Cytokinetics Shares Jump 40.45% on Aficamten HCM Data $630M Volume Ranks 162nd

Cytokinetics (CYTK) surged 40.45% on Sept. 2, with a trading volume of $630 million, a 450.92% increase from the previous day, ranking 162nd in trading volume for the session. The stock’s rally followed the release of new clinical data for its investigational drug aficamten at the European Society of Cardiology Congress 2025.

The biopharmaceutical company highlighted long-term safety and efficacy results from the MAPLE-HCM trial, showing aficamten’s superiority over metoprolol in improving cardiac function for patients with obstructive hypertrophic cardiomyopathy (HCM). Data indicated no significant increase in atrial fibrillation risk during extended treatment, with adverse events comparable to placebo across 463 participants. The drug remains under regulatory review in the U.S., with a PDUFA decision date of Dec. 26.

Analysts noted the trial outcomes as a key driver for the stock’s performance. H.C. Wainwright reiterated a “Buy” rating with a $120 price target, while Stifel Nicolaus raised its target to $96 after the company’s investor event. The stock’s 52-week high of $59.39 and low of $29.31 remain benchmarks for near-term volatility.

Backtested results from clinical data show aficamten improved exercise capacity and cardiac structure in patients, with consistent safety profiles over time. These findings align with the company’s ongoing regulatory submissions and partnerships to advance HCM treatment options.