TABLE 2.

Activity of benzimidazole nucleosides against betaherpesviruses

Virus (cells)Drug50% inhibitory concn (μM)
Antiviral activityaCytotoxicity stationary cellsbToxicity proliferating cellsbSIc
HCMVAD169 (HFF)GCV4.3 ± 0.4>361144>83
BDCRB0.4 ± 0.3170184 ± 20425
1263W9419.4 ± 18.624358.5 ± 22.113
175X2.2 ± 0.5152143 ± 2869
HHV-6AGS (HSB-2)PFA13.7 ± 8.3>166>166>12
BDCRB>125>104>125
1263W94>125>133>133
175X>125>125>126
HHV-6AGS (SupT-1)CDV11.7 ± 8>15990 ± 18.1>13
BDCRB>12569 ± 3470 ± 12
1263W94>133>108>105
175X>125>104>102
HHV-6BZ-29 (CBL)CDV1.6 ± 0.6>159>159>100
BDCRB>125>109>87
1263W94>106>9870 ± 59
175X95 ± 12>122111.8 ± 14>1.3
  • a Values are the mean ± standard deviation of at least two assays. See Materials and Methods for a description of the assays.

  • b See footnote to Table 1 for description of toxicity assays.

  • c SI, selective index, cytotoxicity in stationary cells/antiviral activity. —, ≤1.