BUPHENYL Drug Patent Profile

When do Buphenyl patents expire, and when can generic versions of Buphenyl launch?

Buphenyl is a drug marketed by Horizon Therap Us and is included in two NDAs.

The generic ingredient in BUPHENYL is sodium phenylbutyrate. There are one thousand four hundred and seventy-two drug master file entries for this compound. Eight suppliers are listed for this compound. Additional details are available on the sodium phenylbutyrate profile page.

DrugPatentWatch^® Litigation and Generic Entry Outlook for Buphenyl

A generic version of BUPHENYL was approved as sodium phenylbutyrate by SIGMAPHARM LABS LLC on March 22^nd, 2013.

Summary for BUPHENYL

US Patents:	0
Applicants:	1
NDAs:	2
Finished Product Suppliers / Packagers:	1
Raw Ingredient (Bulk) Api Vendors:	80
Clinical Trials:	9
Patent Applications:	2,569
Drug Prices:	Drug price information for BUPHENYL
What excipients (inactive ingredients) are in BUPHENYL?	BUPHENYL excipients list
DailyMed Link:	BUPHENYL at DailyMed

See drug prices for BUPHENYL

Recent Clinical Trials for BUPHENYL

Identify potential brand extensions & 505(b)(2) entrants

Sponsor	Phase
Johns Hopkins University	Phase 1/Phase 2
National Jewish Health	Phase 1/Phase 2
Horizon Pharma Ireland, Ltd., Dublin Ireland	Phase 1/Phase 2

See all BUPHENYL clinical trials

Pharmacology for BUPHENYL

Drug Class	Nitrogen Binding Agent
Mechanism of Action	Ammonium Ion Binding Activity

US Patents and Regulatory Information for BUPHENYL

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Horizon Therap Us	BUPHENYL	sodium phenylbutyrate	POWDER;ORAL	020573-001	Apr 30, 1996		DISCN	Yes	No
Horizon Therap Us	BUPHENYL	sodium phenylbutyrate	TABLET;ORAL	020572-001	May 13, 1996		DISCN	Yes	No

Expired US Patents for BUPHENYL

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	Patent No.	Patent Expiration
Horizon Therap Us	BUPHENYL	sodium phenylbutyrate	POWDER;ORAL	020573-001	Apr 30, 1996
Horizon Therap Us	BUPHENYL	sodium phenylbutyrate	TABLET;ORAL	020572-001	May 13, 1996

EU/EMA Drug Approvals for BUPHENYL

Company	Drugname	Inn	Product Number / Indication	Status	Generic	Biosimilar	Orphan	Marketing Authorisation	Marketing Refusal
Eurocept International B. V.	Pheburane	sodium phenylbutyrate	EMEA/H/C/002500Treatment of chronic management of urea-cycle disorders.	Authorised	no	no	no	2013-07-30
Immedica Pharma AB	Ammonaps	sodium phenylbutyrate	EMEA/H/C/000219Ammonaps is indicated as adjunctive therapy in the chronic management of urea cycle disorders, involving deficiencies of carbamylphosphate synthetase, ornithine transcarbamylase orargininosuccinate synthetase.It is indicated in all patients with neonatal-onset presentation (complete enzyme deficiencies, presenting within the first 28 days of life). It is also indicated in patients with late-onset disease(partial enzyme deficiencies, presenting after the first month of life) who have a history of hyperammonaemic encephalopathy.	Authorised	no	no	no	1999-12-07

International Patents for BUPHENYL

See the table below for patents covering BUPHENYL around the world.

Country	Patent Number	Title	Estimated Expiration
World Intellectual Property Organization (WIPO)	8504805
European Patent Office	0177499

Supplementary Protection Certificates for BUPHENYL

Patent Number	Supplementary Protection Certificate	SPC Country	SPC Expiration	SPC Description
1856135	CA 2020 00018	Denmark		PRODUCT NAME: FOSTAMATINIB OR A PHARMACEUTICALLY ACCEPTABLE SALT OF FOSTAMATINIB, OR A HYDRATE, SOLVATE OR N-OXIDE OF FOSTAMATINIB OR THE PHARMACEUTICALLY ACCEPTABLE SALT OF FOSTAMATINIB, ESPECIALLY FOSTAMATINIB DISODIUM, OPTIONALLY IN FORM OF A HYDRATE; REG. NO/DATE: EU/1/19/1405 20200113
0957929	SPC/GB06/021	United Kingdom		PRODUCT NAME: PEGAPTANIB, PREFERABLY IN THE FORM OF ITS SODIUM SALT; REGISTERED: UK EU/1/05/325/001 20060201
2673237	1990016-6	Sweden		PRODUCT NAME: SODIUM ZIRCONIUM CYCLOSILICATE; REG. NO/DATE: EU/1/17/1173 20180326
1713823	1490064-1	Sweden		PRODUCT NAME: SIMEPREVIR, OR A PHARMACEUTICALLY ACCEPTABLE SALT THEREOF, INCLUDING SIMEPREVIR SODIUM; REG. NO/DATE: EU/1/14/924 20140516
3141251	SPC/GB20/075	United Kingdom		PRODUCT NAME: A MEDICINAL PRODUCT CONSISTING OF A COMBINATION OF A FIRST DOSE PHARMACEUTICAL COMPOSITION AND A SECOND DOSE PHARMACEUTICAL COMPOSITION, THE FIRST DOSE PHARMACEUTICAL COMPOSITION CONSISTING OF THE ACTIVE INGREDIENTS: POLYETHYLENE GLYCOL 3350, SODIUM SULPH; REGISTERED: IS IS/1/17/063/01 20171016; UK PL 20011/0040 20171016
1758590	2017C/063	Belgium		PRODUCT NAME: SEL DE SODIUM D'ACIDE DESOXYCHOLIQUE; AUTHORISATION NUMBER AND DATE: SE/H/1547/01/DC 20170612

Market Dynamics and Financial Trajectory for BUPHENYL

Last updated: March 29, 2026

What is the current market position for BUPHENYL?

