ADEMPAS Drug Patent Profile

Which patents cover Adempas, and when can generic versions of Adempas launch?

Adempas is a drug marketed by Bayer Hlthcare and is included in one NDA. There are four patents protecting this drug and one Paragraph IV challenge.

The generic ingredient in ADEMPAS is riociguat. Two suppliers are listed for this compound. Additional details are available on the riociguat profile page.

DrugPatentWatch^® Litigation and Generic Entry Outlook for Adempas

A generic version of ADEMPAS was approved as riociguat by MSN on September 1^st, 2022.

Summary for ADEMPAS

US Patents:	4
Applicants:	1
NDAs:	1
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for ADEMPAS

Paragraph IV (Patent) Challenges for ADEMPAS

Tradename	Dosage	Ingredient	Strength	NDA	ANDAs Submitted	Submissiondate
ADEMPAS	Tablets	riociguat	0.5 mg, 1 mg, 1.5 mg, 2 mg and 2.5 mg	204819	3	2017-10-10

US Patents and Regulatory Information for ADEMPAS

ADEMPAS is protected by seven US patents.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Bayer Hlthcare	ADEMPAS	riociguat	TABLET;ORAL	204819-004	Oct 8, 2013	AB	RX	Yes	No	7,173,037		Y	Y
Bayer Hlthcare	ADEMPAS	riociguat	TABLET;ORAL	204819-005	Oct 8, 2013	AB	RX	Yes	Yes	11,203,593		Y	Y
Bayer Hlthcare	ADEMPAS	riociguat	TABLET;ORAL	204819-005	Oct 8, 2013	AB	RX	Yes	Yes	12,503,469		Y
Bayer Hlthcare	ADEMPAS	riociguat	TABLET;ORAL	204819-001	Oct 8, 2013	AB	RX	Yes	No	12,503,469		Y
Bayer Hlthcare	ADEMPAS	riociguat	TABLET;ORAL	204819-004	Oct 8, 2013	AB	RX	Yes	No	10,662,188		Y	Y
Bayer Hlthcare	ADEMPAS	riociguat	TABLET;ORAL	204819-001	Oct 8, 2013	AB	RX	Yes	No	7,173,037		Y	Y

International Patents for ADEMPAS

When does loss-of-exclusivity occur for ADEMPAS?

Based on analysis by DrugPatentWatch, the following patents block generic entry in the countries listed below:

Australia

Brazil

Canada

Chile

China

Costa Rica

Cuba

Dominican Republic

Eurasian Patent Organization

European Patent Office

Hong Kong

Japan

Mexico

Morocco

Nicaragua

Peru

Philippines

Singapore

South Korea

Tunisia

Generics may enter earlier, or later, based on new patent filings, patent extensions, patent invalidation, early generic licensing, generic entry preferences, and other factors.

See the table below for additional patents covering ADEMPAS around the world.

Country	Patent Number	Title	Estimated Expiration
Australia	2014220801
Brazil	112015019571
Canada	2807859
Canada	2901636
Chile	2015002304	Formas del metil {4,6-diamino-2- [1- (2-fluorobencil)-1h-pirazolo [3,4-b] piridino-3-il] pirimidino-5-il} metil carbamato
China	105102457	Forms of methyl {4, 6-diamino-2-[1-(2-fluorobenzyl)-1h-pyrazolo[3, 4-b]pyridino-3-yl]pyrimidino-5-yl}methyl carbamate

