HOWL Stock: Insider Activity, Filings & Research

Werewolf Therapeutics, Inc. (HOWL) — Drillr’s hub for HOWL insider activity, SEC filings, earnings signals and AI research. Over the trailing 3 months, HOWL insiders filed 0 open-market buys and 31 sales (SEC Form 4).

Sentiment

0/100

Buys (3m)

Sells (3m)

Net (3m)

-$1.4M

Insider trades by month Buys Sells

Nov

Dec

Jan

Apr

May

Jun

Context3-month price -31%Institutions reducing (13F)

Date	Insider	Type	Shares	Price
Jun 3, 2026	EVNIN LUKEdirector	Sell	29,595	$0.45
Jun 3, 2026	EVNIN LUKEdirector	Sell	29,749	$0.42
Jun 3, 2026	EVNIN LUKEdirector	Sell	80,459	$0.47
May 29, 2026	EVNIN LUKEdirector	Sell	80,852	$0.48
May 29, 2026	EVNIN LUKEdirector	Sell	32,556	$0.45
May 29, 2026	EVNIN LUKEdirector	Sell	27,698	$0.46
May 26, 2026	EVNIN LUKEdirector	Sell	36,387	$0.42
May 26, 2026	EVNIN LUKEdirector	Sell	67,950	$0.47
May 26, 2026	EVNIN LUKEdirector	Sell	87,425	$0.45
May 20, 2026	EVNIN LUKEdirector	Sell	62,970	$0.45
May 20, 2026	EVNIN LUKEdirector	Sell	22,184	$0.50
May 20, 2026	EVNIN LUKEdirector	Sell	85,895	$0.43
May 13, 2026	EVNIN LUKEdirector	Sell	44,679	$0.54
May 12, 2026	EVNIN LUKEdirector	Sell	33,948	$0.67
May 12, 2026	RA CAPITAL MANAGEMENT, L.P.10 percent owner	Sell	6,719	$0.64

Source: HOWL SEC Form 4 filings, latest Jun 3, 2026. For informational purposes only — not investment advice.

Overview

Werewolf Therapeutics, Inc. (NASDAQ:HOWL) is a clinical-stage biopharmaceutical company founded in 2017 and headquartered in Cambridge, Massachusetts. The company went public in April 2021 and focuses on developing innovative cancer immunotherapies using its proprietary PREDATOR platform technology. Werewolf specializes in creating conditionally activated immune-stimulating molecules designed to overcome the limitations of traditional cancer treatments by precisely targeting tumor environments while minimizing systemic toxicity.

Business

Werewolf Therapeutics operates in the oncology immunotherapy sector, which represents a rapidly evolving area of cancer treatment that harnesses the body's immune system to fight tumors. The company's core technology is the PREDATOR platform, which creates conditionally activated molecules called INDUKINE molecules. These are engineered versions of naturally occurring immune-stimulating proteins that remain inactive in healthy tissue but become activated specifically within tumor environments. The concept behind conditionally activated therapeutics addresses a fundamental challenge in cancer immunotherapy: traditional immune-stimulating treatments often cause severe side effects because they activate the immune system throughout the entire body, not just at tumor sites. Werewolf's approach involves modifying powerful immune-stimulating molecules so they only "turn on" when they encounter specific conditions found in tumors, such as particular enzymes or pH levels. The company's pipeline consists of three main product candidates. WTX-124 is a conditionally activated version of Interleukin-2 (IL-2), a protein that stimulates T-cells and natural killer cells to attack cancer. Traditional IL-2 therapy causes significant toxicity, but WTX-124 is designed to minimize these effects by remaining inactive until it reaches tumor tissue. WTX-330 is based on Interleukin-12 (IL-12), another potent immune stimulator that has historically been too toxic for clinical use. WTX-613 utilizes interferon alpha, a protein that can both stimulate immune responses and directly inhibit tumor growth. All three candidates target solid tumors, which are cancers that form masses in organs and tissues, as opposed to blood cancers. WTX-330 also targets lymphomas, which are cancers of the lymphatic system. The company currently generates minimal revenue, with most income coming from research collaborations rather than product sales.

