Demonstrating effectiveness or demonstrating not ineffectiveness – A potential solution for rare disease drug product development?

ABSTRACT

For review and approval of new drug products, substantial evidence regarding safety and effectiveness of the drug products under investigation are necessarily provided. A traditional approach is to test a null hypothesis of ineffectiveness against an alternative hypothesis of effectiveness at the 5% level of significance. The rejection of the null hypothesis of ineffectiveness is in favor of the alternative hypothesis of effectiveness. This approach, however, is somewhat misleading because the rejection of the null hypothesis of ineffectiveness leads to the conclusion of not ineffectiveness, which consists of the proportion of inconclusiveness and the proportion of effectiveness. In this article, we explore the potential use of the concept of demonstrating not ineffectiveness and then effectiveness for regulatory approval of new drug products, especially for rare disease drug products. For rare disease drug product development, one of the major obstacles and challenges is how to use small patient population available for achieving the same standards for regulatory approval. To address this problem, a two-stage approach by first demonstrating not ineffectiveness and then ruling out (or controlling) the probability of inconclusiveness for demonstrating effectiveness is proposed. The proposed two-stage approach is useful with small patient population available for achieving the same standards for regulatory approval of rare disease drug products.     

Comparison between a new multiplex electrochemiluminescence assay and the WHO reference enzyme-linked immunosorbent assay to measure serum antibodies against pneumococcal serotype-specific polysaccharides

Background

Two electrochemiluminescence (ECL) assays were developed which, together, can simultaneously measure serum antibodies against pneumococcal capsular polysaccharides (PnPS) for 17 serotypes. The assays were validated for the 13 PnPS included in the 13-valent pneumococcal conjugate vaccine (PCV13). As recommended by the World Health Organization (WHO), we compared the ECL assays with the WHO reference enzyme-linked immunosorbent assay (ELISA) and derived a threshold corresponding to the 0.35?µg/mL threshold established for the WHO reference ELISA for the non-inferiority comparison and licensure of new PCVs against invasive pneumococcal disease.

Prediction of human pharmacokinetics of typical compounds by a physiologically based method using chimeric mice with humanized liver

1. In this study, total body clearance (CL_t), volume of distribution at steady state (V_ss) and plasma concentration–time profiles in humans of model compounds were predicted using chimeric mice with humanized livers.

2. On the basis of assumption that unbound intrinsic clearance (CL_Uint) per liver weight in chimeric mice was equal to those in humans, CL_t were predicted by substituting human liver blood flow and liver weights in well-stirred model. V_ss were predicted by Rodgers equation using scaling factors of tissue-plasma concentration ratios (SF_Kp) in chimeric mice estimated from a difference between the observed and predicted V_ss. These physiological approaches showed high prediction accuracy for CL_t and V_ss values in humans.

3. We compared the predictability of CL_t and V_ss determined by the physiologically based predictive approach using chimeric mice with those from predictive methods reported by Pharmaceutical Research Manufacturers of America. The physiological approach using chimeric mice indicated the best prediction accuracy in each predictive method.

4. Simulation of human plasma concentration–time profiles were generally successful with physiologically based pharmacokinetic (PBPK) model incorporating CL_Uint and SF_Kp obtained from chimeric mice.

5. Combined application of chimeric mice and PBPK modeling is effective for prediction of human PK in various compounds.

     

Pharmacokinetics and distribution of schisandrol A and its major metabolites in rats

1.?Schizandrol A is an active component in schisandra, also the representative component for the identification of schisandra.

2.?A rapid resolution liquid chromatography coupled with quadruple–time–of–flight mass spectrometry (RRLC–QTOF/MS) was developed to investigate the pharmacokinetics of schizandrol A after its intragastric administration (50?mg/kg) in rats.

3.?Schizandrol A was rapidly absorbed (T _max = 2.07?h), with a longer duration (t _1/2 = 9.48?h) and larger apparent volume of distribution (Vz/F?=?111.81?l/kg) in rats. Schizandrol A can be detected in main organs and the order of its distribution was in the liver?>?kidney?>?heart?>?spleen?>?brain, particularly higher in the liver.

