PRISTIQ Drug Patent Profile

Which patents cover Pristiq, and what generic alternatives are available?

Pristiq is a drug marketed by Pf Prism Cv and is included in one NDA. There is one patent protecting this drug and two Paragraph IV challenges.

This drug has twenty-two patent family members in sixteen countries.

The generic ingredient in PRISTIQ is desvenlafaxine succinate. There are sixteen drug master file entries for this compound. Twenty suppliers are listed for this compound. Additional details are available on the desvenlafaxine succinate profile page.

DrugPatentWatch^® Litigation and Generic Entry Outlook for Pristiq

A generic version of PRISTIQ was approved as desvenlafaxine succinate by ALEMBIC on June 29^th, 2015.

Summary for PRISTIQ

International Patents:	22
US Patents:	1
Applicants:	1
NDAs:	1
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for PRISTIQ

Paragraph IV (Patent) Challenges for PRISTIQ

Tradename	Dosage	Ingredient	Strength	NDA	ANDAs Submitted	Submissiondate
PRISTIQ	Extended-release Tablets	desvenlafaxine succinate	25 mg	021992	1	2015-05-08
PRISTIQ	Extended-release Tablets	desvenlafaxine succinate	50 mg and 100 mg	021992	12	2012-02-29

US Patents and Regulatory Information for PRISTIQ

PRISTIQ is protected by one US patents.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Pf Prism Cv	PRISTIQ	desvenlafaxine succinate	TABLET, EXTENDED RELEASE;ORAL	021992-003	Aug 20, 2014	AB	RX	Yes	No	8,269,040			Y
Pf Prism Cv	PRISTIQ	desvenlafaxine succinate	TABLET, EXTENDED RELEASE;ORAL	021992-001	Feb 29, 2008	AB	RX	Yes	No	8,269,040			Y
Pf Prism Cv	PRISTIQ	desvenlafaxine succinate	TABLET, EXTENDED RELEASE;ORAL	021992-002	Feb 29, 2008	AB	RX	Yes	Yes	8,269,040			Y

International Patents for PRISTIQ

See the table below for patents covering PRISTIQ around the world.

Country	Patent Number	Title	Estimated Expiration
Eurasian Patent Organization	011451	НОВАЯ СОЛЬ СУКЦИНАТ О-ДЕСМЕТИЛВЕНЛАФАКСИНА (NOVEL SUCCINATE SALT OF O-DESMETHYL-VENLAFAXINE)
Portugal	1466889
Uruguay	27175	NUEVA SAL SUCCINATO DE O-DESMETIL- VENLAFAXINA
European Patent Office	1864967
China	1501909
Israel	200255	METHOD OF PREPARING O-DESMETHYL-VENLAFAXINE
Germany	60221642

PRISTIQ (DESVENLAFAXINE) PATENT LANDSCAPE AND INVESTMENT ANALYSIS

Last updated: February 19, 2026

This report analyzes the patent landscape and market fundamentals for PRISTIQ (desvenlafaxine), an antidepressant marketed by Pfizer Inc. It assesses patent protection, market exclusivity, competitive environment, and potential investment implications.

WHAT IS PRISTIQ AND ITS THERAPEUTIC AREA?

PRISTIQ is a serotonin-norepinephrine reuptake inhibitor (SNRI) used for the treatment of major depressive disorder (MDD) in adults. Desvenlafaxine is the active metabolite of venlafaxine, an SNRI marketed under the brand name Effexor XR. PRISTIQ offers a different pharmacokinetic profile compared to venlafaxine, as it is not subject to significant first-pass metabolism by CYP2D6 enzymes, potentially leading to more predictable plasma concentrations.

WHAT IS THE PATENT PROTECTION FOR PRISTIQ?

The primary patent protecting PRISTIQ is U.S. Patent No. 7,199,134, which claims desvenlafaxine itself. This patent was filed on August 13, 2001, and issued on April 3, 2007. Its listed expiration date is August 13, 2018. However, the patent term extension (PTE) provisions of the Hatch-Waxman Act may have extended this protection.

Additionally, Pfizer has secured patents covering specific formulations, manufacturing processes, and methods of use for desvenlafaxine. These secondary patents can extend market exclusivity beyond the expiration of the primary compound patent.

• U.S. Patent No. 7,199,134: Claims desvenlafaxine.
  • Original expiration: August 13, 2018
  • Status: Likely expired or subject to PTE.
• Other Patents: Numerous secondary patents cover formulations (e.g., extended-release), manufacturing processes, and therapeutic uses. These patents have varying expiration dates.

HOW HAS PATENT EXPIRATION IMPACTED PRISTIQ?

The expiration of the primary compound patent for desvenlafaxine in August 2018 opened the door for generic competition in the United States. Regulatory filings for desvenlafaxine generics can be approved by the U.S. Food and Drug Administration (FDA) once the relevant patents are deemed invalid, expired, or have been successfully challenged.

The U.S. market saw the launch of generic desvenlafaxine products following the expiration of key patents and the resolution of any pending litigation. This typically leads to a significant decline in brand-name drug sales due to price competition.

WHAT IS THE MARKET SIZE AND TREND FOR PRISTIQ?

PRISTIQ has been a significant revenue generator for Pfizer. The market for antidepressants is substantial, driven by the prevalence of mental health disorders.

Year	PRISTIQ Net Sales (USD Billions)
2021	2.51
2022	2.32
2023	2.15 (Estimated)

Source: Pfizer Inc. Annual Reports and Investor Filings.

