Cytokinetics has signed an agreement to sell a portion of the potential royalty from Amgen on worldwide sales of omecamtiv mecarbil to Royalty Pharma.

Omecamtiv mecarbil is a novel cardiac myosin activator that accelerates the rate-limiting step of the myosin enzymatic cycle and shifts the enzymatic cycle in favour of the force-producing state.

Amgen and Cytokinetics collaborated in 2006 to discover, develop, and commercialise small molecule therapeutics designed to activate cardiac muscle to treat heart failure.

The company will also exercise its option to co-invest $40m with Amgen in the Phase III development programme of omecamtiv mecarbil. 

Following this, Cytokinetics will receive an incremental royalty of up to 4% on increasing sales of omecamtiv outside of Japan.

"As part of the agreement, Cytokinetics sold a 4.5% royalty on potential worldwide sales of omecamtiv mecarbil to Royalty Pharma for $90m."

Cytokinetics president and CEO Robert Blum said: "These key corporate developments underscore our steadfast commitment to the promise of omecamtiv mecarbil for the potential treatment of patients with heart failure, and the prudent advancement of our strategy towards commercialisation.

"We are pleased to align with Royalty Pharma on our shared vision of the significant value of omecamtiv mecarbil and how we may realise that upside under our collaboration agreement with Amgen."

As part of the agreement, Cytokinetics sold a 4.5% royalty on potential worldwide sales of omecamtiv mecarbil to Royalty Pharma for $90m.

Under certain circumstances, the royalty rate purchased is expected to increase up to an additional 1%.

After completing the transaction with Royalty Pharma, Cytokinetics will retain the right to receive more than $600m, as well as double-digit royalties that may be more than 20% on tiered worldwide sales of omecamtiv mecarbil.