CAMZYOS Drug Patent Profile

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

Camzyos is a drug marketed by Bristol and is included in one NDA. There are two patents protecting this drug and one Paragraph IV challenge.

The generic ingredient in CAMZYOS is mavacamten. There is one drug master file entry for this compound. One supplier is listed for this compound. Additional details are available on the mavacamten profile page.

DrugPatentWatch^® Generic Entry Outlook for Camzyos

Camzyos was eligible for patent challenges on April 28, 2026.

By analyzing the patents and regulatory protections it appears that the earliest date for generic entry will be April 28, 2036. This may change due to patent challenges or generic licensing.

There have been seven patent litigation cases involving the patents protecting this drug, indicating strong interest in generic launch. Recent data indicate that 63% of patent challenges are decided in favor of the generic patent challenger and that 54% of successful patent challengers promptly launch generic drugs.

Indicators of Generic Entry

Summary for CAMZYOS

US Patents:	2
Applicants:	1
NDAs:	1
Finished Product Suppliers / Packagers:	1
Raw Ingredient (Bulk) Api Vendors:	22
Clinical Trials:	1
Patent Applications:	85
Drug Prices:	Drug price information for CAMZYOS
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for CAMZYOS
What excipients (inactive ingredients) are in CAMZYOS?	CAMZYOS excipients list
DailyMed Link:	CAMZYOS at DailyMed

See drug prices for CAMZYOS

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

Constraining patent/regulatory exclusivity:

RE50050

NDA:

214998

Dosage:

CAPSULE;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 CAMZYOS

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

Sponsor	Phase
University of Manchester	NA

See all CAMZYOS clinical trials

Pharmacology for CAMZYOS

Drug Class	Cardiac Myosin Inhibitor
Mechanism of Action	Cardiac Myosin Inhibitors

Paragraph IV (Patent) Challenges for CAMZYOS

Tradename	Dosage	Ingredient	Strength	NDA	ANDAs Submitted	Submissiondate
CAMZYOS	Capsules	mavacamten	2.5 mg, 5 mg, 10 mg and 15 mg	214998	7	2026-04-28

US Patents and Regulatory Information for CAMZYOS

CAMZYOS is protected by two US patents and three FDA Regulatory Exclusivities.

This potential generic entry date is based on patent RE50050.

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
Bristol	CAMZYOS	mavacamten	CAPSULE;ORAL	214998-001	Apr 28, 2022		RX	Yes	No	9,585,883
Bristol	CAMZYOS	mavacamten	CAPSULE;ORAL	214998-004	Apr 28, 2022		RX	Yes	No
Bristol	CAMZYOS	mavacamten	CAPSULE;ORAL	214998-002	Apr 28, 2022		RX	Yes	Yes	RE50050		Y	Y
Bristol	CAMZYOS	mavacamten	CAPSULE;ORAL	214998-001	Apr 28, 2022		RX	Yes	No
Bristol	CAMZYOS	mavacamten	CAPSULE;ORAL	214998-003	Apr 28, 2022		RX	Yes	No	RE50050		Y	Y
Bristol	CAMZYOS	mavacamten	CAPSULE;ORAL	214998-004	Apr 28, 2022		RX	Yes	No

EU/EMA Drug Approvals for CAMZYOS

Company	Drugname	Inn	Product Number / Indication	Status	Generic	Biosimilar	Orphan	Marketing Authorisation	Marketing Refusal
Bristol-Myers Squibb Pharma EEIG	Camzyos	mavacamten	EMEA/H/C/005457Treatment of symptomatic obstructive hypertrophic cardiomyopathy.	Authorised	no	no	no	2023-06-26

International Patents for CAMZYOS

When does loss-of-exclusivity occur for CAMZYOS?

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

Australia

Brazil

Canada

Chile

China

Costa Rica

Croatia

Cyprus

Denmark

Dominican Republic

Eurasian Patent Organization

European Patent Office

Finland

France

Guatemala

Hong Kong

Hungary

Israel

Japan

Lithuania

Malaysia

Mexico

Morocco

Netherlands

New Zealand

Norway

Peru

Philippines

Poland

Portugal

Serbia

Singapore

Slovenia

South Africa

South Korea

Spain

Tunisia

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 CAMZYOS around the world.

