Search

The absence of a unanimous, industry-specific definition of quality is, to a certain degree, impeding the progress of ongoing efforts to "modernize" the pharmaceutical industry. This work was predicated on requests by Dr. Woodcock (FDA) to re-define pharmaceutical quality in terms of risk by linking production characteristics to clinical attributes. A risk simulation platform that integrates population statistics, drug delivery system characteristics, dosing guidelines, patient compliance estimates, production metrics, and pharmacokinetic, pharmacodynamic, and in vitro-in vivo correlation models to investigate the impact of manufacturing variability on clinical performance of a model extended-release theophylline solid oral dosage system was developed. Manufacturing was characterized by inter- and intra-batch content uniformity and dissolution variability metrics, while clinical performance was described by a probabilistic pharmacodynamic model that expressed the probability of inefficacy and toxicity as a function of plasma concentrations. Least-squares regression revealed that both patient compliance variables, percent of doses taken and dosing time variability, significantly impacted efficacy and toxicity. Additionally, intra-batch content uniformity variability elicited a significant change in risk scores for the two adverse events and, therefore, was identified as a critical quality attribute. The proposed methodology demonstrates that pharmaceutical quality can be recast to explicitly reflect clinical performance., (© 2010 Wiley-Liss, Inc. and the American Pharmacists Association)

The beta(2) adrenoreceptor is a large molecule of some 413 amino acids. The duration of stimulation of this receptor depends on where and for how long a beta(2) adrenergic drug attaches itself to the beta(2) adrenoreceptor. beta(2) adrenergic drugs have been used for over 5,000 years, but only recently have we had the advantage of adrenergic drugs specific to the beta(2) adrenoreceptor. The short-acting beta(2) adrenergic drugs most frequently used include albuterol, pirbuterol, and levalbuterol. Levalbuterol, the R enantiomer of albuterol, has been described by some as a more effective bronchodilator than racemic albuterol, because it contains none of the S enantiomer. Some contend that the S isomer has pro-inflammatory properties. The 2 long-acting beta(2) adrenergic drugs are salmeterol and formoterol. These drugs have a duration of 12 h and reportedly improve forced expiratory volume in the first second, quality of life, and symptoms. Some recent reports indicate that these drugs are associated with higher mortality, but several authors have registered the opinion that it is not the bronchodilator that should be questioned, but instead that the fault lies in the patient recruitment in those studies. Regardless, if these long-acting drugs are effective for a given patient, it would seem inadvisable to withdraw them, given the current state of evidence. Arformoterol tartrate, the R enantiomer of formoterol, was approved by the U.S. Food and Drug Administration in October 2006; it is available as a nebulizer solution, to be administered every 12 h. Several other long-acting R isomers and RR isomers are in the approval pipeline.

In the treatment of asthma, the conventional measures used to monitor a patient's progress and health status do not address the impact of functional impairments associated with the disease that may affect the patient's daily life. Unlike those measures, health-related quality of life (HRQL) reflects the physical, psychological, and social difficulties a patient perceives on a day-to-day basis. This study was conducted to determine the effects of once-daily budesonide inhalation powder via the Pulmicort Turbuhaler on the HRQL in adult patients with asthma previously treated with other inhaled corticosteroids. A total of 184 patients 18 to 70 years of age who previously received inhaled corticosteroids were enrolled in this double-blind, placebo-controlled, parallel-group, multicenter study. Patients were randomly assigned to budesonide 400 microg once daily or to placebo for 12 weeks. Each patient's HRQL was assessed at randomization and at weeks 4 and 12 with the Asthma Quality of Life Questionnaire (AQLQ). More patients receiving budesonide than those receiving placebo reported statistically significant (P < or = .05) improvements in HRQL at weeks 4 and 12. With the exception of the domain pertaining to exposure to environmental stimuli, differences from placebo in overall AQLQ scores and individual domain scores were clinically important (> or = 0.5 units). In addition, 2.4 patients needed to be treated with once-daily budesonide for 1 patient to demonstrate clinically important improvement. Budesonide 400 microg administered once daily via the Pulmicort Turbuhaler provides statistically significant and clinically important HRQL benefit in adult patients with asthma previously receiving inhaled corticosteroids.