ClinicalTrials.gg
CompletedNCT04019717Updated May 4, 2020

Study of AT-527 in Combination With Daclatasvir in Subjects With Hepatitis C Virus (HCV) Infection

A Phase 2 interventional study of AT-527 and Daclatasvir in Hepatitis C, Hepatitis C, Chronic and Chronic Hepatitis C, sponsored by Atea Pharmaceuticals, Inc.. Completed at 3 sites in 3 countries. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2020-05-04.

Primary conditionHepatitis C, ChronicRegistry: Hepatitis CReclassifiedWhy we changed it
Registry
Hepatitis C — the first condition term the registry derived for this study.
ClinicalTrials.gg
Hepatitis C, Chronic
Why
  1. The study's listed conditions name Hepatitis C, Chronic, a narrower term within Hepatitis C.
Confidence
High: the new condition is named in the study's own listed conditions. Of 351 hand-checked studies reclassified this way, 68% were exactly right and 84% in the right disease family; the registry's first term was right for 5% (measured 2026-10-21). How we classify →
Wrong?
Tell us the study's main condition →

Sponsored by Atea Pharmaceuticals, Inc. · Phase 2, Interventional, and Treatment

Phase
Phase 2
Study type
Interventional
Enrollment
10
Allocation
Non-randomized
Ages
18 Years to 65 Years
Sex
All
01

Study summary

The study will assess the safety and efficacy of AT-527 in combination with daclatasvir after 8 or 12 weeks of treatment.

02

Conditions studied

  • Hepatitis C
  • Hepatitis C, Chronic
  • Chronic Hepatitis C
  • Hepatitis C Virus Infection
  • HCV Infection

Browse trials for

03

In context

Hepatitis C, Chronic Reclassified

950 studies on the registry are indexed under Hepatitis C, Chronic; 8 are open to participants now.

This study's enrollment of 10 is below the median of 90 across 696 interventional studies indexed under Hepatitis C, Chronic.

Browse Hepatitis C, Chronic studies →

Lead sponsor

Atea Pharmaceuticals, Inc. is the lead sponsor of 33 studies on the registry; 1 is open to participants now.

Of its 25 completed or terminated interventional studies of FDA-regulated products, 4 (16%) have results posted.

Compared within Hepatitis C, Chronic, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Hepatitis C. The counts are of registry records indexed under each term, refreshed daily. How we classify →

04

Who can participate

Ages eligible
18 Years to 65 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • (BMI) of 18-35 kg/m2
  • Must agree to use protocol-specified methods of
  • Negative pregnancy test
  • genotype 1
  • Documented history compatible with chronic hepatitis C
  • HCV RNA ≥ 10,000 IU/mL at Screening.
  • Willing to comply with the study requirements and to provide written

Exclusion criteria

Exclusion Criteria:

  • Pregnant or breastfeeding
  • Infected with virus or
  • Abuse of alcohol or drugs
  • Prior exposure to any NS5A inhibitor
  • Cirrhosis
  • Use of other drugs within 30 days of dosing
  • Other medical conditions or to daclatasvir
Terms in these criteria, in plain language(9)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

BMI (body mass index)

Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.

What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

Hepatitis C tests

Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.

After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

Hepatitis B tests

Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.

Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.

HIV

The human immunodeficiency virus, which weakens the immune system.

Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

Clinically significant

Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.

Contraindication

A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.

05

Study design

Phase
Phase 2
Primary purpose
Treatment
Allocation
Non-randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
10 participants (actual)

Study arms

  • Experimental
    8 weeks

    Drug: AT-527 · Drug: Daclatasvir

  • Experimental
    12 weeks

    Drug: AT-527 · Drug: Daclatasvir

Interventions

  • DrugAT-527

    Nucleotide prodrug inhibitor of HCV nonstructural protein 5B (NS5B) polymerase

  • Inhibitor of HCV nonstructural protein 5A (NS5A)

06

What researchers measure

Primary outcomes

  1. Proportion of subjects achieving sustained virologic response (SVR)

    SVR defined as the HCV RNA \< lower limit of quantitation (LLOQ) at 12 weeks after end of treatment

    Time frame: 12 weeks after end of treatment

  2. Incidence of treatment-emergent adverse events

    Time frame: Through 4 weeks after end of treatment

07

Study locations

3 sites
  • Clinical Trial Site
    Antwerp, Belgium
  • Clinical Trial Site
    Phoenix, Mauritius
  • Clinical Trial Site
    Chisinau, Moldova, Republic of
08

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on May 4, 2020, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
09

Registry details

Key details

Study ID
NCT04019717
Responsible party
Sponsor
First posted
Jul 15, 2019
Start date
Jun 20, 2019
Primary completion
Jan 29, 2020
Completion
Mar 23, 2020
Last update
May 4, 2020

Study contacts

Xiao-Jian Zhou, PhD
study director · Atea Pharmaceuticals, Inc.

Oversight

FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in May 2020. You cannot join it, but the record below documents what was studied.

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