Concert Pharmaceuticals and GlaxoSmithKline (GSK) are collaborating on deuterium-containing medicines in a deal worth over $1 billion. GSK is paying $35 million up front, including a $16.7 million equity investment.
The agreement covers three compounds from Concert’s pipeline: CTP-518, a protease inhibitor for the treatment of HIV expected to enter Phase I trials in the second half of 2009; a preclinical compound for chronic renal disease; and a research product. Concert will also provide GSK with deuterium-modified versions of three GSK drug candidates.
Concert is responsible to complete development of its candidates up to a pre-agreed phase of clinical investigation. Upon completion of such trials or earlier if it chooses, GSK may elect to obtain an exclusive, worldwide license and take over development and commercialization.
Concert is eligible to receive milestones and tiered, double-digit royalties based on deuterium-containing products arising from Concert’s programs. It may also earn milestones as well as royalties on products from the GSK pipeline.
CTP-518 is a novel HIV protease inhibitor developed from Concert’s deuterium chemistry platform by replacing certain key hydrogen atoms of atazanavir with deuterium. Concert has demonstrated in preclinical studies that selective deuterium modification of atazanavir fully retains its antiviral potency but can markedly slow hepatic metabolism, thereby increasing half life and plasma trough levels. As a result, CTP-518 could potentially negate the need to use a protease inhibitor boosting agent such as ritonavir.
Since deuterium is an isotope of hydrogen, deuterium-containing compounds are expected to have similar pharmacological activities as their hydrogen analogs. Additionally, the stronger chemical bond obtained by selective deuterium modification may improve the drug’s metabolic properties.