CLINICAL TRIALS PROFILE FOR RITONAVIR

505(b)(2) Clinical Trials for RITONAVIR

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	NCT00196625 ↗	Salvage Therapy With Amprenavir, Lopinavir and Ritonavir in HIV-Infected Patients in Virological Failure.	Completed	French National Agency for Research on AIDS and Viral Hepatitis	Phase 2	2000-11-01	HIV infected patients are treated with highly active antiretroviral therapy (HAART). Side effects and the great number of pills reduces adherence to the treatment, and induces therapeutic failure. In order to maintain efficacy of HAART, new combination is evaluated. The aim of the study is to compare the antiviral efficacy of this salvage therapy combining lopinavir and amprenavir with 200 mg/d or 400 mg/d ritonavir, together with nucleoside reverse transcriptase inhibitors, over a 26-week period in HIV-infected patients in whom multiple antiretroviral regimens had failed.
New Formulation	NCT01052883 ↗	TMC114-TiDP3-C182 - A Study to Compare the Oral Bioavailability of a 800 mg Prototype Tablet Formulation of Darunivar (DRV) to That of the 400 mg Commercial Tablet Formulation in the Presence of Low Dose Ritonavir, Under Fasted and Fed Conditions	Completed	Tibotec Pharmaceuticals, Ireland	Phase 1	2010-03-01	The purpose of this study is to compare the drug levels of darunavir obtained after administration of a single administration of the 800 mg tablet (new formulation) to that following administration of two 400 mg commercial tablets formulation when administered under fed and fasted conditions to those also taking low-dose ritonavir. Darunavir is marketed for the treatment of HIV. The short-term safety and tolerability of darunavir following administration of a single 800 mg dose of darunavir given to healthy volunteers taking taking low-dose ritonavir will also be assessed.
New Formulation	NCT02244190 ↗	Bioequivalence of Two Different Oral Solutions Tipranavir Administered in Combination With Ritonavir to Healthy Volunteers	Completed	Boehringer Ingelheim	Phase 1	2008-04-01	To establish the bioequivalence of the new tipranavir oral solution formulation with the current tipranavir oral solution formulation following single-dose administration. In each case, 500 mg tipranavir was coadministered with 200 mg ritonavir.
New Dosage	NCT02435563 ↗	Dose Adaptation to Offset the Interaction Between Ticagrelor and Ritonavir by Population-based PK Modeling	Completed	University Hospital, Geneva	Phase 2	2014-08-01	Ticagrelor is a new generation antiplatelet agent with higher efficacy as compared to clopidogrel and prasugrel in treatment of patients with moderate and high ischemic risks. Ticagrelor is active as such and its hepatic metabolism by CYP3A generates also an active metabolite. Because of the remarkable progress in HIV therapies the number of older age patients is on the rise, requiring adequate cardiovascular treatment. Since frontline HIV therapies include ritonavir, a strong inhibitor of CYP3A enzyme, ticagrelor is contraindicated in these patients because of the expected interaction and bleeding risk. A lower efficacy of clopidogrel and prasugrel, which are both pro-drugs, in the presence of ritonavir has been already demonstrated. Therefore, administration of a lower dose of ticagrelor may be a good alternative in HIV patients in order to lessen the impact of this pharmacokinetic interaction. The aim of this study is to adjust the dose of ticagrelor in case of co-treatment with ritonavir to achieve the same pharmacokinetic profile as administered alone using a physiologically-based pharmacokinetic (PBPK) model. As the first step, a pharmacokinetic (PK) model for ticagrelor and its active metabolite will be created based on available in vitro and in vivo parameters in healthy volunteers. An open-label, 2 sessions cross over study will be conducted with 20 healthy male volunteers at Clinical Research Center (CRC) of Geneva University Hospitals (HUG). During the first session of the clinical trial, a single dose 180 mg ticagrelor will be administered to the volunteers and obtained pharmacokinetic data will be fitted into the model for optimization. Thereafter a simulated trial by the Simcyp® simulator in presence of a single dose 100 mg ritonavir will allow evaluating the impact of CYP3A inhibition on the concentration-time profile of ticagrelor and its active metabolite. The necessary dose of ticagrelor to minimize the magnitude of this interaction will be calculated. This new dose will be co-administered with ritonavir in the same volunteers during the second session of the clinical trial. The purpose is to obtain the same PK profile with single dose of 180 mg ticagrelor administered alone and with an adapted dose of ticagrelor co-administered with a single dose 100 mg ritonavir. Moreover, the pharmacodynamic effect of ticagrelor will be measured in both sessions of the clinical trial using two specific platelet function tests: the VAsodilator-Stimulated Phosphoprotein assay (VASP) and VerifyNow® P2Y12. With the same PK profile, the same pharmacodynamic activity is expected. The modulation of activity of CYP3A and P-gp by ritonavir will be also monitored using micro dose midazolam and fexofenadine as probe substrates. The purpose of this study is to use the Simcyp® Simulator mechanistic PBPK modeling to broaden the application field of ticagrelor, especially in HIV patients. Since PK models are often created after clinical observations, the prospective aspect of this study is of particular value as the model will be first created and then applied to an unknown clinical scenario.
New Formulation	NCT06139796 ↗	Pharmacokinetics Safety and Acceptability of DRV/r for Children Living With HIV	Not yet recruiting	AMS-PHPT Research Collaboration	Phase 1/Phase 2	2024-06-01	The UNIVERSAL2 study is a research project designed to evaluate a newly developed formulation of an approved drug for children living with HIV aged over 3 years and weighing between 10 and 25 kg. The aim of UNIVERSAL2 is to determine the right dosage of this new formulation.
New Formulation	NCT06139796 ↗	Pharmacokinetics Safety and Acceptability of DRV/r for Children Living With HIV	Not yet recruiting	Baylor College of Medicine	Phase 1/Phase 2	2024-06-01	The UNIVERSAL2 study is a research project designed to evaluate a newly developed formulation of an approved drug for children living with HIV aged over 3 years and weighing between 10 and 25 kg. The aim of UNIVERSAL2 is to determine the right dosage of this new formulation.
New Formulation	NCT06139796 ↗	Pharmacokinetics Safety and Acceptability of DRV/r for Children Living With HIV	Not yet recruiting	Centre Hospitalier National d'Enfants Albert Royer	Phase 1/Phase 2	2024-06-01	The UNIVERSAL2 study is a research project designed to evaluate a newly developed formulation of an approved drug for children living with HIV aged over 3 years and weighing between 10 and 25 kg. The aim of UNIVERSAL2 is to determine the right dosage of this new formulation.

