A system for multiphasic delivery of at least one growth factor at a treatment site comprises a delivery vehicle for releasing at least one growth factor in an initial release profile and a carrier for releasing at least one growth factor in a sustained release profile. The initial release profile releases at least one growth factor over a period of hours to days, wherein the growth factor is released in a large amount initially, with the remainder being released in progressively lower amounts. The sustained release profile releases at least one growth factor over a period of days to weeks, wherein the growth factor is released at a generally constant amount over such period. The system of the invention is particularly suited for applications on bioimplants. The invention also comprises methods and kits for multiphasic delivery of at least one growth factor. The invention also comprises calcium sulphate as a carrier for releasing at least one growth factor in both single and multiphasic systems for delivering at least one growth factor at a treatment site.