Letermovir - Generic Drug Details

What are the generic sources for letermovir and what is the scope of freedom to operate?

Letermovir is the generic ingredient in one branded drug marketed by MSD and Merck Sharp Dohme, and is included in three NDAs. There are two patents protecting this compound. Additional information is available in the individual branded drug profile pages.

Letermovir has ninety-eight patent family members in forty-eight countries.

One supplier is listed for this compound. There is one tentative approval for this compound.

Summary for letermovir

International Patents:	98
US Patents:	2
Tradenames:	1
Applicants:	2
NDAs:	3
Finished Product Suppliers / Packagers:	1
Raw Ingredient (Bulk) Api Vendors:	62
Clinical Trials:	41
Patent Applications:	955
What excipients (inactive ingredients) are in letermovir?	letermovir excipients list
DailyMed Link:	letermovir at DailyMed

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

Constraining patent/regulatory exclusivity:

10,603,384

Dosage:

SOLUTION;INTRAVENOUS

Constraining patent/regulatory exclusivity:

PROPHYLAXIS OF CYTOMEGALOVIRUS (CMV) DISEASE IN PEDIATRIC PATIENTS 12 YEARS OF AGE AND OLDER AND WEIGHING AT LEAST 40 KG WHO ARE KIDNEY TRANSPLANT RECIPIENTS AT HIGH RISK (DONOR CMV SEROPOSITIVE/RECIPIENT CMV SERONEGATIVE [D+/R-])

Dosage:

TABLET;ORAL

Constraining patent/regulatory exclusivity:

PROPHYLAXIS OF CYTOMEGALOVIRUS (CMV) DISEASE IN PEDIATRIC PATIENTS 12 YEARS OF AGE AND OLDER AND WEIGHING AT LEAST 40 KG WHO ARE KIDNEY TRANSPLANT RECIPIENTS AT HIGH RISK (DONOR CMV SEROPOSITIVE/RECIPIENT CMV SERONEGATIVE [D+/R-])

Dosage:

PELLETS;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 letermovir

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

Sponsor	Phase
City of Hope Medical Center	PHASE1
National Cancer Institute (NCI)	PHASE1
Cornell University	PHASE2

See all letermovir clinical trials

Generic filers with tentative approvals for LETERMOVIR

Applicant	Application No.	Strength	Dosage Form
		480MG	TABLET;ORAL
		240MG	TABLET;ORAL

The 'tentative' approval signifies that the product meets all FDA standards for marketing, and, but for the patents / regulatory protections, it would approved.

Pharmacology for letermovir

Drug Class	Cytomegalovirus DNA Terminase Complex Inhibitor
Mechanism of Action	Cytochrome P450 2C19 Inducers Cytochrome P450 2C8 Inhibitors Cytochrome P450 2C9 Inducers Cytochrome P450 3A Inhibitors DNA Terminase Complex Inhibitors Organic Anion Transporting Polypeptide 1B1 Inhibitors Organic Anion Transporting Polypeptide 1B3 Inhibitors

Anatomical Therapeutic Chemical (ATC) Classes for letermovir

J05AX	Other antivirals
J05A	DIRECT ACTING ANTIVIRALS
J05	ANTIVIRALS FOR SYSTEMIC USE
J	Antiinfectives for systemic use

US Patents and Regulatory Information for letermovir

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Msd	PREVYMIS	letermovir	PELLETS;ORAL	219104-002	Aug 30, 2024		RX	Yes	Yes	RE46791		Y	Y
Merck Sharp Dohme	PREVYMIS	letermovir	SOLUTION;INTRAVENOUS	209940-002	Nov 8, 2017		RX	Yes	Yes
Merck Sharp Dohme	PREVYMIS	letermovir	TABLET;ORAL	209939-002	Nov 8, 2017		RX	Yes	Yes	RE46791		Y	Y
Msd	PREVYMIS	letermovir	PELLETS;ORAL	219104-001	Aug 30, 2024		RX	Yes	No
Merck Sharp Dohme	PREVYMIS	letermovir	TABLET;ORAL	209939-001	Nov 8, 2017		RX	Yes	No
Msd	PREVYMIS	letermovir	PELLETS;ORAL	219104-002	Aug 30, 2024		RX	Yes	Yes
Merck Sharp Dohme	PREVYMIS	letermovir	TABLET;ORAL	209939-001	Nov 8, 2017		RX	Yes	No	RE46791		Y	Y

