Efficacy measures

Biopharmaceutic studies (in vitro) Clinical study Drug release/dissolution Measurement of drug efficacy Measurement of the rate of drug dissolved under specified conditions 

Dr. Loden is a member of several national and international societies such as the International Society for Bioengineering and the Skin, and acts in the Committee of the European Group of Efficacy Measurements of Cosmetics and Other Topical Products (EEMCO) and the Scandinavian Society of Cosmetic Chemists (SCANCOS). She is also a member of the editorial board of the International Journal of Cosmetic Science. 

Rogier V, Balls M, Basketter D, et al. (1999) The Potential Use of Non-invasive Methods in the Safety Assessment of Cosmetic Products. The Report and Recommendations of ECVAM/EEMCO (The European Group for Efficacy Measurements on Cosmetics and Other Topical Products) Workshop 36. European Commission, Institute for Health and Consumer Protection, European Centre for Validation of Alternative Methods (ECVAM). 

Both issues are widely discussed by Rieger,4 who wrote that what is actually measured is pH of the (extractable) water-soluble constituents of skin. Due to that problem, Rieger proposed to call that measured value not pH of the skin but pH on the skin or the apparent pH. That issue is also raised and described by Parra and Paye in guidelines of European Group on Efficacy Measurement of Cosmetics and Other Topical Products (EEMCO).5 

Both the quantity and the types of data able to be collected will be affected by the nature of the clinical study patients may be inpatients or outpatients, and this in turn will govern the nature of pharmacoeconomic data that can be recorded. It is also important whether a clinical trial is intended as a pivotal trial for registration or not if a study is pivotal, then a clinical efficacy measure will have to be the primary end point. Pharmacoeconomic parameters can still be incorporated into such a study as secondary end points, and still provide valuable information. If, on the other hand, the clinical research addresses a health system delivery issue, then the pharmacoeconomic end points may well be primary, and the study design need not be constrained by FDA-mandated requirements for the double-blind, placebo-controlled aspects of proof of efficacy. 

Various forms of psychotherapy are regarded as effective interventions in mild to moderate depression, but studies comparing the economics of psychotherapy and pharmacotherapy are few (Rosenbaum and Hylan, 1999). One study found that the total health-care costs for patients who received psychotherapy were no different from those for patients who received an antidepressant. However, no efficacy measure was used (Edgell and Hylan, 1997). A randomized, prospective study which evaluated the treatment of depression with nortriptyline, interpersonal therapy or treatment as usual, with outcomes expressed in quality-adjusted life years, found that nortriptyline but not interpersonal therapy was a cost-effective alternative to treatment as usual (Lave et al, 1998). 

The phase III Frontal Hair Loss study was conducted in parallel with the phase III Pivotal studies in order to evaluate the efficacy of finasteride 1 mg primarily in the frontal scalp area (Leyden et al., 1999), as opposed to the vertex. The frontal hair loss study used end points similar to those used in the Pivotal studies and demonstrated significant improvements in all predefined efficacy measures with finasteride as compared with placebo. Treatment with finasteride significantly 

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