan manufactured the placebo and HET.

Main outcomes

Primary outcome: Number of patients with a SARS-CoV-2 RNA by ploymerase chain reaction (PCR) positive result with at least one symptom (fever, cough, sputum, malaise, shortness of breath) during the 12-week study period (including the 4-week observation period after oral administration).

Secondary outcomes:

1. Period from infection to onset

2. Period from the appearance of symptoms to the disappearance of PCR positive

3. Number of days until the appearance or improvement of symptoms

4. Severe stage: presence of hospitalization

5. Shock stage: ICU management required for mechanical ventilation, shock vitals or failure of organ(s) other than lungs

Safety endpoints include numbness in the hands and/or feet, edema, skin rash or other allergic symptoms, and gastric discomfort.

Randomisation

Patients are randomized (1:1 ratio) to each group using minimization implemented with the Electric data capture system (DATATRAK Enterprise Cloud), with balancing of the arms with age range (under 50 years of age or not) and having a history of risk factors for COVID-19 (cardiovascular disease, hypertension, diabetes, respiratory diseases).

Blinding (masking)

Only participants will be randomized.

Numbers to be randomised (sample size)

The main research hypothesis of this study is that Kampo medicines significantly prevent the onset of COVID-19. It is assumed that the infection rate before the administration of the drug under consideration will be 0% and that the incidence of COVID-19 thereafter will be 2- 3%, of which 70%-80% will show symptoms of COVID-19. Assuming that the pharmaceutical effect of the drug will be effective in 50% of patients and that the incidence rates in the placebo and drug groups will be 1.4%-2.4% and 0.7%-1.2%, respectively, the placebo is calculated at 2%, and the study drug at 1%. Since the frequency of verification is low and the number of cases will be large, we set a total of 10 analyses (9 interim analyses and a final analysis). Since the number of cases at the time of the final analysis will be 4,986 under the conditions of α = 0.05 and a power of 80% by the Peto method. We set at 600 cases in each interim analysis with an estimated dropout rate of 16.9%. Finally, the total number of cases is set to 6,000 with 3,000 in the placebo group and 3,000 in the HET group.

Trial status

Protocol version 1.3 of October 23rd , 2020. Recruitment start (expected): December 1^st, 2020. Recruitment finish (expected): December 31^st, 2022.

Trial registration

This trial is registered in the Japan Registry of Clinical Trials (jRCT) (jRCTs031200150) on 14 October 2020.

Full protocol

The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest of expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-020-04939-2.