XERMELO Drug Patent Profile

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

Xermelo is a drug marketed by Tersera and is included in one NDA. There are five patents protecting this drug.

This drug has seventy patent family members in twenty-nine countries.

The generic ingredient in XERMELO is telotristat etiprate. One supplier is listed for this compound. Additional details are available on the telotristat etiprate profile page.

DrugPatentWatch^® Generic Entry Outlook for Xermelo

Xermelo was eligible for patent challenges on February 28, 2021.

By analyzing the patents and regulatory protections it appears that the earliest date for generic entry will be December 11, 2027. This may change due to patent challenges or generic licensing.

Indicators of Generic Entry

Summary for XERMELO

International Patents:	70
US Patents:	5
Applicants:	1
NDAs:	1
Finished Product Suppliers / Packagers:	1
Raw Ingredient (Bulk) Api Vendors:	56
Clinical Trials:	5
Patent Applications:	110
Drug Prices:	Drug price information for XERMELO
What excipients (inactive ingredients) are in XERMELO?	XERMELO excipients list
DailyMed Link:	XERMELO at DailyMed

See drug prices for XERMELO

DrugPatentWatch^® Estimated Loss of Exclusivity (LOE) Date for XERMELO

NDA:

208794

Dosage:

TABLET;ORAL

^*The generic entry opportunity date is the latter of the last compound-claiming patent and the last regulatory exclusivity protection. Many factors can influence early or later generic entry. This date is provided as a rough estimate of generic entry potential and should not be used as an independent source.

Recent Clinical Trials for XERMELO

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

Sponsor	Phase
Aman Chauhan	Phase 2
University of Chicago	Phase 2
Ipsen	Phase 3

See all XERMELO clinical trials

Pharmacology for XERMELO

Drug Class	Tryptophan Hydroxylase Inhibitor
Mechanism of Action	Tryptophan Hydroxylase Inhibitors

US Patents and Regulatory Information for XERMELO

XERMELO is protected by five US patents.

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

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Tersera	XERMELO	telotristat etiprate	TABLET;ORAL	208794-001	Feb 28, 2017		RX	Yes	Yes				Y
Tersera	XERMELO	telotristat etiprate	TABLET;ORAL	208794-001	Feb 28, 2017		RX	Yes	Yes				Y
Tersera	XERMELO	telotristat etiprate	TABLET;ORAL	208794-001	Feb 28, 2017		RX	Yes	Yes
Tersera	XERMELO	telotristat etiprate	TABLET;ORAL	208794-001	Feb 28, 2017		RX	Yes	Yes
Tersera	XERMELO	telotristat etiprate	TABLET;ORAL	208794-001	Feb 28, 2017		RX	Yes	Yes				Y

International Patents for XERMELO

When does loss-of-exclusivity occur for XERMELO?

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

Argentina

Australia

Brazil

Canada

Colombia

Denmark

Ecuador

Eurasian Patent Organization

European Patent Office

Hungary

Israel

Japan

Mexico

Netherlands

New Zealand

Norway

Poland

Portugal

South Africa

South Korea

Spain

Taiwan

Ukraine

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 XERMELO around the world.

Country	Patent Number	Title	Estimated Expiration
Argentina	064279
Australia	2007333120
Brazil	PI0720270
Canada	2672233
Colombia	6220855

Supplementary Protection Certificates for XERMELO

Patent Number	Supplementary Protection Certificate	SPC Country	SPC Expiration	SPC Description
2091940	CA 2018 00011	Denmark		PRODUCT NAME: TELOTRISTAT OR A PHARMACEUTICALLY ACCEPTABLE ESTER, OR A SALT THEREOF, INPARTICULAR TELOTRISTAT ETHYL, MORE PARTICULARLY HIPPURATE SALT OF TELOTRISTAT ETHYL; REG. NO/DATE: EU/1/17/1224 20170920
2091940	300929	Netherlands		DETAILS ASSIGNMENT: CHANGE OF OWNER(S), ASSIGNMENT
2091940	122018000025	Germany		PRODUCT NAME: TELOTRISTAT ODER EIN PHARMAZEUTISCH AKZEPTABLES SALZ ODER SOLVAT DAVON, EINSCHLIESSLICH TELOTRISTATETHYL; REGISTRATION NO/DATE: EU/1/17/1224 20170918
2091940	2018C/009	Belgium		DETAILS ASSIGNMENT: CHANGE OF OWNER(S), ASSIGNMENT
2091940	1890014-2	Sweden		PRODUCT NAME: TELOTRISTAT OR A PHARMACEUTICALLY ACCEPTABLE ESTER, OR A SALT THEREOF, IN PARTICULARLY TELOTRISTAT ETHYL, MORE PARTICULARLY HIPPURATE SALT OF TELOTRISTAT ETHYL; REG. NO/DATE: EU/1/17/1224 20170920

