PMX 205 is an effective complement antagonist of the C5a receptor.

In the MTT assay, in 24 h plate, it shows that all groups are significant when compared with negative control group. For the PMX 205 group, the value recorded is between 0.09893 to 0.2465, EP54 group, 0.02724 to 0.1748, and Tamoxifen group, the value recorded in between 0.09880 to 0.2464. Only one group shows a significant result for the 72 h plate, PMX 205 (antagonist group) with the value recorded in between 0.02136 to 0.5322. Only two groups show a significant result for the 48 h plate of incubation time, which are PMX 205 and Tamoxifen. The values recorded are between 0.04987 to 0.3273 and 0.5777 to 0.8551 respectively [1].

PMX 205 (1 mg/kg/day; SOD1G93A rats; p.o.) administered from two-time points (days 28 and 70) before the onset of major clinical symptoms significantly extends survival time compared with untreated rats (p=0.022, day 28; p=0.015, day 70), without clear differences between the two regimens. Treated animals show reduced astroglial proliferation in the lumbar spinal cord and lower end-stage motor scores. In Tg2576 mice, PMX 205 (20 μg/mL in drinking water, n=17) administered from 12 to 15 months of age significantly reduces fibrillar plaque load and hyperphosphorylated tau (69%) compared to untreated controls (n=11).