Last updated: October 29, 2026
VAQTA is Merck & Co.'s inactivated hepatitis A vaccine for adults and children. Its commercial profile is that of a mature, recurring vaccine franchise rather than a high-growth biologic. Demand is supported by routine pediatric immunization, international travel, outbreak response, occupational exposure, and vaccination of people with chronic liver disease or other risk factors. Merck does not separately disclose VAQTA revenue, unit volume, gross margin, or regional profitability. The product is reported within broader vaccine and pharmaceutical segment totals, which limits precise valuation.
What is VAQTA and how is it used?
VAQTA contains inactivated hepatitis A virus antigen and is administered by intramuscular injection. The U.S. label covers pediatric patients from 12 months through 18 years and adults 19 years and older. The standard primary series requires two doses, with the second dose administered at least six months after the first. The product is supplied in pediatric and adult presentations, including prefilled syringe and vial formats depending on market and product configuration. [1]
| Attribute |
VAQTA |
| Active product |
Inactivated hepatitis A vaccine |
| U.S. sponsor |
Merck Sharp & Dohme LLC |
| FDA approval type |
Biologics license application |
| U.S. BLA |
103606 |
| Pediatric use |
12 months through 18 years |
| Adult use |
19 years and older |
| Standard schedule |
Two doses, at least six months apart |
| Primary markets |
United States and international markets |
| Therapeutic category |
Preventive vaccine |
| Biosimilar exposure |
None in the conventional biosimilar sense |
VAQTA does not treat an existing hepatitis A infection. Its commercial demand depends on prevention policies, public-health recommendations, travel activity, and procurement contracts.
How large is the hepatitis A vaccine market?
The hepatitis A vaccine market is smaller than the markets for influenza, pneumococcal, human papillomavirus, or COVID-19 vaccines. It is also more fragmented by geography and use case.
U.S. demand is divided among:
- Routine childhood vaccination.
- Adult travel vaccination.
- Vaccination after exposure to hepatitis A.
- Vaccination for people experiencing homelessness.
- Vaccination for people who use drugs.
- Vaccination for men who have sex with men.
- Vaccination for people with chronic liver disease.
- State and local outbreak-control programs.
- Occupational and institutional vaccination.
The U.S. Centers for Disease Control and Prevention recommends routine hepatitis A vaccination for children beginning at age 1 and recommends vaccination for specified adult risk groups. This creates a baseline pediatric market, while adult demand remains more dependent on travel, public-health campaigns, and risk-based uptake. [2]
Hepatitis A vaccination also has a substantial international component. Countries differ in whether they use universal childhood vaccination, risk-based vaccination, or travel-focused vaccination. That variation limits the ability of a manufacturer to apply one global pricing or reimbursement model.
What are VAQTA's main competitors?
The principal U.S. single-antigen competitor is Havrix, marketed by GSK. Combination hepatitis A and hepatitis B products such as Twinrix compete for adult travel and risk-based vaccination demand. International markets also include additional products, including locally approved hepatitis A vaccines and combination formulations.
| Product |
Company |
Product type |
Main competitive position |
| VAQTA |
Merck |
Hepatitis A vaccine |
Established U.S. and international product |
| Havrix |
GSK |
Hepatitis A vaccine |
Direct single-antigen competitor |
| Twinrix |
GSK |
Hepatitis A and B combination vaccine |
Competes in adult and travel vaccination |
| Pediatric combination products |
Multiple manufacturers |
Combination childhood vaccines |
Can reduce demand for separate injections in some markets |
| Local-market hepatitis A vaccines |
Regional manufacturers |
Hepatitis A vaccine |
Relevant in international tenders and public programs |
VAQTA competes primarily on supply reliability, regulatory approvals, procurement access, physician familiarity, contract pricing, and availability in the required presentation. Clinical differentiation is limited because all major products aim to induce protective immunity against hepatitis A.
What is VAQTA's financial trajectory?
VAQTA revenue is not separately reported by Merck. Merck's public financial statements aggregate products into broader categories, including vaccines and pharmaceutical franchises. Gardasil/Gardasil 9 is the dominant disclosed growth driver in Merck's vaccine portfolio, while mature products such as VAQTA contribute to the portfolio's recurring base but cannot be isolated in reported revenue. [3]
This produces three financial conclusions:
- VAQTA is commercially meaningful as part of Merck's vaccine infrastructure, but its standalone revenue is not publicly measurable from SEC filings.
- VAQTA is unlikely to be a major contributor to Merck's consolidated growth because its market is mature and its product category is substantially smaller than Gardasil.
- Revenue is more likely to track vaccination volumes, tenders, travel activity, and supply availability than major price increases.
Financial drivers
The most important drivers are:
- Pediatric immunization coverage.
- Travel-related vaccination demand.
- Hepatitis A outbreaks in the United States.
- Government and institutional procurement.
- Product availability and manufacturing capacity.
- Reimbursement for adult vaccination.