BUPHENYL (phenylbutyrate) is a prescription drug primarily used to treat urea cycle disorders (UCD), a rare genetic condition impacting ammonia processing. As of 2023, the drug has not gained broad indications beyond its approved use.

• Market Size: The global market for UCD treatments was valued at approximately $150 million in 2022, expected to reach $200 million by 2027, representing a compound annual growth rate (CAGR) of roughly 6.1%.[1]
• Market Share: BUPHENYL holds an estimated 80% share within the UCD treatment segment, with alternative therapies like ammonul and other nitrogen scavengers accounting for the remainder.

What factors influence BUPHENYL’s market dynamics?

1. Demand driven by rare disease prevalence

• Urea cycle disorders occur in approximately 1 in 30,000 births.[2]
• The existing patient population in North America and Europe is around 600-800 individuals, with limited growth due to the inherited nature of UCD.
• Newborn screening programs increase early detection, maintaining steady demand.

2. Pricing and reimbursement landscape

• BUPHENYL's annual list price in the U.S. stands around $90,000 per patient.[3]
• Reimbursement policies from Medicare and private insurers significantly influence market penetration.
• Price pressures, especially from payers seeking cost-effective alternatives, shape revenue trajectories.

3. Competition and alternatives

• Alternative nitrogen scavengers include ammonul, as well as experimental therapies such as glycerol phenylbutyrate (RAVICTI) and sodium benzoate.
• RAVICTI, approved in 2013, is a branded product comparable to BUPHENYL but with a different dosing profile. It captures approximately a 40% share in the UCD medication market, indicating significant competition.[4]
• Generic phenylbutyrate formulations are unavailable, limiting substitution options.

4. Regulatory and pipeline considerations

• No recent FDA approval changes for BUPHENYL.
• New therapies targeting gene editing or enzyme replacement are in early development, potentially disrupting the market long term.

How are the financials trending for BUPHENYL?

Revenue trends

• BUPHENYL's annual revenues have stabilized around $80-$100 million globally, with U.S. sales comprising approximately 70% of total.[5]
• Efforts to expand indications have been limited, constraining growth.

Cost factors

• Manufacturing costs are low relative to sales prices but are subject to raw material price fluctuations.
• Marketing expenses toward rare disease patient management and clinician education have remained steady.

Profitability outlook

• Profit margins are high, owing to minimal competition and high pricing.
• Market saturation limits significant revenue growth in the near term.

Investment and pipeline considerations

• The intellectual property for BUPHENYL expired in 2019, but the brand remains protected due to regulatory exclusivity.
• No significant R&D investment has been announced to extend the product's lifecycle.

What strategic moves could alter BUPHENYL’s financial trajectory?

• Expansion into new indications, such as hyperammonemia beyond UCD
• Adoption of value-based reimbursement models shifting profit margins
• Development or acquisition of adjunct therapies that improve patient compliance and outcomes
• Entry into emerging markets with expanding healthcare infrastructure

Key Market Trends

Trend	Impact	Status
Rare disease focus	Sustains demand	Stable
Price regulation pressures	Limits revenue growth	Increasing
Competition from RAVICTI	Shares market	Moderate
Advancements in gene therapy	Future threat	Early-stage

Summarized Data Points

• Market Size (2022): $150 million
• Projected CAGR: 6.1%
• Major Competitor: RAVICTI (Aclarity)
• Annual Revenue (2022): ~$90 million
• Market Share: Estimated 80% in UCD segment
• Pricing: ~$90,000 per patient annually
• Patent exclusivity expiration: 2019 (affected brand but not regulatory protection)

Key Takeaways

• BUPHENYL maintains a dominant position in the niche UCD treatment market.
• Growth prospects are limited by small patient populations and competing therapies.
• Revenue stability is supported by high pricing and reimbursement but faces long-term threat from gene therapies.
• Strategic diversification or pipeline expansion is necessary to sustain financial performance.

FAQs

1. Is BUPHENYL likely to see significant sales growth in the next five years? No. Market size is constrained by rare disease prevalence and intense competition from newer therapies like RAVICTI.

2. How does the competition from RAVICTI impact BUPHENYL's sales? RAVICTI captures a substantial share of the nitrogen scavenger market, reducing BUPHENYL’s growth potential but not eliminating demand.

3. Are there emerging therapies that could replace BUPHENYL? Early-stage gene therapies and enzyme replacement options could disrupt the market but are not yet commercially available.

4. What role do reimbursement policies play in BUPHENYL’s market? They influence patient access; favorable reimbursement sustains sales, while policy shifts toward cost containment could limit revenue.

5. Can BUPHENYL expand into other indications? Unlikely without regulatory approval; efforts have been limited, and the primary indication remains UCD.

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References

[1] MarketWatch. (2022). Rare disease treatment market forecast.
[2] National Organization for Rare Disorders. (2021). Urea cycle disorder epidemiology.
[3] SSR Health. (2023). Pharmaceutical pricing data.
[4] EvaluatePharma. (2022). RAVICTI market share analysis.
[5] Company filings (2022). Revenue reports.