ProMIS Neurosciences Plunges 28% Intraday—Is This the Catalyst No One Saw Coming?

Summary
• ProMIS Neurosciences (PMN) slumps 28.4% to $0.802 amid $2.4 million PIPE financing and $0.8 million registered offering.
• FDA Fast Track designation for PMN310 announced, yet shares trade near 52-week lows.
• Turnover surges 58% as technicals show overbought RSI and bullish short-term momentum.

ProMIS Neurosciences has experienced one of its most volatile trading days in 2025, with shares plummeting 28.4% to $0.802 amid conflicting signals from equity capital raises and regulatory progress. The stock’s intraday range of $0.77 to $1.03 highlights extreme volatility, while technical indicators suggest a potential reversal. Investors must parse through dilutive financing moves and clinical milestones to gauge the next directional shift.

Fundraising Fears Overshadow FDA Designation
ProMIS’s 28% intraday collapse stems from a $2.4 million PIPE financing and $0.8 million registered offering, which combined with existing warrant exercises, will dilute shareholders and raise $9.2 million. While the FDA Fast Track designation for PMN310—a potential Alzheimer’s therapy—signals regulatory optimism, the aggressive capital raise has triggered a sell-off. The market’s focus appears on the dilutive impact of the warrants, which were issued at $0.1875 per share (a 81% discount to the 52-week high of $1.75). This perceived undervaluation has spooked investors, overshadowing the clinical progress of PMN310.

Biotech Sector Mixed as BIIB Leads Gains
The broader biotech sector showed mixed performance, with Biogen (BIIB) rising 2.9% on updated pipeline guidance. However, ProMIS’s sharp decline contrasts with sector resilience, highlighting its unique challenges. The company’s high debt-to-equity ratio and negative PE (-0.89) further isolate it from peers. While the FDA Fast Track designation aligns with sector trends in neurodegenerative disease innovation, the immediate reaction to ProMIS’s financing has been bearish, contrasting with Biogen’s positive momentum.

Technical Bounce Potential in Overbought RSI
• 200-day average: 0.7767 (above) • RSI: 79.63 (overbought) • MACD: 0.04 (bullish) • Bollinger Bands: Upper at 0.793, Middle at 0.485 • Moving Averages: 30D at 0.492, 100D at 0.581

Technical indicators suggest a potential bounce from overbought RSI levels (79.63) and a bullish MACD crossover. Key support lies at $0.77 (intraday low) and $0.485 (20-day moving average). While the stock is in a long-term ranging pattern, the RSI’s overbought condition (above 70) hints at short-term exhaustion. The absence of leveraged ETFs complicates directional bets, but traders may consider a short-term reversal play if the stock tests $0.77 before rebounding. The options chain is empty, so focus remains on technical setups.

Backtest ProMIS Neurosciences Stock Performance
The performance of PMN after an intraday plunge of -28% was generally negative, with short-term win rates slightly above 40% but overall returns declining over 3, 10, and 30 days. The maximum return during the backtest period was only 0.01%, indicating the strategy's inefficacy in generating positive returns following such a significant downturn.

Watch for $0.77 Breakdown or Regulatory Catalyst
The 28% intraday plunge has pushed ProMIS near critical support at $0.77, with a breakdown below this level likely to trigger further selling. However, the FDA Fast Track designation for PMN310 could act as a floor, especially if interim data from the PRECISE-AD trial (Q2 2026) shows promise. Biogen’s 2.9% gain underscores sector resilience, but ProMIS’s dilutive financing remains a near-term headwind. Investors should monitor the 52-week low of $0.38 and watch for a potential rebound into overbought RSI territory. For now, the path of least resistance appears downward, but regulatory progress could reverse this trend.