Antimicrobial activity of aurothiomalate, methotrexate and sulfasalazine against RA associated pathogens
| ATM | MTX | SSZ | |
| Cmax | 1.4–4 µg/mL17 23 | 0.2–0.6 µg/mL24 | 6.0 µg/mL(*) |
| Anaerobic bacteria | |||
| Actinomyces spp (n=6) | >280 µg/mL (70; >280) | n.a. | >600 µg/mL (300; >600) |
| Capnocytophaga spp (n=6) | 35 µg/mL (18; >280) | n.a. | >600 µg/mL (600; >600) |
| Eikenella spp (n=6) | >280 µg/mL (18; >280) | n.a. | >600 µg/mL (300; >600) |
| Fusobacterium spp (n=6) | 53 µg/mL (18; 280) | 30 µg/mL (3.75; >30) | 300 µg/mL (150; 300) |
| Parvimonas spp (n=6) | 210 µg/mL (70; >280) | n.a. | n.a. |
| Prevotella spp (n=6) | >280 µg/mL (>280; >280) | n.a. | n.a. |
| Porphyromonas spp (n=6) | 53 µg/mL (17.5; 140) | n.a. | 450 µg/mL (150; >600) |
| Viridans Streptococci | |||
| Streptococcus spp (n=8) | >280 µg/mL (>280; >280) | 2.3 µg/mL (0.5; 15) | n.a. |
| Aerobic bacteria | |||
| Escherichia coli (n=6) | >280 µg/mL (140; >280) | n.a. | n.a. |
| Proteus mirabilis (n=6) | >280 µg/mL (>280; >280) | n.a. | n.a. |
| Staphylococcus aureus (n=6) | >280 µg/mL (>280; >280) | n.a. | n.a. |
Minimum inhibitory concentrations, presented as median (min; max) µg/mL for disease-modifying anti rheumatic drugs which demonstrated antimicrobial activity in the diffusion disk screening assay.
Cmax, maximum serum concentrations from diverse pharmacokinetic studies, as shown in online supplemental table 1; n.a., not applicable because no antimicrobial activity was observed in the agar diffusion screening assay; For the calculation of median minimum inhibitory concentrations, the highest concentrations tested were used if no inhibition was observed.
*Pharmacokinetic data were taken from the summary of product characteristics (Sulfasalazin-Heyl, Germany).
ATM, Aurothiomalate; MTX, Methotrexate; RA, rheumatoid arthritis; SSZ, Sulfasalazine.