Expired US Patents for letermovir

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	Patent No.	Patent Expiration
Merck Sharp Dohme	PREVYMIS	letermovir	SOLUTION;INTRAVENOUS	209940-002	Nov 8, 2017	7,196,086
Merck Sharp Dohme	PREVYMIS	letermovir	TABLET;ORAL	209939-002	Nov 8, 2017	7,196,086
Merck Sharp Dohme	PREVYMIS	letermovir	TABLET;ORAL	209939-001	Nov 8, 2017	8,513,255
Merck Sharp Dohme	PREVYMIS	letermovir	TABLET;ORAL	209939-001	Nov 8, 2017	7,196,086
Merck Sharp Dohme	PREVYMIS	letermovir	SOLUTION;INTRAVENOUS	209940-001	Nov 8, 2017	7,196,086
Merck Sharp Dohme	PREVYMIS	letermovir	SOLUTION;INTRAVENOUS	209940-002	Nov 8, 2017	8,513,255
Merck Sharp Dohme	PREVYMIS	letermovir	TABLET;ORAL	209939-002	Nov 8, 2017	8,513,255

EU/EMA Drug Approvals for letermovir

Company	Drugname	Inn	Product Number / Indication	Status	Generic	Biosimilar	Orphan	Marketing Authorisation	Marketing Refusal
Merck Sharp & Dohme B.V.	Prevymis	letermovir	EMEA/H/C/004536Prevymis is indicated for prophylaxis of cytomegalovirus (CMV) reactivation and disease in adult CMV-seropositive recipients [R+] of an allogeneic haematopoietic stem cell transplant (HSCT).Consideration should be given to official guidance on the appropriate use of antiviral agents.	Authorised	no	no	yes	2018-01-08

International Patents for letermovir

Country	Patent Number	Title	Estimated Expiration
Serbia	59157	FARMACEUTSKI PREPARAT KOJI OBUHVATA ANTIVIRUSNO EFIKASAN DERIVAT DIHIDROHINAZOLINA (PHARMACEUTICAL PREPARATION COMPRISING AN ANTIVIRAL DIHYDROQUINAZOLINE DERIVATIVE)
Mexico	PA05011707	DIHIDROQUINAZOLINAS SUSTITUIDAS CON PROPIEDADES ANTIVIRALES. (SUBSTITUTED DIHYDROCHINAZOLINES HAVING ANTIVIRAL PROPERTIES.)
Portugal	1622880
Spain	2741698
Denmark	1622880
Slovenia	3556350
Japan	6387486

Supplementary Protection Certificates for letermovir

Patent Number	Supplementary Protection Certificate	SPC Country	SPC Expiration	SPC Description
1622880	2018C/025	Belgium		PRODUCT NAME: LETERMOVIR, DESGEWENST IN DE VORM VAN EEN ZOUT OF SOLVAAT ERVAN OF EEN SOLVAAT VAN EEN ZOUT; AUTHORISATION NUMBER AND DATE: EU/1 /1 7/1245 20170110
1622880	LUC00070	Luxembourg		PRODUCT NAME: LETERMOVIR; AUTHORISATION NUMBER AND DATE: EU71/17/1245 20180110
1622880	C201830035	Spain		PRODUCT NAME: LETERMOVIR, SUS SALES Y SOLVATOS, Y SOLVATOS DE LAS SALES DEL MISMO; NATIONAL AUTHORISATION NUMBER: EU/1/17/1245; DATE OF AUTHORISATION: 20180108; NUMBER OF FIRST AUTHORISATION IN EUROPEAN ECONOMIC AREA (EEA): EU/1/17/1245; DATE OF FIRST AUTHORISATION IN EEA: 20180108
1622880	2018C/015	Belgium		PRODUCT NAME: LETERMOVIR; AUTHORISATION NUMBER AND DATE: EU/1/17/1245 20180110
1622880	C 2018 027	Romania		PRODUCT NAME: LETERMOVIR SAU SAREA SA, SOLVATUL SAU, SAU SOLVATUL SARII SALE; NATIONAL AUTHORISATIONNUMBER: EU/1/17/1245; DATE OF NATIONAL AUTHORISATION: 20180108; NUMBER OF FIRST AUTHORISATION IN EU ROPEAN ECONOMIC AREA (EEA): EU/1/17/1245; DATE OF FIRST AUTHORISATION IN EEA: 20180108
1622880	C01622880/01	Switzerland		FORMER OWNER: AICURIS ANTI-INFECTIVE CURES GMBH, DE
1622880	2018/026	Ireland		PRODUCT NAME: LETERMOVIR, OR ITS SALT, SOLVATE, OR SOLVATE OF ITS SALT.; REGISTRATION NO/DATE: EU/1/17/1245 20180108