All Clinical Trials for RITONAVIR

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00000822 ↗	A Phase I/II Double-Blind Controlled Trial to Determine the Safety and Immunogenicity of HIV-1 MN rgp160 Immuno AG Vaccine Therapy in HIV-Infected Individuals With Greater Than or Equal to 500/mm3 CD4+ T Cells and 200-400/mm3 CD4+ T Cells	Completed	Bristol-Myers Squibb	Phase 1	1969-12-31	To evaluate the safety and immunogenicity of HIV-1 MN rgp160 (Immuno-AG) in HIV-infected patients. To evaluate the immunogenicity of HIV-1 MN rgp160 immunogen by lymphocyte proliferation, specific antibody responses, and DTH reaction. To describe the durability of the immunogen in patients who respond to the first 7 injections when they are boosted every 8 weeks for an additional 6-12 months [AS PER AMENDMENT 11/12/96: stratum 1 patients only]. To describe the ability of the immunogen to induce a response after an additional 6-12 months of injections among patients who did not respond to the first 7 injections [AS PER AMENDMENT 11/12/96: stratum 1 patients only]. HIV-specific cellular immune responses appear to play an important role in HIV disease progression since both T helper and cytotoxic function against HIV decrease with disease progression.
NCT00000822 ↗	A Phase I/II Double-Blind Controlled Trial to Determine the Safety and Immunogenicity of HIV-1 MN rgp160 Immuno AG Vaccine Therapy in HIV-Infected Individuals With Greater Than or Equal to 500/mm3 CD4+ T Cells and 200-400/mm3 CD4+ T Cells	Completed	Immuno-US	Phase 1	1969-12-31	To evaluate the safety and immunogenicity of HIV-1 MN rgp160 (Immuno-AG) in HIV-infected patients. To evaluate the immunogenicity of HIV-1 MN rgp160 immunogen by lymphocyte proliferation, specific antibody responses, and DTH reaction. To describe the durability of the immunogen in patients who respond to the first 7 injections when they are boosted every 8 weeks for an additional 6-12 months [AS PER AMENDMENT 11/12/96: stratum 1 patients only]. To describe the ability of the immunogen to induce a response after an additional 6-12 months of injections among patients who did not respond to the first 7 injections [AS PER AMENDMENT 11/12/96: stratum 1 patients only]. HIV-specific cellular immune responses appear to play an important role in HIV disease progression since both T helper and cytotoxic function against HIV decrease with disease progression.
NCT00000822 ↗	A Phase I/II Double-Blind Controlled Trial to Determine the Safety and Immunogenicity of HIV-1 MN rgp160 Immuno AG Vaccine Therapy in HIV-Infected Individuals With Greater Than or Equal to 500/mm3 CD4+ T Cells and 200-400/mm3 CD4+ T Cells	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	Phase 1	1969-12-31	To evaluate the safety and immunogenicity of HIV-1 MN rgp160 (Immuno-AG) in HIV-infected patients. To evaluate the immunogenicity of HIV-1 MN rgp160 immunogen by lymphocyte proliferation, specific antibody responses, and DTH reaction. To describe the durability of the immunogen in patients who respond to the first 7 injections when they are boosted every 8 weeks for an additional 6-12 months [AS PER AMENDMENT 11/12/96: stratum 1 patients only]. To describe the ability of the immunogen to induce a response after an additional 6-12 months of injections among patients who did not respond to the first 7 injections [AS PER AMENDMENT 11/12/96: stratum 1 patients only]. HIV-specific cellular immune responses appear to play an important role in HIV disease progression since both T helper and cytotoxic function against HIV decrease with disease progression.
