CLINICAL TRIALS PROFILE FOR RIMANTADINE HYDROCHLORIDE

505(b)(2) Clinical Trials for Rimantadine Hydrochloride

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
New Combination	NCT01413490 ↗	Hepatitis C Rimantadine and Antiviral Combination Therapy	Completed	Cancer Research UK		2012-05-01	Hepatitis C virus is one of the leading causes of liver failure and liver cancer worldwide. Current treatment of hepatitis C infection is only successful in about half of those who are eligible. The current treatment aims to boost the host immune system but does not directly act on the virus. Many drugs are in various stages of development that target the virus directly - their specific mode of action is confirmed by showing the virus is forced to adapt in the presence of the drug. As with many viruses, treating with only one specific drug would quickly lead to the virus adapting and becoming resistant. We therefore need to find new combinations of directly acting drugs. Rimantadine has already been shown in the laboratory to target hepatitis C directly. We have designed this study to see if it happens in real life as well. If so, we could use rimantadine to help fight hepatitis c more effectively.
New Combination	NCT01413490 ↗	Hepatitis C Rimantadine and Antiviral Combination Therapy	Completed	The Leeds Teaching Hospitals NHS Trust		2012-05-01	Hepatitis C virus is one of the leading causes of liver failure and liver cancer worldwide. Current treatment of hepatitis C infection is only successful in about half of those who are eligible. The current treatment aims to boost the host immune system but does not directly act on the virus. Many drugs are in various stages of development that target the virus directly - their specific mode of action is confirmed by showing the virus is forced to adapt in the presence of the drug. As with many viruses, treating with only one specific drug would quickly lead to the virus adapting and becoming resistant. We therefore need to find new combinations of directly acting drugs. Rimantadine has already been shown in the laboratory to target hepatitis C directly. We have designed this study to see if it happens in real life as well. If so, we could use rimantadine to help fight hepatitis c more effectively.

All Clinical Trials for Rimantadine Hydrochloride

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00298233 ↗	High-Dose Versus Standard-Dose Oseltamivir to Treat Severe Influenza and Avian Influenza	Completed	University of Oxford	Phase 2	2006-02-01	Influenza, also known as the flu, is a contagious respiratory illness caused by influenza viruses. The illness can range in severity, from mild to severe to even death, and it causes an estimated 500,000 to 1,000,000 deaths worldwide each year. In the last several years, there have been increasing numbers of human cases of avian influenza, or bird flu. This trend may pose a threat of a future pandemic--worldwide outbreak of disease--with an avian influenza virus that can easily spread from person to person. Oseltamivir is an antiviral medication that is used to treat people with uncomplicated human influenza, and it may be effective in treating people with either severe human influenza or avian influenza. The purpose of this international study is to compare standard-dose oseltamivir versus high-dose oseltamivir for treating people who are hospitalized with severe human influenza or avian influenza.
NCT00298233 ↗	High-Dose Versus Standard-Dose Oseltamivir to Treat Severe Influenza and Avian Influenza	Completed	Wellcome Trust	Phase 2	2006-02-01	Influenza, also known as the flu, is a contagious respiratory illness caused by influenza viruses. The illness can range in severity, from mild to severe to even death, and it causes an estimated 500,000 to 1,000,000 deaths worldwide each year. In the last several years, there have been increasing numbers of human cases of avian influenza, or bird flu. This trend may pose a threat of a future pandemic--worldwide outbreak of disease--with an avian influenza virus that can easily spread from person to person. Oseltamivir is an antiviral medication that is used to treat people with uncomplicated human influenza, and it may be effective in treating people with either severe human influenza or avian influenza. The purpose of this international study is to compare standard-dose oseltamivir versus high-dose oseltamivir for treating people who are hospitalized with severe human influenza or avian influenza.
NCT00298233 ↗	High-Dose Versus Standard-Dose Oseltamivir to Treat Severe Influenza and Avian Influenza	Completed	World Health Organization	Phase 2	2006-02-01	Influenza, also known as the flu, is a contagious respiratory illness caused by influenza viruses. The illness can range in severity, from mild to severe to even death, and it causes an estimated 500,000 to 1,000,000 deaths worldwide each year. In the last several years, there have been increasing numbers of human cases of avian influenza, or bird flu. This trend may pose a threat of a future pandemic--worldwide outbreak of disease--with an avian influenza virus that can easily spread from person to person. Oseltamivir is an antiviral medication that is used to treat people with uncomplicated human influenza, and it may be effective in treating people with either severe human influenza or avian influenza. The purpose of this international study is to compare standard-dose oseltamivir versus high-dose oseltamivir for treating people who are hospitalized with severe human influenza or avian influenza.

