MannKind & Liquidia's Plunge: The Expectation Gap on Treprostinil's Future

The sell-off was triggered by a single, disruptive event. On Monday, United Therapeutics unveiled Tresmi, a new soft-mist inhaler formulation of treprostinil. The company called it a "category killer product," designed to solve the primary side effect of its existing dry powder inhaler, Tyvaso DPI. This announcement immediately cast a shadow over the royalty stream that MannKind Corp. (MNKD) depends on. Shares of MannKind plunged 38% on Wednesday after the news, with Liquidia also falling sharply. The market's reaction was a classic "sell the news" move, pricing in the worst-case scenario of franchise cannibalization before the facts were clear.

The core expectation gap now centers on Tresmi's role. Will it simply replace the existing Tyvaso DPI, eroding MannKind's royalty base? Or will it expand the overall market for inhaled treprostinil by attracting patients who previously avoided treatment due to coughing? Analysts see both risks and potential. H.C. Wainwright's Brandon Folkes noted the new product introduces "uncertainty around the long-term durability of Tyvaso DPI royalties," but also suggested the selloff may be "discounting a worst-case scenario before there is clarity." The market is betting heavily on the former, while the company's own description of Tresmi as a "category killer" hints at the latter. This is the central arbitrage: the stock price is currently pricing in a significant royalty hit, but the actual outcome hinges on whether Tresmi creates a new, larger market or just shifts existing sales.

Assessing the Expectation Gap: Cannibalization vs. Market Expansion

The market's initial reaction to United Therapeutics' Tresmi announcement was a clear bet on the worst-case scenario: a direct, immediate cannibalization of MannKind's royalty stream. The expectation gap now is whether that fear is overdone. Analysts see a competing narrative. H.C. Wainwright's Brandon Folkes noted that while Tresmi introduces uncertainty around the long-term durability of Tyvaso DPI royalties, the selloff may be discounting a worst-case scenario before there is clarity on the role a DPI formulation could play in the long-term broader franchise. In other words, the stock price is pricing in a significant royalty hit, but the actual outcome hinges on whether Tresmi creates a new, larger market or just shifts existing sales.

For Liquidia, the regulatory path is a stark example of this expectation gap in action. The company's Yutrepia nebulized formulation received a tentative FDA approval last week. This is a regulatory victory, but a delayed one. The approval is contingent on the expiration of United Therapeutics' three-year regulatory exclusivity for its Tyvaso DPI, which is set for May 23, 2025. This creates a critical timeline for Liquidia. The market's disappointment in the tentative approval reflects the expectation that the company must wait over a year for its product to reach the U.S. market, even though it has met all safety and efficacy standards. The expectation gap here is between the near-term regulatory hurdle and the potential long-term market opportunity.

United Therapeutics itself is actively expanding the market for its treprostinil franchise, which could benefit both MannKind and Liquidia in the long run. The company recently announced positive results from its TETON-2 study, which showed that its nebulized Tyvaso improved absolute forced vital capacity (FVC) by 95.6 mL vs. placebo in patients with idiopathic pulmonary fibrosis (IPF). This is a validation of the drug's anti-fibrotic potential and expands the potential market for inhaled treprostinil beyond its existing pulmonary arterial hypertension and interstitial lung disease indications. If successful, this new label could attract a new patient population, potentially growing the overall pie.

The bottom line is that the expectation gap is not just about one product replacing another. It's about the trajectory of the entire inhaled treprostinil market. The market is currently pricing in a contraction due to Tresmi and a delay for Yutrepia. The competing narrative, supported by United's own IPF data, is one of expansion. The arbitrage opportunity lies in determining which force-cannibalization or market growth-will ultimately dominate.

Financial Impact and Valuation Reassessment

The expectation gap is now translating directly into severe financial pressure and a valuation reset for both companies. For MannKind, the stock's performance tells the story of a de-risked royalty story. Shares have fallen over 33% in the last 20 days, trading near their 52-week low of $3.29. This isn't just a reaction to a single event; it's a sustained de-risking of the core asset that has powered the stock for years. The market is explicitly pricing in a significant reduction in future royalty income from the Tyvaso DPI franchise, with the stock now trading at a PS TTM of 3.7. That multiple is under direct pressure from the new uncertainty, as investors reassess the durability of the cash flow stream.

Liquidia's situation is a study in regulatory vs. commercial timing. The company secured a tentative FDA approval for its Yutrepia nebulized formulation, a clear regulatory win. Yet the market's reaction-a 40% drop in pre-market trading-shows it is pricing in the extended exclusivity period for United Therapeutics' product. The approval is contingent on the expiration of United's three-year regulatory exclusivity for Tyvaso DPI, which is set for May 23, 2025. In other words, the stock is being valued as if the commercial opportunity is delayed by over a year, regardless of the drug's merits. The arbitrage here is between the near-term regulatory hurdle and the long-term market potential, with the current price favoring the former.

The bottom line is that both stocks are in a state of expectation arbitrage. MannKind's valuation is being reset downward on the fear of royalty cannibalization, while Liquidia's stock is being punished for the regulatory delay that follows its own approval. The market is currently betting that the negative catalysts-United's new product and its exclusivity-will dominate. The path to recovery for both will require clear evidence that the broader treprostinil market is expanding, not contracting, a dynamic that remains the central, unresolved question.

Catalysts and What to Watch

The expectation gap will be resolved by a series of near-term events that will test the market's current pessimistic pricing. For MannKind, the key catalyst is United Therapeutics' own roadmap for Tresmi. The company has stated it intends to file for its approval in PAH and ILD this year and commercially launch it next year. This planned 2026 filing and 2027 commercial launch is the first real-world test of the "category killer" narrative. If Tresmi's launch is slow or its uptake is limited, it would support the market's fear of cannibalization. Conversely, a strong launch that expands the overall treprostinil market would validate the competing view that the franchise is growing, not shrinking. The next earnings report from MannKind will be critical for gauging management's updated view. Investors must watch for any changes to the company's guidance or commentary on royalty assumptions, as these will signal whether the company believes its cash flow stream is being permanently impaired.

For Liquidia, the date to watch is May 23, 2025. That is the expiration of United Therapeutics' three-year regulatory exclusivity for Tyvaso DPI, which is the sole remaining barrier to Yutrepia's launch in the U.S. market. The stock's current valuation is effectively priced for a delay of over a year. The arbitrage opportunity hinges on whether this exclusivity period is challenged or shortened. CEO Roger Jeffs has already stated the company plans to take quick action to challenge the FDA's broad grant of regulatory exclusivity. A successful legal or regulatory push to shorten the exclusivity period could dramatically accelerate Liquidia's commercial timeline and reset the stock's trajectory. Until that date, the market will continue to price in the delay, regardless of the drug's clinical merits.

The bottom line is that both companies are now in a waiting game. MannKind's fate is tied to United's product launch and its own guidance. Liquidia's fate is tied to a single regulatory date and the potential for a challenge to that exclusivity. These are the specific events that will either confirm the market's worst-case scenario or force a reassessment of the entire treprostinil franchise's future.