Driving Efficiency: Leveraging Model-Informed Approaches in 505(b)(2) Regulatory Actions.

Introduced by the Hatch-Waxman Amendments of 1984, 505(b)(2) applications permit the US Food and Drug Administration to rely, for approval of a new drug application, on information from studies not conducted by or for the applicant and for which the applicant has not obtained a right of reference. This pathway is designed to circumvent the unnecessary duplication of studies already conducted on a previously approved drug. It can lead to a considerably more efficient and expedited route to approval compared to a traditional development path.

The quest for balance between capturing data and model complexity: A quantitative clinical pharmacology approach applied to monoclonal antibodies.

The main objective of this tutorial is to provide the readers with a roadmap of how to establish increasingly complex target-mediated drug disposition (TMDD) models for monoclonal antibodies. To this end, we built mathematical models, each with a detailed visualization, starting from the basic TMDD model by Mager and Jusko to the well-established, physiologically based model by Li et al. in a step-wise fashion to highlight the relative importance of key physiological processes that impact mAb kinetics and system dynamics.

Evaluating the Clinical Impact of Formulation Variability: A Metoprolol Extended-Release Case Study.

The objective of this research was to evaluate the impact of changes in the formulation of metoprolol extended-release (ER) tablets on dissolution, pharmacokinetic, and exercise-induced heart rate (EIHR) using a combined physiologically based absorption pharmacokinetic, and population pharmacokinetic/pharmacodynamic modeling and simulation approach. Using a previously developed physiologically based absorption pharmacokinetic model in DDDPlus and GastroPlus, we simulated the changes in drug release and exposure as the result of quantitative changes in the release-controlling excipient, hydroxylpropylmethylcellulose, for 50 and 200 mg. The similarity of dissolution profiles was assessed using the f test, and bioequivalence was tested on the simulated pharmacokinetic profiles.

Model-Based Approach to Predict Adherence to Protocol During Antiobesity Trials.

Development of antiobesity drugs is continuously challenged by high dropout rates during clinical trials. The objective was to develop a population pharmacodynamic model that describes the temporal changes in body weight, considering disease progression, lifestyle intervention, and drug effects. Markov modeling (MM) was applied for quantification and characterization of responder and nonresponder as key drivers of dropout rates, to ultimately support the clinical trial simulations and the outcome in terms of trial adherence.

Comparative study of genotypes of Mycobacterium tuberculosis from a Northern Indian setting with strains reported from other parts of India and neighboring countries.

This study was carried out to characterize Mycobacterium tuberculosis population in Ghatampur, Kanpur, North India, by spoligotyping and Mycobacterial Interspersed Repetitive Units-Variable Number of Tandem Repeats (MIRU-VNTRs) typing. A total of 335 isolates were genotyped by spoligotyping and Central Asian (CAS) sub-lineage was the most prevalent, comprising 59.1% of all isolates.

Genetic diversity & drug sensitivity profiles of isolates from two slums of Jaipur city, Rajasthan, India.

Background & Objectives: Slums are considered as hotspots of tuberculosis (TB). The study of genetic diversity and drug susceptibility profile of Mycobacterium tuberculosis (MTB) will help understand the transmission dynamics and can be used for better prevention and control of the disease. The aim of this study was to determine the drug susceptibility profiles and genetic diversity using the random amplified polymorphic DNA (RAPD) and mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU VNTR) of MTB isolates from sputum samples of pulmonary TB patients residing in the two slums of Jaipur city in Rajasthan, India.

Population Pharmacokinetics of Fixed Dose Combination of Ceftriaxone and Sulbactam in Healthy and Infected Subjects.

Increased antibacterial resistance (ABR) and limited drug discovery warrant optimized use of available antibiotics. One option is to rationally combine two antibiotics (fixed dose combination (FDC)) that may delay or prevent emergence of ABR in notorious pathogen. Major concern with FDC is the mutual interaction of its components that might influence their pharmacokinetic (PK) profile, requiring reassessing of whole formulation (adding cost and time).

Solid-state interactions at the core-coat interface: physicochemical characterization of enteric-coated omeprazole pellets without a protective sub-coat.

Conventionally, scanning electron or transmission microscopy, Raman and near infrared (NIR) spectroscopy, terahertz, florescence, and nuclear magnetic resonance imaging have been used to characterize functional coating structure. This study highlights the use of fluorescence microscopy to investigate the physicochemical stability and coating integrity of the commercially available enteric-coated omeprazole pellets containing a basic excipient and prepared by extrusion and spheronization or drug layering on the nonpareil seed, immediately followed by enteric coating (i.e.

Modulation of pyridinium cationic lipid-DNA complex properties by pyridinium gemini surfactants and its impact on lipoplex transfection properties.