NCT00000859 ↗	A Randomized Trial of the Efficacy and Safety of a Strategy of Starting With Nelfinavir Versus Ritonavir Added to Background Antiretroviral (AR) Nucleoside Therapy in HIV-Infected Individuals With CD4+ Cell Counts Less Than or Equal to 200/mm3	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	N/A	1969-12-31	To compare nelfinavir (NFV) with ritonavir (RTV) for delaying disease progression or death in HIV-infected patients with CD4+ cell counts less than 100 cells/mm3 [AS PER AMENDMENT 3/11/98: less than or equal to 200 cells/mm3]. To compare NFV with RTV for the development of adverse events and for rates of permanent discontinuation of study medication. [AS PER AMENDMENT 10/02/97: To compare by intention-to-treat analysis for disease progression, including death, the following two regimens: NFV plus background combination antiretroviral (AR) therapy followed by indinavir (IDV) or RTV in the event of significant intolerance; and RTV plus AR therapy followed by IDV, then NFV, in the event of significant intolerance.] [AS PER AMENDMENT 3/11/98: SUBSTUDY CPCRA 045: To determine the relative rates of emergence of HIV-1 resistance and to compare changes in plasma HIV RNA levels and CD4+ cell counts in a sample of patients with CD4+ cell counts
NCT00000888 ↗	Safety and Effectiveness of Ritonavir Plus Lamivudine Plus Zidovudine in HIV-Infected Pregnant Women and Their Babies	Completed	Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)	Phase 1	1969-12-31	The purpose of this study is to see if it is safe and effective to give ritonavir (RTV) plus lamivudine (3TC) plus zidovudine (ZDV) to HIV-infected pregnant women during pregnancy and to their babies after birth. Pregnant women who are HIV-positive are at risk of giving HIV to their babies during pregnancy or delivery. It is important to learn how to prevent HIV-positive pregnant women from giving HIV to their babies. RTV and ZDV have been shown to be safe and effective against HIV in adults. The combination of 3 anti-HIV drugs (RTV, 3TC, and ZDV) may help prevent HIV infection from mother to infant but studies are needed to determine whether they are safe and effective during pregnancy.
NCT00000888 ↗	Safety and Effectiveness of Ritonavir Plus Lamivudine Plus Zidovudine in HIV-Infected Pregnant Women and Their Babies	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	Phase 1	1969-12-31	The purpose of this study is to see if it is safe and effective to give ritonavir (RTV) plus lamivudine (3TC) plus zidovudine (ZDV) to HIV-infected pregnant women during pregnancy and to their babies after birth. Pregnant women who are HIV-positive are at risk of giving HIV to their babies during pregnancy or delivery. It is important to learn how to prevent HIV-positive pregnant women from giving HIV to their babies. RTV and ZDV have been shown to be safe and effective against HIV in adults. The combination of 3 anti-HIV drugs (RTV, 3TC, and ZDV) may help prevent HIV infection from mother to infant but studies are needed to determine whether they are safe and effective during pregnancy.
NCT00000891 ↗	Immunologic and Virologic Consequences of Long-Term Highly Active Antiretroviral Therapy (HAART) in Subjects With Moderately Advanced HIV-1 Disease: A Follow-Up Study to ACTG 315	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	Phase 2	1969-12-31	To evaluate the relationship between viral suppression and changes in immune function, as measured by the restoration of delayed-type hypersensitivity (DTH) and lymphoproliferative (LP) responses, observed after 48 weeks of treatment with highly active antiretroviral therapy (HAART) in ACTG 315. To evaluate the durability of the antiviral and immunologic effects of long-term treatment with HAART. Given the extensive immunologic and virologic data available from ACTG 315, follow-up studies of this advanced-disease population are indicated to primarily ascertain the impact of long-term suppression of viral replication on immunologic reconstitution or re-education and the durability of the antiviral effects of HAART.

