[Determination of the anti-infective action of an immunomodulator. Biostim as an example].

In order to evaluate the antiinfectious action of an immunomodulator, either in vitro or in vivo, in both animal and man, we have to answer three questions: What the targets are? Which models best allow the study of the mode of action? Which method should be used to evaluate clinical improvement? The targets of RU 41740 (Biostim), a purified Immunomodulator of biological origin, are the pool of immunocompetent cells with an enhancement of two major mediators: IL1 and CSF. As there are numerous interactions between antiinfectious, antiinflammatory, antiallergic responses and mediators pleiotropism, no reliable predictions exist. Moreover concerning the "in vivo" activity experimentally induced infections represent a preferential pharmacologic model in order to study the antiinfectious activity of an immunomodulating compound. Under such conditions, RU 41740 testing administered either orally, intraperitoneally or by aerosol is effective, whatever the responsible infectious agents are: extra or intracellular development bacteria, virus or yeasts. In regard to the differences of the local defenses (pulmonary and cutaneous), the targeted organ has to be identified during the mode of action studies. RU 41740 enhances alveolar macrophage metabolic functions in the respiratory tract. From a pharmacoclinical point of view, this stimulation of immune components has been investigated under different doses and treatment schedule of RU 41740 with a double blind versus placebo studies. The targeted pathology involves the risk of infections and immune deficiency. In chronic bronchitis infections often occur and are responsible for acute respiratory failures and this contributes to the obstructive syndrome. The clinical efficiency on prophylaxis must be evaluated by double blind versus placebo, randomized studies with a long follow-up period.(ABSTRACT TRUNCATED AT 250 WORDS)