RALTEGRAVIR POTASSIUM Drug Patent Profile

When do Raltegravir Potassium patents expire, and what generic alternatives are available?

Raltegravir Potassium is a drug marketed by Hetero Labs Ltd Iii and Lupin and is included in two NDAs.

The generic ingredient in RALTEGRAVIR POTASSIUM is raltegravir potassium. There is one drug master file entry for this compound. Five suppliers are listed for this compound. Additional details are available on the raltegravir potassium profile page.

DrugPatentWatch^® Litigation and Generic Entry Outlook for Raltegravir Potassium

A generic version of RALTEGRAVIR POTASSIUM was approved as raltegravir potassium by LUPIN on May 6^th, 2025.

Summary for RALTEGRAVIR POTASSIUM

US Patents:	0
Applicants:	2
NDAs:	2
Finished Product Suppliers / Packagers:	1
Raw Ingredient (Bulk) Api Vendors:	76
Clinical Trials:	5
Patent Applications:	404
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for RALTEGRAVIR POTASSIUM
DailyMed Link:	RALTEGRAVIR POTASSIUM at DailyMed

Recent Clinical Trials for RALTEGRAVIR POTASSIUM

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

Sponsor	Phase
St. James's Hospital, Ireland	Phase 4
Merck Sharp & Dohme Corp.	Phase 1/Phase 2
French National Institute for Health and Medical Research-French National Agency for Research on AIDS and Viral Hepatitis (Inserm-ANRS)	Phase 1/Phase 2

See all RALTEGRAVIR POTASSIUM clinical trials

Pharmacology for RALTEGRAVIR POTASSIUM

Drug Class	Human Immunodeficiency Virus Integrase Strand Transfer Inhibitor
Mechanism of Action	HIV Integrase Inhibitors

Medical Subject Heading (MeSH) Categories for RALTEGRAVIR POTASSIUM

Anti-HIV Agents

HIV Integrase Inhibitors

Anatomical Therapeutic Chemical (ATC) Classes for RALTEGRAVIR POTASSIUM

J05AJ	Integrase inhibitors
J05A	DIRECT ACTING ANTIVIRALS
J05	ANTIVIRALS FOR SYSTEMIC USE
J	Antiinfectives for systemic use

Paragraph IV (Patent) Challenges for RALTEGRAVIR POTASSIUM

Tradename	Dosage	Ingredient	Strength	NDA	ANDAs Submitted	Submissiondate
ISENTRESS HD	Tablets	raltegravir potassium	600 mg	022145	1	2022-10-21
ISENTRESS HD	Tablets	raltegravir potassium	400 mg	022145	1	2011-10-12

US Patents and Regulatory Information for RALTEGRAVIR POTASSIUM

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Hetero Labs Ltd Iii	RALTEGRAVIR POTASSIUM	raltegravir potassium	TABLET;ORAL	203540-001	Dec 19, 2024		DISCN	No	No
Lupin	RALTEGRAVIR POTASSIUM	raltegravir potassium	TABLET;ORAL	217990-001	May 6, 2025	AB	RX	No	No

Raltegravir Potassium Market Dynamics, Patent Exclusivity, and Financial Trajectory

Last updated: September 1, 2026

Raltegravir potassium is the active pharmaceutical ingredient in Merck's Isentress and Isentress HD HIV integrase strand transfer inhibitor products. The product has moved from premium branded therapy to a mature, price-sensitive market. Its commercial decline reflects competition from dolutegravir-, bictegravir-, and long-acting cabotegravir-based regimens, along with U.S. patent expiry and generic entry risk. The franchise retains clinical value in selected pediatric, neonatal, pregnancy, and treatment-experienced populations, but its long-term revenue ceiling is materially below its peak.

What is raltegravir potassium and how is it marketed?

Raltegravir potassium is the potassium salt of raltegravir, an HIV-1 integrase strand transfer inhibitor. It prevents integration of HIV DNA into the host genome and is used with other antiretroviral agents.

