Cidofovir(Vistide)

CMX001 (Brincidofovir; HDP-CDV) was developed as an orally active, lipophilic form of cidofovir (CDV); has enhanced activity in vitro and in vivo compared to CDV against certain herpesviruses, adenoviruses and orthopoxviruses.IC50 Value: 5.5 nM (EC50, in PDA at 7 dpi) [3]Target: anti-CMVCMX001 is currently in Phase II clinical studies for development as a therapeutic agent for human CMV, adenovirus and BK virus infections, as well as, for adverse events following smallpox vaccinations.in vitro: In PDA at 7 dpi, the CMX001 50% effective concentration (EC50) was 5.55 nM, the 50% cytotoxic concentration (CC50) was 184.6 nM, and the 50% selectivity index (SI50) was 33.3. The EC90 was 19.7 nM, the CC90 was 5,054 nM, and the SI90 was 256.1. In COS-7 cells, JCV replication was faster and the EC50 and EC90 were 18- and 37-fold higher than those in PDA, i.e., 0.1 μM and 0.74 μM (CC50, 0.67 μM; SI50, 6.7; CC90, 12.2 μM; SI90, 16.5) at 5 dpi [3].in vivo: CMX001 and CDV are equally efficacious at protecting mice from mortality following high ectromelia virus doses (10,000 x LD(50)) introduced by the intra-nasal route or small particle aerosol. Using CMX001 at a 10mg/kg dose followed by 2.5mg/kg doses every other-day for 14 days provided solid protection against mortality and weight loss following an intra-nasal challenge of (100-200) x LD(50) of ectromelia virus [1]. When CMX001 was administered orally to mice infected with HSV-1, mortality was reduced significantly (p≤0.001) with all three dose levels when treatments were initiated 24 h post viral inoculation. When treatments were started 48 h post viral inoculation, 5 and 2.5 mg/kg significantly reduced mortality (p≤ 0.001). If treatments were delayed until 72 h post viral inoculation, CMX001 did not reduce mortality or increase the mean day to death. When mice were infected intranasally with HSV-1 and treatments initiated 24 h post viral inoculation using CMX001 at 5 mg/kg or ACV at 100 mg/kg, virus replication in target organs was reduced by both CMX001 and ACV when compared to vehicle treated mice [2]. Toxicity: Diarrhea was the most common adverse event in patients receiving CMX001 at doses of 200 mg weekly or higher and was dose-limiting at 200 mg twice weekly. Myelosuppression and nephrotoxicity were not observed [4].

Calcium trinatrium diethylenetriaminepentaacetic acid hydrate (Ca-DTPA trisodium salt hydrate) is a metal chelator and a useful antidote (such as acute cadmium intoxication). Diethylenetriaminepentaacetic acid calcium trisodium salt hydrate is a nontoxic inhibitor of CMV replication.

Fomivirsen sodium is an antisense 21 mer phosphorothioate oligonucleotide. Fomivirsen is an antiviral agent that is used cytomegalovirus retinitis (CMV) research, incluiding in AIDs. Fomivirsen sodium binds to and degrades the mRNAs encoding CMV immediate-early 2 protein (required for viral replication), thus providing bioactive effects for CMV retinitis by inhibition of virus proliferation.

HHV protease inhibitor 43 is an irreversible small molecule inhibitor of human herpesvirus (HHV) protease targeting a non-catalytic cysteine (C161) with IC50 of 4 uM (HCMV), exhibits broad-spectrum inhibition of other HHV protease homologs.HHV protease inhibitor 43 demonstrates inhibitor stabilization of HCMV Pr homodimerization, exploiting a conformational equilibrium to block proteolysis.HHV protease inhibitor 43 causes a dose-dependent decrease in HCMV replication in HFF-1 cells with IC50 of 5 uM, with no significant cytotoxicity (CC50>20 uM).

Fomivirsen (ISIS-2922 free base) is an antisense 21 mer phosphorothioate oligonucleotide. Fomivirsen is an antiviral agent that is used cytomegalovirus retinitis (CMV) research, incluiding in AIDs. Fomivirsen binds to and degrades the mRNAs encoding CMV immediate-early 2 protein, thus inhibiting virus proliferation.

SB-734117 is a human cytomegalovirus (HCMV) replication inhibitor that prevents CREB and histone H3 post-translational modifications.

NPP-669 (NPP669) is an orally bioavailable cidofovir (CDV) analogue and prodrug, has increased lipophilicity, improved oral absorption, reduced nephrotoxicity, increased cellular uptake, and increased activity against several dsDNA viruses compared to CDV