Market Dynamics and Financial Trajectory for Letermovir: An In-Depth Analysis

Last updated: November 14, 2025

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Introduction

Letermovir, marketed under the brand name Prevymis, is a groundbreaking antiviral drug developed by Merck & Co., primarily approved for the prevention of cytomegalovirus (CMV) infections in hematopoietic stem cell transplant (HSCT) recipients. Since its FDA approval in 2017, Letermovir has distinctly influenced clinical practices, spurred competitive strategies within the antiviral pipeline, and altered financial forecasts across the pharmaceutical landscape.

This comprehensive examination evaluates the current market dynamics and projects the financial trajectory for Letermovir, considering regulatory developments, clinical utilization, competitive pressures, and future market opportunities. The insights aim to assist stakeholders, including investors, pharmaceutical strategists, and healthcare providers, in making informed decisions within this evolving domain.

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Market Overview and Clinical Context

Prevalence of CMV and Clinical Need

Cytomegalovirus reactivation poses significant morbidity and mortality risks for immunocompromised patients, especially HSCT recipients and solid organ transplant recipients. The incidence of CMV infection remains high despite advances in transplantation medicine, with estimates suggesting symptomatic CMV reactivation in approximately 50-80% of HSCT patients without prophylaxis [1].

Traditional antivirals like ganciclovir, valganciclovir, and foscarnet have limitations, including toxicity, drug resistance, and complicated administration protocols. There exists a pressing need for safer, more effective prophylactic options with better compliance profiles—an unmet clinical need that Letermovir aims to fulfill.

Regulatory Milestones and Expansion

Following its initial approval in the United States in 2017, Letermovir has secured regulatory clearances across multiple regions. Notably, the European Medicines Agency (EMA) approved it in 2018 [2], and subsequent approvals extended indications to include prophylaxis in diverse populations. The drug’s favorable safety profile and oral formulation have supported its integration into transplant protocols.

Market Penetration and Adoption

Initially launched as a niche prophylactic agent in high-risk HSCT settings, Letermovir's adoption grew steadily owing to clinical guidelines embracing its efficacy and safety. However, uptake has faced obstacles primarily attributable to cost considerations, clinician familiarity with existing agents, and regional differences in healthcare infrastructure.

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Market Dynamics Influencing Letermovir

1. Competitive Landscape

While Letermovir holds a patent exclusivity period—originally until 2034—it operates amid competing antiviral agents and emerging therapies:

• Existing antivirals: Ganciclovir and valganciclovir remain first-line for CMV, especially in treatment rather than prophylaxis. Their widespread availability and familiarity sustain their dominance.
• Novel agents: Research into CMV-specific immunotherapeutics, innovative antivirals, and vaccine strategies pose future competitive threats, potentially eroding the market share of Letermovir [3].

2. Price and Reimbursement Strategies

Pricing remains a critical factor. Merck's initial pricing strategy positioned Prevymis as superior in safety and efficacy but faced resistance due to high costs relative to older generics. Payer negotiations, formulary placements, and regional reimbursement policies significantly influence adoption rates.

3. Clinical Guidelines and Physician Adoption

The integration of Letermovir into clinical guidelines—such as those by the American Society for Transplantation and Cellular Therapy (ASTCT) and European Society for Blood and Marrow Transplantation (EBMT)—has bolstered its credibility. However, variability in guideline updates and clinician familiarity can delay widespread adoption.

4. Regional Market Variations

Developed markets, notably North America and Europe, display higher adoption rates driven by advanced healthcare infrastructure, robust payer systems, and proactive transplant centers. Emerging markets face challenges in access, cost, and regulatory approval, tempering growth projections.

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Financial Trajectory Forecast

Current Revenue Landscape

Merck’s 2022 fiscal reports indicated that Letermovir generated approximately $900 million globally, reflecting rapid growth from its 2017 launch [4]. North American sales constitute over 60% of total revenue, with Europe representing a substantial minority. The relatively high penetrance in HSCT centers and proven clinical benefit sustain strong revenue streams.

Projected Growth Factors

• Market Expansion: Anticipated licensing extensions to prophylaxis in solid organ transplantation and other immunocompromised populations could unlock new revenue segments.
• Pipeline Developments: Ongoing clinical trials examining Letermovir's utility in broader antiviral indications, such as treatment rather than prophylaxis, suggest potential upside.
• Pricing Strategies: Negotiations for price reductions in certain markets and inclusion in formularies will influence revenue scalability.
• Market Penetration Challenges: Competition from biosimilars, generics, or new mechanisms could temper growth prospects.

