Pulmatrix Pivots After Merger Collapse on Chinese Regulatory Hurdles

FRAMINGHAM, MA – March 02, 2026 – Pulmatrix, Inc. (Nasdaq: PULM) finds itself at a critical strategic crossroads after its planned merger with Cullgen Inc. was abruptly terminated. The deal, which had been in the works for over a year, collapsed due to significant delays in securing approval from Chinese regulators, forcing the biopharmaceutical company to immediately pivot and intensify its search for alternative strategic partners.

The announcement sent ripples through the market, with Pulmatrix shares (PULM) plummeting 24% in premarket trading as investors reacted to the uncertainty. The termination, initiated by Cullgen on February 28, 2026, marks a major setback for Pulmatrix, which had already secured stockholder approval for the transaction in June 2025. Now, the company must leverage its portfolio of clinical assets and its proprietary iSPERSE™ inhalation technology to secure a new deal in a competitive landscape.

The Deal's Demise and Regulatory Headwinds

The proposed merger, first announced in November 2024, was intended to combine Pulmatrix's innovative drug delivery platform with Cullgen's pipeline. However, the deal hinged on a crucial and ultimately unattainable condition: approval from the China Securities Regulatory Commission (CSRC).

Throughout 2025, the CSRC's review process became a significant bottleneck. While specific reasons for the delay were not detailed in the company's announcement, the timing aligns with a broader trend of increased scrutiny by Chinese authorities over foreign mergers and acquisitions. This more stringent regulatory environment, often attributed to concerns over national security and data privacy, has created an unpredictable and challenging landscape for cross-border transactions involving Chinese entities. The Pulmatrix-Cullgen deal appears to be the latest casualty of these geopolitical and regulatory complexities.

Signs of trouble were evident as early as December 2025, when both companies mutually agreed to waive the "No Solicitation" clause in their agreement. This move allowed both parties to begin exploring alternative transactions, signaling a lack of confidence that the CSRC approval would be forthcoming in a timely manner. The final termination by Cullgen confirmed those fears, officially ending a merger that had been approved by Pulmatrix shareholders nine months prior.

In a statement, Peter Ludlum, Interim Chief Executive Officer of Pulmatrix, acknowledged the impact of the regulatory hurdles. "Due to the significant delays at the Chinese Regulatory Authority (CSRC) in 2025, we initiated a process earlier this year to identify an alternative reverse merger opportunity for the Company," he commented.

A Race Against Time: The Hunt for a New Partner

With the Cullgen deal officially off the table, Pulmatrix is now in an urgent search for a new strategic path forward. The company confirmed it is advancing existing discussions and actively pursuing other reverse merger opportunities. A reverse merger, where a private company acquires a public one to gain a stock market listing, is a common strategy for companies like Pulmatrix looking to combine assets and access capital markets.

The urgency is underscored by the company's financial position. According to its latest filings, Pulmatrix had $4.8 million in cash and cash equivalents as of September 30, 2025, which it anticipated would fund operations into the fourth quarter of 2026. While the company significantly reduced its R&D expenses in 2025, this cash runway puts pressure on management to secure a transaction that can provide the necessary capital to advance its clinical programs.

Despite the setback, Ludlum expressed optimism, noting he is "encouraged by both the interest we've had to date as well as the recent increase in transaction activity within our industry." This sentiment reflects a broader trend in the biopharmaceutical sector, which saw a rebound in M&A activity in late 2025 and early 2026. Larger pharmaceutical companies are actively seeking to acquire innovative platform technologies and de-risked clinical assets to bolster their pipelines, creating a potentially favorable environment for companies like Pulmatrix that have valuable assets to offer.

The Untapped Value in Pulmatrix's Pipeline

The key to Pulmatrix's future lies in the perceived value of its intellectual property and drug candidates. The company's core asset is its proprietary iSPERSE™ technology, an engineered dry powder inhalation platform protected by approximately 149 granted patents worldwide. This technology is designed to create small, dense, and highly dispersible particles for efficient drug delivery to the lungs, potentially offering faster action and fewer side effects than oral or injectable treatments. This platform is the foundation for a diverse clinical pipeline targeting major diseases with significant unmet needs.

Leading the pipeline is PUR3100, a Phase 2-ready asset for the treatment of acute migraine. An inhaled formulation of dihydroergotamine (DHE), PUR3100 showed promising results in a Phase 1 trial, achieving target therapeutic levels in just five minutes and demonstrating a lower incidence of nausea compared to intravenous DHE. With the global migraine treatment market valued at over $6.5 billion in 2025 and growing, a rapid-acting, well-tolerated inhaled therapy could capture a significant market share.

Next is PUR1800, a Narrow Spectrum Kinase Inhibitor for treating acute exacerbations of Chronic Obstructive Pulmonary Disease (AECOPD). Having completed a Phase 1b study where it was found to be well-tolerated, this candidate targets a critical unmet need within the massive COPD market, which exceeded $21 billion in 2025. AECOPD is a leading cause of hospitalization and mortality for COPD patients, making effective new treatments a high priority.

Finally, PUR1900 is an inhaled formulation of the antifungal drug itraconazole. While a U.S. trial was wound down, Pulmatrix's partner, the Indian pharmaceutical giant Cipla, has advanced the drug into a Phase 3 trial in India. This partnership not only de-risks the asset but also provides Pulmatrix with a potential 2% royalty on future net sales outside the U.S. and a 50/50 profit share on any potential monetization within the U.S. The global antifungal market is a multi-billion dollar industry, and a targeted inhaled therapy offers distinct advantages for respiratory fungal infections.

For Pulmatrix, the collapse of the Cullgen merger is a significant blow. However, the company's future now hinges on its ability to successfully market this valuable portfolio of technology and clinical-stage assets to a new suitor. The coming months will be decisive in determining whether Pulmatrix can navigate this corporate turbulence and find a new partner to help bring its innovative inhaled therapies to patients in need.