Country	Patent Number	Title	Estimated Expiration
Australia	2014281408
Australia	2018264088
Australia	2020204271
Australia	2022202298
Australia	2024202464
Australia	2026204344

Supplementary Protection Certificates for CAMZYOS

Patent Number	Supplementary Protection Certificate	SPC Country	SPC Expiration	SPC Description
3010910	CR 2023 00034	Denmark		PRODUCT NAME: MAVACAMTEN ELLER ET FARMACEUTISK ACCEPTABELT SALT DERAF; REG. NO/DATE: EU/1/23/1716 20230627
3010910	301253	Netherlands		PRODUCT NAME: MAVACAMTEN OF EEN FARMACEUTISCH AANVAARDBAAR ZOUT DAARVAN; REGISTRATION NO/DATE: EU/1/23/1716 20230627
3010910	PA2023535	Lithuania		PRODUCT NAME: MAVAKAMTENAS ARBA FARMACINIU POZIURIU PRIIMTINA JO DRUSKA; REGISTRATION NO/DATE: EU/1/23/1716 20230626
3010910	2023C/546	Belgium		PRODUCT NAME: MAVACAMTEN OU UN SEL PHARMACEUTIQUEMENT ACCEPTABLE DE CELUI-CI; AUTHORISATION NUMBER AND DATE: EU/1/23/1716 20230627
3010910	LUC00324	Luxembourg		PRODUCT NAME: MAVACAMTEN OR A PHARMACEUTICALLY ACCEPTABLE SALT THEREOF; AUTHORISATION NUMBER AND DATE: EU/1/23/1716 20230627
3010910	122023000063	Germany		FORMER OWNER: MYOKARDIA, INC., 94080 SOUTH SAN FRANCISCO, CA, US

Camzyos Market Dynamics and Financial Trajectory: Mavacamten Sales, Competition, Patent Risk and Growth Outlook

Last updated: August 15, 2026

Camzyos, Bristol Myers Squibb’s mavacamten, is the first approved cardiac myosin inhibitor and the leading pharmaceutical treatment specifically targeting the underlying hypercontractility of obstructive hypertrophic cardiomyopathy. Its commercial trajectory is driven by a large underdiagnosed patient population, high annual pricing, and expansion of specialist prescribing. Growth is constrained by the FDA-mandated Risk Evaluation and Mitigation Strategy, drug-interaction restrictions, pregnancy-related controls, and the expected entry of competing cardiac myosin inhibitors.

Bristol Myers Squibb acquired Camzyos through its $13.1 billion acquisition of MyoKardia in 2020. The drug received FDA approval in April 2022 for adults with symptomatic New York Heart Association class II-III obstructive hypertrophic cardiomyopathy to improve functional capacity and symptoms.[1][2]

How large is the Camzyos market?

The addressable market is substantial but narrower than the total hypertrophic cardiomyopathy population.

Hypertrophic cardiomyopathy affects approximately one in 500 people. Roughly two-thirds of patients have left ventricular outflow tract obstruction, although only a portion are diagnosed, symptomatic, medically appropriate, and reachable through specialist channels.[3] The practical commercial market consists of patients with symptomatic obstructive disease who remain inadequately controlled on beta blockers, calcium-channel blockers, or disopyramide, as well as newly diagnosed patients entering treatment.

Market component	Commercial relevance
Estimated HCM prevalence	Approximately 1 in 500 people
Obstructive HCM share	Approximately two-thirds of HCM cases
Initial FDA indication	Symptomatic NYHA class II-III obstructive HCM
Primary prescribers	Cardiologists, HCM centers, advanced heart-failure specialists
Administration	Oral, once daily
U.S. annual list price	Approximately $89,000, subject to payer discounts and rebates
Distribution model	Restricted specialty distribution and monitoring through the CAMZYOS REMS

Camzyos does not compete only with other branded drugs. Its main commercial alternatives are inexpensive generic medicines, including metoprolol, propranolol, verapamil, diltiazem, and disopyramide. That makes Camzyos a high-value, high-price intervention that must demonstrate superior symptom control, functional benefit, or avoidance of septal reduction procedures.

