TABLE 3.

Efficacy of pretreatment with BCX 2798 or BCX 2855 on rSV(hHN) infection in mice^a

Compound	Dosage (mg/kg per day)	Loss or gain (% ± SD)b of mean wt on postinfection day:			No. of survivors/total no.	Survival rate (%)	Mean day to death ± SDc
		5	7	9
BCX 2798	10	−8.2 ± 5.8	−15.9 ± 6.2	−13.4 ± 9.7	12/12d	100
	5	−16.5 ± 4.8	−22.8 ± 6.8	−18.8 ± 9.4	4/6d	66.7	17.0 ± 6.2
	1	−15.7 ± 4.9	−23.3 ± 4.6	−27.4 ± 5.2	2/12	16.7	12.3 ± 4.2
BCX 2855	50	−10.3 ± 6.4	−17.3 ± 9.3	−13.9 ± 8.9	10/12d	83.3	19.3 ± 3.9
	25	−15.0 ± 6.7	−24.2 ± 4.0	−25.4 ± 9.4	2/6	33.3	14.2 ± 5.3
	10	−13.0 ± 4.9	−20.6 ± 4.0	−24.5 ± 7.5	2/11	18.2	12.2 ± 4.5
PBS	0	−17.1 ± 4.9	−24.9 ± 4.5	−28.6 ± 5.3	3/21	14.2	11.3 ± 4.3

^aBCX 2798 or 2855 were administered intranasally to 129×1/SvJ mice for 5 days beginning 4 h before viral infection with 10^6.5 TCID₅₀. Control mice were infected but were treated only with sterile PBS on the same schedule.

^bDifferences in weight loss between the group of treated mice and the group of control mice were evaluated by using repeating measures analysis of variations.

^cThe mean day to death was the number of days of survival after the lethal challenge with rSV(hHN). Survival curves were estimated by the Kaplan-Meier method.

^dThe number of survivors differed significantly from that in the control group (P < 0.05).