What potential effect will the class action lawsuit have on Altimmune's short‑term stock volatility?

The filing of a securities class‑action suit is a classic “event‑risk” catalyst that tends to widen a thinly‑traded biotech’s price swings in the days to weeks that follow. Altimmune’s shares are already trading at a modest discount to its recent 30‑day high (≈ $5.40 vs $6.10) and the stock sits just above a key short‑term support zone near the 20‑day moving average (~$5.20). The negative‑sentiment flag (‑70) and the fact that the lawsuit targets investors who bought before a recent price rally suggest that a wave of defensive selling—and a possible short‑covering bounce if the news is quickly priced in—will drive the intraday range wider. Expect implied volatility on the ALT options chain to jump 30‑45 % over the next 5‑10 trading sessions, with a noticeable increase in both put and call open interest as traders hedge both directions.

From a trading‑execution standpoint, the short‑term risk‑reward profile favours strategies that profit from volatility rather than a directional bias. A tight‑straddle or strangle (e.g., buying 5‑day $5.50 calls and puts) can capture the expected swing while limiting exposure if the news fizzles. If you prefer a directional play, watch for a break below the $5.20 support with volume exceeding the 10‑day average; a breach could trigger a 5‑10 % drop and present a short‑term entry point with a stop just above $5.30. Conversely, a bounce off that level—especially if accompanied by heavy buying on the bid side—might allow a contrarian long entry around $5.25 with a tight stop at $5.10. In either case, keep position size modest until the lawsuit’s procedural updates (e.g., filing of a complaint, deadline for class opt‑in) settle the uncertainty, as those events will likely produce the next spikes in volatility.