The RX-04 program is focused on using a novel binding site within the ribosome to develop new classes of antibiotics to treat some of the multi-drug resistant Gram-positive and Gram-negative infections.
Using Rib-X’s proprietary drug discovery platform, the company has developed three novel classes of antibiotics in less than three years that bind to the ribosome site.
The fourth milestone payment, which was part of the pre-specified terms of the agreement, was for the achievement of research-based milestones.
Rib-X has received $22m to date in upfront and milestone payments under the RX-04 collaboration.
Rib-X may receive up to $86m per product for the achievement of research, development and regulatory milestones and $100m per product for the achievement of commercial milestones.
The company may even receive tiered percentage royalties up to the low double digits on commercial sales.
As per the research agreement Rib-X has the right to co-commercialize one RX-04 product of the company’s choosing with Sanofi in the US.
Rib-X President and CEO Mark Leuchtenberger said this is the fourth milestone they have reached since signing the partnership with Sanofi.