4.?Five schizandrol A metabolites were identified, including 2–demethyl–8(R)–hydroxyl–schizandrin, 3–demethyl–8(R)–hydroxyl–schizandrin, hydroxyl–schizandrin, demethoxy–schizandrin, 2, 3–demethyl–8(R)–hydroxyl–schizandrin, indicating that the hydroxylation and demethylation may be the major metabolic way of schizandrol A.

5.?This study defined the pharmacokinetic characteristics of schizandrol A in vivo, and the RRLC–QTOF/MS is more sensitive and less limited by conditions, and needs less samples, which may be a useful resource for the further research and development of schisandrol A.     

玳玳果黄酮降脂提取物体内组织分布规律及特征研究

目的：建立UPLC-MS/MS分析方法同时测定玳玳果黄酮降脂提取物效应组分新橙皮苷和柚皮苷在大鼠10种脏器组织中含量，分布规律及特征。方法：采用UPLC-MS/MS技术建立提取物效应组分新橙皮苷及柚皮苷在大鼠心、肝、脾、肺、肾、脑、胃、小肠、脂质、肌肉组织中的定量分析方法；大鼠给药后分别于0.33，0.67，1，4，8 h的5个时间点，分别摘取以上10种脏器组织，测定脏器组织及血液中效应组分的质量浓度，采用DAS（V 2.0）药动学软件对各样本的药物浓度-时间数据进行房室拟合，并计算不同组织效应组分的药-时曲线下面积（AUC）及平均滞留时间（MRT）。结果：所建立的UPLC-MS/MS定量分析方法具备良好的专属性、标准曲线及线性范围良好、方法准确度与精密度、定量下限均符合有关规定；玳玳果黄酮降脂提取物效应组分在血液中的分布符合一室模型，除肾脏及脑组织外，其余脏器中提取物效应组分的房室特征多为静脉注射的二室模型，柚皮苷在肾脏中的拟合结果为非静脉注射的二室模型，新橙皮苷在脑组织拟合结果为静脉注射的三室模型，给药后8 h各组织中效应组分新橙皮苷及柚皮苷AUC值大小顺序均为小肠 > 胃 > 肾 > 脂质 ≈ 脾脏 > 肺 > 肌肉 > 肝 > 心 > 脑，效应组分在各脏器中均无明显蓄积；效应组分在血液、肾脏、肝脏中的滞留时间较长，MRT均大于2 h，脂质最短，MRT不足1 h；各脏器中新橙皮苷的药-时曲线下面积约是柚皮苷的3倍，而心、肝、肾中则是3.5，2.1和3.4倍。结论：玳玳果黄酮降脂提取物效应组分在大鼠组织中分布迅速，达峰时间早于血液；效应组分在肠道内消除缓慢，给药8 h后在各脏器中的含量均显著下降且无特异的蓄积部位。研究结果揭示玳玳果黄酮降脂提取物效应组分在大鼠体内的分布特征及规律，为进一步理解玳玳果黄酮降脂提取物在体内的作用靶点及机制奠定了基础。     

Boosting treatment stabilization in patients of amphetamine-type stimulant use disorder

BackgroundTo investigate boosting effects on treatment stabilization in the mandatory treatment modality for patients of amphetamine-type stimulant use disorder.MethodsThis is a retrospective follow-up study over a period from January 2013 to December 2018. We analyzed 425 patients of amphetamine-type stimulant use disorder under mandating treatments. Treatment stabilization for a given patient was defined once 4 negative urinalysis had been observed. We developed a dynamic monitoring model of boosting effects informed by the available data, specifically the number of negative urine samples required to reach stabilization, the sum of urinalyses done at the time when the given number of negative urine samples had been observed and who the patient was. To represent the simulated population, a Monte Carlo method was used to generate p-values from 1000 experiments conducted on a computer.ResultsIn the observed samples, the probability of 4 negative results in urinalysis from 4 outpatient visits was 75.5%. In comparison, the probability for achieving 4th negative results in urinalysis over 4 visits from negative binominal distribution was 57.3%, and from the computer simulation, 49.8%. The observed samples had significantly higher probability of achieving 4 negative results in urinalysis over 4 outpatient visits (p < 0.001).ConclusionsThe mandatory treatment modality boosted treatment stabilization for patients of amphetamine-type stimulant use disorder. The major benefit of using the monitoring model is the ability to monitor boosting effects of stabilization. Results supported the effectiveness of this mandatory treatment modality and can be implemented in deferred-prosecution based treatment modality.     

