CLINICAL TRIALS PROFILE FOR TELAPREVIR

505(b)(2) Clinical Trials for telaprevir

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 Formulation	NCT01511432 ↗	A Study to Assess the Relative Bioavailability Three New Formulations of Telaprevir in Healthy Subjects	Completed	Vertex Pharmaceuticals Incorporated	Phase 1	2012-01-01	The purpose of this study is to evaluate the relative bioavailability, safety, and tolerability of 3 new formulations of telaprevir relative to the Incivek 375-mg tablets.

All Clinical Trials for telaprevir

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00336479 ↗	Phase 2 Study of VX-950, Pegasys®, and Copegus® in Hepatitis C	Completed	Vertex Pharmaceuticals Incorporated	Phase 2	2006-06-01	Study the effectiveness of telaprevir (VX-950) in combination with Pegylated Interferon Alfa 2a (Peg-IFN-alfa-2a) and Ribavirin (RBV) in reducing plasma hepatitis C virus (HCV) ribonucleic acid (RNA) levels
NCT00372385 ↗	Phase 2 Study of VX-950, Pegasys® With and Without Copegus® in Hepatitis C	Completed	Vertex Pharmaceuticals Incorporated	Phase 2	2006-08-01	Compare the effectiveness of telaprevir (VX-950) in combination with Pegylated Interferon Alfa 2a (Peg-IFN-alfa-2a) with and without Ribavirin (RBV) in reducing plasma hepatitis C virus (HCV) ribonucleic acid (RNA) levels
NCT00420784 ↗	A Study of Telaprevir (VX-950), Pegasys and Copegus in Hepatitis C (PROVE3)	Completed	Vertex Pharmaceuticals Incorporated	Phase 2	2007-02-01	The PROVE3 trial is a partially double blinded, randomized, Phase 2 research study of an investigational drug, Telaprevir (VX-950) or Placebo, with Pegylated Interferon Alfa 2a (Peg-IFN-alfa-2a, Pegasys®), and Ribavirin (RBV, Copegus®) in people with genotype 1 hepatitis C who have not achieved a Sustained Viral Response (SVR) with a previous treatment of interferon therapy.
NCT00509210 ↗	Study of Telaprevir in Subjects With Hepatic Impairment	Completed	Vertex Pharmaceuticals Incorporated	Phase 1	2007-09-01	The purpose of this study is to assess the safety and pharmacokinetics of Telaprevir following administration of multiple oral doses to subjects with moderate and severe hepatic impairment.
NCT00528528 ↗	An Open-Label Study of Telaprevir Administered Every 12 or 8 Hours in Combination With One of Two Pegylated Interferons and Ribavirin in Treatment-Naive Genotype 1 Chronic Hepatitis C Participants	Completed	Tibotec BVBA	Phase 2	2007-10-01	The purpose of this study is to explore the efficacy, safety, tolerability, pharmacokinetics (the study of the way a drug enters and leaves the blood and tissues over time), and pharmacokinetic-pharmacodynamic relationships of telaprevir administered in two different doses in combination with two standard therapies commercially available for chronic (lasting a long time) genotype 1 Hepatitis (inflammation of the liver) C virus (HCV) infection.
NCT00535847 ↗	A Rollover Study for Subjects Participating in the Control Arm of Study VX06-950-106, VX05-950-104 and VX05-950-104EU Whose Plasma Hepatitis C Virus (HCV) Ribonucleic Acid (RNA) Levels Did Not Respond to Therapy	Completed	Tibotec, Inc	Phase 2	2007-10-01	To provide access to a telaprevir-based treatment to subjects of the Control Group of Study VX06-950-106 (NCT00420784), VX05-950-104 (NCT00336479), and VX05-950-104EU (NCT00372385) who stopped treatment due to inadequate response to treatment. Safety, tolerability, and Hepatitis C Virus (HCV) Ribonucleic Acid (RNA) levels will be collected.
NCT00535847 ↗	A Rollover Study for Subjects Participating in the Control Arm of Study VX06-950-106, VX05-950-104 and VX05-950-104EU Whose Plasma Hepatitis C Virus (HCV) Ribonucleic Acid (RNA) Levels Did Not Respond to Therapy	Completed	Vertex Pharmaceuticals Incorporated	Phase 2	2007-10-01	To provide access to a telaprevir-based treatment to subjects of the Control Group of Study VX06-950-106 (NCT00420784), VX05-950-104 (NCT00336479), and VX05-950-104EU (NCT00372385) who stopped treatment due to inadequate response to treatment. Safety, tolerability, and Hepatitis C Virus (HCV) Ribonucleic Acid (RNA) levels will be collected.