Last updated: July 27, 2026

Xermelo (telotristat etiprate): market dynamics and financial trajectory from launch through exclusivity, generic and biosimilar risk

Xermelo (telotristat ethyl/etiprate, anti-diarrheal for carcinoid syndrome) has been a niche revenue driver tied to the slow growth of diagnosed carcinoid syndrome with persistent diarrhea. The financial trajectory is constrained by (1) a limited and heterogeneous patient population, (2) competition from somatostatin analogs and targeted carcinoid therapies that can reduce diarrhea burden, and (3) a comparatively narrow label that does not support broad uptake outside carcinoid syndrome. Commercial scaling depends on oncology GI and NET center prescribing, payer coverage, and adherence to long-term use.

Market structure for carcinoid syndrome diarrhea: what determines uptake and revenue

Xermelo is positioned for persistent diarrhea in adult patients with carcinoid syndrome inadequately controlled by somatostatin analog therapy. That label architecture drives demand in distinct channels:

• Patient funnel is limited by incidence of neuroendocrine tumors with carcinoid syndrome, diagnostic practices, and documentation of “persistent diarrhea” despite somatostatin analogs.
• Prescribing clusters around NET centers, gastrointestinal oncology, and endocrinology practices that manage somatostatin analog regimens and diarrhea outcomes.
• Uptake is influenced by payer policies for “add-on” symptomatic therapies in oncology supportive care, with utilization management tied to prior somatostatin analog failure and symptom persistence.

Commercial levers that shift net sales for Xermelo

Revenue in this niche category tends to be dominated by:

• Rebate and patient assistance terms shaped by payer networks and formulary design.
• Treatment duration in practice, where diarrhea symptom control drives continuation while discontinuation occurs with diarrhea resolution, intolerance, or progression-driven changes in regimen.
• Sequencing behavior: if diarrhea improves after dose optimization or switching somatostatin analogs, the incremental contribution of telotristat is reduced.

Key market dynamic: “add-on” timing

Because the product is used after inadequate control on somatostatin analogs, the market dynamic is not first-line. It is a later-line add-on decision, so conversion rates from somatostatin analog users to telotristat users track real-world time-to-persistence of diarrhea and payer approval speed.

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How is Xermelo priced and reimbursed in the US: payer mix, formulary access, and net revenue drivers?

Xermelo pricing and net revenue are primarily governed by US managed care coverage, step edits, and prior authorization requirements that tie reimbursement to label-defined criteria.

What do typical payer controls for add-on carcinoid diarrhea look like?

For niche oncology-supportive agents, payer controls commonly include:

• Prior authorization requiring documentation of carcinoid syndrome and persistent diarrhea despite somatostatin analog therapy.
• Quantity limits tied to dosing schedule.
• Step-therapy or “must have tried” requirements for specific somatostatin analogs.
• Off-formulary status for plans without a carve-out for NET centers.

Why payer behavior matters more than gross list price

For a low-prevalence indication, net revenue is highly sensitive to:

• Number of covered lives in formulary plans.
• Rate of approvals for prior authorization.
• Rebate structure and contracting terms with pharmacy benefit managers.

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When does Xermelo lose exclusivity: patent and regulatory runway affecting long-term sales?

Long-term financial trajectory is driven by both regulatory exclusivity and the patent estate covering telotristat etiprate (drug substance, formulations, and methods of use for carcinoid syndrome diarrhea).

How exclusivity timing typically maps to sales decay in niche oncology supportive therapy

For specialty drugs with limited patient pools, generic pressure usually results in:

• Rapid share erosion after first credible launch, because prescriber switching can be swift when payers require lower-cost alternatives.
• Price resets through contracting and rebate pressure if payers add multiple competitors.

A precise exclusivity calendar requires Orange Book and patent-file-level mapping; without that, the financial narrative is limited to directional risk: the earlier the credible Paragraph IV or other challenge window, the earlier payer-led conversions begin.

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What generic entry risks exist for Xermelo: Paragraph IV, settlement terms, and launch scenarios?

Generic entry risk for a niche, oral specialty product is the central variable that determines the tail of the sales curve.

Common launch pathways that would change Xermelo’s financial trajectory

For a small patient population drug:

• A first generic (or first authorized generic) can capture most eligible demand due to payer formulary switching.
• A second entrant can drive additional rebate competition, further compressing net price.

How settlement and shared risk agreements typically affect timing

When settlement is reached in IP disputes, the near-term sales impact depends on:

• Date of permitted generic launch.
• Carve-outs that allow partial market entry earlier (for example, smaller strengths or narrower distribution channels).
• Authorized generic timing.

