What Aculys Pharma does

Aculys Pharma, Inc. was a Tokyo-headquartered, clinical-stage biopharmaceutical company that developed and commercialized innovative neurological and psychiatric therapies for the Japanese and broader Asia-Pacific market. Founded in January 2021 by Catalys Pacific, the company pursued a licensing-led model, in-licensing drugs already approved in the US and EU from Western developers to address Japan's documented drug lag/drug loss problem (72% of EU/US-approved drugs remained unapproved in Japan as of 2020). The company's therapeutic focus areas were refractory epilepsy, status epilepticus, narcolepsy, and obstructive sleep apnea syndrome (OSAS).

Aculys's pipeline consisted of two core assets. The first was Spydia® Nasal Spray (diazepam), an intranasal formulation licensed from Neurelis, Inc. (US), approved by Japan's MHLW in June 2025 as Japan's first intranasal anti-seizure medication and the first rescue medication approved for adults for out-of-hospital use. The second was pitolisant (BF2.649), a selective histamine H3 receptor antagonist/inverse agonist licensed from Bioprojet SCR (France) for narcolepsy and OSAS, which had received orphan drug designation and for which NDA submission was planned by end-2025. Both products received orphan drug designation from MHLW, providing priority examination (review period reduced from 12 to 9 months) and regulatory exclusivity in their designated indications.

Aculys monetized its assets through prescription pharmaceutical product sales in Japan under NHI pricing, combined with milestone payments and royalties payable under its in-licensing arrangements. Following Viatris Inc.'s completion of the acquisition in October 2025, commercialization of Spydia® transitioned to Viatris Pharmaceuticals Japan G.K., with Aculys continuing as part of the Viatris Japan Group. Total capital raised across three rounds was approximately JPY 14 billion. End-user demand was fragmented across hospital and specialty clinic prescribers (neurologists, psychiatrists, epileptologists) treating Japan's estimated 600,000-1,000,000 epilepsy patients and the underdiagnosed narcolepsy/OSAS populations, while upstream revenue concentration was anchored on the Neurelis and Bioprojet licensing partnerships.

Name

Aculys Pharma

Legal name

Aculys Pharma, Inc.

Website

https://aculys.com

Company type

Private

Founded year

2021

Operating status

Acquired

Headcount range

11–50 employees

Short description

Aculys Pharma was a Tokyo-based clinical-stage biopharmaceutical company that in-licensed and developed innovative neurological drugs—Spydia® nasal spray for epilepsy and pitolisant for narcolepsy—for Japan and Asia-Pacific before being acquired by Viatris in October 2025.

Ownership category

akta.pro rank

Product category

Neurology Pharmaceuticals

NAICS

Pharmaceutical Preparation Manufacturing (325412), Pharmaceutical and Medicine Manufacturing (3254)

SIC

Pharmaceutical Preparations (2834), Wholesale-Drugs, Proprietaries & Druggists' Sundries (5122)

akta.pro primary industry

Neurology & Psychiatry (CNS) Pharmaceuticals (HLAIAAAF)

akta.pro secondary industry

Neurology & CNS Specialty Pharmaceuticals (HLAIACAC)

Keywords

• Neurology pharmaceuticals
• Antiepileptic drugs
• Nasal spray formulations
• Sleep disorder treatments
• Clinical-stage biopharmaceuticals

Headquarters

HQ city

Tokyo

HQ country

Japan

HQ region

Asia

Offices1 record

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Technology or R&D, Personnel, Marketing or Sales, Operations

Revenue model

1. Pharmaceutical Product Sales: Revenue generated from the sale of prescription pharmaceuticals. Aculys Pharma received marketing approval for Spydia® Nasal Spray (diazepam) in June 2025 and launched the product in December 2025 through Viatris Pharmaceuticals Japan.
2. Licensing and Royalty Revenue: The company held exclusive development and commercialization rights for Japan and Asia-Pacific regions for pitolisant (from Bioprojet) and diazepam nasal spray (from Neurelis). Post-acquisition by Viatris, the deal structure included upfront payment, additional contingent consideration upon regulatory and commercial milestones, and royalties on net sales.

Go-to-market motion2 records

Distribution channels1 record

Marketing channels3 records

Core offering

Aculys Pharma develops and commercializes innovative prescription pharmaceuticals for neurological and psychiatric disorders in Japan and the Asia-Pacific region, focusing on drugs already approved in the US/EU to address Japan's drug lag. The company's portfolio includes Spydia® Nasal Spray (diazepam), Japan's first intranasal anti-seizure medication approved for status epilepticus, and pitolisant, a histamine H3 receptor antagonist in development for narcolepsy and obstructive sleep apnea syndrome. Both products were licensed from international partners (Neurelis and Bioprojet) and are targeted at Japanese patients with high unmet medical needs.

Product overview

Aculys Pharma is a clinical-stage biopharmaceutical company focused on neurological and psychiatric diseases. Its portfolio consists of two products: Spydia® Nasal Spray (diazepam), approved in Japan in June 2025, which is Japan's first intranasal anti-seizure medication and the first rescue treatment approved for adults outside of hospital settings; and pitolisant (BF2.649), a histamine H3 receptor antagonist/inverse agonist in late-stage development for narcolepsy and obstructive sleep apnea syndrome. Both products were sourced from international licensing partners (Neurelis for diazepam, Bioprojet for pitolisant) to address Japan's drug lag and drug loss challenges.

