Selecting the optimal dose of low-molecular-weight hydroxyethyl starch (Pentastarch) for granulocyte collection.

A new, rapidly excreted, low-molecular-weight form of hydroxyethyl starch (Pentastarch), is effective and safe in centrifugation leukapheresis. To define the optimal dose of Pentastarch, 12 subjects donated granulocytes by continuous-flow, centrifugation leukapheresis on three occasions at 3-week intervals. Each subject received approximately 250,500, or 1000 ml of Pentastarch according to a random sequence during procedures in which 81 of donor blood was consistently processed. Plasma Pentastarch concentrations (mean mg/ml) measured immediately after leukapheresis were 3.1, 6.7, and 12.7 for the 250, 500-, and 1000-ml doses, respectively. Total leukocyte and neutrophil yields with the 500- or the 1000-ml doses of Pentastarch were similar, and both were significantly greater (p less than 0.05) than those with the 250-ml dose. Neutrophil yields per concentrate (mean X 10(-10) were 0.74, 1.72, and 1.73 for the 250-, 500-, and 1000-ml doses, respectively. Pentastarch dose had little effect on lymphocyte and platelet yields. No serious adverse effects were evident for any dose of Pentastarch during 12 weeks of observation. In particular, the 1000-ml dose did not produce increased toxicity. Thus, a single 500-ml bottle of 10 percent Pentastarch produced maximal yields; efficacy was not improved by doubling the dose.