Revenue model

Werewolf Therapeutics currently operates as a pre-revenue clinical-stage biotechnology company, meaning it does not yet generate significant income from product sales. The company's limited revenue of approximately $1.9 million in 2024 came primarily from research collaboration agreements and government grants, representing a substantial decrease from $19.9 million in 2023, which likely included upfront payments from partnerships. The company's business model follows the typical biotech development pathway: raise capital through equity financing and partnerships, use funds to advance drug candidates through clinical trials, and eventually monetize through product sales, licensing deals, or acquisition. Werewolf's ultimate revenue model will depend on successfully bringing its INDUKINE molecules to market, where they would compete in the global oncology market worth hundreds of billions of dollars annually. Several factors could significantly impact Werewolf's future profitability. Positive clinical trial results demonstrating both efficacy and safety advantages over existing treatments would substantially increase the company's value and partnership opportunities. The competitive landscape in cancer immunotherapy is intense, with major pharmaceutical companies and numerous biotechs developing similar approaches. Regulatory approval timelines and requirements from the FDA and international agencies will directly affect time-to-market and development costs. Manufacturing and commercialization costs for biologics like INDUKINE molecules are substantial, typically requiring specialized facilities and expertise. The company will likely need strategic partnerships with larger pharmaceutical companies to handle global commercialization, which would involve revenue-sharing arrangements. Patent protection and intellectual property strength will be crucial for maintaining competitive advantages and pricing power in the market.

Competitive moat

Werewolf Therapeutics possesses a moderate but potentially significant competitive moat centered around its proprietary PREDATOR platform technology and intellectual property portfolio. The company's approach to conditional activation represents a novel solution to a well-recognized problem in immunotherapy - systemic toxicity limiting the use of potent immune-stimulating molecules. The technical complexity of designing conditionally activated biologics creates some barriers to entry, as it requires specialized expertise in protein engineering, tumor biology, and immunology. Werewolf's specific approach to conditional activation through tumor-associated protease cleavage and other mechanisms may provide differentiation from competitors working on similar concepts. However, the moat faces several challenges. The biotechnology industry is highly competitive, with numerous well-funded companies and major pharmaceutical corporations developing alternative approaches to cancer immunotherapy. Large pharmaceutical companies possess substantially greater resources for research, development, and clinical trials, potentially allowing them to outpace smaller biotechs like Werewolf. The conditional activation concept itself is not unique to Werewolf, with other companies exploring similar strategies using different technical approaches. Patent landscapes in biotechnology can be complex and contested, and the ultimate strength of Werewolf's intellectual property protection remains to be fully tested. The company's moat will ultimately depend on clinical trial results demonstrating clear advantages over existing treatments. Without successful clinical outcomes, technological innovation alone provides limited competitive protection. The early-stage nature of the company's pipeline means the competitive position could change significantly based on trial results from both Werewolf and its competitors.

Risks & safety

Werewolf Therapeutics presents a mixed margin of safety profile typical of clinical-stage biotechnology companies, with strong liquidity but significant execution risks. • Liquidity and Solvency: The company maintains a strong cash position with $92.9 million in cash and short-term investments as of Q1 2025, providing substantial runway for operations. Current ratio of 8.1 indicates excellent short-term liquidity, while total debt-to-equity ratio of 0.18 shows minimal debt burden. • Cash Burn: Quarterly operating cash flow burn of approximately $19 million suggests the current cash position provides roughly 4-5 quarters of funding at current spending levels, creating moderate near-term financing pressure. • Valuation Metrics: Trading at 0.76x book value indicates the stock price reflects significant skepticism about future prospects. The company trades below tangible book value, suggesting potential asset-based downside protection. • Other Considerations: As a pre-revenue biotech, traditional valuation metrics are not applicable. The primary risks center on clinical trial failures, regulatory setbacks, and the need for additional financing. The Graham net-net ratio of 0.96 suggests the company trades near its liquidation value, providing some downside protection but also indicating market pessimism about the business prospects.

Recent development

Based on the available financial data, Werewolf Therapeutics has been advancing its clinical pipeline while managing a transition from collaboration-heavy revenue to a more typical clinical-stage profile. The significant decrease in revenue from $19.9 million in 2023 to $1.9 million in 2024 suggests the completion of major upfront collaboration payments, indicating the company is now primarily focused on internal development rather than partnership-driven activities. The company's operating expenses have remained relatively stable, with quarterly cash burn in the $12-19 million range, suggesting disciplined expense management while maintaining clinical development activities. This consistency in spending patterns indicates the company is likely progressing its lead candidates WTX-124, WTX-330, and WTX-613 through planned clinical milestones. The maintenance of a strong balance sheet with over $90 million in cash suggests the company has been successful in recent fundraising efforts, providing runway to advance its pipeline through key clinical inflection points. The reduction in current liabilities from $19.4 million in 2023 to $11.7 million in Q1 2025 indicates improved working capital management and potentially fewer near-term obligations. Without access to recent earnings call transcripts, specific details about clinical trial progress, regulatory interactions, and strategic partnerships are not available from the financial data alone. However, the financial trajectory suggests a company in active clinical development phase, managing resources carefully while advancing its novel conditional activation platform through the regulatory pathway.

HOWL company profile · for informational purposes only — not investment advice.

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