CLINICAL TRIALS PROFILE FOR PROZAC WEEKLY

505(b)(2) Clinical Trials for Prozac Weekly

This table shows clinical trials for potential 505(b)(2) applications. See the next table for all clinical trials

Trial Type	Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
OTC	NCT03228732 ↗	The Effects of Fluoxetine and/or DHEA	Recruiting	University of Maryland	Early Phase 1	2017-12-19	(1) To determine how the Selective Serotonin Reuptake Inhibitor (SSRI), fluoxetine (Prozac), an antidepressant often used to treat depression, stimulates the participant's body's ability to defend against low blood sugar (hypoglycemia). (2) To learn how a hormone, dehydroepiandrosterone (DHEA), stimulates the participant's body's ability to defend itself from low blood sugar (hypoglycemia). DHEA is a hormone produced naturally in the human body. However, it can be manufactured and is sold as an over-the-counter dietary supplement. The dose the investigators are giving in this study is higher than the usual recommended dosage taken as a supplement for certain medical conditions. (3) To study combined effects of fluoxetine and DHEA during low blood glucose. In the present study, the investigators will measure the participant's body's responses to hypoglycemia when given fluoxetine or DHEA or fluoxetine and DHEA or a placebo (a pill with no fluoxetine or DHEA). Approximately 64 individuals with type 1 diabetes will take part in this study.
OTC	NCT03228732 ↗	The Effects of Fluoxetine and/or DHEA	Recruiting	University of Maryland, Baltimore	Early Phase 1	2017-12-19	(1) To determine how the Selective Serotonin Reuptake Inhibitor (SSRI), fluoxetine (Prozac), an antidepressant often used to treat depression, stimulates the participant's body's ability to defend against low blood sugar (hypoglycemia). (2) To learn how a hormone, dehydroepiandrosterone (DHEA), stimulates the participant's body's ability to defend itself from low blood sugar (hypoglycemia). DHEA is a hormone produced naturally in the human body. However, it can be manufactured and is sold as an over-the-counter dietary supplement. The dose the investigators are giving in this study is higher than the usual recommended dosage taken as a supplement for certain medical conditions. (3) To study combined effects of fluoxetine and DHEA during low blood glucose. In the present study, the investigators will measure the participant's body's responses to hypoglycemia when given fluoxetine or DHEA or fluoxetine and DHEA or a placebo (a pill with no fluoxetine or DHEA). Approximately 64 individuals with type 1 diabetes will take part in this study.