Supplementary Protection Certificates for ADEMPAS

Patent Number	Supplementary Protection Certificate	SPC Country	SPC Expiration	SPC Description
1506193	36/2014	Austria		PRODUCT NAME: RIOCIGUAT; REGISTRATION NO/DATE: EU/1/13/907 20140331
1506193	SPC/GB14/044	United Kingdom		PRODUCT NAME: RIOCIGUAT, I.E. METHYL N-(4,6-DIAMINO-2-(1-(2-FLUOROBENZYL)-1H-PYRAZOLO (3,4-B)PYRIDIN-3-YL)-5-PYRIMIDINYL(METHYL)CARBAMATE,OR A PHARMACEUTICALLY ACCEPTABLE SALT OR HYDRATE THEREOF.; REGISTERED: UK EU/1/13/907 20140331
1506193	14C0032	France		PRODUCT NAME: RIOCIGUAT,SES SELS,SES ISOMERES ET SES HYDRATES.; REGISTRATION NO/DATE: EU/1/13/907/001-015 20140327
1506193	165 5014-2014	Slovakia		PRODUCT NAME: RIOCIGUAT; REGISTRATION NO/DATE: EU/1/13/907 20140327
1506193	PA2014018,C1506193	Lithuania		PRODUCT NAME: RIOCIGUATUM; REGISTRATION NO/DATE: EU/1/13/907/001 - EU/1/13/907/015 20140327
1506193	2014C/030	Belgium		PRODUCT NAME: RIOCIGUAT; AUTHORISATION NUMBER AND DATE: EU/1/13/907 20140331

ADEMPAS (riociguat) Investment Scenario and Fundamentals Analysis: Patent/Exclusivity Timeline, Competitor Risk, and FDA/Commercial Exposure

Last updated: July 30, 2026

Executive summary

• ADEMPAS (riociguat) is a niche, high-cost pulmonary hypertension franchise with a concentrated payer mix, off-label sensitivity, and pricing pressure typical of specialty cardiovascular drugs.
• Revenue growth prospects are limited by maturity, but risk-adjusted returns depend on: (i) remaining U.S. exclusivity and patent barriers to generic entry, (ii) how the safety and label positioning support persistence versus switching, and (iii) whether competitors expand market share via mechanistic differentiation or rapid generic erosion outside key geographies.
• For investors, the near-to-mid term thesis is “patent runway plus channel durability,” not a blockbuster growth curve. The downside is a step-change in gross margin from generic entry if exclusivity thins faster than market durability offsets.

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What is ADEMPAS (riociguat) used for and what is its commercial profile?

Indications and label positioning

ADEMPAS (riociguat) is approved for pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH), including inoperable CTEPH and persistent/recurrent CTEPH after revascularization. The franchise’s commercial profile is built around:

• A defined, medically supervised patient population
• Chronic dosing with monitoring demands
• Strong reliance on specialist prescribing and treatment pathways (including combination therapy)

What drives utilization

Key utilization drivers in specialty PAH/CTEPH care typically include:

• Access to guideline-aligned sequencing for PAH and CTEPH patients
• Ability to maintain therapy after dose titration and tolerability outcomes
• Use of ADEMPAS in CTEPH settings where surgical options are limited or outcomes are residual

Where price and reimbursement matter most

In PAH/CTEPH, revenue outcomes track tightly to:

• Net pricing after rebates and state/federal payer mixes
• Prior authorization and step-edit constraints
• Specialty pharmacy channel economics

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What is the ADEMPAS patent estate in the U.S., and when does riociguat lose exclusivity?

Featured snippet answer: Investment case hinges on the last enforceable U.S. composition-of-matter and any formulation/process patents listed in the Orange Book for riociguat.

U.S. exclusivity architecture

For a small-molecule like riociguat, U.S. market exclusivity usually includes a mix of:

• Patent exclusivity (composition of matter is the primary barrier)
• Orange Book-listed exclusivity tied to branded NDA status
• Potential statutory exclusivity only if relevant to the NDA history (often earlier than current commercial life)

How to model the exclusivity “cliff”

For investors, the correct risk model is not a single date. It is a layered barrier stack:

1. Primary patent expiry for composition-of-matter
2. Secondary patents for formulations, particle size, polymorphs, salts, or manufacturing
3. Method-of-use and combination therapy patents (if any)
4. Potential Hatch-Waxman litigation and settlement-driven “workarounds” and entry dates

Generic entry risk framework

Market-entry timing depends on:

• Whether ANDA filers can design around formulation and method claims
• Whether Paragraph IV challenges trigger litigation stay periods
• Settlement agreements that may delay launch but can be factually limited by court outcomes

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What is the Orange Book status of ADEMPAS (riociguat) and which patents are listed for each dosage form?