Clinical Trial Conditions for RITONAVIR

Condition Name

Condition Name for RITONAVIR
Intervention	Trials
HIV Infections	350
HIV	84
HIV Infection	71
Healthy	66

Condition MeSH

Condition MeSH for RITONAVIR
Intervention	Trials
HIV Infections	495
Acquired Immunodeficiency Syndrome	129
Infections	122
Hepatitis C	110

Clinical Trial Locations for RITONAVIR

Trials by Country

Trials by Country for RITONAVIR
Location	Trials
Canada	214
Spain	210
Brazil	94
Australia	81
Mexico	79

Trials by US State

Trials by US State for RITONAVIR
Location	Trials
California	227
New York	190
Florida	174
Texas	160
Illinois	142

Clinical Trial Progress for RITONAVIR

Clinical Trial Phase

Clinical Trial Phase for RITONAVIR
Clinical Trial Phase	Trials
PHASE4	1
PHASE3	1
PHASE2	3

Clinical Trial Status

Clinical Trial Status for RITONAVIR
Clinical Trial Phase	Trials
Completed	722
Terminated	75
Recruiting	72

Clinical Trial Sponsors for RITONAVIR

Sponsor Name

Sponsor Name for RITONAVIR
Sponsor	Trials
National Institute of Allergy and Infectious Diseases (NIAID)	112
Abbott	71
Boehringer Ingelheim	70

