Benzinga | Nov 15, 2021 01:01PM EST

Arrowhead Pharmaceuticals Collaborator Presents Phase 2b Clinical Data From REEF-1 Study In Patients With Chronic Hepatitis B Infection

Arrowhead Pharmaceuticals Inc. (NASDAQ:ARWR) collaborator Janssen Pharmaceuticals, Inc., one of the Janssen Pharmaceutical Companies of Johnson & Johnson, presented clinical data from REEF-1, a Phase 2b study of different combination regimens, including JNJ-73763989 (JNJ-3989), formerly called ARO-HBV, and/or JNJ-56136379 (JNJ-6379), and a nucleos(t)ide analog (NA) for the treatment of chronic hepatitis B virus infection (CHB). The data were presented in a late breaking oral presentation at The Liver Meeting, the Annual Meeting of the American Association for the Study of Liver Disease (AASLD).

JNJ-3989 is an investigational small interfering RNA (siRNA) that targets all hepatitis B virus (HBV) RNAs, thereby reducing levels of all viral proteins. JNJ-6379 is an investigational capsid assembly modulator (CAM-N) that inhibits viral replication by inducing the formation of non-infectious viral particles that are devoid of HBV DNA and RNA. Arrowhead entered into a license and collaboration agreement with Janssen in October 2018 to develop and commercialize JNJ-3989.

REEF-1 (NCT03982186) is a Phase 2b, multicenter, double-blind, active-controlled, randomized study to assess the efficacy and safety over 48 weeks of monthly subcutaneous injections of JNJ-3989 (3 dose levels of 40, 100, and 200mg) and/or 250mg daily oral JNJ-6379 in combination with daily oral NA in currently not treated or virally suppressed patients with HBeAg positive or negative CHB. Patients were required to have HBsAg levels greater than 100 IU/mL to enter the study. The mean baseline HBsAg level was approximately 3.7 log10 IU/mL across all study arms. The primary endpoint of the study is the proportion of patients meeting NA stopping criteria (ALT less than 3 times upper limit of normal, HBV DNA less than the lower limit of quantitation, HBeAg negative, and HBsAg less than 10 IU/mL) at the end of treatment (week 48).