Merck markets two principal oral products:

Product	Formulation	Original FDA approval	Main commercial position
Isentress	Raltegravir 400 mg film-coated tablet, twice daily	October 2007	Original branded product
Isentress HD	Raltegravir 600 mg tablet, two tablets once daily	May 2017	Once-daily branded formulation
Isentress chewable tablets	Pediatric formulation	Subsequent supplemental approvals	Pediatric and weight-based dosing
Oral suspension	Pediatric formulation	Subsequent supplemental approvals	Infants and young children

The product is approved for treatment of HIV-1 infection in combination with other antiretroviral agents. The FDA label includes adult and pediatric use, with dosing determined by age, weight, formulation, and clinical circumstances.[1]

The active ingredient is generally described as raltegravir potassium in regulatory and pharmaceutical contexts. Commercial demand is driven by raltegravir, while generic manufacturers may market equivalent tablets under the nonproprietary name.

When did raltegravir potassium lose market exclusivity?

U.S. regulatory exclusivity ended years before the product's principal patent protection. Isentress received five-year new chemical entity exclusivity after its October 2007 approval. That exclusivity expired in 2012. Pediatric exclusivity can add six months to applicable protection periods, but it did not create a durable barrier to generic competition for the franchise.[2]

The principal composition-of-matter patent commonly associated with raltegravir was U.S. Patent No. 7,169,780. The patent was granted in January 2007 and had an expiration date in December 2022, subject to applicable patent-term adjustments and pediatric extensions. Related continuation and formulation patents extended portions of the commercial estate, but they did not recreate broad composition-of-matter exclusivity after the core patent period.

Key U.S. exclusivity timeline

Event	Date or period	Commercial effect
U.S. patent application priority	2001-2002 period	Established the core raltegravir estate
FDA approval of Isentress	October 12, 2007	Began U.S. commercial sales
Five-year NCE exclusivity	Through approximately October 2012	Blocked ANDA approval during the period
FDA approval of Isentress HD	May 2017	Added once-daily branded presentation
Core U.S. patent expiration	December 2022, subject to listed adjustments	Removed the principal composition patent barrier
Post-expiry market	2023 onward	Generic and institutional price pressure increased

Exact generic launch timing depends on the ANDA applicant's certification, litigation outcome, approval status, manufacturing readiness, and commercial strategy. Patent expiry alone does not guarantee immediate broad substitution.

What patents protect raltegravir potassium and Isentress?

The raltegravir patent estate has included composition, pharmaceutical composition, formulation, and method-of-use claims. The most commercially important protection was the early patent covering raltegravir and related diketo acid integrase inhibitor compounds.

Core patent categories

Patent category	Protected subject matter	Strategic relevance
Compound patents	Raltegravir and related chemical structures	Broadest protection and primary launch barrier
Salt and pharmaceutical composition patents	Raltegravir potassium and drug compositions	Supports product-specific protection
Dosage-form patents	Tablets, chewables, suspension, and dosage presentations	Can delay substitution for specific products
Method-of-use patents	HIV treatment and dosing methods	Usually narrower than composition patents
Pediatric-use patents	Pediatric dosing and formulations	Protect selected submarkets rather than the entire franchise
Manufacturing patents	Processes and intermediates	Can raise cost or create supply barriers without blocking all generic products

The FDA Orange Book is the principal U.S. source for identifying patents listed against approved Isentress products. Orange Book listings should be reviewed by product strength and dosage form because a patent listed for a 400 mg tablet may not apply identically to Isentress HD, chewable tablets, or oral suspension.[3]

The commercial strength of the remaining estate is narrower than the original estate. A generic applicant can challenge a listed patent through a Paragraph IV certification, design around formulation claims, or seek approval for a dosage form with fewer applicable patents.

What is the Orange Book status of Isentress and Isentress HD?

Isentress and Isentress HD are FDA-approved products with Orange Book-listed patents historically associated with raltegravir composition and product protection. The practical Orange Book risk has changed materially since the expiration of the core patents.

A current diligence review should distinguish four questions:

1. Whether a patent remains listed against the exact strength and dosage form.
2. Whether the patent has expired or received a patent-term adjustment.
3. Whether pediatric exclusivity extends the effective protection period.
4. Whether an applicant has filed a Paragraph IV certification and triggered litigation.

The principal patent expiration period means that the remaining Orange Book listings are more likely to affect specific formulations, uses, or presentations than the full raltegravir market. Generic tablets can enter without necessarily duplicating every branded formulation.

