Free Content

Biodegradable implants from poly-(alpha-hydroxy acid) polymers for isoniazid delivery

Authors: Hurley, L.; Andersen, B. R.

Source: The International Journal of Tuberculosis and Lung Disease, Volume 3, Number 11, November 1999 , pp. 1015-1024(10)

Publisher: International Union Against Tuberculosis and Lung Disease

Buy & download fulltext article:

Free content The full text is free.

View now:
PDF 1,180kb 


SETTING: In vitro and in vivo study of an isoniazid (INH) drug delivery system.

OBJECTIVE: To develop a system for the treatment of tuberculosis using a subcutaneous polymer implant with a large drug load released slowly over a long period. INH delivery by biodegradable poly-(alpha-hydroxy acid) polymers was evaluated using ground polymer and compression molded implants.

DESIGN: Rate of drug release and structural stability of the implant in an aqueous environment were measured, as were in vivo evaluations of the duration of measurable levels of INH in serum and urine.

RESULTS: Factors that influenced the suitability of an implant in an in vitro system included polymer molecular weight and crystallinity, polymer and drug particle size, drug loading dose, and press temperature and pressure. The implant characteristics that most closely approached optimal conditions include a polymer of 100% L-lactide with low intrinsic viscosity, polymer particle size <75 μ, and INH particle = 126–180 μ, INH loading dose not to exceed 46%, and press conditions of 70°C and 345000 kPa. Studies of subcutaneous implants in rabbits and baboons show that INH is released from the implant for 15 to 26 weeks.

CONCLUSIONS: An INH-containing polymer was developed that was structurally stable in an aqueous environment and that released INH over a period of at least 15 weeks. Studies with infected animals will be necessary to determine the dose required for prophylaxis and treatment of active disease.

Keywords: biodegradable implants; isoniazid; polymers; tuberculosis

Document Type: Regular Paper

Affiliations: West Side VA Medical Center and the University of Illinois College of Medicine, Chicago, Illinois, USA

Publication date: November 1, 1999

More about this publication?
  • The International Journal of Tuberculosis and Lung Disease publishes articles on all aspects of lung health, including public health-related issues such as training programmes, cost-benefit analysis, legislation, epidemiology, intervention studies and health systems research. The IJTLD is dedicated to the continuing education of physicians and health personnel and the dissemination of information on tuberculosis and lung health world-wide.

    Certain IJTLD articles are selected for translation into French, Spanish, Chinese or Russian. They are available on the Union website

  • Editorial Board
  • Information for Authors
  • Subscribe to this Title
  • International Journal of Tuberculosis and Lung Disease
  • Public Health Action
  • ingentaconnect is not responsible for the content or availability of external websites
Related content



Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content

Text size:

A | A | A | A
Share this item with others: These icons link to social bookmarking sites where readers can share and discover new web pages. print icon Print this page