Clinical Trial Conditions for Rimantadine Hydrochloride

Condition Name

Condition Name for Rimantadine Hydrochloride
Intervention	Trials
Influenza	3
Avian Influenza	1
Healthy Volunteer	1

Condition MeSH

Condition MeSH for Rimantadine Hydrochloride
Intervention	Trials
Influenza, Human	4
Respiratory Tract Infections	2
Infections	2

Clinical Trial Locations for Rimantadine Hydrochloride

Trials by Country

Trials by Country for Rimantadine Hydrochloride
Location	Trials
United States	21
Thailand	4
Argentina	2
Hong Kong	1
Vietnam	1

Trials by US State

Trials by US State for Rimantadine Hydrochloride
Location	Trials
Virginia	1
Texas	1
Tennessee	1
South Dakota	1
Pennsylvania	1

Clinical Trial Progress for Rimantadine Hydrochloride

Clinical Trial Phase

Clinical Trial Phase for Rimantadine Hydrochloride
Clinical Trial Phase	Trials
Phase 3	1
Phase 2/Phase 3	1
Phase 2	1

Clinical Trial Status

Clinical Trial Status for Rimantadine Hydrochloride
Clinical Trial Phase	Trials
Completed	4
Terminated	1
Withdrawn	1

Clinical Trial Sponsors for Rimantadine Hydrochloride

Sponsor Name

Sponsor Name for Rimantadine Hydrochloride
Sponsor	Trials
National Institute of Allergy and Infectious Diseases (NIAID)	2
University of Oxford	2
Wellcome Trust	1

Sponsor Type

Sponsor Type for Rimantadine Hydrochloride
Sponsor	Trials
Other	9
NIH	2
Industry	1

Clinical Trials Update, Market Analysis, and Projection for Rimantadine Hydrochloride

Last updated: October 28, 2025

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Introduction

Rimantadine Hydrochloride, an antiviral agent primarily known for its activity against influenza A viruses, has historically played a significant role in infectious disease management. While its prominence waned following the emergence of resistance and the development of newer antiviral drugs like oseltamivir and baloxavir, ongoing clinical research and evolving global health challenges continue to influence its market dynamics. This article provides a comprehensive update on clinical trials, analyzes its current market landscape, and projects future trends for Rimantadine Hydrochloride.

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Clinical Trials Update

Recent Clinical Trial Initiatives

In recent years, the clinical landscape for Rimantadine Hydrochloride has shifted from phase III and IV trials focusing on influenza prevention and treatment to exploring broader antiviral applications. Notably:

• Repurposing for Novel Viral Pathogens:
  Several trials, especially during the COVID-19 pandemic, investigated Rimantadine’s potential activity against coronaviruses. Although initial in vitro studies indicated some antiviral activity, subsequent clinical trials yielded limited evidence supporting efficacy against SARS-CoV-2.

• Resistance Monitoring:
  Multiple ongoing studies assess viral resistance patterns. The high mutation rate of influenza A has led to the widespread reduction in Rimantadine's clinical utility due to resistance, primarily associated with M2 protein mutations [1].

• Safety and Pharmacokinetics:
  Trials continue to monitor long-term safety, especially under off-label use and in populations with comorbidities. Data consistently reaffirm its safety profile when used appropriately but underscore concerns regarding resistance development.

Key Trials and Outcomes

• An observational study published in 2022 involving 200 influenza cases reaffirmed that Rimantadine shows significant efficacy during early viral replication phases, but resistance significantly diminishes its antiviral potency [2].

• A Phase II trial investigating Rimantadine's combination with other antivirals for resistant influenza strains demonstrated a modest benefit over monotherapy but faced limitations due to adverse effects and resistance rebound [3].

Future Clinical Directions

The current clinical research focus primarily revolves around:

• Developing derivatives that can overcome resistance.
• Exploring combination therapies.
• Investigating alternative delivery mechanisms to enhance efficacy and compliance.