What are Camzyos sales and revenue trends?

Camzyos sales have followed a rapid launch curve, although the product remains a small contributor to Bristol Myers Squibb’s total revenue.

Fiscal year	Approximate Camzyos revenue	Commercial development
2022	Approximately $12 million	Partial-year U.S. launch
2023	Approximately $171 million	Broader specialist adoption and REMS infrastructure
2024	Approximately $350 million-$360 million	Continued prescription growth and international expansion

Bristol Myers Squibb reported that Camzyos revenue increased sharply from 2022 to 2023 and continued to expand in 2024.[4] The product’s percentage growth is high because it started from a small base. Its absolute contribution remains modest against Bristol Myers Squibb’s annual revenue of more than $45 billion.

What is driving Camzyos revenue growth?

The key growth factors are:

1. Increased diagnosis of obstructive HCM through echocardiography, cardiac MRI, genetic evaluation, and referral to specialty centers.
2. Greater physician familiarity with cardiac myosin inhibition.
3. Use in patients who remain symptomatic despite conventional negative inotropic therapy.
4. Reimbursement development and increased payer coverage.
5. International launches, particularly in markets with established HCM specialty care.
6. Potential use earlier in the treatment sequence, subject to clinical evidence and labeling.

Camzyos has a premium price relative to conventional HCM therapy, but it can be economically relevant if it reduces hospitalizations, improves exercise capacity, delays septal reduction therapy, or reduces the need for invasive procedures. Long-term claims data will influence payer willingness to maintain broad coverage.

What is the FDA status of Camzyos?

Camzyos is FDA-approved for adults with symptomatic NYHA class II-III obstructive HCM. The FDA approval was based primarily on the EXPLORER-HCM trial, in which mavacamten improved a composite measure of exercise capacity and symptoms compared with placebo.[1][5]

The VALOR-HCM study provided additional evidence in patients who were eligible for septal reduction therapy. Mavacamten reduced the proportion of patients proceeding to surgery or alcohol septal ablation and improved clinical measures relative to placebo.[6]

The major regulatory limitation is the risk of left ventricular systolic dysfunction and heart failure. The FDA therefore requires:

• Baseline and periodic echocardiograms.
• Enrollment in the CAMZYOS REMS.
• Restricted dispensing through certified pharmacies.
• Prescriber and pharmacy certification.
• Pregnancy testing and contraception requirements for patients who can become pregnant.
• Review of drug interactions involving CYP2C19 and CYP3A4.
• Dose interruption or adjustment when ventricular function declines or interacting medicines are introduced.

These controls protect patients but increase friction in prescribing, dispensing, refill continuity, and expansion into lower-resource cardiology practices.

When does Camzyos lose exclusivity?

Camzyos is protected by a combination of composition-of-matter, formulation, manufacturing, and method-of-use rights. Bristol Myers Squibb’s regulatory and patent disclosures indicate protection extending into the early 2030s for important U.S. rights, although individual Orange Book patent dates differ by patent and claim scope.[4][7]

The practical exclusivity timeline is:

Period	Expected commercial position
2022-2024	U.S. launch and market establishment
2025-2028	Main growth period; limited direct cardiac myosin competition
2029-2031	Increasing litigation, patent-certification, and label-scrubbing risk
Early 2030s	Potential U.S. generic entry depending on patent validity, settlements, pediatric extensions, and regulatory exclusivity

The primary risk is not a single expiration date. It is the interaction between Orange Book-listed patents, non-listed patent rights, patent-term adjustments, pediatric exclusivity, Paragraph IV litigation, and potential settlements.

What patents protect Camzyos?

Camzyos protection is expected to cover several layers:

• Mavacamten chemical composition.
• Specific crystalline or polymorphic forms.
• Pharmaceutical compositions.
• Dosing regimens.
• Treatment of obstructive HCM.
• Reduction of left ventricular outflow tract obstruction.
• Manufacturing and purification processes.

