Rapport Inks $328M Deal to Bring Precision Seizure Drug to Greater China

BOSTON and SHANGHAI – March 09, 2026 – Rapport Therapeutics (Nasdaq: RAPP) has secured a major strategic partnership with Tenacia Biotechnology, granting Tenacia exclusive rights to develop and commercialize its promising neuroscience asset, RAP-219, in Greater China. The deal, valued at up to $328 million, marks a significant step in the global expansion of a potential new class of precision medicine for neurological and psychiatric disorders.

Under the terms of the agreement, Boston-based Rapport will receive a $20 million upfront cash payment. The company is also eligible for up to $308 million in potential development and commercialization milestones, in addition to tiered royalties on net sales in mainland China, Hong Kong, Macau, and Taiwan. The collaboration leverages Tenacia's regional expertise to accelerate the development of RAP-219, which is being investigated for focal onset seizures (FOS), primary generalized tonic-clonic seizures, and bipolar mania.

A Strategic Gateway to an Underserved Market

This partnership is more than a simple licensing agreement; it is a strategic move to unlock the vast and underserved Central Nervous System (CNS) market in Greater China. Tenacia, a commercial-stage biopharma founded by Bain Capital in 2022, is specifically focused on bringing innovative neurological therapies to the region. Its established network of local investigators is expected to be instrumental in accelerating clinical trials for RAP-219.

The need for new treatments is substantial. China is home to approximately 10 million people with epilepsy, with studies suggesting that as many as 6 million have an active form of the condition. A significant treatment gap persists, with estimates indicating that 40-60% of individuals with active epilepsy do not receive consistent anti-seizure therapy. Similarly, while bipolar disorder is often underdiagnosed due to social stigma, its prevalence is believed to be increasing, potentially affecting millions who lack access to effective, modern treatments.

"This partnership with Tenacia represents an important step in the global development of RAP-219 and advancement of our precision neuroscience portfolio,” said Abraham N. Ceesay, chief executive officer of Rapport, in the official announcement. “Tenacia brings deep expertise in CNS development and commercialization in Greater China, and we believe Tenacia’s robust network of local investigators will accelerate the development of RAP-219 and broaden patient access to this potential best-in-class therapy worldwide."

For Tenacia, the deal adds a highly promising, late-stage asset to its pipeline. "There remains substantial unmet need for innovative treatments in epilepsy and bipolar disorder in Greater China," stated Xiaoxiang Chen, chief executive officer of Tenacia. "RAP-219 represents a highly differentiated and promising potential therapy with compelling data in FOS and significant potential across multiple neurological and psychiatric indications."

The Science of Precision: A Closer Look at RAP-219

At the heart of the deal's excitement is the novel science behind RAP-219. It is a potential first-in-class TARPγ8-specific AMPA receptor negative allosteric modulator (NAM). In simpler terms, it is designed to turn down the activity of a specific protein, TARPγ8, which is found almost exclusively in brain regions like the hippocampus and neocortex where focal seizures often originate.

This neuroanatomical precision is a key differentiator from many conventional CNS drugs. Traditional AMPA receptor inhibitors affect the entire brain, often leading to debilitating side effects such as sedation, dizziness, and cognitive impairment because they also act on regions like the hindbrain. By selectively targeting TARPγ8, RAP-219 aims to deliver therapeutic effects directly to the source of the problem while sparing other areas, potentially offering a much cleaner safety and tolerability profile.

The promise of this approach was validated in a Phase 2a trial for patients with drug-resistant FOS. The results were compelling: patients treated with RAP-219 saw a median reduction in clinical seizures of 77.8%. Furthermore, 72% of patients achieved a clinically meaningful 50% or greater reduction in seizures, and an impressive 24% of patients were completely seizure-free during the 8-week treatment period. The drug was generally well-tolerated, with most side effects being mild to moderate.

Fueling the Pipeline with Non-Dilutive Capital

The financial structure of the collaboration provides a significant boost to Rapport's strategy. The $20 million upfront payment and the potential for an additional $308 million in milestones represent a major infusion of non-dilutive capital. For a clinical-stage company, this type of funding is critical as it provides resources to advance the pipeline without diluting the ownership stake of existing shareholders.

This capital strengthens Rapport’s financial position, allowing it to move forward confidently with its ambitious development plans. The company is preparing to initiate two global Phase 3 registrational trials for RAP-219 in FOS in the second quarter of 2026. Tenacia's involvement is expected to accelerate this timeline by adding clinical trial sites in China. The funding also allows Rapport to continue investing in its broader RAP technology platform, which includes programs targeting chronic pain, hearing disorders, and other neurological conditions.

"The agreement also strengthens our financial position through non-dilutive capital and allows us to continue investing in our highest-priority programs while maintaining a disciplined and capital-efficient strategy," Ceesay added in his statement.

Navigating a Crowded Field with a Differentiated Asset

RAP-219 will enter a market with established treatments, but its unique mechanism provides a clear path for differentiation. In epilepsy, despite the availability of nearly 20 anti-seizure medications in China, up to 40% of patients with focal epilepsy are drug-resistant, meaning they continue to have seizures. This large population represents a significant unmet need for which RAP-219's novel, targeted approach could be a game-changer.

In bipolar mania, the current standards of care include mood stabilizers like lithium and various atypical antipsychotics. These treatments, while effective for many, come with their own sets of side effects and do not work for all patients. Rapport is currently evaluating RAP-219 in a Phase 2 trial for bipolar mania, hoping its targeted action in the hippocampus—a brain region implicated in the disorder—will yield a new and better-tolerated treatment option.

With the backing of Tenacia in a key global market and a pivotal Phase 3 program on the horizon, Rapport is well-positioned to advance what could be the next major innovation in precision neuroscience.