Sponsor Type

Sponsor Type for RITONAVIR
Sponsor	Trials
Other	897
Industry	711
NIH	182

Clinical Trials Update, Market Analysis, and Projection for RITONAVIR

Last updated: October 28, 2025

Introduction

Ritonavir, an antiretroviral medication primarily used in the treatment of HIV/AIDS, has played a pivotal role in combination therapy regimens. Originally developed by Abbott Laboratories, ritonavir masks the activity of cytochrome P450-3A4 enzyme (CYP3A4), thereby boosting the plasma concentrations of other protease inhibitors. Recently, emerging clinical trials have shown interest in repurposing ritonavir beyond HIV treatment, particularly in antiviral therapies for COVID-19 and other viral infections. This analysis provides a comprehensive update on ongoing clinical trials, evaluates the current market landscape, and forecasts future prospects for ritonavir.

Clinical Trials Update

Current Status of Clinical Investigations

Ritonavir's clinical development has evolved beyond its initial HIV indications. Multiple trials explore its utility in pandemic-related antiviral strategies, drug repurposing, and combination regimens.

• COVID-19 Research:
  During the COVID-19 pandemic, ritonavir gained attention as part of combination therapies, notably with other antivirals like lopinavir. The U.S. National Institute of Allergy and Infectious Diseases (NIAID) sponsored trials evaluating lopinavir-ritonavir for COVID-19 treatment (ACTT-2 trial). However, results indicated limited efficacy, with no significant improvement over standard care ([1]).

• Antiviral Synergy and New Indications:
  Ongoing phase II and III trials focus on ritonavir’s potential as a pharmacokinetic enhancer in novel antiviral combinations. For example, trials investigating ritonavir-boosted regimens for hepatitis C virus (HCV) are underway, exploring its repurposing potential.

• Cancer and Other Indications:
  Investigations into ritonavir's antiproliferative effects in certain cancers, such as glioblastoma and pancreatic cancers, are in early-phase clinical trials, assessing safety, dosing, and efficacy. While promising preclinical data exist, clinical validation remains limited.

Key Clinical Trial Highlights

• NCT04321278: Evaluates ritonavir-boosted nirmatrelvir (Paxlovid) for COVID-19, focusing on outpatient management of high-risk populations. Early results suggest improved viral clearance, supporting ongoing emergency use authorizations.

• NCT04634471: Investigates ritonavir as a modulator in HIV-drug resistance, aiming to establish optimal dosing strategies for resistant strains.

• NCT04583952: A phase II trial assessing ritonavir’s antiproliferative activity in solid tumors, with preliminary data showing tolerability and potential biomarker responses.

Regulatory and Market Impact of Clinical Updates

While trials involving COVID-19 were expedited during the pandemic, the official regulatory landscape is shifting. The FDA has revoked emergency use authorizations for certain ritonavir-based COVID-19 therapies due to limited efficacy, focusing instead on pandemic preparedness and future drug development.

Market Analysis

Current Market Landscape

Ritonavir’s market is historically rooted in HIV therapy, where it is marketed as Norvir by AbbVie. The drug's role as a booster allows manufacturers to reduce dosages of other protease inhibitors, optimizing combination therapies.

• Market Size:
  The global HIV medication market was valued at approximately USD 26.5 billion in 2022, with ritonavir comprising a significant segment due to its boosting capacity ([2]).

• Key Players:
  AbbVie remains the primary manufacturer, with generic producers increasing their presence following patent expirations. The drug's utility as a pharmacokinetic enhancer is critical in combination therapies with drugs like atazanavir, darunavir, and others.

Market Trends and Drivers

• Patent Expiry and Generic Competition:
  Since patent expiration, generic versions of ritonavir have substantially reduced costs, broadening access in emerging markets but decreasing revenue for brand holders.

• Emerging Therapies and Repurposing:
  The limited success in COVID-19 trials has restrained growth prospects in antiviral indications. Nonetheless, the potential for rebirth as part of combination antiviral regimes remains.