Without case-specific docket and settlement dates, only the market mechanism can be stated: sales generally hold until the first allowed entry date, then decline as pharmacy benefit design changes.

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What is the FDA and Orange Book status of Xermelo: list entries, exclusivity, and labeling constraints?

Xermelo’s FDA status determines both prescribing confidence and whether generic applicants can rely on approved labeling.

Orange Book listings that matter for financial exposure

For sales durability, the key Orange Book elements are:

• Patent coverage scope (drug substance vs formulation vs method of use).
• Patent expiration and any regulatory exclusivities that extend before patent expiry.

Label scope and commercial relevance

If the approved indication is narrow and treatment duration is patient-dependent, generic substitutions become more complex because:

• Physicians may avoid substitution when symptom control is stable and the patient has prior intolerance history.
• Payer policies may still enforce coverage criteria requiring “persistent diarrhea despite somatostatin analog therapy,” limiting eligible market conversion.

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How does Xermelo compare with competitors for carcinoid syndrome diarrhea: growth headroom vs displacement risk?

Xermelo competes indirectly with therapies used to control carcinoid syndrome symptoms, especially agents that reduce diarrhea burden.

Competitive set in practice

A realistic competitive set includes:

• Somatostatin analogs and dose optimization that can reduce diarrhea without telotristat.
• Other supportive symptom management strategies used in NET care.
• NET-directed therapies that can indirectly improve GI symptoms through tumor control.

Displacement risk depends on the treatment pathway

If real-world diarrhea control increasingly occurs via:

• Earlier NET-directed regimens, or
• More aggressive optimization of somatostatin analog therapy, then telotristat’s addressable conversion rate shrinks.

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What manufacturing or IP barriers affect Xermelo generic development: formulation, process, and stability?

For oral specialty drugs, the highest barriers are usually:

• Formulation patents covering composition and/or release characteristics.
• Process patents affecting particle size, stability, or manufacturing controls.

Generic development success also depends on:

• Ability to meet bioequivalence criteria across strengths and dosing frequency.
• Risk that formulation/process patents create design-around complexity.

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How strong is the patent estate for Xermelo: litigation intensity and potential weak links?

The strength of the patent estate is the direct driver of:

• Time until generic launch
• Probability that the first applicant’s launch is blocked or delayed

What to measure when evaluating strength

For a sales trajectory model, the patent estate strength indicators are:

• Number of Orange Book patents listed and how many are method-of-use vs composition/formulation.
• Court outcomes and whether injunctions or dismissals were sustained.
• Whether multiple distinct patents cover the same commercial use, raising the chance that at least one blocks launch.

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What Xermelo revenue exposure exists in major regions: US dependence and international coverage?

Financial trajectory for specialty drugs with narrow indications is typically US-weighted due to:

• Faster contracting and specialty pharmacy reach.
• Higher likelihood of inclusion in NET center formularies.

International revenue can add stability if:

• National reimbursement is aligned to label criteria.
• Pricing is supported by cost-effectiveness arguments for symptom control.

A full geographic quantification requires country-by-country sales reporting or payer data, which is not provided here.

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Key Takeaways

• Xermelo’s market is structurally constrained by the narrow carcinoid syndrome persistent diarrhea population and “add-on after somatostatin analog failure” use case.
• Net sales sensitivity is high to formulary access, prior authorization success, rebate contracting, and real-world persistence of diarrhea long enough to sustain long-term telotristat use.
• The main upside lever is NET center adoption and payer-approved continuity; the main downside lever is payer-driven substitution once credible generic entry is permitted.
• Long-run financial trajectory is dominated by the timing and strength of the Orange Book patent estate and any litigation or settlement dates that enable an earlier or delayed generic launch.
• Competitive displacement is indirect, via somatostatin analog optimization and tumor-directed therapies that reduce diarrhea burden.

FAQs

1. How does payer prior authorization for Xermelo typically impact prescription fill rates?
2. What patient selection criteria most strongly predict telotristat continuation in real-world carcinoid syndrome care?
3. How do rebate and contract terms usually change around the first generic filing window for niche oncology-supportive drugs?
4. What label elements most affect generic applicants’ ability to rely on approved use for Xermelo?
5. How do NET-directed therapies influence the incremental demand for add-on diarrhea control like telotristat?

References

1. FDA Orange Book. “Xermelo (telotristat ethyl/etiprate)” (product listings and patent entries). US Food and Drug Administration.
2. FDA Labeling. “Xermelo Prescribing Information.” US Food and Drug Administration.
3. Published clinical trial and regulatory summaries for telotristat (carcinoid syndrome diarrhea). FDA review documents and peer-reviewed publications.

DrugChatter Q&A for XERMELO

How does Xermelo treat carcinoid syndrome?