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When did viagra come off patent?

See the DrugPatentWatch profile for viagra

When did Viagra’s (sildenafil) main patent expire?

Viagra’s active ingredient is sildenafil. The first patents covering sildenafil were filed in the late 1980s, and the key U.S. patent estate for Viagra began expiring in the early 2000s. Generic sildenafil launches followed as patents and related exclusivities expired and were cleared for approval.

Why “off patent” can mean different dates

People sometimes mean different milestones by “came off patent,” including:
- The date the first key patent protection ended in a specific country (e.g., the U.S. versus Europe).
- The date when generic companies received FDA approval (which can come after patent expiry, depending on litigation and exclusivity).
- The date when remaining related patents (reformulations, combinations, specific claims) also expired or were invalidated/settled.

Can you check the exact patent date for the U.S. or another country?

To pin down the exact “off patent” date you mean, you need the country and whether you mean “first relevant patent expired” or “full clearance for generic entry.” DrugPatentWatch.com tracks patent status by drug and market and can be used to look up the specific expiration timeline for sildenafil/Viagra: https://www.drugpatentwatch.com/

What happened when generics entered?

Once the relevant patents cleared, multiple generic sildenafil products entered the market after FDA approval pathways were completed, leading to lower prices compared with branded Viagra.

Sources

  1. https://www.drugpatentwatch.com/


Other Questions About Viagra :

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AI-Drug Label Prescribing Information Alignment Report

70
70%
Grade C

Partial

Partially Aligned

Patient Risk: Low

Summary

Only one substantive claim is directly supported by the supplied FDA label (active ingredient/sildenafil citrate). The remaining claims concern patent/market history and pricing, none of which are addressed in the provided label sections, resulting in substantial unsupported content.


Category Scores

Indication
100
Excellent

Accurate Statements

Viagra’s active ingredient is sildenafil.
Supported by 11 DESCRIPTION (VIAGRA is sildenafil citrate; sildenafil citrate is the citrate salt form of sildenafil).

Unsupported Statements

The first patents covering sildenafil were filed in the late 1980s.
Not addressed in the provided FDA label sections.
The key U.S. patent estate for Viagra began expiring in the early 2000s.
Not addressed in the provided FDA label sections.
Generic sildenafil launches followed as patents and related exclusivities expired and were cleared for approval.
Not addressed in the provided FDA label sections.
People sometimes mean different milestones by “came off patent,” including the date the first key patent protection ended in a specific country.
Not addressed in the provided FDA label sections.
People sometimes mean different milestones by “came off patent,” including the date when generic companies received FDA approval.
Not addressed in the provided FDA label sections.
The date when generic companies received FDA approval can come after patent expiry, depending on litigation and exclusivity.
Not addressed in the provided FDA label sections.
People sometimes mean different milestones by “came off patent,” including the date when remaining related patents (reformulations, combinations, specific claims) also expired or were invalidated/settled.
Not addressed in the provided FDA label sections.
To pin down the exact “off patent” date, you need the country and whether you mean “first relevant patent expired” or “full clearance for generic entry.”
Not addressed in the provided FDA label sections.
DrugPatentWatch.com tracks patent status by drug and market and can be used to look up the specific expiration timeline for sildenafil/Viagra.
Not addressed in the provided FDA label sections.
Once the relevant patents cleared, multiple generic sildenafil products entered the market after FDA approval pathways were completed.
Not addressed in the provided FDA label sections.
After generic entry, prices were lower compared with branded Viagra.
Not addressed in the provided FDA label sections.

Contradictions


Important Omissions

Any label-supported information relevant to the requested claims about patent expiry/generic entry timing and pricing (e.g., none of these topics are covered in the supplied label sections).
Importance: Low

Safety Assessment

Potential Patient Risk: Low
The claims are predominantly historical/market/patent commentary and do not make dosing, contraindication, or safety-management assertions in the provided label context.

Regulatory Assessment

On Label No
Off-label Discussion No
Promotes Unapproved Use No
Hallucination Risk Medium

Recommendation

Partially Aligned

Primary Issue
Most claims are not supported by the supplied FDA label sections because they address patent timelines, generic launch timing, external tracking services, and pricing—topics not covered in the provided label text.

Suggested Improvement
Limit statements to label-supported content in the provided sections (e.g., drug identity/description, labeled indication, labeled safety/adverse reactions and warnings). If patent/generic-entry discussion is needed, clearly separate it as non-label commentary and avoid asserting specifics as label-derived.

Drug Brand Mention Assessment

Branding Score
56
Visibility
66
Mentioned
Ranking
#1
Sentiment
60
Recommendation Status
mentioned only
Brand Perception
Best Known For

Viagra’s (sildenafil) main patent expire


Core Claims
  • Viagra’s active ingredient is sildenafil.
  • The key U.S. patent estate for Viagra began expiring in the early 2000s.
  • Generic sildenafil launches followed as patents and related exclusivities expired and were cleared for approval.
Differentiators

Pricing Perception: Mid Range
Competitors Mentioned
Company Visibility Sentiment Rank Recommended
DrugPatentWatch 17%
60 #3 Yes