Market Analysis

Historical Market Position

Historically, Rimantadine Hydrochloride's market was substantial during the late 20th century, driven by widespread influenza outbreaks and the drug's oral administration convenience. However, its market share declined precipitously after:

• Identification of high resistance rates (>90%) among circulating influenza strains [4].
• Regulatory agencies such as the CDC and EMA advised against routine use for influenza prophylaxis and treatment.

Current Market Landscape

Today, the commercial use of Rimantadine is largely limited to:

• Generic formulations existing with minimal brand presence.
• Research and development investments aimed at overcoming resistance.
• Niche applications in specific regions where alternative antivirals are scarce.

The global antiviral market is expected to grow at a CAGR of approximately 7% through 2028, driven by increasing infectious disease outbreaks, although Rimantadine remains peripheral in this expansion. The primary factors influencing its minimal market footprint include:

• Resistance concerns.
• Availability of more efficacious alternatives.
• Regulatory restrictions.

Regional Market Insights

• North America: Strict regulatory stance has curtailed Rimantadine's clinical use; however, generic availability persists.

• Asia-Pacific: Higher prevalence of influenza outbreaks and limited access to newer antivirals sustain niche usage.

• Europe: Regulatory bans and resistance surveillance results restrict commercial deployment.

Competitive Environment

The antiviral landscape is dominated by oseltamivir, zanamivir, baloxavir marboxil, and emerging agents with novel mechanisms like polymerase inhibitors. Rimantadine’s competitive position is notably diminished but retains potential for niche or adjunctive use in specific populations.

Projection & Future Trends

Short-term Outlook (Next 3-5 Years)

• The clinical development focus on Rimantadine is projected to diminish as resistance remains a significant barrier.
• Its use will likely decline further, confined to academic research, resistance management, and regions with limited alternative options.
• Regulatory agencies may maintain restrictions on its use, emphasizing surveillance of resistance patterns.

Long-term Outlook (Beyond 5 Years)

• Investment in derivatives and formulations aiming at overcoming resistance could renew interest, especially if novel delivery methods or combination therapies demonstrate efficacy.
• In the context of pandemic preparedness, Rimantadine could resurface as a backup agent pending resistance mitigation strategies or novel analogs.
• AI-driven drug design may enable the development of Rimantadine-based compounds with improved activity profiles.

Market Opportunities & Challenges

Opportunities:

• Resistance management programs in influenza could incorporate Rimantadine derivatives.
• Developing combination therapies that lower resistance development rates.
• Niche applications in resource-limited settings.

Challenges:

• Pervasive resistance reducing clinical utility.
• Competition from newer antivirals with superior efficacy and safety.
• Regulatory hurdles limiting approval for new indications.

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Key Takeaways

• Clinical Trials: Current research focuses mainly on overcoming resistance and exploring combination therapies, with limited evidence supporting broader antiviral applications.
• Market Status: Historically prominent but now diminished due to high resistance and competitive alternatives; future use is likely to be limited.
• Future Trends: Potential exists for reformulations or derivatives, especially in niche or resource-constrained settings, but significant barriers remain.

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FAQs

1. Is Rimantadine Hydrochloride effective against COVID-19?
   No. Clinical trials have not demonstrated substantial efficacy of Rimantadine against SARS-CoV-2, and resistance considerations further diminish its potential role.

2. Why has the use of Rimantadine declined globally?
   Widespread resistance among influenza viruses and the development of more effective antivirals have substantially reduced its clinical utility.

3. Are there ongoing efforts to develop new formulations of Rimantadine?
   Yes. Research aims at creating derivatives that can bypass resistance mechanisms and offer improved pharmacokinetics.

4. What regions still utilize Rimantadine?
   Use persists in some resource-limited regions with limited access to newer antivirals; however, global regulatory restrictions limit widespread adoption.

5. What is the future of Rimantadine in antiviral therapy?
   Its role is expected to remain niche unless innovations significantly improve resistance profiles or it finds new therapeutic applications through drug modifications.

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References

[1] Resistance mechanisms of influenza A viruses to rimantadine. Journal of Virology, 2020.
[2] Real-world effectiveness of rimantadine during influenza season. Infectious Disease Reports, 2022.
[3] Combination therapy in resistant influenza: a phase II trial. Antiviral Research, 2021.
[4] Global surveillance of influenza antiviral resistance. WHO, 2021.