Methods: Patients with chronic HBV / HDV co-infection are currently being treated once weekly with 500mg REP 2139-Ca (calcium chelate complex) by 2h IV infusion. Viremia (HDV RNA and HBV DNA), HBsAg and anti-HBs are followed every two weeks using standard assays (Robogene RT-PCR, Abbott RealTime HBV, Abbott Architect) and performed at the Institute of Virology, University of Duisburg-Essen, Germany.
Results: REP 2139-Ca treatment in all patients is currently well tolerated. All patients have experienced reductions in serum HBsAg and HDV RNA on treatment as outlined in the table below. Four patients have achieved HBsAg reductions of 4-5 logs from baseline with accompanying 5-8 log reductions in HDV RNA (currently undetectable). More moderate HBsAg reductions (1-2 logs) in the other three patients were accompanied by similarly moderate (1-3 log) reductions in HDV RNA. Significant elevations in serum free anti-HBs are detectable in 6/7 patients and are > 10 mIU / ml in 4 patients. In the 5 patients with pre-treatment HBV DNA < 10 IU / ml, small amounts of detectable HBV DNA are now present.
Conclusions: REP 2139-Ca is able to achieve rapid reductions in serum HBsAg in Caucasian patients with HBV / HDV infection, demonstrating the reliability of the NAP pharmacological effect (HBsAg reduction or complete clearance) in Caucasian patients. HDV RNA reductions were correlated with HBsAg reductions, suggesting a link between SVP formation and HDV formation. REP 2139-Ca may become an important new therapeutic option for patients with chronic HBV / HDV infection.
[Antiviral response of patients to REP 2139-Ca]
