TABLE 1

IC₅₀ values of SID 26681509 against papain and human cathepsins B, G, K, L, S, and V.

Enzyme	IC₅₀						Selectivity Index	% Identity to Cat L
Enzyme		10 min	30 min	60 min	90 min		Selectivity Index	% Identity to Cat L
		μM
Cathepsin L, human liver	0.155 ± 0.012	0.075 ± 0.005	0.056 ± 0.004	0.050 ± 0.003	1	100
Cathepsin V, human, recombinant, NSO cells	1.008 ± 0.146	0.688 ± 0.039	0.618 ± 0.035	0.576 ± 0.024	7-11	78
Cathepsin S, human spleen	1.107 ± 0.134	0.745 ± 0.010	0.724 ± 0.011	0.721 ± 0.029	7-14	55
Papain, C. papaya	6.765 ± 0.367	2.981 ± 0.282	2.600 ± 0.208	1.562 ± 0.314	31-46	48
Cathepsin B, human liver	7.492 ± 0.693	2.983 ± 0.295	2.527 ± 0.073	2.512 ± 0.139	40-50	26
Cathepsin K, human, recombinant, Escherichia coli	17.596 ± 1.040	8.460 ± 0.366	8.442 ± 0.140	6.857 ± 0.063	113-151	58
Cathepsin G, human neutrophil	>50	>50	>50	>50