Table 5.

Posaconazole and caspofungin combination regimens exhibiting synergy or antagonism by Bliss independence analysis^a

Isolate	Posaconazole dose (mg/kg/24 h)	Caspofungin dose (mg/kg/24 h)	Ec (95% CI)	Eobs (95% CI)	ΔE	Synergy or antagonism
F16216	40	0.625	0.40 (0.32–0.49)	0.65 (0.56–0.71)	0.25	Synergy
	2.5	40	0.13 (0.09–0.16)	0.35 (0.29–0.41)	0.22	Synergy
	2.5	40	0.13 (0.09–0.17)	0.38 (0.29–0.47)	0.25	Synergy
F11628	40	40	0.37 (0.21–0.53)	0.86 (0.81–0.91)	0.49	Synergy
	40	10	0.43 (0.28–0.58)	0.80 (0.76–0.84)	0.37	Synergy
	40	2.5	0.38 (0.25–0.52)	0.67 (0.54–0.79)	0.29	Synergy
	40	0.625	0.27 (0.19–0.35)	0.61 (0.46–0.75)	0.34	Synergy
	40	0.156	0.19 (0.13–0.24)	0.55 (0.43–0.67)	0.36	Synergy
	10	40	0.31 (0.12–0.50)	0.61 (0.59–0.63)	0.30	Synergy
	10	2.5	0.32 (0.15–0.49)	0.54 (0.51–0.56)	0.22	Synergy
EMFR S678P	2.5	40	0.49 (0.46–0.52)	0.14 (0.11–0.17)	−0.35	Antagonism
	2.5	10	0.50 (0.45–0.55)	0.24 (0.18–0.29)	−0.26	Antagonism
	2.5	0.625	0.53 (0.46–0.60)	0.20 (0.16–0.24)	−0.33	Antagonism

^aE_c, predicted fractional effect based on the Bliss independence equation [E_c = (E_A + E_B) − (E_A × E_B); see Materials and Methods]; E_obs, observed fractional effect in the combination dosing experiment; ΔE, difference between E_c and E_obs (E_obs − E_c).