Arrowhead starts triple-combo hepatitis B test, triggering J&J payday

Johnson & Johnson has long-standing interest in developing a functional cure for hepatitis B virus. (Raysonho/CC0)

Arrowhead Pharmaceuticals has added a triple-combination arm to its chronic hepatitis B virus (HBV) clinical trial. The cohort will assess ARO-HBV in combination with two undisclosed drugs selected by Johnson & Johnson.

J&J secured the global rights to phase 1/2 RNAi therapy ARO-HBV last year for $175 million up front. The original deal committed J&J to paying a further $50 million when ARO-HBV entered phase 2, but the partners subsequently tweaked this part of the agreement to reward Arrowhead for kicking off an early-phase assessment of a triple combination to glean a preliminary look at its effects.

“Beginning this new triple combination cohort in our ongoing AROHBV1001 study has the potential to generate valuable data rapidly,” Arrowhead CEO Christopher Anzalone said in a statement.

Arrowhead has followed through on its part of the agreement, adding a triple-combination arm to its phase 1/2 and earning a $25 million milestone from J&J in the process. J&J will pay the remaining $25 million previously earmarked for the midphase study start when ARO-HBV enters phase 2.

The partners are yet to share details about the triple combination. Arrowhead described the other two drugs in the combination as “undisclosed agents selected by [J&J’s] Janssen” in its release to disclose the news. And it hasn't updated the entry with details of the new cohort. 

J&J has long-standing interest in developing a functional cure for HBV, leading it to buy Novira Therapeutics and enter into hookups with Sino Biopharmaceutical and Arcturus Therapeutics. The pursuit of HBV has left J&J with a number of drugs aimed at the virus, including a phase 2 capsid protein inhibitor, JNJ-56136379, and a phase 1 DNA vaccine, JNJ-64300535. 

These candidates and J&J’s willingness to bet big on ARO-HBV are testament to the size of the HBV opportunity. The World Health Organization estimates 257 million people worldwide are infected with HBV, and the currently available drugs typically repress replication of the virus rather than cure the patient.