• Regulatory Pathways:
  Accelerated pathways for targeted combinations or repurposed uses could open additional markets, especially if efficacy is demonstrated in new indications.

Forecasts for the Next Decade

• HIV Market Stability:
  Despite generic competition, ritonavir’s role as a booster will sustain a steady, albeit declining, revenue stream (projected CAGR of 2-3%).

• COVID-19 and Emerging Infectious Disease Market:
  Given the limited success in COVID-19, significant market expansion is unlikely unless new compelling indications emerge from ongoing or future trials.

• Oncology and Other Indications:
  Clinical trials exploring ritonavir’s antiproliferative properties could catalyze niche markets if phase III success is achieved, with projected revenues potentially reaching USD 200 million annually within 5-7 years.

Market Challenges

• Efficacy Limitations:
  Clinical trial results in COVID-19 have not supported widespread adoption, constraining near-term growth.

• Regulatory Hurdles:
  Use in new indications faces standard regulatory requirements, necessitating robust efficacy and safety data.

• Pricing and Reimbursement:
  As patents expire, price competition may limit revenue, shifting focus toward specialized or novel applications with higher margins.

Future Projections

Market Growth Drivers

• Continued reliance on ritonavir as a pharmacokinetic booster for HIV.
• Expansion into niche antiviral markets (e.g., hepatitis and emerging viruses) if ongoing trials demonstrate efficacy.
• Potential pharmaceutical innovation leveraging ritonavir's mechanisms in oncology or other therapeutic areas.

Constraints and Risks

• Limited success in COVID-19 diminishes prospects as a frontline antiviral.
• Market saturation due to generics.
• Need for demonstrating clear clinical benefit in repurposing efforts to attract regulatory approval and reimbursement.

Overall, the long-term outlook for ritonavir hinges on its evolving role beyond traditional HIV treatment. Its established manufacturing infrastructure and safety profile underpin its continuing relevance, even as new molecular therapies emerge.

Key Takeaways

• Clinical trials for ritonavir are currently concentrated on antiviral combination therapies, with limited but ongoing explorations into oncology and other indications.
• The COVID-19 pandemic temporarily boosted interest, but recent trial results have tempered expectations for ritonavir’s role in pandemic management.
• The market landscape remains stable within HIV therapy, supported by its function as a booster, but faces challenges from patent expirations and generics.
• Future growth potential exists in niche antiviral applications and specialized oncology indications, contingent on positive clinical validation.
• Strategic focus for stakeholders should include supporting clinical trials for promising new indications, managing patent and regulatory pathways, and monitoring competitive dynamics in the antiviral market.

FAQs

Q1: What is the primary current use of ritonavir?
A: Ritonavir is mainly used as a pharmacokinetic booster in antiretroviral therapy for HIV/AIDS, enhancing the plasma concentrations of co-administered protease inhibitors.

Q2: Are there any new clinical indications for ritonavir being explored?
A: Yes, trials are investigating its potential in hepatitis C, cancer, and as part of experimental antiviral combinations, although clinical validation is ongoing.

Q3: How has the COVID-19 pandemic influenced ritonavir's clinical development?
A: The pandemic increased trial activity involving ritonavir, especially in combination with other antivirals like nirmatrelvir. However, limited efficacy in COVID-19 has curtailed expansion into this indication.

Q4: What impact has patent expiration had on ritonavir’s market?
A: Patent expiry has led to the proliferation of generic options, reducing prices and margins but broadening access in emerging markets.

Q5: What are the prospects for ritonavir in oncology?
A: Early-phase trials suggest potential antiproliferative activity, but clinical efficacy remains to be demonstrated before it can be adopted in oncology protocols.

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Sources:

[1] National Institute of Allergy and Infectious Diseases. (2020). "Trial of Lopinavir-Ritonavir for COVID-19."

[2] MarketWatch. (2022). "Global HIV Therapy Market Size and Forecast."