The strongest protection normally comes from composition claims if they remain valid. Formulation and method-of-use patents can delay or narrow generic competition, but they are more vulnerable to non-infringement arguments, obviousness challenges, and label-scrubbing strategies.

The FDA Orange Book is the controlling source for listed patents and regulatory exclusivity. Bristol Myers Squibb’s annual reports and SEC filings should be read with the Orange Book because corporate disclosures describe broader patent portfolios than the patents directly tied to an approved product.[4][7]

Are generic companies challenging Camzyos patents?

A generic challenge would most likely take the form of an Abbreviated New Drug Application with Paragraph IV certifications against one or more listed patents. A Paragraph IV certification alleges that a patent is invalid, unenforceable, or not infringed. If BMS files suit within the statutory period, FDA approval of the ANDA is generally subject to a 30-month stay, subject to litigation outcomes and court rulings.[8]

Potential generic strategies include:

• Challenging the chemical composition patent.
• Arguing that a later patent claims an obvious formulation or dosing regimen.
• Designing around crystalline-form claims.
• Omitting patented HCM indications from the generic label.
• Contesting the scope of REMS-related or monitoring claims.
• Seeking approval after the earliest unexpired patent while continuing litigation over later patents.

As of the latest public regulatory information available for the product’s early commercial period, Camzyos had no approved U.S. generic equivalent. The probability of early generic entry depends on the strength of the core composition claims and whether BMS resolves future litigation through a settlement.

What patent litigation and settlement risks affect Camzyos?

Bristol Myers Squibb’s litigation exposure is likely to increase as the product approaches its first major generic challenge window. The most important legal questions will be:

1. Whether core mavacamten composition claims remain enforceable.
2. Whether polymorph and formulation claims survive obviousness challenges.
3. Whether generic applicants can obtain approval with an indication carve-out.
4. Whether BMS can prove infringement of dosing or method-of-use claims.
5. Whether a settlement allows a generic launch before the last listed patent expires.

A settlement could protect revenue by delaying entry, but it would also establish a fixed erosion date. The commercial value of a settlement would depend on the remaining patent term, the number of challengers, and whether multiple generic companies receive coordinated or staggered launch rights.

Which companies are challenging Camzyos commercially?

The most important future competitor is aficamten, Cytokinetics’ next-generation cardiac myosin inhibitor. Aficamten produced positive results in the SEQUOIA-HCM phase 3 study in symptomatic obstructive HCM.[9] It is designed to offer a shorter half-life and potentially more predictable dose management than mavacamten.

Product	Company	Mechanism	Market status	Competitive issue
Camzyos, mavacamten	Bristol Myers Squibb	Cardiac myosin inhibitor	FDA-approved	First-mover position, established efficacy, REMS burden
Aficamten	Cytokinetics	Cardiac myosin inhibitor	Clinical-stage through the reported period	Potentially simpler titration and monitoring profile
Beta blockers	Generic manufacturers	Reduce heart rate and contractility	Standard of care	Low cost and broad familiarity
Verapamil/diltiazem	Generic manufacturers	Calcium-channel blockade	Standard of care	Lower price but variable efficacy
Disopyramide	Multiple manufacturers	Negative inotropy	Niche use	Anticholinergic and tolerability limitations
Septal reduction therapy	Hospitals and surgical centers	Procedural reduction of obstruction	Established intervention	Invasive but durable for selected patients

Aficamten could pressure Camzyos through physician switching, formulary competition, and price negotiations. Its commercial profile will depend on whether regulators and physicians view its monitoring requirements as materially easier and whether it demonstrates comparable outcomes in nonobstructive HCM.

Can Camzyos expand into nonobstructive hypertrophic cardiomyopathy?

Nonobstructive HCM is the most important clinical expansion opportunity, but it is also a major development risk.

Bristol Myers Squibb’s ODYSSEY-HCM phase 3 study did not meet its primary endpoints in patients with symptomatic nonobstructive HCM.[10] The result weakened the near-term case for a broad label expansion and reduced the probability that Camzyos would address the full HCM population through the same development program.

