Prothena Shares Get A Boost After Company Slashes Workforce, Lowers 2025 Cash Burn Forecast

Prothena Corp shares climbed 5% in after-hours trading on Friday after the company said it expects to reduce its 2025 net cash burn from operating and investing activities to between $170 million and $178 million. 

The forecast follows a sweeping corporate restructuring that includes discontinuing development of birtamimab, an investigational therapy for AL amyloidosis, expected to reduce annual cash burn by about $96 million, and laying off 63% of its workforce.

The biotech expects to end 2025 with roughly $298 million in cash, cash equivalents, and restricted cash at the midpoint.

The revised cash burn outlook includes an estimated net loss of $240 million to $248 million, incorporating $36 million in non-cash share-based compensation and a $45 million non-cash tax expense related to deferred tax assets.

The operating cost estimate includes $105 million to $110 million tied to birtamimab and reorganization-related expenses, such as severance and contract terminations. 

The company’s board and financial advisors are reviewing strategic options as it pivots to focus on its remaining pipeline and partnered programs. 

Prothena said it is reviewing strategic options as several clinical milestones approach, including Roche’s Phase 3 plans for prasinezumab in Parkinson’s, August data from Prothena’s PRX012 Alzheimer’s trial, and 2026 milestone payments of up to $105 million from partnered programs with Novo Nordisk and Bristol Myers Squibb.

On Stocktwits, retail sentiment was ‘bullish’ amid ‘normal’ message volume.

One user expressed confidence in Prothena’s prospects, indicating the stock may have substantial upside potential and encouraging a broader, long-term perspective on its trajectory.

Another user said the cost and workforce reductions were largely anticipated, adding they plan to sell if shares hold above $6 on Friday following the recent rebound from lows.

The stock has declined 57.9% so far in 2025.

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