- Cytokinetics, Incorporated took a step closer Wednesday to earning a $10 million milestone payment from its partner Amgen, reporting positive results from a mid-stage safety and pharmacokinetic study of the long under-development heart drug omecamtiv mecarbil.
- The Phase 2 study tested omecamtiv specifically in Japanese patients with heart failure in order to support inclusion of Japan in the global Phase 3 GALACTIC-HF study, which is being run by Amgen to test cardiovascular outcomes.
- Cytokinetics will earn that $10 million milestone upon first dosing of patient in Japan in GALACTIC-HF. The two companies first teamed up on development of omecamtiv in 2006 and have pressed on despite a clinical failure for an intravenous formulation of the heart failure drug.
Under the agreement between Amgen and Cytokinetics, the big biotech holds an exclusive global license to omecamtiv, which was once seen as a promising candidate for heart failure.
A 2013 setback in the Phase 2 ATOMIC-AHF study seems to have cooled Amgen's enthusiasm for the drug, though. Despite the ongoing Phase 3 outcomes study, omecamtiv is only lightly mentioned in Amgen's recent filings and corporate presentations.
Positive results from a subsequent study kept the program going and Amgen initiated the GALACTIC study last December, with plans to enroll 8,000 symptomatic chronic heart failure patients across 35 countries. Launch of that study triggered a $26.7 million milestone payment to Cytokinetics.
Cytokinetics is eligible for more than $650 million in further milestones provided development continues to progress.
Any future commercialization of omecamtiv would also lead to escalating double-digit royalty payments to Cytokinetics — something the smaller biotech has already traded in part for upfront cash. In February, the company reached an agreement with Royalty Pharma to sell a portion of that future royalty stream — 4.5% — for $90 million upfront in cash and an additional $10 million investment in Cytokinetics stock.
As part of the deal, Cytokinetics said it would exercise its option to co-invest $40 million in Phase 3 development of omecamtiv with Amgen in order to escalate its incremental royalty by up to 4% on future ex-Japan sales of the drug.
While Cytokinetics still touts omecamtiv's blockbuster potential in the U.S., other higher-profile heart failure drugs have struggled commercially. Novartis' Entresto (sacubitril/valsartan), for example, has been slow to gather momentum — despite a strong commercial profile, backing by physician organizations and stepped-up investment by the Swiss pharma.
Those advantages could be starting to shift Entresto's trajectory, but Novartis' experience shows the challenges of demonstrating the value of heart failure drugs in an era of tightening healthcare budgets and cheap generics.
For its part, Cytokinetics seems to be focusing more heavily on its partnered program for amyotrophic lateral sclerosis, or ALS.
That drug, called tirasemtiv, has also hit setbacks. But data from a Phase 3 study is expected in the fourth quarter and could support filings for approval in both the U.S. and Europe.