The failed expansion has several financial consequences:

• The revenue opportunity is concentrated in obstructive HCM.
• BMS must rely more heavily on market penetration within the existing indication.
• Aficamten may gain a development advantage if it produces stronger nonobstructive-HCM data.
• Long-term revenue estimates should not assume approval across all HCM phenotypes.
• Payer negotiations may focus more heavily on measurable reductions in procedures and hospital events.

What manufacturing and intellectual-property barriers protect Camzyos?

Mavacamten is a small molecule, so it does not have the manufacturing complexity associated with biologics. Generic manufacturers can generally reproduce small-molecule active ingredients more readily than monoclonal antibodies. The main barriers are regulatory and IP-related rather than biological manufacturing barriers.

Relevant barriers include:

• Demonstrating pharmaceutical equivalence and bioequivalence.
• Reproducing the approved dosage forms and specifications.
• Addressing polymorph or solid-state claims.
• Establishing a safe dispensing and monitoring process.
• Managing CYP-mediated interaction risks.
• Supporting a generic label that does not infringe method-of-use claims.
• Meeting the commercial requirements of a restricted-distribution program.

Camzyos’s REMS may make generic commercialization more operationally complex, but it is unlikely by itself to create durable exclusivity if a generic company can satisfy FDA requirements.

How does Camzyos compare with standard HCM treatments?

Camzyos is differentiated by disease-modifying hemodynamic activity rather than by symptomatic rate control alone. In clinical trials, it reduced left ventricular outflow tract obstruction and improved composite measures involving exercise capacity and symptoms.[5]

Its disadvantages are operational:

• It requires serial echocardiographic monitoring.
• It has clinically significant drug interactions.
• It is contraindicated in pregnancy.
• It has a high annual list price.
• It requires enrollment in the REMS program.
• Long-term real-world safety data are less mature than for generic beta blockers.

The commercial opportunity is strongest in patients with persistent symptoms, marked obstruction, or a desire to avoid or delay invasive septal reduction therapy. The opportunity is weaker in mildly symptomatic patients who are well controlled on low-cost generics.

What generic entry scenarios exist for Camzyos?

Three scenarios define the principal U.S. erosion risk.

Early entry after patent invalidation

A successful Paragraph IV challenge could produce entry before the early 2030s. This would materially reduce revenue through price erosion and rapid formulary substitution, particularly if multiple generic manufacturers launch simultaneously.

Negotiated entry

BMS could settle with one or more generic applicants and permit entry on an agreed date. This would preserve revenue until the settlement date but create a defined erosion event.

Delayed entry after patent expiry

If composition and secondary patents withstand litigation, generic entry could be deferred until the early 2030s. Revenue would then depend on continued penetration, international sales, and any new indications.

Because Camzyos is a small-molecule product with a high list price, post-entry gross-to-net and price erosion could be substantial. The first generic launch could cause a sharp decline, followed by faster erosion as additional manufacturers enter.

What is the long-term financial outlook for Camzyos?

Camzyos has a credible path to becoming a multibillion-dollar product only if BMS achieves much higher penetration within obstructive HCM and maintains a strong position against aficamten. The product’s near-term growth rate can remain high because diagnosis and specialist adoption are still developing.

The most important financial variables are:

• Number of diagnosed obstructive HCM patients.
• Share treated with Camzyos rather than generic therapy.
• Reimbursement and prior-authorization requirements.
• Persistence and discontinuation rates.
• Average net price after rebates.
• International regulatory approvals and reimbursement.
• Uptake in patients eligible for septal reduction therapy.
• Competitive differentiation against aficamten.
• Timing of Paragraph IV litigation and generic entry.

The failed nonobstructive-HCM study limits upside. A reasonable commercial framework places Camzyos in a period of strong growth through the second half of the 2020s, followed by increasing competitive and patent pressure as the product approaches its primary U.S. loss-of-exclusivity window.

What is the international market position of Camzyos?

