Short-term monotherapy with IDX184, a liver-targeted nucleotide polymerase inhibitor, in patients with chronic hepatitis C virus infection.
IDX184 is a liver-targeted prodrug of 2'-methylguanosine (2'-MeG) monophosphate. This study investigated the safety, tolerability, antiviral activity, and pharmacokinetics of IDX184 as a single agent in treatment-naïve patients with genotype-1 chronic hepatitis C virus (HCV) infection. Forty-one patients with baseline HCV RNA ≥ 5 log(10) IU/ml, alanine aminotransferase (ALT) ≤ 2.5× the upper limit of normal, and compensated liver disease were dosed. Sequential cohorts of 10 patients, randomized 8:2 (active:placebo), received 25, 50, 75, and 100 mg of IDX184 once daily for 3 days, with a 14-day follow-up. There were no safety-related treatment discontinuations or serious adverse events. The adverse events and laboratory abnormalities observed for IDX184- and placebo-treated patients were similar. At the end of the 3-day treatment period, changes from baseline in HCV RNA levels (means ± standard deviations) were -0.5 ± 0.6, -0.7 ± 0.2, -0.6 ± 0.3, and -0.7 ± 0.5 log(10) for the 25-, 50-, 75-, and 100-mg doses, respectively, while viral load remained unchanged for the pooled placebo patients (-0.05 ± 0.3 log(10)). Patients with genotype-1a and patients with genotype-1b responded similarly. Serum ALT levels decreased, especially at daily doses ≥ 75 mg. During the posttreatment period, plasma viremia and serum aminotransferase levels returned to near pretreatment levels. No resistance mutations associated with IDX184 were detected. Plasma exposure of IDX184 and its nucleoside metabolite 2'-MeG was dose related and low. Changes in plasma viral load correlated with plasma exposure of 2'-MeG. In conclusion, the results from this proof-of-concept study show that small doses of the liver-targeted prodrug IDX184 were able to deliver significant antiviral activity and support further clinical evaluation of the drug candidate.
Quest Clinical Research, San Francisco, CA, USA. drjay@questclinical.com
Jacob
J
Lalezari
David
D
Asmuth
Arnaldo
A
Casiró
Hugo
H
Vargas
Shannon
S
Lawrence
Gloria
G
Dubuc-Patrick
Jie
J
Chen
Joseph
J
McCarville
Keith
K
Pietropaolo
Xiao-Jian
XJ
Zhou
John
J
Sullivan-Bólyai
Douglas
D
Mayers
D000293:Adolescent; D000328:Adult; D000368:Aged; D000410:Alanine Transaminase / Q000097:blood; D000998:Antiviral Agents / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use*; D019540:Area Under Curve; D003710:Demography; D004311:Double-Blind Method; D016503:Drug Delivery Systems; D005260:Female; D006157:Guanosine Monophosphate / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000493:pharmacokinetics / Q000627:therapeutic use; D006207:Half-Life; D019698:Hepatitis C, Chronic / Q000188:drug therapy* / Q000821:virology; D006801:Humans; D008099:Liver / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D019384:Nucleic Acid Synthesis Inhibitors; D011355:Prodrugs; D012367:RNA, Viral / Q000097:blood / Q000235:genetics; D019562:Viral Load; D055815:Young Adult
D000998:Antiviral Agents; C557801:IDX184; D019384:Nucleic Acid Synthesis Inhibitors; D011355:Prodrugs; D012367:RNA, Viral; D006157:Guanosine Monophosphate; D000410:Alanine Transaminase