The Discovery of Lovastatin for Lowering Cholesterol
A 1979 patent by Merck describing the isolation of a fermentation product from Aspergillus fungi that effectively lowers cholesterol levels in the blood.
Original patent title: “Hypocholesteremic fermentation products and process of preparation”
A 1979 patent by Merck describing the isolation of a fermentation product from Aspergillus fungi that effectively lowers cholesterol levels in the blood. Granted to Merck and Co Inc in 1980 with 2 claims and 490 forward citations, and it is now in the public domain.
Key facts
Coverage
What does this patent actually cover?
The patent details the isolation of a specific compound, initially designated MSD803, produced by fermenting the fungus Aspergillus. This compound, later known as lovastatin, functions as a potent inhibitor of cholesterol synthesis in the human body. The claimsclaimsThe numbered statements at the end of a patent that legally define what the inventor owns.Read more → specifically protect the chemical structure of this lactone compound and its corresponding hydroxy acid form, which are used to treat high cholesterol and lipid levels.
The gap
What does this patent NOT cover?
- Does not cover synthetic statins developed later that share different chemical backbones.
- Does not cover the general process of fermentation for non-cholesterol-lowering compounds.
- Does not cover the use of the compound for treating conditions unrelated to cholesterol or lipid metabolism.
These exclusions are unique to PatentBrief — derived from the actual claim language, not patent-office boilerplate.
What made this novel
The innovation was identifying that a natural byproduct of a common fungus could act as a precise 'off switch' for the enzyme HMG-CoA reductase, which is the rate-limiting step in human cholesterol production.
The Patent Drawing
Schematic visualization of the patent's claim structure. Hand-drawn diagrams in progress for each landmark patent.
Where you've seen this
Real-world examples
Mevacor
Generic lovastatin medications
Why it matters
The bigger picture
This patent marks the birth of the statin class of drugs, which became one of the most commercially successful and medically significant pharmaceutical categories in history. It provided a biological solution to heart disease by targeting the body's natural cholesterol production mechanism, fundamentally changing how doctors manage cardiovascular health.
Filed
June 15, 1979
Granted
November 4, 1980
Market context
Who's building on this
Companies in this space
Merck & Co. pioneered this space, but the success of this patent led to a massive wave of research by companies like Pfizer, AstraZeneca, and Bristol-Myers Squibb, who developed subsequent generations of statins like atorvastatin and rosuvastatin.
Market impact
This patent triggered a paradigm shift in cardiovascular medicine, moving the industry toward preventative pharmacological treatment of cholesterol. It created a multi-billion dollar market for statins and remains a cornerstone of modern preventative cardiology.
Claim 1 — Plain English
What this patent covers
The patent details the isolation of a specific compound, initially designated MSD803, produced by fermenting the fungus Aspergillus. This compound, later known as lovastatin, functions as a potent inhibitor of cholesterol synthesis in the human body. The claims specifically protect the chemical structure of this lactone compound and its corresponding hydroxy acid form, which are used to treat high cholesterol and lipid levels.
The clever bit
The innovation was identifying that a natural byproduct of a common fungus could act as a precise 'off switch' for the enzyme HMG-CoA reductase, which is the rate-limiting step in human cholesterol production.
What it does not cover
- Does not cover synthetic statins developed later that share different chemical backbones.
- Does not cover the general process of fermentation for non-cholesterol-lowering compounds.
- Does not cover the use of the compound for treating conditions unrelated to cholesterol or lipid metabolism.
Patent Journey
From filing to expiry
PatentBrief Score
Impact Score
Moderate
Citation count
40/40
Highly cited
Claim breadth
1/20
Narrow claimsclaimsThe numbered statements at the end of a patent that legally define what the inventor owns.Read more →
Recency
0/20
Older than 20 years
Assignee scale
0/20
Independent or smaller assigneeassigneeThe entity that owns the patent — usually the inventor's employer or a company.Read more →
PatentBrief Impact Score — based on citation count, claim breadth, recency, and assignee scale. Not a legal assessment.
Heuristic Value Estimate
What this patent might be worth
$90K – $288K
Midpoint $180K · expired or expiring · industry ×3.0
Heuristic only — blends forward/backward citation counts, claim scope, time remaining, litigation history, and CPC-derived industry baseline. Real valuations need a professional appraisal.
The original legal language
Original claims
2 claims as filed with the patent office.
Concepts involved
Citations
Patent lineage
Cite this patent
Monaghan, R. L., Alberts, A. W., Hoffman, C. H., & Albers-Schonberg, G. (1980). The Discovery of Lovastatin for Lowering Cholesterol (U.S. Patent No. 4,231,938). U.S. Patent and Trademark Office. https://patentbrief.org/patent/us/4231938/statin-cholesterol-lovastatin
Auto-generated from the patent record. Double-check author order and the issue date against the official USPTO document before submitting.
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Common Questions
Frequently Asked Questions
What does The Discovery of Lovastatin for Lowering Cholesterol cover?
A 1979 patent by Merck describing the isolation of a fermentation product from Aspergillus fungi that effectively lowers cholesterol levels in the blood.
Who owns patent US 4231938?
Merck and Co Inc owns this patent, granted in 1980.
When does this patent expire?
This patent has expired and is now in the public domain — anyone can use the invention freely.
What is patent US 4231938 cited by?
This patent has been cited by 490 later patents that build on its ideas.
What problem does this patent solve?
This patent marks the birth of the statin class of drugs, which became one of the most commercially successful and medically significant pharmaceutical categories in history. It provided a biological solution to heart disease by targeting the body's natural cholesterol production mechanism, fundamentally changing how doctors manage cardiovascular health.
What does this patent NOT cover?
Does not cover synthetic statins developed later that share different chemical backbones.
Patent monitoring