Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Tools for more accurate dosage of drugs against HIV/AIDS and malaria

06.03.2009
A doctoral thesis presented at the Sahlgrenska Academy, University of Gothenburg, Sweden, shows that it is possible to describe and quantify the relationships between dose, concentration and effectiveness of several drugs against HIV/AIDS and malaria. The method may allow improved treatment and fewer undesired effects for patients with these diseases.

Registered pharmacist Daniel Röshammar has in his thesis studied the optimal use of certain pharmaceutical substances that are used to combat HIV/AIDS and malaria. He has analysed, among other things, data from 121 healthy volunteers from Uganda using a mathematical model known as a pharmacometric model.

The study showed that both sex and genetic differences between individuals influence the way in which the body metabolises efavirenz, which is part of some anti-HIV/AIDS drugs. Other studies have focussed on 74 people from Zimbabwe with HIV/AIDS, and showed that a reduction in the daily dose of efavirenz from 600 mg to 400 mg can reduce the risk of undesired effects in those affected who have a genetically conditioned poorer ability to catabolise the substance.

"Many HIV/AIDS patients are treated with efavirenz, and they should be genetically tested using a blood test before deciding on a dose. This is particularly important in Africa, where the fraction of patients with a poorer catabolic ability is greater than it is elsewhere", says Daniel Röshammar.

Repeated measurements of the drug concentrations and virus levels in 239 previously untreated Scandinavian patients with HIV/AIDS allowed a similar model to be used in order to study the antiretroviral effects of anti-HIV/AIDS drugs. Calculations showed that treatment in which efavirenz was combined with other pharmaceutical substances was more effective than two other frequently used combination treatments.

"It may be possible in the future to use the model to predict when the treatment will loose its effectiveness for an individual patient, and explain why", says Daniel Röshammar.

Further work involved using a model to describe how the catabolism of the anti-malarial drug artemisinin increases and the concentration of the drug decreases when patients take this drug. When artemisinin was given to 97 patients in Vietnam without other drugs, approximately 37% of them were affected by recrudescent malaria. The model showed that this could not be explained solely by low drug concentrations. Another anti-malarial drug, piperaquine, may be a suitable partner for artemisinin in the treatment of malaria. An investigation of 12 Vietnamese study subjects, however, allowed scientists to estimate that the levels of piperaquine that remain in the body are too low to be effective, and this increases the risk that the malaria parasite will develop resistance.

"Research shows that pharmacometric models can be adapted to patient data in order to understand the relationships between drug concentration, effectiveness and the progress of disease, while at the same time taking into consideration differences between patients such as, for example, weight, age, sex, genetic factors, other diseases and other drugs. We expect that these tools will be important in the fight against HIV/AIDS and malaria", says Daniel Röshammar.

The thesis has been written by:
Registered pharmacist Daniel Röshammar, telephone: +46 733 924602, e-mail: daniel.roshammar@pharm.gu.se
Supervisor:
Professor Michael Ashton, telephone: +46 31 786 3412, e-mail: michael.ashton@pharm.gu.se
The thesis has been presented for the degree of Doctor of Philosophy (Medicine) at the Sahlgrenska Academy, Institute of Neuroscience and Physiology

Title of the thesis: Applied Population Pharmacokinetic/Pharmacodynamic Modeling of Antiretroviral and Antimalarial Drug Therapy

Press information: Ulrika Lundin
Public relations officer, Sahlgrenska Academy at the University of Gothenburg
Telephone: +46 31 786 3869, +46 70-775 8851
e-mail: ulrika.lundin@sahlgrenska.gu.se

Helena Aaberg | idw
Further information:
http://hdl.handle.net/2077/19044 -

More articles from Health and Medicine:

nachricht Improving memory with magnets
28.03.2017 | McGill University

nachricht Graphene-based neural probes probe brain activity in high resolution
28.03.2017 | Graphene Flagship

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Transport of molecular motors into cilia

28.03.2017 | Life Sciences

A novel hybrid UAV that may change the way people operate drones

28.03.2017 | Information Technology

NASA spacecraft investigate clues in radiation belts

28.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>