Altered pharmacokinetics of combined oral contraceptives in obesity — multistudy assessment

Objective

The objective was to evaluate the pharmacokinetics (PKs) of levonorgestrel (LNG)-containing combined oral contraceptives (COCs) in obese women.

FBG、PCT及IL-10在开颅术后颅内感染患者中的表达及意义

目的探讨纤维蛋白原(Fibrinogen,FBG)、降钙素原(Procalcitonin,PCT)及白细胞介素-10(Interleukin-10,IL-10)在开颅术后颅内感染患者中的表达及意义。方法选取衡水市人民医院2018年1月-2019年3月收治的需行开颅手术治疗的患者200例作为研究对象,以是否发生颅内感染为标准分为感染组(n=56)及非感染组(n=144)。分析感染组患者病原菌分布,比较两组患者及不同病程感染患者FBG、IL-10及PCT水平。结果感染组患者手术时间、术后脑脊液漏的发生及引流管放置与对照组比较,差异均有统计学意义(P<0.05)。200例患者发生颅内感染且脑脊液细菌培养为阳性的病例56例,感染发生率为28.00%。56例感染患者脑脊液培养共分离病原菌64株,其中革兰阴性菌35株占54.69%,以铜绿假单胞菌为主,革兰阳性菌26株占40.63%,以金黄色葡萄球菌和表皮葡萄球菌为主,真菌3株占4.69%,均为假丝酵母菌。感染组患者血液以及脑脊液FBG、IL-10及PCT水平均高于非感染组(P<0.05)。56例感染患者34例病程<3 d,22例病程>3 d,随着病程延长,患者血液与脑脊液FBG、IL-10及PCT水平均升高(P<0.05)。结论开颅术后颅内感染病原菌分布以革兰阴性菌为主,患者FBG、IL-10及PCT水平均升高,且与病情进展密切相关,可作为开颅术后颅内感染诊断指标。     

Diagnostic and prognostic value of red blood cell distribution width in sepsis: A narrative review

Previous studies showed that red blood cell distribution width (RDW) can be used as a prognostic and diagnostic index in various non-hematological diseases, including severe infections and sepsis. Here, we provide a narrative review to summarize the findings of available studies investigating the relationship between RDW and sepsis. Current evidence suggests that increased RDW on admission, both in adults and neonates, may be associated with unfavorable outcomes on the short- and long-term. In patients with suspected sepsis, RDW has modest value for predicting positive blood culture. Accordingly, its diagnostic value for sepsis seems limited, whilts dynamic changes of RDW are associated with outcome of sepsis. Taken together, these results suggest that RDW could be used as a prognostic index in septic patients.     

2016至2018年某医院真菌血流感染者流行病学特征及耐药性分析

目的分析真菌性血流感染的病原菌分布以及耐药特征，为真菌血流感染的早期合理用药提供理论依据。 方法回顾性分析武汉大学人民医院2016年1月至2018年12月收治的真菌性血流感染者的菌群、科室分布以及耐药性。 结果入组192例真菌血流感染者的血培养样本中共分离192株真菌，其中白色念珠菌检出率为31.77%（61/192），其次热带念珠菌检出率为18.75%（36/192）；重症医学科检出率最高为33.85%（65/192）。所有菌株均对两性霉素B敏感，对其他抗菌药物耐药率分别为5-氟胞嘧啶4.49%（9/192）、伊曲康唑5.73%（11/192）、氟康唑10.94%（21/192）和伏立康唑11.46%（22/192）；除两性霉素B外，2016至2018年真菌对其他抗菌药物的耐药率均逐年上升，其中2018年所分离192株光滑念珠菌对伊曲康唑耐药菌率达46.7%。 结论真菌血流感染病原菌以念珠菌属为主，对目前抗真菌药物具有较高敏感性，但耐药率逐年上升，加强监测血培养病原菌变化及耐药趋势对指导临床用药至关重要。