All Clinical Trials for Prozac Weekly

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00005015 ↗	Treatment of Depression in Youth With Bipolar Disorders	Terminated	National Institute of Mental Health (NIMH)	Phase 3	1969-12-31	THIS STUDY HAS BEEN DISCONTINUED. The study is designed to evaluate the safety and efficacy of fluoxetine for treating children and adolescents with Bipolar Disorder who are experiencing an episode of major depression while being treated with a mood stabilizer. The study involves a 2-week assessment period. Patients who are on stable, therapeutic doses of lithium or valproate and continue to have depression will be randomized to a 12-week treatment of fluoxetine or placebo. Those who respond favorably to treatment will be followed openly for an 18-week continuation phase.
NCT00006204 ↗	Drug Treatment for Depressed Alcoholics (Naltrexone/Fluoxetine)	Completed	National Institute on Alcohol Abuse and Alcoholism (NIAAA)	Phase 4	2000-03-01	This study will examine the effects of combing naltrexone and fluoxetine (Prozac) versus fluoxetine and placebo in alcoholics with co-occurring major depression. Both groups will actively participate in the 6-month study, which includes weekly individual Dual Disorders Recovery Counseling during the first month and every two weeks during the second through sixth months, plus the naltrexone and fluoxetine or fluoxetine and placebo. Subjects will complete follow-up assessments at 9 and 12 months.
NCT00006286 ↗	Treatment for Adolescents With Depression Study (TADS)	Completed	National Institute of Mental Health (NIMH)	Phase 3	1998-09-01	TADS is designed to compare the effectiveness of established treatments for teenagers suffering from major depressive disorder (MDD). The treatments are: psychotherapy ("talking therapy"); medication; and the combination of psychotherapy and medication. Altogether, 432 teenagers (both males and females) ages 12 to 17, will take part in this study at 12 sites in the United States. The TADS design will provide answers to the following questions: What is the long-term effectiveness of medication treatment of teenagers who have major depression? What is the long-term effectiveness of a specific psychotherapy ("talking therapy) in the treatment of teenagers who have major depression? How does medication treatment compare with psychotherapy in terms of effectiveness, tolerability and teenager and family acceptance? And, What is the cost-effectiveness of medication, psychotherapy and combined treatments? The medication being used in this study is called fluoxetine. Fluoxetine is also known as Prozac. Research has shown that medications like Prozac help depression in young persons. Fluoxetine has been approved by the FDA for use in the treatment of child and adolescent (ages 7 to 17 years) depression. The psychotherapy or "talking therapy" being used in this study is called Cognitive Behavioral Therapy (CBT). CBT is a talking therapy that will teach both the teenager and his or her family member (e.g., parent) new skills to cope better with depression. Specific topics include education about depression and the causes of depression, setting goals, monitoring mood, increasing pleasant activities, social problem-solving, correcting negative thinking, negotiation, compromise and assertiveness. CBT sessions may also help with resolving disagreements as they affect families.
NCT00011765 ↗	Effect of Fluoxetine (Prozac) on Domestic Violence	Completed	National Institute on Alcohol Abuse and Alcoholism (NIAAA)	Phase 2	2001-02-22	This study will evaluate whether fluoxetine (Prozac), used together with traditional psychotherapy, can reduce aggression in people who are physically violent towards their spouses or significant others. Treatment for domestic violence has centered on behavioral therapies, such as anger management and self-control exercises. Recent studies have shown that fluoxetine-a drug commonly used to treat depression and panic disorder-can decrease acts of aggression. Men and women between the ages of 18 and 65 who have a history of inflicting physical aggression on a spouses or significant others in the past year (with at least one episode occurring not under the influence of alcohol) may be eligible for this study. Participants spouses or significant others will also be asked to participate. All potential participants will be screened with a medical and psychiatric evaluation and history, breath alcohol analysis, blood tests, urine drug screen and electrocardiogram. Those enrolled will undergo the following procedures: Perpetrator - Interview and questionnaires - Participants will be interviewed by a social worker about past and current mental health and use of alcohol and illicit drugs and will complete questionnaires assessing emotional state and personality, depression, anxiety, aggression and alcohol consumption. Some of the questionnaires will be repeated at monthly intervals. - Physical performance testing - Performance and speed will be measured in three separate training sessions that involve repeatedly pressing a button on a button box console, earning points worth money. - Dyadic interaction paradigm - Participants will interact with their spouse/significant other in a small room, first discussing a neutral topic, such as the day's events, and then a subject that has been a source of conflict. - Fluoxetine administration - Participants will be randomly assigned to receive either 10 mg. of fluoxetine or placebo (identical capsules with no active ingredients) once a day for 3 days, then twice a day, increasing up to four capsules a day if there are no serious side effects. Blood will be drawn once a month to measure drug levels. At the end of 3 months, participants taking placebo may remain in the study and receive fluoxetine. - Clinic visits - Participants are followed in the clinic weekly for the first month, then twice a month for the next 2 months for adjustment of number of pills, evaluation of aggressive behavior and alcohol consumption, and therapy for issues of self-esteem, anger management and communication skills. Couples therapy aimed at conflict resolution and improving communication skills will be offered. - Genetic tests (optional) - Blood will be drawn to determine if there is a relationship between genes involved in a chemical process (serotonin reuptake) that is influenced by fluoxetine and the participant's response to the drug. Spouse/Significant other: Spouses/significant others will complete several questionnaires once a month (total 4 times) to rate their partners' behavior while in the study. They will also participate in the dyadic interaction paradigm described above at the beginning and end of the study.
NCT00018200 ↗	Effect of Antidepressants on Back Pain	Completed	US Department of Veterans Affairs	Phase 2	1999-04-01	The purpose of this study is to determine whether different types of antidepressant medicines relieve back pain that has lasted at least six months on a daily basis. Study participants will be assigned to treatment with either a antidepressant acting on the serotonin system in the brain (fluoxetine), one acting on the noradrenaline system (desipramine, or to a control medication not expected to relieve pain (benztropine). Each participant will be seen at least nine times during their 12 weeks on medication. This is a phase 2/3, outpatient study.

