Banking on integrase inhibitors as HIV cornerstone, ViiV bags 3rd-generation compound from Shionogi
As a 12% shareholder of ViiV Healthcare, Japan’s Shionogi has commanded a much lower profile than its fellow owners, GlaxoSmithKline and Pfizer. But behind the scenes, it’s played an outsized role in the development of ViiV’s HIV drugs, coming up with the two top programs — the integrase inhibitors dolutegravir and cabotegravir — currently in ViiV’s portfolio.
And it’s time for round three.
ViiV is paying Shionogi £20 million ($27 million) in cash to license S-365598, which it’s calling a third-generation integrase inhibitor. On the hook for an additional £15 million milestone payment and royalties on par with its previous deals, Shionogi will chip in on development costs up to an annual maximum. First-in-human trials are slated for 2023.
Both dolutegravir and cabotegravir are being deployed as part of approved HIV treatment regimens: Dovato, a pill consisting of dolutegravir and lamivudine, is taken by an estimated 17 million around the world, while cabotegravir plus rilpivirine was approved earlier this year as Cabenuva.
The company added Tuesday that cabotegravir has scored a priority review as pre-exposure prophylaxis, commonly referred to as PrEP.
“Our belief is that integrase inhibitors should anchor regimens of the present and the future,” Kim Smith, R&D chief at ViiV, told Endpoints News. “We will add in medicines that have novel mechanisms of action, like our maturation inhibitor, like capsid inhibitors, like our broadly neutralizing antibodies that we’ll look to combine with the integrase inhibitors, but we like the foundation of an integrase inhibitor.”
On top of a “unique resistance profile” seen in preclinical experiments that point to high potency, Smith said S-365598 appears to have a half life longer than cabotegravir, which has shown to last two months maximum.
“The future is all long-acting,” she said.
Her team has been hard at work striving toward that future, most recently teaming up with Halozyme to explore subcutaneous administrations that could be dosed at longer intervals.