CLINICAL TRIALS PROFILE FOR PRISTIQ

All Clinical Trials for Pristiq

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00401245 ↗	The Effect Of Dose Titration And Dose Tapering On The Tolerability Of DVS SR In Women With Vasomotor Symptoms	Completed	Pfizer	Phase 3	2006-12-01	Desvenlafaxine succinate (DVS SR) is a serotonin and norepinephrine reuptake inhibitor (SNRI). It is a nonhormonal option for the treatment of Vasomotor Symptoms (VMS) associated with menopause. Nausea is the most common adverse event that is observed in clinical studies and is the main reason for discontinuation during the first week of therapy. Other adverse events (headache, nausea, and dizziness) associated with DVS SR have been noted to occur when subjects abruptly discontinue the medication. The purpose of this study is to evaluate several titration and tapering regimens of DVS SR to ensure a better tolerability profile at the start and completion of treatment. In addition, this study will provide a long posttreatment follow-up to assess any symptoms after treatment is discontinued.
NCT00824291 ↗	Study Evaluating Desvenlafaxine Succinate Sustained Release In Outpatients With Major Depressive Disorder	Completed	Wyeth is now a wholly owned subsidiary of Pfizer	Phase 3	2009-02-01	This is a multicenter study to assess the health and well-being in subjects who are outpatients with major depressive disorder that take desvenlafaxine succinate sustained release (DVS SR) or placebo for 12 weeks.
NCT00887224 ↗	Relapse Prevention Study Of Desvenlafaxine Succinate Sustained Release In Outpatients With Major Depressive Disorder	Completed	Pfizer	Phase 3	2009-06-01	The primary purpose of this study is to compare the long-term efficacy and safety of desvenlafaxine succinate sustained release versus placebo in adults with Major Depressive Disorder, using a randomized withdrawal design. Randomized withdrawal means that after receiving desvenlafaxine succinate sustained release for a predetermined period of time, subjects will be selected by chance to either continue receiving the study drug or to be withdrawn from the study drug and receive placebo for the remainder of their participation in the trial. Subjects will not know to which group they have been assigned. The study consists of an up to 14-day screening period followed by an 8-week open-label period in which subjects will knowingly receive 50 mg/day of desvenlafaxine succinate sustained release. Subjects who do not respond to treatment, demonstrating no significant change in their depressive symptoms, will be withdrawn from participation at the end of this period. Responding subjects will receive an additional 3 months of open-label desvenlafaxine succinate sustained release at the same dose. Subjects with stable response to treatment at the conclusion of this 3 month period will be randomized to either desvenlafaxine succinate sustained release at 50 mg/day or placebo in a blinded manner for an additional 6 months or until symptoms of depression return. Following discontinuation at any point after enrollment in the study, subjects will receive two weeks of follow-up monitoring, including one week of blinded taper with 25 mg/day of desvenlafaxine succinate sustained release treatment for any subjects who have been taking desvenlafaxine succinate sustained release prior to discontinuation. Subjects assigned to placebo will receive a blinded placebo taper. Following taper, subjects will be evaluated for one additional week to monitor safety.

Clinical Trial Conditions for Pristiq

Condition Name

Condition Name for Pristiq
Intervention	Trials
Major Depressive Disorder	10
Dysthymic Disorder	2
Vasomotor Symptoms	2

Condition MeSH

Condition MeSH for Pristiq
Intervention	Trials
Depressive Disorder	16
Depression	16
Depressive Disorder, Major	14

Clinical Trial Locations for Pristiq

Trials by Country

Trials by Country for Pristiq
Location	Trials
United States	93
Canada	20
Colombia	4
Romania	2
Poland	2

Trials by US State

Trials by US State for Pristiq
Location	Trials
New York	6
New Jersey	5
Ohio	5
Illinois	4
Florida	4

Clinical Trial Progress for Pristiq

Clinical Trial Phase

Clinical Trial Phase for Pristiq
Clinical Trial Phase	Trials
Phase 4	10
Phase 3	4
Phase 2/Phase 3	1

Clinical Trial Status

Clinical Trial Status for Pristiq
Clinical Trial Phase	Trials
Completed	16
Terminated	3
Unknown status	3

Clinical Trial Sponsors for Pristiq

Sponsor Name

Sponsor Name for Pristiq
Sponsor	Trials
Pfizer	10
Luye Pharma Group Ltd.	4
Wyeth is now a wholly owned subsidiary of Pfizer	2

Sponsor Type

Sponsor Type for Pristiq
Sponsor	Trials
Other	20
Industry	16
NIH	1

Clinical Trials and Efficacy of PRISTIQ

Introduction to PRISTIQ

PRISTIQ, also known as desvenlafaxine succinate, is an extended-release tablet indicated for the symptomatic relief of major depressive disorder (MDD). Here, we will delve into the clinical trials that established its efficacy, its market analysis, and projections.

Clinical Trials Overview

The efficacy of PRISTIQ was established through several clinical trials.

Randomized, Double-Blind, Placebo-Controlled Studies

Four 8-week, randomized, double-blind, placebo-controlled, fixed-dose studies were conducted to evaluate the efficacy of PRISTIQ in adult outpatients with MDD. These studies involved various doses of PRISTIQ, ranging from 50 mg to 400 mg per day. The primary outcome measures included the 17-item Hamilton Rating Scale for Depression (HAM-D17) total score and the Clinical Global Impressions Scale - Improvement (CGI-I)[1].

