Why Is ALKERMES PLC (ALKS) Stock Down Today?

ALKS stock fell 7.11% to $43.39 in today's session, driven by a mix of early intraday volatility and investor reaction to recent developments. The stock opened with a modest 0.8% gap up at $43.75 but quickly reversed course, falling to a session low of $43.74 within minutes. The decline followed a series of recent insider sales and ongoing mixed sentiment from analysts, despite positive Phase 1b trial results for Alkermes' ADHD drug candidate ALKS 7290.

What Happened

Alkermes announced positive Phase 1b results for ALKS 7290, showing clinically meaningful improvements in ADHD symptoms with no serious treatment-emergent adverse events. The company plans to move to a Phase 2 trial involving 312 adults, with data expected in 2027. This information was disclosed in a Form 8-K filed on September 21, 2026, under Regulation FD and other events. The news was initially met with optimism, as reflected in a headline from Investing.com, but the stock's performance suggests a more cautious investor response.

In the days leading up to the drop, several analysts raised price targets for ALKS, including JPMorgan, Baird, and Piper Sandler, though JPMorgan maintained a neutral stance. Meanwhile, three executives at Alkermes sold shares in the past two weeks, totaling $4.2 million in disclosed transactions. These insider sales may have contributed to investor uncertainty. Additionally, the company's Q3 sales guidance of $450 million to $470 million came in below the estimated $472.75 million, signaling potential near-term challenges.

What The Data Shows

The stock has been volatile in recent weeks, closing 0.6% lower over the last eight sessions, from $49.61 to $49.30. The current session saw a high of $47.19 and a low of $43.74, with the stock closing at $47.00. Despite the intraday high, volume remained at 0.0M shares, which is 0.0x the 3-month average. The stock is trading within its 52-week range of $26.99 to $55.67, with a market cap of $7.3 billion and a P/E ratio of 111.8.

What To Watch

Investors should monitor the company's Phase 2 trial data expected in 2027 and the scheduled Q3 earnings report for further insight into the drug's development and financial performance.