Clinical Trial Conditions for telaprevir

Condition Name

Condition Name for telaprevir
Intervention	Trials
Hepatitis C	46
Hepatitis C, Chronic	16
Chronic Hepatitis C	10
HIV	7

Condition MeSH

Condition MeSH for telaprevir
Intervention	Trials
Hepatitis C	89
Hepatitis	78
Hepatitis A	58
Hepatitis C, Chronic	43

Clinical Trial Locations for telaprevir

Trials by Country

Trials by Country for telaprevir
Location	Trials
United States	451
Canada	45
Japan	42
Germany	26
United Kingdom	21

Trials by US State

Trials by US State for telaprevir
Location	Trials
Texas	30
New York	26
California	26
Maryland	25
Florida	24

Clinical Trial Progress for telaprevir

Clinical Trial Phase

Clinical Trial Phase for telaprevir
Clinical Trial Phase	Trials
Phase 4	14
Phase 3	25
Phase 2/Phase 3	2

Clinical Trial Status

Clinical Trial Status for telaprevir
Clinical Trial Phase	Trials
Completed	81
Terminated	11
Unknown status	5

Clinical Trial Sponsors for telaprevir

Sponsor Name

Sponsor Name for telaprevir
Sponsor	Trials
Vertex Pharmaceuticals Incorporated	36
Tibotec BVBA	12
Tibotec Pharmaceutical Limited	6

Sponsor Type

Sponsor Type for telaprevir
Sponsor	Trials
Industry	106
Other	94
NIH	7

Clinical Trials Update, Market Analysis, and Projection for Telaprevir

Last updated: October 31, 2025

Introduction

Telaprevir, developed by Vertex Pharmaceuticals, is a next-generation NS3/4A protease inhibitor approved for the treatment of hepatitis C virus (HCV) genotype 1 infection. Approved by the FDA in 2011, telaprevir marked a significant advancement in direct-acting antiviral (DAA) therapy. This report provides a comprehensive update on telaprevir’s clinical trial landscape, current market environment, and future projection, emphasizing its positioning within the hepatitis C treatment paradigm.

Clinical Trials Overview and Updates

Historical Context and Initial Trials

Telaprevir's approval was based on pivotal Phase III trials—namely, the ADVANCE, ILLUMINATE, and REALIZE studies—that demonstrated its efficacy when added to pegylated interferon and ribavirin (PR) therapy. These studies collectively showed considerable improvements in sustained virologic response (SVR) rates compared to PR therapy alone, establishing telaprevir as a cornerstone in HCV management during its initial market introduction.

Recent Clinical Developments

Following regulatory approval, the focus shifted toward optimizing treatment protocols, resisting resistance, and evaluating telaprevir’s role amidst newer therapies. In recent years, several clinical trials have explored alternative formulations, combination regimens, and efficacy in special populations:

• Combination with Sofosbuvir: Trials such as the Phase II study exploring telaprevir combined with sofosbuvir, another potent DAA, indicated synergistic effects with improved SVR rates and shorter treatment durations, potentially replacing older interferon-based regimens.

• Resistance Profile Studies: Ongoing research assesses the resistance barriers posed by telaprevir, particularly mutations in the NS3/4A protease domain that confer decreased susceptibility. These studies inform retreatment strategies and combination therapies.

• Pharmacokinetic and Safety Trials: Recent trials evaluate drug-drug interactions, adverse event profiles, and dosing regimens, especially in populations with comorbidities such as HIV coinfection or cirrhosis.

Discontinuation and Market Withdrawal

Despite its initial success, telaprevir's clinical utility has been constrained by several factors:

• Adverse Effects: High rates of anemia, rash, pruritus, and gastrointestinal symptoms led to treatment discontinuations.
• Drug Resistance and Limited Efficacy: Resistance mutations in certain patient cohorts complicated retreatments.
• Emergence of Second-Generation DAAs: The advent of highly effective, interferon-free regimens such as sofosbuvir/ledipasvir or glecaprevir/pibrentasvir rendered telaprevir obsolete.

Consequently, pharmaceutical companies have largely withdrawn telaprevir from the market, and it is currently available only through compensatory arrangements, private formulary restrictions, or off-label use in some regions.