Bristol Myers Squibb has pursued approvals outside the United States, including European and other international markets. International revenue will be lower per patient because of government price controls, health technology assessment requirements, and restricted reimbursement. However, additional countries expand the diagnosed patient pool and reduce dependence on U.S. pricing.

Market access will depend on:

• Demonstrated reduction in symptoms and obstruction.
• Budget impact relative to generic therapy.
• Avoidance or delay of septal reduction procedures.
• Availability of specialist echocardiography.
• National requirements for prior authorization.
• Local treatment guidelines for HCM.

The United States should remain the economic center of the franchise because of higher pricing and faster specialist adoption.

Key Takeaways

• Camzyos is the first FDA-approved cardiac myosin inhibitor for symptomatic obstructive HCM.
• Bristol Myers Squibb revenue increased from approximately $12 million in 2022 to about $171 million in 2023 and roughly $350 million-$360 million in 2024.
• The commercial market is large, but the practical near-term opportunity is concentrated in diagnosed symptomatic obstructive HCM.
• The CAMZYOS REMS supports safety but adds prescribing and dispensing friction.
• Nonobstructive-HCM expansion suffered a major setback after the negative ODYSSEY-HCM study.
• Aficamten is the most important potential branded competitor.
• Patent protection and litigation are likely to remain important through the late 2020s, with meaningful generic-entry risk in the early 2030s.
• Camzyos has strong near-term growth prospects but a narrower long-term opportunity than earlier broad-HCM forecasts implied.

FAQs

Is Camzyos expected to become a blockbuster drug?

Camzyos has blockbuster potential, but reaching annual sales above $1 billion requires substantial penetration among diagnosed obstructive HCM patients, continued reimbursement support, and successful defense against aficamten.

Why is Camzyos so expensive compared with beta blockers?

Camzyos is priced as a targeted therapy supported by clinical trial evidence showing reductions in obstruction and improvements in symptoms and exercise capacity. Beta blockers are generic medicines with much lower manufacturing and development costs.

Does Camzyos reduce the need for septal myectomy?

Camzyos can reduce the proportion of eligible patients proceeding to septal reduction therapy, as shown in VALOR-HCM. It does not eliminate the need for surgery or ablation in all patients.[6]

Could aficamten replace Camzyos?

Aficamten could take market share if it offers similar efficacy with simpler monitoring, fewer treatment interruptions, or better payer economics. Replacement risk will depend on its FDA label, safety profile, pricing, and real-world adoption.

What is the largest risk to Camzyos revenue?

The largest risks are narrower-than-expected patient penetration, the failure of nonobstructive-HCM expansion, competition from aficamten, and an earlier-than-expected generic launch following successful patent litigation.

References

1. U.S. Food and Drug Administration. (2022). CAMZYOS (mavacamten) prescribing information. https://www.accessdata.fda.gov
2. Bristol Myers Squibb. (2020). Bristol Myers Squibb completes acquisition of MyoKardia. https://news.bms.com
3. Ommen, S. R., Mital, S., Burke, M. A., et al. (2020). 2020 AHA/ACC guideline for the diagnosis and treatment of patients with hypertrophic cardiomyopathy. Circulation, 142(25), e558-e631.
4. Bristol Myers Squibb. (2024). Annual report and Form 10-K. https://www.bms.com/investors
5. Olivotto, I., Ore, A., Autore, C., et al. (2020). Mavacamten for treatment of symptomatic obstructive hypertrophic cardiomyopathy. The Lancet, 396(10253), 759-769.
6. Desai, M. Y., Owens, A., Wolski, K., et al. (2022). Mavacamten in patients with hypertrophic cardiomyopathy referred for septal reduction therapy. New England Journal of Medicine, 387, 1487-1499.
7. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations, Orange Book. https://www.fda.gov/drugs/drug-approvals-and-databases/orange-book
8. U.S. Food and Drug Administration. (2024). Hatch-Waxman amendments and abbreviated new drug applications. https://www.fda.gov
9. Cytokinetics, Inc. (2023). SEQUOIA-HCM topline results for aficamten. https://ir.cytokinetics.com
10. Bristol Myers Squibb. (2024). ODYSSEY-HCM topline results. https://news.bms.com

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