Controlled local delivery of chemotherapeutic agents for treatin

Drug – bio-affecting and body treating compositions – Preparations characterized by special physical form – Matrices

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

424422, 424426, A61K 914

Patent

active

058465650

DESCRIPTION:

BRIEF SUMMARY
BACKGROUND OF THE INVENTION

This application is a 371 of US/PCT95/09805, filed Aug. 02, 1995.
This invention is in the field of localized delivery of chemotherapeutic agents to solid tumors.
One-third of all individuals in the United States alone will develop cancer. Although the five-year survival rate has risen dramatically to nearly fifty percent as a result of progress in early diagnosis and the therapy, cancer still remains second only to cardiac disease as a cause of death in the United States. Twenty percent of Americans die from cancer, half due to lung, breast, and colon-rectal cancer.
Designing effective treatments for patients with cancer has represented a major challenge. The current regimen of surgical resection, external beam radiation therapy, and/or systemic chemotherapy has been partially successful in some kinds of malignancies, but has not produced satisfactory results in others. In some malignancies, such as brain malignancies, this regimen produces a median survival of less than one year. For example, 90% of resected malignant gliomas recur within two centimeters of the original tumor site within one year.
Though effective in some kinds of cancers, the use of systemic chemotherapy has had minor success in the treatment of cancer of the colon-rectum, esophagus, liver, pancreas, and kidney and melanoma. A major problem with systemic chemotherapy for the treatment of these types of cancer is that the systemic doses required to achieve control of tumor growth frequently result in unacceptable systemic toxicity. Efforts to improve delivery of chemotherapeutic agents to the tumor site have resulted in advances in organ-directed chemotherapy, as by continuous systemic infusion, for example. However, continuous infusions of anticancer drugs generally have not shown a clear benefit over pulse or short-term infusions. Implantable elastomer access ports with self-sealing silicone diaphragms have also been tried for continuous infusion, but extravasation remains a problem. Portable infusion pumps are now available as delivery devices and are being evaluated for efficacy. (See Harrison's Principles of Internal Medicine 431-446, E. Braunwald et al., ed., McGraw-Hill Book Co. (1987) for a general review).
In the brain, the design and development of effective anti-tumor agents for treatment of patients with malignant neoplasms of the central nervous system have been influenced by two major factors: 1) the blood-brain barrier provides an anatomic obstruction, limiting access of drugs to these tumors; and 2) the drugs given at high systemic levels are generally cytotoxic. Efforts to improve drug delivery to the tumor bed in the brain have included transient osmotic disruption of the blood brain barrier, cerebrospinal fluid perfusion, and-direct infusion into a brain tumor using catheters. Each technique has had significant limitations. Disruption of the blood brain barrier increased the uptake of hydrophilic substances into normal brain, but did not significantly increase substance transfer into the tumor. Only small fractions of agents administered into the cerebrospinal fluid actually penetrated into the brain parenchyma. Drugs that have been used to treat tumors by infusion have been inadequate, did not diffuse an adequate distance from the site of infusion, or could not be maintained at sufficient concentration to allow a sustained diffusion gradient. The use of catheters has been complicated by high rates of infection, obstruction, and malfunction due to clogging. See T. Tomita, "Interstitial chemotherapy for brain tumors: review" J. Neuro-Oncology 10:57-74 (1991).
Controlled release biocompatible polymers for local drug delivery have been utilized for contraception, insulin therapy, glaucoma treatment, asthma therapy, prevention of dental caries, and certain types of cancer chemotherapy. (Langer, R., and D. Wise, eds, Medical Applications of Controlled Release, Vol. I and II, Boca Raton, CRC Press (1986)) Brain tumors have been particularly refractory to chemotherapy. One of the chief reasons is

REFERENCES:
patent: 4757128 (1988-07-01), Domb
patent: 4789724 (1988-12-01), Domb
patent: 4857311 (1989-08-01), Domb
patent: 4867978 (1989-09-01), Gold
patent: 4888176 (1989-12-01), Langer
patent: 4943579 (1990-07-01), Vishnuvajjala
patent: 5064823 (1991-11-01), Lee
patent: 5145684 (1992-09-01), Liversedge
patent: 5225404 (1993-07-01), Giovannella
patent: 5362831 (1994-11-01), Mongelli
patent: 5380751 (1995-01-01), Chen
patent: 5395850 (1995-03-01), Roth

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Controlled local delivery of chemotherapeutic agents for treatin does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Controlled local delivery of chemotherapeutic agents for treatin, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Controlled local delivery of chemotherapeutic agents for treatin will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-174756

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.