Abstract: A novel aseptic process for the preparation of intravenous and other pharmaceutical products, especially parenteral solution is provided as well as the pharmaceutical products produced thereby. The process involves ambient temperature mixing, filtering and filling in special enclosures, the surfaces of which have been rendered free of pathogenic organisms. The enclosures are further provided with sterile air by filtration through high efficiency particulate air filters. Positive pressure sterile air is caused to flow across the enclosure in a unidirectional, substantially lateral flow pattern in a generally diagonal direction, to effect a sweeping of sterile air in a continuous manner through the enclosure. Compounding of ingredients preferably is conducted in a separate enclosure from the filtration and filling processes. The apparatus is free of pathogenic organisms and includes a novel backflow pressure manifold system to control internal pressure exerted in the filtering and filling tubing.