The study presents the effects of blending a cationic gemini surfactant into cationic lipid bilayers and its impact on the plasmid DNA compaction and delivery process. Using nanoDSC, dynamic light scattering, zeta potential, and electrophoretic mobility measurements, together with transfection (2D- and 3D-) and viability assays, we identified the main physicochemical parameters of the lipid bilayers, liposomes, and lipoplexes that are affected by the gemini surfactant addition. We also correlated the cationic bilayer composition with the dynamics of the DNA compaction process and with transfection efficiency, cytotoxicity, and the internalization mechanism of the resultant nucleic acid complexes.

Prevalence of Mycobacterium tuberculosis with multiple copies of IS6110 elements in Gulbarga, South India.

This study was carried out to ascertain the prevalence of Mycobacterium tuberculosis by insertion sequence 6110 (IS6110) based DNA fingerprinting method in Gulbarga district belonging to the southern part of India. Results showed that among the 52 M. tuberculosis isolates studied, 57.

Interfacial engineering of pyridinium gemini surfactants for the generation of synthetic transfection systems.

Pyridinium gemini surfactants possess a soft charge, a high charge/mass ratio and a high molecular flexibility - all key parameters that recommend their use in synthetic gene delivery systems with in vitro and in vivo efficiency. In present study we generated a DNA delivery system through interfacial engineering of pyridinium gemini surfactants at the level of linker, hydrophobic chains and counterions. The self-assembling of the pyridinium amphiphiles and the physicochemical properties of the resultant supra-molecular assemblies were studied in bulk and in solution through a combination of techniques that included DSC, X-ray diffraction, polarized microscopy, CMC, dynamic light scattering and zeta potential measurements.

Heterocyclic cationic gemini surfactants: a comparative overview of their synthesis, self-assembling, physicochemical, and biological properties.

Gemini surfactants (GS) are presently receiving substantial attention due to their special self-assembling properties and unique interfacial activity. This comprehensive review is focused on positively charged heterocyclic GS, presenting their major synthetic access routes and examining the impact of structural elements on physicochemical and aggregation properties of this class of amphiphiles. Interaction of geminis surfactants with cells and their biological properties as novel transfection agents are emphasized through a detailed structure-activity relationship analysis.

Microarray analysis of efflux pump genes in multidrug-resistant Mycobacterium tuberculosis during stress induced by common anti-tuberculous drugs.

Treatment of multidrug-resistant tuberculosis has become one of the major problems in public health. Understanding the molecular mechanisms of drug resistance has been central to tuberculosis research in recent times. DNA microarray technology provides the platform to study the genomic variations related to these mechanisms on a comprehensive level.

Predominance of three copies of tandem repeats in rpoT gene of Mycobacterium leprae from Northern India.

This study has been carried out to get understanding of the origin among the strains of Mycobacterium leprae in patients from Northern India by using number of tandem repeats in rpoT gene as marker. Biopsies were collected from hundred leprosy cases (paucibacillary (PB) as well as multibacillary (MB)) across the spectrum from patients attending clinic at JALMA or diagnosed in Field Unit at Ghatampur (Kanpur). These biopsies were homogenized and DNA was extracted by a physiochemical procedure.

An indigenous approach to manage the osteoarthritis of knee joint with lakshadi guggulu, kalka-patra bandhan and knee traction.

The clinical study was attempted to develop a holistic treatment module for the patients of osteoarthritis of the knee. The study was done in 10 patients of Osteoarthritis of knee. The patients were given Lakshadi Guggulu Tablet, Kalka patra -bandhan ( Bandage of medicinal paste) and Knee joint traction.

In situ hybridization in the histological diagnosis of early and clinically suspect leprosy.

The present study tests the utility of the in situ hybridization procedure for M. leprae rRNA in the histological diagnosis of early leprosy and clinically suspect leprosy, both diagnostically demanding situations. The histological confirmation obtained with routine histopathology (Haematoxylin-Eosin staining for studying morphologic alterations and Fite-Faraco staining for demonstration of acid-fast bacilli) were 32% for early leprosy and 25% for clinically suspect leprosy.

10-12 years follow-up of highly bacillated BL/LL leprosy patients on combined chemotherapy and immunotherapy.

This study reports the follow-up results of 36 highly bacillated untreated BL/LL cases who were serially allocated to three treatment groups. Group I patients received a modified WHO regimen (Rifampicin 600 mg once a month supervised, 50 mg of Clofazimine and 100 mg of Dapsone daily unsupervised) and BCG 0.1 mg per dose 6 monthly; group II patients received the same multi-drug treatment (MDT) and Mw (2 x 10(8) killed bacilli per dose) 6 monthly: group III patients received the same MDT with 0.