Subcutaneous delivery system

Perez-Marrero R, Tyler RC. A subcutaneous delivery system for the extended release of leuprolide acetate for the treatment of prostate cancer. Expert Opin Pharmacother. 2004 5 447 157. 

Implants are a favored subcutaneous delivery system for veterinary formulation scientists as it affords long release of drug, and in contrast to its human counterparts, animals better tolerate the rather invasive administration procedures that are associated with implants. An example of a commercially available subcutaneous implanter is shown in Figure 12. 

Sartor, O. Dineen, M. K. Perez-Marreno, R. Chu, F. M. Catron, G. J. Tyler, R. C., An eight-month clinical study of LA-2575 30.0 mg a new 4-month, subcutaneous delivery system for leuprohde acetate in the treatment of prostate cancer. Urology, 2003, 62, 319-323. 

In this work we will focus on the use of the cubic phase as a delivery system for oligopeptides - Desmopressin, Lysine Vasopressin, Somatostatin and the Renin inhibitor H214/03. The amino acid sequences of these peptides are given in Table I. The work focuses on the cubic phase as a subcutaneous or intramuscular depot for extended release of peptide drugs, and as a vehicle for peptide uptake in the Gl-tract. Several examples of how the peptide drugs interact with this lipid-water system will be given in terms of phase behaviour, peptide self-diffusion, in vitro and in vivo release kinetics, and the ability of the cubic phase to protect peptides from enzymatic degradation in vitro. Part of this work has been described elsewhere (4-6). 

However, with respect to other delivery systems, microparticles could maintain their physicochemical characteristics unaltered for long periods, allowing long-term storage they can be administered through different ways (orally, intramuscularly, or subcutaneously), depending on their composition and they are suitable for industrial production [23,24],... 

Parenteral depot polymeric delivery system 7.5, 22.5, 30, 45 mg in a single-dose kit for subcutaneous injection Parenteral depot microspheres suspension 3.75, 7.5, 11.25, 15, 22.5, 30 mg in a single-dose kit for IM injection Lutropin [rLH] (Luveris)... 

A biodegradable delivery system using subcutaneous implants of fused pellets made from norethisterone and pure cholesterol has been tested (12). 

Of 335 patients with type 1 diabetes randomized to receive preprandial inhaled insulin as a dry powder formulation via an aerosol delivery system (Exubera) plus bedtime subcutaneous Ultralente insulin, or to continue NPH and regular insulins subcutaneously, 170 received inhaled insulin (mean age 33 years) (272). Six discontinued inhaled insulin, one because of mild cough, two because of hypoglycemia, and three because of insufficient responses. The risk of hypoglycemia was slightly lower in those who used inhaled insulin, at 8.6 events per month compared with 9.0 events per month in the conventional insulin group. 

Nondegradable subcutaneous implants as diffusion-controlled drug delivery systems, including Norplant, have been reviewed.89 99 Unlike biodegradable implants with long-term toxicological concern for metabolism of the polymer, nondegradable implants cannot avoid removal of the... 

Programmable implantable medication systems find use in the treatment of diabetes, conditions of chronic pain, and Parkinson s and Alzheimer s diseases. Infusions of morphine can be programmed to deliver the drug when the intensity of pain is high. This reduces the chance of the patient developing tolerance to the opioid. Daily injection of insulin subcutaneously causes pain and sometimes infection in diabetic patients. A delivery system that has high accuracy of pumping... 

Fig. 17 Syncro-Mate-C implant, a subdermal implant fabricated from the microreservoir dissolution-controlled drug-delivery system, and subcutaneous controlled release of nor-gestomet, a potent synthetic progestin, at constant rate for 20 days. The open ends on the implant do not affect the zero-order in vivo drug release profile. (Adapted from Ref. . )...

Fig. 19 (A) Cross-sectional view of the Alzet osmotic pump, an osmotic pressure-activated drug-delivery system. (B) The effect of 7 days of subcutaneous delivery of antidiuretic hormone (vasopressin) on the daily volume of urinary excretion and urine osmolality in the Brattleboro rats with diabetes insipidus.

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