Company Performance: Alkermes' financial results, including revenue, earnings, and pipeline progress, significantly impact its stock price. Positive clinical trial outcomes and successful drug launches generally drive the price up.

Market Sentiment: Overall investor confidence and broader market trends, such as economic conditions and industry outlook, influence Alkermes' stock alongside other pharmaceutical companies.

Regulatory Events: Approvals or rejections of Alkermes' drug candidates by regulatory bodies (e.g., FDA, EMA) have a direct and often substantial effect on its stock price.

Competition: The presence and performance of competing drugs and companies within Alkermes' therapeutic areas can affect market share and investor perception.

Partnerships/Acquisitions: Strategic collaborations, licensing agreements, or potential acquisition targets involving Alkermes can impact investor confidence and stock value.

Analyst Ratings: Investment bank analysts' ratings and price targets for Alkermes stock often influence investor decisions and therefore the stock price.