Clinical trials pharmacokinetics applications

Even on a relatively small subset of reused data, it is possible to license old medicines for new therapeutic applications and greatly reduce the costs of clinical development—many of these reused medicines have already passed muster for pharmacokinetic safety, so smaller-scale clinical trials are possible, saving considerable money (e.g., Arakis—soon to become Sosei). Even Sildenafil may have new indications [39]. There are huge potential reserves of information to mine in each and every large pharmaceutical company ... 

In view of the regulatory delay that was caused by the need to apply for a CTC, a Statutory Order (SI 1974/498) was made during 1974, to provide an exemption from the need to hold a CTC in such cases, subject to certain conditions. This order applied to trials conducted by doctors and dentists on their own responsibility (DDX). The basis of the clinical trial exemption (CTX) scheme, introduced in 1981, to include studies initiated by the pharmaceutical industry, was that together with a detailed clinical trial protocol and summaries of chemical, pharmaceutical, pharmacological, pharmacokinetic, toxicological and human volunteer studies, a clinical trial in patients may proceed without the need for the additional details normally required for a CTC or Product Licence application. This exemption scheme was based on the requirements that ... 

A placebo-controlled, randomized clinical trial with monitoring of hypericin and pseudohypericin plasma concentrations was performed to evaluate the increase in dermal photosensitivity in humans after application of high doses of SJW extract (Table 2) (73). The study was divided into a single-dose and a multiple-dose part. In the single dose crossover study, each of the 13 volunteers received either placebo or 900, 1800, or 3600 mg of the SJW extract LI 160. Maximum total hypericin plasma concentrations were observed about four hours after dosage and were 0, 28, 61, and 159ng/mL, respectively. Pharmacokinetic parameters had a dose relationship that appeared to follow linear kinetics (73). 

Provide the quantitative composition and lot number of each finished dosage form used in each clinical trial, bioavailability and pharmacokinetic study, clinical pharmacology study, and dose tolerance study conducted during the investigational phases of the drug product. Cross-reference each formulation to the study report in the application and explain any differences in formulation. 

This entry will first survey the reasons for developing blood substitutes and outline the principles of oxygen delivery by PFC emulsions. It will then focus on the main challenges encountered in the development of such emulsions, namely the selection of an appropriate excretable PFC and the preparation of a stable, biocompatible emulsion. It will also allude to questions related to raw material procurement, product manufacture, and cost. Further sections will concern the pharmacokinetics, efficacy, and side effects of these oxygen carriers. Finally, the potential applications of these products will be outlined, including the status of their clinical trials, and some forward looking comments will be made. 

Chabaud, S. Girard, P. Nony, P. Boissel, J.P. Clinical trial simulation using therapeutic effect modeling application to ivabradine efficacy in patients with angina pectoris. J. Pharmacokinet. Pharmacodyn. 2002, 29 (4), 339-363. Minto, C.F. Schnider, T.W. Shafer, S.L. Pharmacokinetic and pharmacodynamics of remifentail. II. Model application. Anesthesiology 1997, 86 (1), 24-33. 

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