Abstract: A dual-chamber type prefilled syringe comprises a cylindrical body within which a front plug member, a middle plug member and an end plug member are hermetically fitted to form a first chamber and a second chamber. The cylindrical body has an inner surface formed with a bypass. When the middle plug member moves to a position where the bypass is formed, the first chamber is communicated with the second chamber for the first time via the bypass. In this beginning state of liquid transfer (S), an inner volume (VS) of the cylindrical body between a leading end of the cylindrical body and a rear end of the front plug member is set to be at least 60% of a volume (VC) of a second component. When liquid component within the second chamber flows into the first chamber, it is possible to prevent part of the liquid component from passing through the first chamber to reach a portion for attaching an injection needle at a leading end of the cylindrical body.

Abstract: A dual-chamber type prefilled syringe comprises a cylindrical body within which a front plug member, a middle plug member and an end plug member are hermetically fitted to form a first chamber and a second chamber. The cylindrical body (2) has an inner surface formed with a bypass (14). When the middle plug member (7) moves to a position where the bypass (14) is formed, the first chamber (9) is communicated with the second chamber (10) for the first time via the bypass (14). In this beginning state of liquid transfer (S), an inner volume (VS) of the cylindrical body (2) between a leading end (2a) of the cylindrical body (2) and a rear end (6b) of the front plug member (6) is set to be at least 60% of a volume (VC) of a second component (12). When liquid component within the second chamber flows into the first chamber, it is possible to prevent part of the liquid component from passing through the first chamber to reach a portion for attaching an injection needle at a leading end of the cylindrical body.

Abstract: A novel microparticle preparation comprising microparticles of a polymer which contain a drug and are at least partially or wholly coated with a water-soluble inorganic salt, a water-soluble organic acid or a water-soluble salt of an organic acid, which acts as an agent for preventing aggregation of the microparticle preparation is disclosed. The preparation is produced by spraying a polymer solution containing a drug and a solution or dispersion of a water-soluble inorganic salt, a water-soluble organic acid or a water-soluble salt of an organic acid from different nozzles and contacting them with each other in a spray dryer. In this procedure, if desired, a non-ionic surfactant may be added to the solution of the water-soluble inorganic salt, the water-soluble organic acid or the water-soluble salt of organic acid, or a solution of non-ionic surfactant may be sprayed from the other nozzle simultaneously.