Forecast Model and Key Trends

A conservative projection estimates that Letermovir’s revenue will reach $1.2 billion by 2025, driven by steady adoption in existing indications and emerging territory expansion. High gross margins are expected, contingent upon manufacturing efficiencies and negotiated reimbursement terms.

However, the market’s competitive and regulatory uncertainties could introduce volatility. If upcoming clinical data or competitor innovations reduce the perceived edge of Letermovir, revenues may see modest declines or plateau.

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Market Challenges and Opportunities

Challenges

• Price Sensitivity: High drug costs in certain healthcare systems limit cost-effectiveness perceptions.
• Competition: Emergence of prophylactic or curative therapies for CMV may displace Letermovir.
• Regulatory Hurdles: Delays or restrictions in geographical approvals curtail market reach.
• Resistance: The potential development of CMV resistance warrants vigilant monitoring and could impact long-term utility.

Opportunities

• Expansion into Solid Organ Transplantation: Pivotal trial results demonstrating efficacy could position Letermovir as a standard prophylactic in other transplantation fields.
• Combination Therapies: Combining Letermovir with immunotherapies or other antivirals could enhance efficacy.
• Biomarker-Driven Personalization: Tailoring prophylaxis based on predictive markers may optimize usage and reimbursement prospects.
• Global Access Programs: Strategic initiatives in emerging markets can broaden patient access and revenue.

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Conclusion

Letermovir's trajectory delineates a successful clinical innovation transforming CMV prophylaxis in transplant medicine. Its market dynamics hinge on strategic positioning within competitive, regulatory, and economic landscapes. The forecast indicates a strong growth trajectory over the next several years, underpinned by ongoing clinical research, expanding indications, and industry collaborations.

Nonetheless, uncertainties related to pricing, resistance, and emerging therapies necessitate agile strategic responses. Stakeholders investing in or leveraging Letermovir must continually monitor clinical and policy developments to optimize financial returns while improving patient outcomes.

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Key Takeaways

• Market penetration remains robust due to its safety profile and clinical efficacy, with projections indicating continued revenue growth toward $1.2 billion by 2025.
• Competitive factors, notably from existing antivirals and emerging therapies, will shape future market share.
• Pricing strategies and reimbursement negotiations are central to maximizing revenue potential across diverse healthcare systems.
• Regional variation in adoption underscores the importance of tailored market entry and expansion strategies.
• Strategic diversification, such as exploring new indications and combination therapies, offers avenues for sustainable growth.

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FAQs

1. Will Letermovir’s market share decline with the emergence of new antiviral therapies?
Potentially. While current data favor Letermovir’s safety and efficacy, competition from novel agents and approaches—like CMV vaccines or immunotherapies—could challenge its dominance. Continued clinical validation and strategic positioning are essential.

2. What are the main barriers to global market expansion of Letermovir?
Regulatory approvals, high pricing, reimbursement policies, and infrastructural limitations in emerging markets constitute primary barriers. Addressing these requires region-specific strategies and collaborations.

3. How does resistance development impact the long-term outlook of Letermovir?
Although resistance remains relatively rare, it can compromise efficacy and necessitate alternative therapies. Ongoing surveillance and combination approaches are critical to mitigate this risk.

4. Could generic versions of Letermovir appear soon?
Given patent protections extending into the mid-2030s, generics are unlikely in the near term. Patent expiry or challenges could eventually introduce lower-cost versions, affecting revenue.

5. What future indications could expand the use of Letermovir?
Possible expansion includes prophylaxis in solid organ transplant recipients, treatment of active CMV infections, or use in other immunocompromised populations. Such moves depend on supportive clinical trial data and regulatory approvals.

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References

[1] Tomblyn, M., et al. (2010). "Guidelines for preventing infectious complications among hematopoietic cell transplant recipients." Biology of Blood and Marrow Transplantation, 16(10), 1389-1424.

[2] European Medicines Agency. (2018). "Prevymis (Letermovir): Summary of Product Characteristics."

[3] Smith, C., et al. (2022). "Emerging CMV Therapeutics and Their Market Outlook." Transplant Infectious Disease, 24(4), e13740.

[4] Merck & Co. Annual Report. (2022).

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Note: All financial projections are estimates subject to market and regulatory variances and should be interpreted as forward-looking assessments.