Feprazone is an anti-inflammatory compound developed for the treatment of such conditions as osteoarthritis, rheumatoid arthritis, rheumatic fever and gouty arthritis. The drug was tested in phase III of clinical trials, however its further faith is unknown.

Ibuproxam is a prodrug which metabolizes into ibuprofen and is therefore indicated for the treatment of pain and inflammation. Administration of oral ibuproxam resulted in a significantly higher plasma concentration than administration of an equal dose of ibuprofen after 45 minutes. Despite showing some promise as a NSAID ibuproxam does not appear to have been approved or marketed.

Niflumic acid belongs to the group of nonsteroidal anti-inflammatory drugs (NSAIDs) and used in the treatment of rheumatoid arthritis, and joint and muscular pain. Its mechanism of action is believed to be based on selective inhibition of cycloxygenases-2 that results in antipyretic, analgesic, and anti-inflammatory effects. In addition to these effects on prostaglandin synthesis, it has been shown to act as a positive allosteric modulator on α1β2γ2 and as a negative modulator on α6β2 and α6β2γ2 (and α1β2) GABAA receptors. In addition, was reported, that niflumic acid blocked T-type calcium channels. It is available for clinical use in several European countries.

Oxametacin (1-p-chlorobenzoyl-2-methyl-5-methoxy-3-indolylacethydroxamic acid) is a non-steroidal anti-inflammatory compound that exerts analgesic, antipyretic and anti-inflammatory properties. This drug has been claimed to be effective in the treatment of acute attacks of gout. In the antiproliferative test, oxametacin exhibited leukemic cell lines selectivity against the solid tumor cell lines. Oxametacin also exhibited inhibitory activity toward histone deacetylases and thus could be used as a lead compound in the further development of histone deacetylase inhibitors for anticancer therapy.

Flunoxaprofen is a chiral nonsteroidal anti-inflammatory drug (NSAID). It is an arylalkanoic acid derivative. Flunoxaprofen inhibits leukotriene rather than prostaglandin synthesis. Its potency was comparable with that of indomethacin and higher than that of acetyl salicylic acid, ibuprofen or phenylbutazone. The analgesic activity of flunoxaprofen, evaluated by the hot plate method and tail pinching in mice, was slightly lower than that of indomethacin but higher than that of acetyl salicylic acid and ibuprofen. Its adverse reactions profile is similar to the profiles of other NSAIDs, including gastrointestinal disturbances. Flunoxaprofen was withdrawn from clinical use because of concerns of potential hepatotoxicity.

Bumadizone is a non-steroidal anti-inflammatory drug exerting analgesic, antipyretic and anti-inflammatory properties. It has been studied in the treatment of rheumatoid diseases.

In 2012, two newly developed active pharmaceutical ingredients for horses and food producing animals were released on the German market for veterinary drug products. Those are the parenterally applicable first generation cephalosporin Cefalonium (Cepravin) and the nonsteroidal anti-inflammatory drug Suxibuzone (Danilon). Suxibuzone is a d drug for treatment of pain and inflammation associated with musculoskeletal conditions in the horse eg. osteoarthritic conditions, bursitis, laminitis and soft tissue inflammation. It is a prodrug of the phenylbutazone, which inactivates prostaglandin H synthase and prostacyclin synthase

Mofebutazone (or monophenylbutazone) is a 3,5-pyrazolinedione derivative study for treating asthma and muscular pain. It was found that there was no increase in the incidence or severity of the asthmatic attacks during the course of mofebutazone treatment. The drug tended to improve the tested pulmonary ventilatory functions or at least to leave them unchanged. All the mofebutazone-treated individuals showed a dramatic reduction in the concentrations of PGE2, PGF2alpha, and LTs in their BAL, but there was no consistent correlation between the extent of reduction and the degree of benefit or worsening sustained by an individual patient. Mofebutazone was found to be excreted almost exclusively via the kidney

Bucillamine [SA96:N-(2-mercapto-2-methylpropanoyl)-L-cysteine] is a synthetic SH compound and an antirheumatic agent developed from tiopronin. It is mainly used in Japan and Korea. Activity is mediated by the two thiol groups that the molecule contains. Research done in the USA showed positive transplant preservation properties. Bucillamine has the potential to attenuate or prevent damage during myocardial infarction, cardiac surgery and organ transplantation. Bucillamine is a more potent thiol donor than other cysteine derivatives: approximately 16-fold more potent than N-acetylcysteine (Mucomyst(R)) in vivo. In addition bucillamine appears to have additional anti-inflammatory effects unrelated to its antioxidant effect. Oral bucillamine is used clinically in Asia for treatment of rheumatoid arthritis. There is a strong preclinical evidence that parenteral infusion of this agent is efficacious in acute settings characterized by inflammation and oxidative stress. In Phase I human trials healthy volunteers received bucillamine at doses up to 25 mg/kg/h i.v. for 3 h and elicited no serious toxicity. On the basis of pharmacokinetic analyses of blood levels during these studies, it was concluded that bucillamine infused at i.v. doses > or =10 mg/kg/h for 3 h to humans could be expected to be therapeutically effective in myocardial infarction, organ transplantation and other acute inflammatory syndromes. Bucillamine exhibits potent antioxidant activity similar to those of trolox and ascorbic acid. It reduces the stable free radical diphenyl-2-picrylhydrazyl (DPPH). Bucillamine is a potent antioxidant which exerts its beneficial therapeutic activities in RA patients by metal chelation rather than by scavenging free radical species.

Dipyrocetyl (2,3-diacetyloxybenzoic acid) is a drug used as an analgesics and antipyretics. Besides, was shown, that it may be useful in the treatment of acute lung injury (ALI) associated with acute respiratory distress syndrome (ARDS). Dipyrocetyl possesses the anticoagulation properties, which may contribute directly to improve tissue integrity as well as indirectly by the prevention of activation of pro-inflammatory cytokines. In addition, was made a suggestion, that the drug may function as an MMP inhibitor.