Market Analysis

Historical Market Position

At its peak in 2012, telaprevir represented approximately $1.2 billion in annual sales globally, primarily driven by the U.S. and European markets. Its rapid adoption was fueled by the urgent need for more effective HCV therapies. Nevertheless, this market share was short-lived owing to the rapid evolution of next-generation DAAs.

Current Market Dynamics

Today, the global hepatitis C treatment market is dominated by interferon-free, pan-genotypic regimens with superior efficacy and tolerability:

• Market Decline: Telaprevir's sales have plummeted, and it is considered a ‘legacy’ agent in the HCV therapeutic landscape.
• Niche and Off-Label Use: Small segments still utilize telaprevir in combination with other DAAs in regions where newer agents are inaccessible due to cost or regulatory constraints.
• Generic and Biosimilar Competition: As patents expire and generics enter emerging markets, prices for newer DAAs will decrease further, amplifying the decline of older agents like telaprevir.

Regulatory and Reimbursement Environment

Most regulatory agencies, including the FDA and EMA, have effectively de-listed telaprevir, limiting reimbursement in many jurisdictions. This policy shift aligns with evolving treatment guidelines that prioritize safer, more effective regimens.

Key Market Drivers and Restraints

Drivers	Restraints
Efficacy in certain genotypes	Adverse safety profile
Combination potential with newer DAAs	Market displacement by second-generation DAAs
Global hepatitis C burden in resource-limited settings	Regulatory withdrawal

Future Market Projection

Given the current landscape, telaprevir's market is expected to continue its downward trajectory. It is unlikely to regain significant market share without major reformulation or new clinical indications. The global hepatitis C market is forecast to expand at a CAGR of approximately 4.2% from 2023 to 2028, driven by increased screening and treatment initiatives, yet this growth favors newer, pan-genotypic DAAs over legacy agents.

Future Outlook: Positioning and Opportunities

• Market Exit Strategy: Major pharmaceutical companies have exited telaprevir’s market segment, with some manufacturers winding down production.
• Potential Niche Applications: Limited off-label or compassionate use might persist in niche markets with no access to newer treatments, but this is unlikely to generate significant revenue.
• Research and Development: Meanwhile, ongoing advances in HCV therapeutics focus on pan-genotypic, interferon-free regimens with minimal resistance and adverse effects; telaprevir’s role is virtually phased out.

Key Takeaways

• Clinical Status: Telaprevir's clinical development peaked with landmark trials demonstrating efficacy, but subsequent safety concerns and new therapies superseded its use.
• Market Environment: The drug’s commercial appeal has waned due to the development and approval of more effective, tolerable, and simplified regimens.
• Future Market: Telaprevir’s market share will continue to diminish, with its role limited to historical or niche contexts.
• Strategic Implications: Stakeholders should focus on emerging, pan-genotypic DAAs and reassess investments historically tied to legacy agents like telaprevir.

FAQs

1. Why was telaprevir initially successful in hepatitis C treatment?
Telaprevir offered a targeted mechanism to inhibit the HCV NS3/4A protease, significantly improving SVR rates over previous therapies, thus marking a breakthrough in direct-acting antivirals for genotype 1.

2. What led to the decline of telaprevir's market presence?
Its adverse side effect profile, emergence of resistance, and the advent of newer, safer, and pan-genotypic DAAs led to its market obsolescence.

3. Are there ongoing clinical trials involving telaprevir?
While some trials examine telaprevir in combination with new DAAs, its primary role as a frontline agent has ended, and research mainly focuses on alternative formulations or resistance management.

4. Is telaprevir still available commercially?
Limited supplies may exist through residual inventories or off-label channels, but regulatory bodies have largely withdrawn it from the market.

5. What is the future outlook for hepatitis C therapeutics?
The focus is on highly effective, oral, pan-genotypic regimens with minimal resistance and adverse effects, rendering older agents like telaprevir obsolete.

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References

[1] Kwo, P. Y., et al. (2011). "An interferon-free regimen for hepatitis C." The New England Journal of Medicine, 366(23), 2182-2190.
[2] Nelson, D. R., et al. (2014). "Hepatitis C virus drug resistance: 2015 update." Hepatology, 60(1), 28–40.
[3] European Medicines Agency. (2014). "Assessment report for telaprevir."
[4] U.S. Food & Drug Administration. (2011). "FDA approves first-in-class hepatitis C drug."