Which companies are challenging raltegravir potassium patents?

Raltegravir has been subject to the standard generic-drug challenge environment for mature small-molecule products. ANDA applicants may include large multinational generic companies and regional manufacturers. Publicly identified challenge activity can change as applications are filed, withdrawn, settled, transferred, or approved.

The principal legal routes are:

• Paragraph IV certification alleging that a listed patent is invalid, unenforceable, or not infringed.
• Paragraph III certification seeking approval after patent expiry.
• Section viii carve-outs for protected methods of use.
• ANDA approval after patent expiration without a successful patent challenge.
• Abbreviated new drug applications for tablets or other dosage forms that do not copy the full branded product profile.

Unlike biologics, raltegravir does not face a biosimilar pathway. It is a conventional small-molecule drug, so competitive entry occurs through the ANDA pathway rather than under the Biologics Price Competition and Innovation Act.

What generic entry risks exist for raltegravir potassium?

Generic entry risk is high in the United States because the core patent estate has reached or passed its principal expiration period and the product has an established reference-drug history.

Generic entry scenarios

Scenario	Timing profile	Market impact
Single generic entrant	After approval and commercial launch	Moderate initial price erosion
Multiple tablet entrants	Typically follows first approval	Rapid price competition and lower net sales
Authorized generic	Originator or licensee supplies equivalent product	Can reduce third-party generic share
Formulation-specific entry	Targets 400 mg tablets, HD tablets, or pediatric forms	Partial erosion by presentation
Institutional tender competition	Hospitals and public programs switch suppliers	Accelerates unit-price decline
Delayed launch	Approval exists but commercial supply is limited	Slower revenue erosion, often temporary

Raltegravir's generic substitution profile is weaker than a once-daily, high-volume maintenance product because many HIV regimens are selected as complete fixed-dose combinations. In a fixed-dose combination market, prescribers often choose a single-tablet regimen containing a different integrase inhibitor rather than assembling a regimen around standalone raltegravir.

Generic entry therefore affects two revenue pools differently:

• Standalone raltegravir tablets are directly exposed to ANDA substitution.
• Branded HIV regimens built around newer agents are exposed mainly through therapeutic competition rather than direct substitution.

How does raltegravir compare with dolutegravir, bictegravir, and cabotegravir?

Raltegravir remains clinically useful but has lost preferred-regimen status in many adult treatment settings.

Product class	Dosing and positioning	Competitive advantage over raltegravir
Raltegravir	Twice daily for standard formulation; once daily for Isentress HD	Long clinical history and established pediatric use
Dolutegravir	Once daily in many regimens	Higher resistance barrier and broad guideline use
Bictegravir	Once daily in a fixed-dose combination	Single-tablet convenience and strong efficacy
Cabotegravir	Long-acting injectable with rilpivirine	Avoids daily oral dosing for eligible patients
Elvitegravir	Usually used in fixed-dose combinations with pharmacokinetic boosting	Earlier-generation option with more interaction constraints

The U.S. Department of Health and Human Services guidelines generally favor regimens containing dolutegravir or bictegravir for most treatment-naive adults. Raltegravir has a lower genetic barrier to resistance than dolutegravir and bictegravir and requires more frequent dosing in its original formulation.[4]

Raltegravir retains a role where clinicians value:

• Extensive safety and pregnancy experience.
• Pediatric and neonatal dosing flexibility.
• Use in patients with selected drug-interaction constraints.
• Treatment-experienced regimens based on resistance testing.
• Clinical familiarity in hospitals and public-health programs.

The main competitive issue is not only price. It is regimen architecture. A standalone tablet must compete against complete or near-complete once-daily regimens that improve adherence and reduce prescribing complexity.

What is the financial trajectory of the Isentress franchise?

Isentress was once a major HIV product for Merck, with annual global sales above $1 billion during its peak commercial period. Revenue subsequently declined as newer integrase inhibitors gained share, fixed-dose combinations expanded, and patent protection weakened.

Merck's annual reporting has shown a prolonged downward trajectory for Isentress and Isentress HD sales. Public company disclosures have varied in whether they report Isentress as a separate line item or within broader product categories, so historical comparisons should use the same reporting basis.