How investors should read Orange Book entries

Orange Book listings provide the real-world map for generic entry risk. The durable view is:

• Dosage form specific patent coverage (tablets vs other presentations)
• Patent type (composition, formulation, method)
• Expiration and exclusivity date and whether patents are still “active” at the current point in time

What to look for in the riociguat listings

For an analyst-grade risk screen, parse:

• Active patents with the latest expiries
• Whether any formulation patents end after the composition-of-matter expiry
• Whether there are method-of-use patents likely to affect label-workalike or indication-scoped launches

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How strong is the patent estate for riociguat: composition, formulations, and manufacturing IP?

Composition-of-matter vs. defensive formulation patents

Investment relevance is in claim breadth:

• Composition-of-matter patents tend to be harder to work around for generic applicants.
• Formulation and manufacturing patents can create “entry friction” even when composition patents approach expiry, particularly if they cover:
  • specific crystal forms or polymorphs
  • stability and dissolution targets
  • excipient systems or coating approaches
  • manufacturing parameters that are difficult to replicate

Method-of-use patents and label-scoped risk

If method-of-use patents exist, generic timing can be affected by:

• Label carve-outs
• Indication-scoped launch strategies
• Physician usage patterns and whether enforcement would be practical

Practical investment conclusion

For a niche high-cost drug, a “good” patent estate often means:

• Multiple independently enforceable claims remaining
• Fewer entry pathways that avoid litigation
• Low likelihood of fast design-arounds

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Which companies are challenging ADEMPAS with Paragraph IV ANDAs, and what is the litigation timeline?

What matters for investment

Paragraph IV litigation affects:

• Likelihood of delayed launch
• Settlement terms (entry date, exclusivity buyouts)
• Court outcomes that can invalidate key claims

How to structure the risk register

A buildable risk register needs, for each challenger:

• Filing date and paragraph IV basis (if publicly available)
• Asserted patents
• Case docket number
• Key hearings and rulings
• Settlement date and entry terms (if any)

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What settlement agreements or consent decrees affect generic launch of riociguat?

Investment sensitivity

Settlements create near-term downside protection but can also introduce:

• Partial entry at an earlier date for some dosage strengths
• Design-around approvals
• Cross-licensing that reduces future leverage

For modeling, investors should treat settlement-backed dates as probabilistic, not deterministic, and align with:

• Remaining unasserted patents
• Whether the settlement covers all dosage forms
• Whether the settlement blocks all potential ANDA pathways or just the named filer(s)

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What generic entry risks exist for ADEMPAS and how would they show up in revenues?

Revenue impact mechanics

If generics enter:

• Branded pricing typically declines through rebate rework and payer contracting
• Volume may shift quickly to generics as clinicians comply with payer incentives
• Specialty channel distribution can accelerate switching due to acquisition cost pressure

How to forecast the downtrend

A robust approach uses:

• Step-change assumptions for net price erosion
• Timing assumptions by dosage form and strength
• Uptake curves driven by payer policies and formulary placement

Competitive posture beyond generics

Even without immediate generic entry, competitors can pressure:

• With alternative PAH/CTEPH therapies that shift sequencing
• Through payer formulary preferences
• Through patient access programs that offset higher acquisition costs for competing agents

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How does ADEMPAS compare with other PAH and CTEPH therapies in clinical positioning and competitive durability?

Mechanism and differentiation

Riociguat is a soluble guanylate cyclase stimulator. Competitive frameworks in PAH/CTEPH often cluster around:

• PDE5 inhibitors (cGMP pathway)
• Endothelin receptor antagonists
• Prostacyclin pathway agents
• Combination therapy strategies

Investment implications:

• Mechanistic differentiation can preserve some market share in patients previously stabilized on riociguat
• Switching risk rises as treatment guidelines evolve and payer coverage expands for lower-cost alternatives

Why persistence matters more than conversion

For niche drugs, revenue stability often relies on:

• Tolerability-based persistence after titration
• Low substitution when stable and reimbursed
• Physician comfort with long-term outcomes

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What FDA regulatory status does ADEMPAS have and what FDA changes could affect the franchise?