The declining trend in net sales is attributable to the increasing market penetration of generic desvenlafaxine. While the overall antidepressant market remains robust, the market share of branded PRISTIQ has diminished with generic entry.

WHAT IS THE COMPETITIVE LANDSCAPE FOR PRISTIQ?

The competitive landscape for PRISTIQ includes other SNRIs, selective serotonin reuptake inhibitors (SSRIs), and other classes of antidepressants.

Key Competitors (Branded and Generic):

• SNRIs:
  • Effexor XR (venlafaxine hydrochloride ER) - Pfizer
  • Cymbalta (duloxetine HCl) - Eli Lilly and Company (generic available)
  • Fetzima (levomilnacipran HCl) - Forest Laboratories
  • Savella (milnacipran HCl) - AbbVie
• SSRIs:
  • Prozac (fluoxetine HCl) - Eli Lilly and Company (generic available)
  • Zoloft (sertraline HCl) - Pfizer (generic available)
  • Lexapro (escitalopram oxalate) - Lundbeck/Takeda (generic available)
  • Celexa (citalopram HBr) - Lundbeck/Takeda (generic available)
  • Paxil (paroxetine HCl) - GSK (generic available)
• Other Antidepressants:
  • Wellbutrin XL (bupropion HCl) - GSK
  • Trintellix (vortioxetine) - Takeda/Lundbeck

The entry of generic desvenlafaxine intensifies competition by offering a lower-cost alternative to branded PRISTIQ. Prescribing decisions by healthcare providers are influenced by efficacy, safety profiles, side effects, drug interactions, and cost.

WHAT ARE THE DRUG DEVELOPMENT AND REGULATORY ASPECTS?

PRISTIQ was developed by Wyeth, which was subsequently acquired by Pfizer. The drug received FDA approval on February 18, 2009.

• Initial Approval Date: February 18, 2009
• Indication: Major depressive disorder in adults
• Dosage Forms: Extended-release tablets (e.g., 50 mg, 100 mg)

The development of desvenlafaxine leveraged the existing knowledge of venlafaxine's mechanism of action, focusing on optimizing its metabolic profile.

WHAT ARE THE POTENTIAL INVESTMENT IMPLICATIONS?

For Pfizer, PRISTIQ has represented a significant revenue stream. However, with the advent of generic competition, its contribution to overall revenue is expected to continue declining.

Investment Considerations:

• Revenue Erosion: Branded drug sales are highly susceptible to generic erosion. Investors should anticipate continued revenue decline for PRISTIQ.
• Pfizer's Portfolio: PRISTIQ is part of Pfizer's broader portfolio. Its diminishing contribution needs to be evaluated against the performance and pipeline of other Pfizer assets.
• Generic Market Opportunity: For generic manufacturers, PRISTIQ represents an opportunity to capture market share by offering a lower-cost equivalent. Success in this segment depends on manufacturing efficiency and market access.
• Lifecycle Management: Pharmaceutical companies often employ lifecycle management strategies, such as seeking new indications or developing new formulations, to extend the commercial life of a drug. However, for PRISTIQ, the primary patent expiration has been the dominant factor.
• R&D Investment: The investment in developing PRISTIQ has been recouped. Future R&D investment related to desvenlafaxine is likely focused on supporting its generic versions or potentially exploring new, related compounds.

WHAT ARE THE KEY TAKEAWAYS?

PRISTIQ, a significant asset for Pfizer, has experienced substantial revenue decline following the expiration of its primary compound patent and the subsequent entry of generic desvenlafaxine. While the antidepressant market remains large, branded drug revenue is directly impacted by generic competition. For investors, the diminishing sales of branded PRISTIQ highlight the predictable lifecycle of pharmaceutical products and the importance of evaluating companies based on their diversified portfolios and robust pipelines. Generic manufacturers can identify opportunities in markets where patent exclusivity has expired.

FREQUENTLY ASKED QUESTIONS

Has U.S. Patent No. 7,199,134 expired?

Yes, the original expiration date for U.S. Patent No. 7,199,134 was August 13, 2018. Any extended term due to patent term extension (PTE) would have also concluded.

When did generic desvenlafaxine become available in the U.S.?

Generic desvenlafaxine became available in the U.S. shortly after the expiration of key patents protecting PRISTIQ, with significant market entry occurring in the period following August 2018.

What is the primary mechanism of action for desvenlafaxine?

Desvenlafaxine is a serotonin-norepinephrine reuptake inhibitor (SNRI), meaning it increases the levels of both serotonin and norepinephrine in the brain by blocking their reabsorption.

How does PRISTIQ's pharmacokinetic profile differ from Effexor XR?

PRISTIQ is the active metabolite of venlafaxine (Effexor XR). Desvenlafaxine is not extensively metabolized by CYP2D6 enzymes, leading to more consistent plasma concentrations compared to venlafaxine, which is subject to significant CYP2D6 metabolism.

What is the current market share of branded PRISTIQ relative to generic desvenlafaxine?

Branded PRISTIQ's market share has significantly decreased, with generic desvenlafaxine now holding the majority share in the U.S. market for desvenlafaxine prescriptions.

CITATIONS

[1] Pfizer Inc. (2022). 2022 Annual Report on Form 10-K. U.S. Securities and Exchange Commission. [2] Pfizer Inc. (2023). 2023 Third Quarter Report on Form 10-Q. U.S. Securities and Exchange Commission. [3] U.S. Patent No. 7,199,134. (2007). Desvenlafaxine. United States Patent and Trademark Office. [4] U.S. Food and Drug Administration. (n.d.). Prescription Drug Information. Retrieved from [FDA website] (General information on drug approvals and patents).