Indicative commercial trajectory

Period	Financial direction	Primary driver
2007-2012	Rapid growth	New product adoption and limited competition
2013-2016	Mature high-revenue phase	Broad use in HIV treatment
2017-2019	Decline begins	Dolutegravir and fixed-dose combination competition
2020-2022	Continued erosion	Older product profile and approaching patent expiry
2023 onward	Steeper generic and price risk	Core patent expiry and mature-market substitution

Merck's Isentress sales peaked at more than $1 billion annually during the product's mature branded period. By the early 2020s, sales had declined substantially from that level as newer HIV products displaced raltegravir in first-line therapy. Merck's annual reports identify competition and lower demand as contributors to the decline.[5]

The most important financial variables are:

1. U.S. generic penetration.
2. Average selling price after patent expiry.
3. Volume retention in pediatric and treatment-experienced patients.
4. International procurement pricing.
5. Continued use of Isentress HD versus cheaper immediate-release alternatives.
6. Merck's ability to retain hospital, government, and public-health accounts.

The franchise's revenue profile is now closer to a mature specialty product than a growth asset. Gross margins are likely to contract faster than volumes once multiple generic suppliers qualify for substitution.

What FDA regulatory status affects raltegravir potassium demand?

Raltegravir has full FDA approval for HIV-1 treatment in combination with other antiretroviral drugs. Its regulatory profile is established, and the principal commercial question is no longer initial approval risk. It is lifecycle management and relevance within modern HIV guidelines.

Regulatory factors supporting continued demand include:

• Pediatric labeling across multiple age and weight groups.
• Established clinical data in pregnancy and pediatric populations.
• Multiple oral dosage forms.
• Long-term postmarketing experience.
• Inclusion in government treatment programs and institutional formularies.

Regulatory factors limiting growth include:

• No meaningful new-chemical-entity exclusivity remaining.
• No biological exclusivity framework.
• Lack of a new therapeutic indication comparable to the original HIV approval.
• Increasing preference for once-daily and single-tablet regimens.
• Limited commercial value from incremental formulation changes after broad patent expiry.

What manufacturing and intellectual-property barriers remain?

Manufacturing barriers are moderate rather than prohibitive. Raltegravir requires control of chemical intermediates, salt formation, particle properties, impurity profiles, dissolution, and tablet performance. These requirements can delay approval or reduce the number of qualified suppliers, but they do not create the same barrier as a complex biologic or sterile injectable.

The main generic development issues are:

• Reproducible synthesis of raltegravir and its intermediates.
• Control of the potassium salt and solid-state properties.
• Bioequivalence for immediate-release and high-dose formulations.
• Stability and dissolution performance.
• Pediatric dosage-form manufacturing.
• API supply concentration and quality-system compliance.

The patent estate may still matter for specific manufacturing routes or formulations. Process patents rarely preserve the entire commercial franchise when competing manufacturers can use alternative methods.

What licensing deals affect raltegravir potassium?

Raltegravir was developed and commercialized by Merck, with Merck retaining the central global commercial position under the Isentress brand. The product has not generated the licensing economics associated with co-developed biologics or partnered specialty drugs.

Potential commercial arrangements in mature markets are more likely to involve:

• Regional distribution agreements.
• Generic supply and authorized-generic arrangements.
• Public-health procurement contracts.
• API manufacturing relationships.
• Local regulatory commercialization rights.

The strategic value of a licensing transaction is therefore tied to manufacturing scale, geographic access, and supply reliability rather than discovery-stage innovation.

What geographic markets remain attractive?

The United States is the most exposed to patent expiry and generic substitution. Europe and other high-income markets face similar competitive pressure, although timing depends on national patent law, reimbursement policy, and generic penetration.

Emerging markets may retain demand because:

• Public-health programs prioritize low-cost antiretroviral access.
• Pediatric formulations remain clinically useful.
• Treatment protocols can differ from U.S. guideline preferences.
• Procurement contracts may favor established products with predictable supply.
• Generic manufacturing can support lower-cost distribution.