FDA pathway context

As a marketed NDA product, the key regulatory events for investment monitoring are:

• Label updates impacting contraindications, dosing, and safety warnings
• Safety communications that change prescribing behavior
• Updates affecting REMS (if applicable) or postmarketing commitments

Monitoring signals that drive commercial outcomes

In specialty cardiovascular and pulmonary vascular medicine, investors should track:

• Ongoing pharmacovigilance and labeling changes
• New clinical data that alters positioning
• Changes in guideline alignment that affect off-label or sequencing patterns

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What manufacturing and IP barriers exist for generic or biosimilar-style substitutes to riociguat?

No biosimilar pathway

Riociguat is a small molecule, so the competitive threat is ANDA, not a biosimilar.

Manufacturing complexity that can delay ANDA

Key barriers for small-molecule generics typically include:

• Solid-state form control (polymorphs, solvates, particle size distributions)
• Dissolution and bioavailability equivalence constraints
• Stability and shelf-life targets that increase batch-to-batch control requirements

Where generic risk is higher

Barriers are usually weaker when:

• Formulation patents are minimal
• There are fewer solid-state constraints
• The product is straightforward to replicate and equivalence can be demonstrated quickly

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Investment scenario: base, bull, and bear cases for ADEMPAS

Bear case: generic erosion accelerates

• Generic entry occurs at or near the last enforceable patent expiry or via settlement-accelerated launch.
• Net price compresses sharply and patient retention declines due to formulary switching.
• The franchise relies on incremental patient growth and persistence that cannot offset margin loss.

What investors would see

• Declining net sales despite stable patient counts
• Higher rebates and payer concentration stress
• Reduced gross margin and cash conversion volatility

Base case: delayed entry with durable channel retention

• Patent barriers hold through the modeled exclusivity runway.
• Branded channel retention is stable due to tolerability and physician familiarity.
• Growth is low to modest, but downside from price erosion is deferred.

What investors would see

• Sales stability with modest growth
• Continued payer and specialty pharmacy contracting strength
• Incremental cost pressure confined to specialty channel economics

Bull case: patent estate extension and sequencing advantages

• Enforcement delays generic entry past core expiry.
• Label positioning remains strong and supports continued line-of-therapy relevance.
• Competitive displacement is limited by patient persistence and combination therapy frameworks.

What investors would see

• Higher persistence, slower net price erosion
• Less aggressive payer substitution
• Potential for commercial improvement via improved access programs

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Key Takeaways

• ADEMPAS is a specialty pulmonary hypertension asset where investment value hinges on exclusivity duration, Orange Book-listed patent coverage, and Paragraph IV/litigation outcomes.
• Generic entry risk is the principal financial swing factor; the timing and scope by dosage form determine the magnitude and cadence of revenue erosion.
• The commercial upside is constrained by niche population size and treatment pathway competition, making persistence and reimbursement durability central to the thesis.
• Build a revenue risk model around the “patent barrier stack,” then overlay payer net price dynamics and switching curves.

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FAQs

1. What dosage forms of ADEMPAS are most exposed to generic substitution risk?
2. How do Paragraph IV ANDA settlements typically affect riociguat launch timing?
3. Which riociguat patent types (composition vs formulation vs method-of-use) create the highest design-around difficulty?
4. What labeling or safety updates for ADEMPAS most commonly shift prescribing behavior in PAH/CTEPH?
5. How should investors model net price erosion versus volume loss after riociguat generic entry?

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References

1. FDA. Orange Book: Approved Drug Products with Therapeutic Equivalence Evaluations. U.S. Food and Drug Administration. (Site accessed 2026-07-30).
2. FDA. Drug Label Information for ADEMPAS (riociguat). U.S. Food and Drug Administration. (Site accessed 2026-07-30).