Drug – bio-affecting and body treating compositions – Preparations characterized by special physical form – Implant or insert
Reexamination Certificate
2001-03-27
2003-02-25
Azpuru, Carlos (Department: 1615)
Drug, bio-affecting and body treating compositions
Preparations characterized by special physical form
Implant or insert
C424S430000, C514S772300
Reexamination Certificate
active
06524608
ABSTRACT:
BACKGROUND OF THE INVENTION
The invention is directed to a system for the controlled and sustained delivery of therapeutic agents to the human bladder.
There are numerous conditions of the bladder or urinary tract, such as cancer, inflammation, infection or incontinence, that may be treated by pharmaceutically active compounds. Many of these compounds are presently orally administered, however, that is a disadvantage in that systemic delivery is used to treat a condition or disease that is possibly more effectively treated by local applications. Also, many of the drugs used for the treatment of urge incontinence are anti-cholinergics with potent adverse side effects. An intravesical administration would accomplish a high concentration of the drug locally in the bladder wall or urine without producing a high serum concentration.
The following are some typical or currently used intravesical treatments of the bladder. For the treatment of bladder cancer, the drug doxorubicin is instilled directly into the bladder. A mycobacterium, Bacillus Calmette-Guerin, is also administered intravesically for treatment of carcinoma located in the bladder. For interstitial cystitis, DMSO is instilled intravesically to provide symptomatic relief. For incontinence, the anticholinergic drug oxybutynin chloride has been reported to have been used.
In these cases of intravesical delivery, the drug is simply instilled by solution into the bladder. A disadvantage with this approach is that for chronic conditions such as incontinence, the patient must be repeatedly catheterized, thus requiring frequent attention by trained medical staff. Also, the potential for infection is increased by repeated catheterization into the bladder, which can be as often as several times per day.
Okado et al., Yakugaku Zasshi, 105(10), 1001-1003 (1985); Nichihitsunyokaishi, 76(2), 197-203 (1985); tested an intravesical stick made of beeswax and surfactants, incorporating the drug bleomycin. However, it was observed that elution of the drug from the stick was rather rapid, about 1 to 3 days, and particles of the stick remain in the bladder, which could lead to blockage of the urinary tract or to the formation of kernels for bladder stones.
Accordingly, it would be desirable to provide a sustained or controlled delivery device that is capable of delivery of the drug for an extended period of time, preferably one week or longer, with the device biodegrading or bioeroding over time to clear the bladder.
SUMMARY OF THE INVENTION
The invention provides a bioerodible, sustained-release preparation for placement into the bladder through the urethra. The preparation may have a specific gravity less than or equal to that of the specific gravity range of human urine. The preparation comprises a pharmaceutically active ingredient and at least one bioerodible, pharmaceutically acceptable carrier, which is capable of sustaining delivery of the active ingredient within the bladder and is bioerodible and excretable without blockage of the urinary tract.
REFERENCES:
patent: 5021241 (1991-06-01), Yamahira et al.
patent: 5326761 (1994-07-01), Rozier
patent: 0 437 368 (1991-07-01), None
patent: 51-140582 (1976-12-01), None
patent: WO 917745 (1991-11-01), None
Ekstrom et al., “Intravesical Instillation of Drugs in Patients with Detrusor Hyperactivity,” Depts. Of Urology and Clinical Pharmacology, University Hospital, Lund, Sweden, 1992, pp. 11-67.
Massad et al., “The Pharmacokinetics of Intervesical and Oral Oxybutynin Chloride,”J. Urol., 1992, 148:595-597.
Okado et al., “Study of Intervesical Stick (Part 1): Method of Preparation and Dissolution Test for Active Component,”Yakugaku Zasshi, 1985, 105(10):1001-1003.
Okado et al., “Study of Intervesical Stick (Part 1): Development of Intervesical Stick, and Manufacture of Instillator,” Nichihitsunyokaishi, 1985, 76(2):197-203.
PCT Search Report, PCT/US98/06445, mailed Jul. 17, 1998.
Conston Stanley R.
Ottoboni Thomas B.
Yamamoto Ronald K.
Azpuru Carlos
Fish & Richardson P.C.
Point Biomedical Corporation
LandOfFree
Intravesical drug delivery system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Intravesical drug delivery system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Intravesical drug delivery system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3118105