- Competition from Havrix and combination hepatitis A/hepatitis B vaccines.
- Changes in national immunization schedules.
- International tender awards and currency movements.
Outbreaks can create temporary demand increases, particularly when public-health agencies purchase vaccine for targeted populations. These events may lift units without producing a durable change in annual demand. Pediatric vaccination provides greater stability but is exposed to missed appointments, public-health disruption, and changes in vaccine administration practices.
When does VAQTA lose exclusivity?
VAQTA does not have a single publicly established small-molecule patent expiry date. It is a vaccine biologic licensed under a BLA, not a conventional small-molecule drug approved through an NDA.
The FDA Orange Book primarily records approved drug products and associated patent and exclusivity information for NDA products. Biologics licensed under the Public Health Service Act are generally evaluated through the Purple Book framework rather than through standard Orange Book listing practices. [4,5]
VAQTA's effective exclusivity therefore depends on several factors:
| Exclusivity factor |
VAQTA relevance |
| Patent term |
Potentially relevant, but no complete VAQTA-specific patent term is identified in the FDA label |
| Regulatory exclusivity |
Biologic regulatory protections may apply depending on the product's statutory pathway and reference-product status |
| Manufacturing know-how |
Important for antigen production, purification, inactivation, potency, sterility, and release testing |
| Trade secrets |
Potentially material even when patents expire |
| Market access |
Contracts, physician familiarity, and distribution relationships |
| Substitutability |
Limited compared with conventional generic drugs |
A competitor cannot generally launch a conventional "generic VAQTA" through an automatic-substitution pathway. A competing hepatitis A vaccine would need its own regulatory approval and manufacturing package. A biosimilar pathway is conceptually available for certain biological products, but vaccines have product-specific analytical, clinical, manufacturing, and regulatory requirements that make substitution less straightforward.
Are there Paragraph IV challenges to VAQTA?
Paragraph IV litigation is not the normal challenge mechanism for VAQTA because Paragraph IV certifications apply to patents listed in the Orange Book for approved drug products. A competing vaccine sponsor would more likely pursue its own biologics license, rely on independent manufacturing data, or challenge relevant patent rights through separate patent litigation.
No major publicly disclosed Paragraph IV campaign is associated with VAQTA in the standard generic-drug sense. The absence of Paragraph IV activity does not mean VAQTA has no patent or exclusivity exposure. It means the conventional ANDA challenge model is not the principal route to competition.
What patent and manufacturing rights protect VAQTA?
The strongest practical barriers for an established vaccine such as VAQTA are likely to be manufacturing and regulatory capabilities rather than one identifiable composition-of-matter patent.
Potentially relevant protection areas include:
- Viral seed and cell-substrate control.
- Antigen production and purification.
- Chemical inactivation conditions.
- Adjuvant and formulation parameters.
- Sterility and potency testing.
- Stability and shelf-life controls.
- Container-closure systems.
- Scale-up and batch consistency.
- Regulatory data and process validation.
- Supplier qualification for specialized inputs.
The FDA prescribing information does not provide a complete patent schedule. Merck's annual reports do not identify a standalone VAQTA patent family with a specific terminal expiration date. Patent rights could exist at the process, formulation, packaging, or manufacturing level, but the commercial barrier can remain significant after patent expiry because vaccine production requires validated facilities and consistent regulatory performance.
What is the FDA and Orange Book status of VAQTA?
VAQTA is FDA-approved as a hepatitis A vaccine under BLA 103606. Its regulatory status is that of a licensed biologic, not an NDA-approved small-molecule product. It is therefore not evaluated as a conventional Orange Book generic-substitution product.
The main regulatory implications are:
- A competitor cannot normally use an ANDA to create an automatically substitutable generic version.
- A competing manufacturer must establish product quality, safety, potency, and manufacturing controls through an appropriate biologics pathway.
- Vaccine lot release, inspection, and postmarketing surveillance remain material commercial obligations.
- Changes in manufacturing or formulation can require regulatory review and supplemental approval.
What litigation and settlement activity affects VAQTA?
No major publicly reported patent settlement or generic-entry settlement is a defining feature of VAQTA's current commercial profile. The product's competition is primarily commercial and regulatory rather than driven by a high-profile patent dispute.
Relevant legal risks would include:
- Patent disputes over vaccine manufacturing or formulation.
- Contract disputes involving government procurement.
- Product-liability claims.
- Manufacturing deviations or recalls.
- Regulatory enforcement involving quality systems.
- Competition for public-sector tenders.
These risks can affect supply and reputation even when they do not produce a formal loss-of-exclusivity event.
What generic or follow-on launch risks exist?
The principal launch risk is follow-on vaccine competition rather than a conventional generic launch. A competitor could enter through:
- A separately developed hepatitis A vaccine.
- A combination hepatitis A/hepatitis B product.
- A pediatric combination product that reduces separate-dose demand.
- A regionally approved vaccine sold through tenders.
- A biologic product with sufficient analytical and clinical support for the applicable regulatory pathway.
