The covered scientific area by Department of Pharmacokinetics is (1) pharmacokinetic principles of drugs after administered into the body, i.e. absorption, distribution, metabolism and excretion, are studied both in experimental animals and human volunteers, and (2) drug delivery system (DDS) based on the modification of the pharmacokinetic process, mainly the absorption process and distribution process. Through the tree decade's study, Prof. Takada innovated many DDSs. Among them, gastrointestinal mucoadhesive patch system (GI-MAPS) is a powerful system for the oral delivery of peptide/protein drugs. To accelerate the development of GI-MAPS, bioventure company, BioSerenTach Inc., was born in 2001. Dr. Shibata was working in our laboratory for one decade and performed a good scientific work on the pharmacokinetics of anti-AIDS drugs. He was raised to a full professor in 2005 at Doshisha Women's University. Thereafter, Dr. Sugioka joined to our department in 2005 and working on the pharmacokinetic of immunosuppressants. Now on-going projects in our department are as follows;

1. GI-MAPS
To solve the two problems of oral protein administration, hydrolytic degradation and poor membrane permeability, GI-MAPS was designed. By forming a high concentration gradient of protein between inside the system and enterocytes and prevent the attack of proteolytic enzymes by water-insoluble membrane, protein drugs like erythropoietin (EPO), G-CSF, insulin, interferon etc. can be orally available.

2. Microneedles as percutaneous DDS
Self-dissolving microneedles (SDMN) has been innovated by Prof. Takada in 2004 and now several application studies are under progress. With SDMN, insulin is percutaneously well absorbed with the bioavailability (BA) of over 93 %. SDMN containing EPO, insulin, interferon and low molecular weight heparin, is prepared in our laboratory and is administered to mice, rats and dogs. By measuring the serum or plasma drug level of pharmacological activity, SDMN is evaluated.

3. Pharmacokinetics of immunosuppressants
By the development of strong immunosuppressant, tacrolimus, liver transplantation is now accepted as a regular clinical treatment. However, the dosage regimen is very difficult because of its complicated pharmacokinetic characteristics, i.e. poor-solubility, poor absorbability and wide inter-subject variation. To solve, these problems, basic pharmacokinetic study is performed.

4. Pharmacokinetics of anti-AIDS drugs
Protease inhibitors, especially ritonavir, are metabolized by P450 3A. Through their metabolic process, drug interactions often occur with the concomitantly used drugs. To predict the clinical drug interaction from the preclinical stage experiment, we are developing new in vivo technologies.