Drug delivery metabolism

DOX, as EPI seems to form fewer amounts of ROS and secondary alcohol metabolite, (ii) encapsulation of anthracyclines in uncoated or pegylated liposomes that ensure a good drug delivery to the tumor but not to the heart, (iii) conjugation of anthracyclines with chemical moieties that are selectively recognized by the tumor cells, (iv) coadministration of dexrazoxane, an iron chelator that diminishes the disturbances of iron metabolism and free radical formation in the heart, and (v) administration of anthracyclines by slow infusion rather than 5-10 min bolus (Table 1). Pharmacological interventions with antioxidants have also been considered, but the available clinical studies do not attest to an efficacy of this strategy. 

Sustained- and controlled-release devices for drug delivery in the vaginal and uterine areas are most often for the delivery of contraceptive steroid hormones. The advantages in administration by this route—prolonged release, minimal systemic side effects, and an increase in bioavailability—allow for less total drug than with an oral dose. First-pass metabolism that inactivates many steroid hormones can be avoided [183,184],... 

LZ Benet, CY Wu, MF Hebert, VJ Wacher. Intestinal drug metabolism and antitransport processes A potential paradigm shift in oral drug delivery. J Controlled Release 39 139-143, 1996. 

As noted in the patent for this system, pulsatile systems are expected to have numerous applications in drug delivery, including site-specific delivery in the GI tract and bid (twice-a-day) dosing of two pulsatile systems that simulates qid (four times a day) dosing of immediately available products. The latter concept is expected to have a particular advantage for those drugs that have high first-pass metabolism. 

Structural specificity of mucosal-cell transport and metabolism of peptide drugs implication for oral peptide drug delivery. Pharm. Res. 1992, 9, 969-978. 

Benet LZ, Wu CY, Hebert MF and Wacher VJ (1996) Intestinal Drug Metabolism and Anti-Transport Processes A Potential Paradigm Shift in Oral Drug Delivery. 

Keywords Nasal drug delivery Preclinical drug development In situ Ex vivo, Drug metabolism Drug transport... 

Although this section deals mainly with the advantages of excised tissues with respect to nasal drug delivery studies, it is important to highlight some important attributes of nasal in situ perfusion model. Although this method does not provide data on systemic absorption, it enables study of the interactions of nasal mucosal enzymes, peptide substrates, and metabolic inhibitors and their implications for nasal drug absorption [13], It also enables the rate of nasal drug absorption to be determined. 

From a drug delivery perspective, the components of the host defence system comprise barriers that must be overcome to ensure efficient drug deposition as well as retention in and absorption from the respiratory tract. Important non-absorptive clearance mechanisms include mucociliary clearance, alveolar macrophages and metabolism (Figure 6.2). 

Keywords Pneumocytes Pulmonary drug delivery Pulmonary metabolism, Alveolar epithelium... 

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