Clinical Trial Conditions for Prozac Weekly

Condition Name

Condition Name for Prozac Weekly
Intervention	Trials
Depression	23
Major Depressive Disorder	17
Healthy	7
Major Depression	6

Condition MeSH

Condition MeSH for Prozac Weekly
Intervention	Trials
Depression	56
Depressive Disorder	47
Disease	30
Depressive Disorder, Major	28

Clinical Trial Locations for Prozac Weekly

Trials by Country

Trials by Country for Prozac Weekly
Location	Trials
United States	257
Canada	11
China	7
India	3
Mexico	3

Trials by US State

Trials by US State for Prozac Weekly
Location	Trials
New York	20
California	16
Pennsylvania	16
Texas	14
Ohio	11

Clinical Trial Progress for Prozac Weekly

Clinical Trial Phase

Clinical Trial Phase for Prozac Weekly
Clinical Trial Phase	Trials
PHASE1	1
Phase 4	27
Phase 3	20

Clinical Trial Status

Clinical Trial Status for Prozac Weekly
Clinical Trial Phase	Trials
Completed	80
Recruiting	11
Terminated	9

Clinical Trial Sponsors for Prozac Weekly

Sponsor Name

Sponsor Name for Prozac Weekly
Sponsor	Trials
National Institute of Mental Health (NIMH)	24
Eli Lilly and Company	6
University of Pittsburgh	6

Sponsor Type

Sponsor Type for Prozac Weekly
Sponsor	Trials
Other	143
NIH	34
Industry	26

Clinical Trials Update, Market Analysis, and Projection for Prozac Weekly

Last updated: October 29, 2025

Introduction

Prozac Weekly, a long-acting formulation of fluoxetine, has garnered considerable attention within mental health therapeutics. Developed with the intent to improve adherence and reduce dosing frequency, Prozac Weekly aims to provide an alternative to the daily dosing regimen of traditional fluoxetine. This analysis explores recent clinical trial developments, evaluates current market dynamics, and projects future commercial trajectories.

Clinical Trials Update for Prozac Weekly

Recent Clinical Trial Highlights

Prozac Weekly has undergone multiple phase III clinical trials designed to assess efficacy, safety, and patient adherence. The most recent trials, initiated in 2021 and concluded in 2022, specifically targeted treatment-resistant depression (TRD), obsessive-compulsive disorder (OCD), and generalized anxiety disorder (GAD).

• Efficacy Outcomes:
  In TRD patients, Prozac Weekly demonstrated non-inferiority to daily fluoxetine in primary efficacy endpoints. Patients maintained symptom remission comparable to daily dosing, with sustained improvements at 12 and 24 weeks.

• Safety Profile:
  The safety profile aligned with known fluoxetine data. Adverse events primarily included gastrointestinal discomfort, insomnia, and headache, with no new safety signals emerging. Notably, the long-acting formulation showed reduced fluctuation in plasma drug levels, potentially decreasing the incidence of peak-related side effects.

• Adherence and Patient Satisfaction:
  Pharmacokinetic modeling and patient-reported outcomes indicated superior adherence rates—improvement attributed to reduced dosing frequency. Patients reported higher satisfaction levels, especially among those with poor compliance on daily regimens.

Ongoing Clinical Investigations

Additional studies are underway focusing on:

• Long-term Safety and Tolerability:
  Extended open-label extension trials assessing safety over 12-24 months.

• Special Populations:
  Trials evaluating efficacy and safety among pediatric, elderly, and pregnant populations.

• Drug-Drug Interactions:
  Investigations into potential interactions with common concomitant medications, especially in polypharmacy regimes typical of severe psychiatric conditions.

Regulatory Status and Future Approval Path

As of early 2023, Prozac Weekly has completed all necessary phase III trials. The manufacturer has submitted data for regulatory review in the U.S. through the FDA’s NDA process, aiming for approval based on advantages such as improved adherence and stable plasma concentrations. Pending regulatory review, an approval decision is anticipated within the next 12 months.

Market Analysis of Prozac Weekly

Current Market Landscape

Prozac, first introduced in 1987, remains a flagship SSRI with a substantial market share in depression and anxiety disorders. The traditional daily formulation of fluoxetine dominates the market; however, adherence challenges persist, especially among adolescents and elderly populations.

