What happened

Shares of Cytokinetics (CYTK 1.75%), a clinical-stage biopharmaceutical company, jumped in afternoon trading after its partner, Amgen (AMGN 0.37%), reported some good news. An improved outlook for Cytokinetics' lead candidate drove the stock 19% higher on Wednesday.

So what

Cytokinetics and Amgen have been working on new heart failure drugs since 2006, and omecamtiv mecarbil, the most advanced new drug candidate they've produced so far, took another step toward commercialization today.

Woman in a suit drawing an upward sloping-arrow in the air with her finger.

Image source: Getty Images.

Amgen's been running an 8,000-patient phase 3 study of omecamtiv mecarbil in heart failure patients since 2016. Cytokinetics stock is on the move today because data monitors completed the study's first planned interim analysis and recommended the study continue without any changes.

Omecamtiv mecarbil should help the heart contract with a little more power, which is exactly what people suffering from heart failure need. If adding the experimental treatment to standard care leads to a significant survival benefit, it could become a blockbuster drug.

Check out the latest earnings call transcript for Cytokinetics.

Now what

Around 7,000 patients have already been enrolled in the Galactic-HF trial, and the study should reach full enrollment in the first half of 2019. But it's still not clear how much longer we'll have to wait before we know if Cytokinetics has a winner on its hands. A pre-specified number of cardiovascular events such as heart attacks are what triggered the interim analysis, and there's no telling when the study will hit the next mark.

Cytokinetics also has a skeletal muscle booster in mid-stage clinical studies for patients with spinal muscular atrophy (SMA) and amyotrophic lateral sclerosis (ALS, also known as Lou Gehrig's disease).

Cytokinetics finished December with $199 million in cash and securities after losing $89 million in 2018. That should be enough to see the company through another two years. There's a chance that Galactic-HF could be finished by then, but I wouldn't bet on it.