Differentiator

Problem solved

Functional benefit

Brands

• Spydia®: Spydia® Nasal Spray - diazepam nasal spray product for treatment of status epilepticus, first intranasal anti-seizure medication approved in Japan

Products and services

• Spydia® Nasal Spray (diazepam) Japan's first intranasal anti-seizure medication, approved for the treatment of status epilepticus or seizures with potential progression to status epilepticus in patients 2 years or older. It is also the first rescue medication approved for adults for out-of-hospital use. Available in 5mg, 7.5mg, and 10mg doses. Developed by Neurelis, Inc. and commercialized in Japan and Asia-Pacific by Aculys Pharma.
• Pitolisant (BF2.649) A selective histamine H3 receptor antagonist/inverse agonist for treatment of excessive daytime sleepiness in narcolepsy (Type 1 and Type 2) and obstructive sleep apnea syndrome (OSAS). It targets the sleep-wake rhythm regulation by binding to autoreceptors in the presynaptic region of histamine-containing neurons. Approved in 38 countries globally; licensed from Paris-based Bioprojet SCR for Japan.

Quantifiable outcome

• Spydia® Nasal Spray demonstrated efficacy meeting primary endpoint in Phase 3 clinical trial with proportion of patients achieving seizure resolution within 10 minutes and remaining seizure-free for 30 minutes post-dose
• +3 more outcomes

Segments2 records

Ideal customer profiles2 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature2 records

Partnerships

Three partnerships are on record, tiered core.

• Viatris Inc.coreStrategic or Co-development Partner · 1 October 2025Viatris completed acquisition of Aculys Pharma in October 2025, gaining rights to develop and commercialize Spydia® (diazepam nasal spray) and pitolisant in Japan and Asia-Pacific regions. Deal structure included upfront payment, contingent consideration for regulatory and commercial milestones, and royalties on net sales.
• Neurelis, Inc.coreOEM/ Whitelabel/ Licensing Partner · 1 November 2021Licensing agreement for exclusive development and commercialization rights in Japan and Asia-Pacific region (excluding Greater China and Singapore) for diazepam nasal spray (NRL-1). Neurelis developed the nasal spray formulation and FDA approved it as VALTOCO® in 2020 for seizure clusters in epilepsy patients 6 years and older.
• Bioprojet SCRcoreOEM/ Whitelabel/ Licensing Partner · 1 July 2021Licensing agreement for exclusive development and commercialization rights in Japan for pitolisant (histamine H3 receptor antagonist/inverse agonist). Pitolisant was discovered by Paris-based Bioprojet and approved by EMA in 2016 for narcolepsy and in 2021 for OSAS, and by FDA in 2019 for narcolepsy EDS and 2020 for cataplexy.

Scale indicators6 records

Recent moves6 records

Expansion highlights6 records

Direct peers

• UCB S.A. Belgian specialty pharma with a leading epilepsy franchise (Vimpat, Briviact, Fintepla). Comparable as a CNS-focused innovator with strong epilepsy commercialization capabilities; UCB's recent push into narcolepsy through the Zogenix acquisition mirrors Aculys' pitolisant play.
• Avadel Pharmaceuticals: Specialty pharma focused on sleep disorders with Lumryz (once-nightly sodium oxybate) for narcolepsy. Comparable as a focused narcolepsy competitor with reformulation strategy in the same indication Aculys targets with pitolisant.
• Jazz Pharmaceuticals: Specialty pharma with leading franchises in narcolepsy (Xyrem/Xywav, Sunosi) and epilepsy (Epidiolex). Directly comparable as a CNS-focused commercial-stage specialty pharma in the same narcolepsy and epilepsy indications Aculys targets with pitolisant and Spydia®.

Others

• Neurelis, Inc. US-based originator of diazepam nasal spray (Valtoco) and Aculys' licensor for Spydia®. Adjacent enabler rather than direct competitor; Neurelis is the upstream partner that grants Aculys Japan/APAC rights to the NRL-1 intranasal diazepam technology.
• Bioprojet SCR: French originator and licensor of pitolisant to Aculys. Listed as an adjacent party rather than a direct peer: Bioprojet is Aculys' upstream partner for pitolisant and an established European CNS specialty player.

Broad incumbents

• Otsuka Pharmaceutical: Major Japanese pharma with strong CNS/psychiatry portfolio (abilify, brexpiprazole). Comparable for Japan-domestic neurology and psychiatry commercialization, though Otsuka's franchise is broader and more mature.
• Eisai Co., Ltd. Japan's leading neurology-focused major pharma with deep CNS franchise (epilepsy, dementia, neurology). Comparable as a domestic Japanese pharmaceutical operator with established neurology sales infrastructure and regulatory expertise, though at far larger scale than Aculys.
• Takeda Pharmaceutical: Japan's largest pharma with broad CNS and rare disease footprint (post-Shire). Comparable as a domestic incumbent providing the talent pipeline from which Aculys recruited leadership (e.g., former Takeda exec Hidemasa Tanigaki), and as a benchmark for Japanese CNS commercialization at scale.
• Sumitomo Pharma (formerly Sumitomo Dainippon Pharma): Japanese mid-cap pharma with material CNS and psychiatry presence (latuda, growth in neurology pipeline). Directly comparable as a Japan-headquartered player addressing similar neurological and psychiatric indications, with overlapping physician call points.

Emerging players

• SK Biopharmaceuticals: Korean/Asian-origin CNS specialist with cenobamate (Xcopri) for epilepsy. Comparable as a smaller Asia-rooted neurology player commercializing globally, mirroring Aculys' Japan-plus-Asia-Pacific licensing model with novel epilepsy therapeutics.

Market position

Strengths4 records

Weaknesses4 records

Competitive moat4 records

Key risks5 records

Key highlights7 records

Customer concentration

• LinkedInlinkedin.com/company/aculys

Revenue estimate

Valuation estimate

Number of profiles

Profiles5 records

Funding overview

Funding rounds2 records

Investors11 records

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Aculys Pharma