ViiV Healthcare announces exclusive license agreement with Shionogi to develop third-generation HIV integrase inhibitor with potential for ultra long-acting dosing intervals

• S-365598 aims to build on the success of dolutegravir and cabotegravir with potential to anchor the next generation of VHC’s future pipeline of innovative long-acting therapies for HIV

ViiV Healthcare, the global specialist HIV company majority owned by GlaxoSmithKline (GSK), with Pfizer and Shionogi as shareholders, today announced an exclusive collaboration and license agreement with Shionogi & Co. Ltd. (Shionogi) for S-365598, a third-generation investigational integrase strand transfer inhibitor (INSTI) with potential for use in ultra long-acting HIV regimens (regimens with dosing intervals of three months or longer).  

Under the terms of the agreement, ViiV Healthcare will make an upfront payment of £20 million to Shionogi, a £15 million payment for the achievement of a clinical development milestone and royalties on net sales. The royalty levels are aligned with those in Shionogi’s existing integrase inhibitor agreements with ViiV Healthcare. Shionogi will contribute to development costs up to an annual maximum.

Kimberly Smith, M.D., MPH, Head of Research & Development at ViiV Healthcare said: “Our 20-year relationship with Shionogi has been incredibly successful, producing what are arguably two of the most important HIV medicines of the last decade. Dolutegravir is now taken by 17 million people globally, and cabotegravir has allowed us to develop the first long-acting regimen for treatment. With today’s announcement about the in-licensing of a third integrase inhibitor from Shionogi, we will continue this collaboration and explore the potential of S-365598 to anchor ViiV Healthcare’s pipeline beyond 2030.”

John Keller, Ph.D., Senior Executive Officer, Senior Vice President, Corporate Strategy Division at Shionogi said: “Many people living with HIV and those vulnerable to acquiring HIV have concerns about daily oral medication, such as the daily reminder of living with HIV, HIV status disclosure and consistency of adherence. Long-acting HIV medications have the potential to bring considerable benefit to these individuals. We are looking forward to continuing to work with ViiV to further advance this innovative approach to HIV therapies.”

Preliminary data has shown that S-365598 has a high genetic barrier and a resistance profile that is distinct from that of dolutegravir and cabotegravir. Its long half-life may support its development as an ultra-long medicine that could be delivered with infrequent dosing of every three months or longer.  

Preclinical studies are underway. ViiV Healthcare and Shionogi intend to initiate first time in human studies with S-365598 by 2023.