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Updated: Jul 18, 2026
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Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
The propionic acids: a personal perspective
1Research Department, Boots Co., Nottingham, England.
Journal of Clinical Pharmacology
|April 1, 1992
Summary
The development of ibuprofen for rheumatoid arthritis involved testing various drug classes, ultimately leading to a safer and effective nonsteroidal anti-inflammatory drug (NSAID) option. Ibuprofen
Area of Science:
- Pharmacology
- Drug Discovery
- Rheumatology
Background:
- Limited understanding of drug mechanisms for rheumatoid arthritis in the 1950s.
- Aspirin's analgesic action and anti-rheumatic effects were not well-defined.
- Initial research explored ultraviolet (UV) erythema delay in guinea pigs as a model for drug activity.
Purpose of the Study:
- To discover new drugs for rheumatoid arthritis treatment.
- To identify compounds with both anti-rheumatic and analgesic properties.
- To develop a safer alternative to existing treatments.
Main Methods:
- Screening of substituted phenoxypropionic acids and phenylacetic acids.
- Evaluation of anti-erythemic activity in guinea pigs.
- Clinical trials for rheumatoid arthritis efficacy and adverse reactions (ADRs).
- Iterative refinement of drug candidates based on laboratory and clinical data.
Main Results:
- Substituted phenoxypropionic acids showed anti-erythemic activity but lacked clinical efficacy in rheumatoid arthritis.
- Substituted phenylacetic acids were active but caused significant ADRs.
- Substituted phenylpropionic acids, including ibuprofen, demonstrated a favorable balance of efficacy and tolerability.
- Ibuprofen was launched in 1969 and later approved for over-the-counter (OTC) use due to its safety and effectiveness.
Conclusions:
- Ibuprofen emerged as a successful nonsteroidal anti-inflammatory drug (NSAID) from a systematic drug discovery process.
- Its development highlights the importance of refining testing systems and considering therapeutic indices.
- Ibuprofen offers a safer and effective option for rheumatoid arthritis and other painful conditions compared to aspirin or acetaminophen, especially in overdose.
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