• Dose Efficacy: Patients received either 50 mg, 100 mg, 200 mg, or 400 mg of PRISTIQ once daily. The results showed that PRISTIQ was superior to placebo in improving the HAM-D17 total score in all four studies and in overall improvement as measured by the CGI-I in three of the four studies[1].
• Dose Comparison: Studies comparing 50 mg and 100 mg doses did not suggest a greater effect with the higher dose. However, adverse reactions and discontinuations were more frequent at higher doses[1].

Long-Term Efficacy

In addition to the short-term efficacy, PRISTIQ's ability to maintain an antidepressant response was evaluated in a placebo-controlled trial. This trial demonstrated that PRISTIQ could maintain an antidepressant response for up to 26 weeks following an initial 20 weeks of acute, open-label treatment[3].

Postmarketing Study

A postmarketing study evaluated the efficacy of PRISTIQ at a dose lower than 50 mg per day. This 8-week, multicenter, randomized, double-blind, placebo-controlled study found that the 50 mg dose was superior to placebo, as measured by the mean change from baseline on the HAM-D17. However, the 25 mg dose was not superior to placebo[1].

Safety and Tolerability

PRISTIQ has been evaluated for its safety and tolerability in various studies.

Adverse Reactions

Common adverse reactions include increases in blood pressure, particularly at higher doses. Patients with pre-existing hypertension should have their blood pressure controlled before treatment with PRISTIQ, and regular monitoring of blood pressure is recommended[3].

Discontinuation Rates

Pooled analysis of 8-week studies showed low discontinuation rates for PRISTIQ 50 mg, comparable to placebo (4.1% vs 3.8%)[4].

Sexual Dysfunction

The incidence of sexual dysfunction was low in patients taking PRISTIQ 50 mg, with no significant difference compared to placebo[4].

Weight Changes

There was no clinical difference in weight gain between PRISTIQ 50 mg and placebo in 8-week studies[4].

Market Analysis

Patent Loss and Generic Entry

In 2017, Pfizer faced a significant challenge with the loss of the patent for PRISTIQ, leading to the entry of generic versions of desvenlafaxine extended-release tablets. Companies like Mylan, Lupin, Sandoz, and Teva’s Actavis unit launched their generic versions, impacting Pfizer’s revenue. Despite this, PRISTIQ had generated $853 million in revenue for the 12 months through January 2017[2].

Historical Context

PRISTIQ was developed by Wyeth before its merger with Pfizer in 2009. It was launched to protect Pfizer's sales from the patent loss of another antidepressant, Effexor[2].

Market Projections

Impact of Generic Competition

The entry of generic competitors has significantly reduced the market share and revenue of the branded version of PRISTIQ. This trend is expected to continue, with generic versions capturing a larger portion of the market.

Overall Market Trends

The antidepressant market is highly competitive, with multiple drugs available for the treatment of MDD. The market is driven by the increasing prevalence of depression, advancements in treatment options, and the availability of generic alternatives.

Financial Impact on Pfizer

Revenue Guidance

While Pfizer's overall revenue guidance for 2025 is robust, with projected revenues ranging from $61.0 to $64.0 billion, the specific impact of PRISTIQ's generic competition on Pfizer's financials is significant. The loss of exclusivity for PRISTIQ contributes to the challenges Pfizer faces in maintaining revenue from this product[5].

Key Takeaways

• Efficacy: PRISTIQ has been shown to be effective in treating MDD in multiple clinical trials.
• Safety and Tolerability: The drug has a favorable safety profile, although it requires monitoring of blood pressure and has higher discontinuation rates at higher doses.
• Market Impact: The entry of generic versions has significantly impacted the market share and revenue of the branded version.
• Financial Projections: Pfizer's overall financial health is robust, but the loss of exclusivity for PRISTIQ affects its revenue from this product.

FAQs

1. What is PRISTIQ used for? PRISTIQ is used for the symptomatic relief of major depressive disorder (MDD).

2. What were the key findings of the clinical trials for PRISTIQ? The clinical trials showed that PRISTIQ was superior to placebo in improving the HAM-D17 total score and overall improvement as measured by the CGI-I in patients with MDD.

3. What are the common adverse reactions associated with PRISTIQ? Common adverse reactions include increases in blood pressure, particularly at higher doses, and a higher incidence of systolic orthostatic hypotension in elderly patients.

4. How has the entry of generic versions affected the market for PRISTIQ? The entry of generic versions has significantly reduced the market share and revenue of the branded version of PRISTIQ.

5. What is the current financial outlook for Pfizer regarding PRISTIQ? Pfizer's overall revenue guidance is robust, but the loss of exclusivity for PRISTIQ contributes to the challenges in maintaining revenue from this product.

Sources

1. Pfizer Medical Information: PRISTIQ® (desvenlafaxine succinate) Clinical Studies - US.
2. FiercePharma: Pfizer faces first 2017 patent loss as Pristiq generics crash the party.
3. E-lactancia: PRISTIQ® (desvenlafaxine) Product Monograph.
4. PfizerPro: Tolerability | PRISTIQ® (desvenlafaxine) 50 mg | Safety Info.
5. Pfizer: Pfizer Provides Full-Year 2025 Guidance and Reaffirms Full-Year 2024 Guidance.