The commercial opportunity is volume-based rather than price-based. Suppliers with reliable API access, WHO-prequalified or nationally approved manufacturing, and government-tender capability may capture more value than companies relying on premium branded pricing.

What patent litigation and settlement issues affect market entry?

The key litigation risk historically centered on Paragraph IV challenges to Merck's Orange Book-listed patents. A Paragraph IV notice can trigger a 30-month stay of FDA approval if the patent holder files an infringement action within the statutory period.[6]

For a mature product such as raltegravir, settlement economics change over time:

• Before core patent expiry, a settlement may define an authorized launch date.
• Near expiry, litigation may focus on narrower formulation or method claims.
• After expiry, the commercial value of a broad settlement falls sharply.
• A settlement may still matter for a particular dosage form or geographic market.
• Manufacturing and supply covenants can become more important than launch-date restrictions.

Current case-specific conclusions require review of the latest Orange Book, FDA ANDA records, PACER or district-court filings, and settlement terms. The broad market conclusion is clear: the central composition-patent barrier is no longer a durable protection for the overall raltegravir market.

How strong is the raltegravir potassium patent estate?

The estate was strong at launch because it included early compound protection and supported a differentiated HIV product. Its current strength is moderate to weak for broad market exclusion.

Estate dimension	Current assessment
Core compound protection	Expired or at the end of its effective term
Formulation protection	Narrower and product-specific
Method-of-use protection	Limited ability to block all generic sales
Pediatric protection	Relevant to selected populations
Manufacturing protection	Possible cost or process barrier, not a complete market block
Litigation leverage	Reduced after core patent expiry
Generic exposure	High for standard oral tablets

Key Takeaways

• Raltegravir potassium is the active ingredient in Merck's Isentress and Isentress HD HIV products.
• The product's five-year NCE exclusivity ended in 2012.
• The principal U.S. composition patent reached its December 2022 expiration period, subject to applicable adjustments.
• Generic entry risk is high for standard raltegravir tablets.
• Raltegravir has lost share to dolutegravir, bictegravir, and long-acting cabotegravir.
• Clinical demand remains in pediatric, neonatal, pregnancy, treatment-experienced, and selected interaction-sensitive populations.
• The Isentress franchise has declined from peak annual sales above $1 billion.
• Future revenue is likely to depend on residual branded use, public-health procurement, pediatric demand, and generic manufacturing economics.
• Raltegravir is a small-molecule drug and is exposed to ANDA competition, not biosimilar competition.
• The remaining patent estate is more relevant to specific formulations and uses than to the entire raltegravir market.

FAQs about raltegravir potassium market and exclusivity

Is raltegravir potassium still a branded drug?

Yes. Merck continues to market raltegravir under the Isentress and Isentress HD brands, although the product operates in a mature market with generic substitution risk.

Can raltegravir potassium be substituted automatically at the pharmacy?

Substitution depends on FDA therapeutic-equivalence ratings, state pharmacy law, payer policy, product strength, and dosage form. A generic 400 mg tablet may not be interchangeable with every Isentress presentation.

Does raltegravir potassium have biosimilar competition?

No. Raltegravir is a chemically synthesized small molecule. Competition occurs through FDA ANDAs and generic-drug approvals.

Is Isentress HD protected separately from Isentress?

Isentress HD may have separate formulation, dosage, or product-specific patent listings. Those protections must be assessed against the exact Orange Book entry and expiration status.

Is raltegravir still used in HIV treatment guidelines?

Yes, but it is generally less preferred for routine adult first-line therapy than higher-barrier, once-daily integrase inhibitor regimens. Its continued use is concentrated in selected clinical and pediatric settings.

References

1. U.S. Food and Drug Administration. (2024). Isentress and Isentress HD prescribing information.
2. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book.
3. U.S. Food and Drug Administration. (2024). Orange Book patent and exclusivity information for Isentress products.
4. Panel on Antiretroviral Guidelines for Adults and Adolescents. (2024). Guidelines for the use of antiretroviral agents in adults and adolescents with HIV. U.S. Department of Health and Human Services.
5. Merck & Co., Inc. (2018-2024). Annual reports and Form 10-K filings.
6. U.S. Food and Drug Administration. (2023). Abbreviated new drug application approvals and patent certification procedures.