TABLE 1.

Reversibility of β-l(−) nucleoside analog anti-HBV activity^a

Drug and concn (μM)	Level of HBV DNAb at the following time post-drug removal:
	Day 6	Day 12
l(−)Fd4C
0.02	9	86
0.10	<5	47
0.40	<5	12
l(−)d4C
0.10	6	67
0.50	<5	35
2.00	<5	9
l(−)SddC
0.20	15	63
1.00	5	50
4.00	<5	24

^aAged 2.2.15 cells were treated with drug for 6 days as indicated and cultured an additional 12 days in the absence of drug. Levels of HBV DNA secreted into the culture medium were assessed 6 and 12 days after drug removal. 

^bValues are represented as percentages of HBV DNA levels in untreated control cultures.