Administration by Injection or Infusion

Due to the lack of activity after oral administration for most peptides and proteins, administration by injection or infusion - that is, by intravenous (IV), subcutaneous (SC), or intramuscular (IM) administration - is frequently the preferred route of delivery for these drug products. In addition, other non-oral administration pathways have been utilized, including nasal, buccal, rectal, vaginal, transder-mal, ocular, or pulmonary drug delivery. Some of these delivery pathways will be discussed in the following sections in the order of the increasing biopharmaceutic challenges to obtain adequate systemic exposure. 

Generic name/ Trade name Class Manufacturer Route Bioavailability Clearance3 Volume of distributionb) Half-life 

Abareli x/Plenaxis LHRH antagonist Praecis IM 208 48 L/day 4040 1607L 13.2 3.2 days 

Epoetin-a/ Epogen, Procrit Anti-anemic Amgen, Ortho IV, SC 4-13 h (IV) 16.3 3.0 h (SC) 

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