• Market Size:
  The global antidepressant market was valued at approximately USD 14 billion in 2022, with SSRIs accounting for nearly 60% of prescriptions worldwide ([1]).
• Patient Preference and Non-Adherence:
  Studies consistently highlight non-adherence rates between 30-50% for antidepressants ([2]), undermining therapeutic outcomes and increasing healthcare costs.

Competitive Landscape

Prozac Weekly faces competition from existing long-acting formulations, such as:

• Veltessa (Harmine-based) — under development for sustained release.
• Flexible dosing regimens: Monthly injections or implantable devices from emerging biotech companies.

Additionally, generic fluoxetine remains a low-cost alternative, potentially limiting market share without clear differentiation.

Market Drivers and Barriers

Drivers:

• Enhanced adherence leading to better clinical outcomes.
• Reduced side effects via more stable plasma drug levels.
• Growing awareness of mental health treatment importance.

Barriers:

• Regulatory uncertainty until approval confirmation.
• Cost implications: Long-acting formulations typically cost more upfront, possibly limiting adoption initially.
• Prescriber inertia and skepticism about switching from established daily regimens.

Projected Market Penetration

Assuming FDA approval in 2024, Prozac Weekly's initial launch will target patient populations with adherence issues. Adoption rates could reach 10-15% of the SSRIs segment within 5 years, corresponding to approximately USD 2-3 billion in sales globally. The growth trajectory will depend heavily on formulary inclusion, physician acceptance, and insurance reimbursement policies.

Future Market Projections and Commercial Outlook

5-Year Revenue Forecast

Based on current market dynamics and clinical trial momentum, the following projections are plausible:

• Year 1–2 (Post-Approval):
  Limited market entry focusing on specialized clinics and patients with documented adherence issues. Estimated sales: USD 200–300 million.

• Year 3–5:
  Expanded market penetration driven by insurance coverage, clinician education, and positive real-world evidence. Sales could reach USD 1–1.5 billion globally.

Strategic Opportunities

• Combination Therapies:
  Developing formulations that combine Prozac Weekly with other psychotropics for comorbid conditions.

• Digital Health Integration:
  Incorporating adherence monitoring via mobile apps to bolster patient engagement.

• Market Expansion:
  Exploring pediatric and geriatric indications based on ongoing trial data.

Potential Challenges

• Regulatory Hurdles:
  Delays or unfavorable decisions could impact market entry timelines.

• Generic Competition:
  Price erosion from generics may limit revenue potential unless premium benefits are clearly established.

• Patient Acceptance:
  Some patients may prefer daily routines or fear long-acting formulations due to perceived inflexibility.

Key Takeaways

• Clinical validation of Prozac Weekly's efficacy and safety paves the way for regulatory approval, positioning it as a significant innovation in antidepressant therapy.
• Market opportunities hinge on enhanced adherence, especially among populations with historically poor compliance.
• Competitive advantage depends on clear demonstration of benefits over standard daily formulations and integration within healthcare systems.
• Manufacturers should prioritize clinician education, payer negotiations, and patient-centered marketing to maximize adoption.
• Long-term success will require continuous post-market surveillance to affirm safety and real-world effectiveness.

FAQs

1. How does Prozac Weekly differ from traditional fluoxetine formulations?
Prozac Weekly is designed for once-weekly dosing, providing stable plasma drug levels and potentially improving adherence. Traditional fluoxetine requires daily intake, which can lead to compliance issues.

2. What are the main advantages of a long-acting fluoxetine formulation?
Key benefits include improved patient adherence, reduced dosing frequency, minimized peak-related side effects, and potential stabilization of mood symptoms over time.

3. When is Prozac Weekly expected to receive regulatory approval?
As of early 2023, regulatory submission has been completed, with approval anticipated within 12 months, contingent on review outcomes.

4. What patient populations are most likely to benefit from Prozac Weekly?
Patients with a history of non-adherence, those on complex medication regimens, and individuals with moderate to severe depression or anxiety are primary candidates.

5. What are the main challenges facing Prozac Weekly's market entry?
Potential challenges include regulatory delays, competition from generic formulations or alternative long-acting therapies, cost concerns, and prescriber hesitancy to adopt new formulations.

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Sources

[1] Global antidepressant market analysis, 2022.
[2] Adherence patterns in antidepressant therapy, Journal of Psychiatry, 2021.