The near-term threat is moderated by manufacturing complexity, validation costs, cold-chain requirements, and the need to win procurement contracts. The threat increases in markets where hepatitis A vaccination is treated as a commodity product and where tenders emphasize price.
How does VAQTA compare with other Merck vaccine franchises?
VAQTA has a different financial profile from Gardasil/Gardasil 9.
| Factor |
VAQTA |
Gardasil/Gardasil 9 |
| Disease area |
Hepatitis A |
HPV-related disease |
| Demand base |
Pediatric, travel, risk-based, outbreak |
Broad adolescent and adult prevention |
| Growth profile |
Mature and relatively stable |
Historically larger growth and revenue contribution |
| Pricing power |
Constrained by tenders and competition |
Stronger in many private and public channels |
| Competitive intensity |
Havrix and combination products |
Multiple global and regional competitive pressures |
| Revenue disclosure |
Not separately disclosed |
Separately disclosed by Merck |
| Strategic role |
Portfolio stability and vaccine breadth |
Major growth franchise |
VAQTA is better viewed as a durable portfolio product than as a primary growth asset.
What is the outlook for VAQTA revenue?
The base-case outlook is stable to modestly declining nominal revenue, with periodic volume spikes. Upside could come from stronger travel activity, hepatitis A outbreaks, expanded adult vaccination, or increased public-health purchasing. Downside could come from reduced travel, lower routine immunization rates, tender price pressure, supply interruptions, or substitution by combination vaccines.
Because Merck does not disclose VAQTA sales, an external analyst should avoid assigning a precise revenue forecast from company-level vaccine data. Merck's aggregate vaccine performance cannot be used as a direct proxy for VAQTA because Gardasil dominates the segment's reported economics.
What is the geographic coverage of VAQTA?
VAQTA has a broad international commercial footprint, but approval, product presentation, dosing rules, and reimbursement vary by country. The most attractive markets generally have:
- National or regional hepatitis A vaccination programs.
- High outbound travel volumes.
- Strong private vaccination channels.
- Government-funded outbreak response.
- Established cold-chain infrastructure.
- Stable procurement budgets.
International revenue is exposed to foreign exchange, tender timing, local pricing controls, and country-specific supply requirements.
Key Takeaways
- VAQTA is Merck's established inactivated hepatitis A vaccine for pediatric and adult use.
- Its demand is supported by routine childhood vaccination, travel, outbreak response, and risk-based adult immunization.
- Merck does not separately disclose VAQTA revenue, units, margins, or profitability.
- Gardasil is the principal growth driver in Merck's vaccine portfolio; VAQTA is a mature supporting asset.
- Havrix is the main direct U.S. competitor, while Twinrix and other combination products create additional substitution pressure.
- Paragraph IV litigation is not the standard competitive mechanism because VAQTA is a BLA-approved biologic rather than an Orange Book small-molecule product.
- The strongest barriers are validated manufacturing, regulatory compliance, supply reliability, and procurement access.
- The likely commercial trajectory is stable to modestly declining, interrupted by travel cycles, outbreaks, tenders, and public-health campaigns.
- No publicly disclosed VAQTA-specific patent expiry date provides a definitive generic-entry date.
FAQs
Is VAQTA still commercially available?
VAQTA remains an FDA-licensed hepatitis A vaccine product marketed by Merck, subject to market-specific availability and supply conditions.
Is VAQTA interchangeable with Havrix?
VAQTA and Havrix are competing hepatitis A vaccines, but interchangeability depends on the applicable public-health guidance, product labeling, jurisdiction, and vaccination circumstances.
Can a biosimilar replace VAQTA automatically?
No. VAQTA is not subject to conventional automatic generic substitution. A competing biologic vaccine would require its own regulatory authorization and would not automatically substitute for VAQTA in the same way as an FDA-rated generic drug.
Does VAQTA have a known patent expiration date?
No single definitive VAQTA patent expiration date is identified in the FDA prescribing information or Merck's public financial disclosures. Manufacturing and regulatory protections may remain relevant after individual patent terms expire.
What is the biggest commercial risk to VAQTA?
The largest risks are mature-market demand, price competition in tenders, combination-vaccine substitution, manufacturing interruptions, and limited growth in adult hepatitis A vaccination outside travel and outbreak settings.
References
-
U.S. Food and Drug Administration. (2023). VAQTA [prescribing information]. Merck Sharp & Dohme LLC.
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Centers for Disease Control and Prevention. (2024). Hepatitis A vaccination: Information for health care providers. U.S. Department of Health and Human Services.
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Merck & Co., Inc. (2024). 2023 annual report. Rahway, NJ: Merck & Co., Inc.
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U.S. Food and Drug Administration. (2024). Orange Book: Approved drug products with therapeutic equivalence evaluations. U.S. Department of Health and Human Services.
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U.S. Food and Drug Administration. (2024). Purple Book: Database of licensed biological products. U.S. Department of Health and Human Services.
