About SpotRM


This web-based application for detecting reactive metabolite risks was launched in September 2020. It was made possible through collaboration with Kevin Parkes, with a background as Head of computational chemistry at Medivir. Kevin’s expertise and skills made rapid progress possible and we believe that we have created a very useful tool for drug designers to stay away from many more or less obvious risks for reactive metabolite formation. The development was supported by Alexander Minidis, process/medicinal chemist and data-scientist.


AWAMETOX AB was founded in 2014 by former AstraZeneca medicinal chemist Alf Claesson. Alf has a broad preclinical experience from more than 27 years in the pharmaceutical industry (AstraZeneca 1984-2010 working as a section head/ project leader/ principal scientist) and academia (Uppsala University, Associate Professor).

During the last years at AstraZeneca he worked as Principal Scientist specializing in chemical toxicology, an interest that he has taken further into various entrepreneurial endeavors such as:

  • A desktop version of SpotRM was launched in 2016 as SpotRM+. This now abandoned version was designed by Alf and developed in collaboration with Genetta Soft, Uppsala (Ola Spjuth in particular).
  • In 2012 he launched a freely accessible web application (a simple predecessor, now terminated).
  • In 2011 he set up the site stoprm.org where important literature on RM issues was collected; the review section of this is now found at the current Awametox site.

Alf has published 80+ scientific papers, book chapters and a popular text book on medicinal chemistry (in Swedish). He is co-inventor of many patent applications and holds several patents.

Relevant publications

Non-innocuous Consequences of Metabolic Oxidation of Alkyls on Arenes. A Claesson and K Parkes. J Med Chem. 2022, 65, 11433–11453.

Systematic Approach to Organizing Structural Alerts for Reactive Metabolite Formation from Potential Drugs. A Claesson & A Minidis. Chem Res Toxicol. 2018, 31, 389-411. Note that this reference is somwhat dated since only the desktop version of SpotRM was available at time of  publication.

On Mechanisms of Reactive Metabolite Formation from Drugs. A Claesson & O Spjuth.  Mini-Rev Med Chem 2013, 13, 720-729.

On the mechanism of paracetamol’s analgesic activity and a note on related NSAID pharmacology. A Claesson on Slideshare 2013 (link).

Reactive Metabolites – Hints How to Avoid a Drug Safety Hazard. Presentation by A Claesson on Slideshare 2012 (link).

Risk assessment and mitigation strategies for reactive metabolites in drug discovery and development. RA Thompson, A Claesson et al. Chemico-Biol. Interact. 2011, 192, 65-71.