Press Release Details

Preliminary SVR4 Data of 99 percent Announced on Phase 2b regimens containing ABT-493 and ABT-530

WATERTOWN, Mass.--(BUSINESS WIRE)--Apr. 8, 2015-- Enanta Pharmaceuticals, Inc. (NASDAQ:ENTA), a research and development-focused biotechnology company dedicated to creating small molecule drugs for viral infections and liver diseases, announced today abstracts of research on regimens containing either one of Enanta’s two protease inhibitors for hepatitis C virus (HCV) identified and developed in its ongoing collaboration with AbbVie, have been accepted for presentation at The International Liver Congress (ILC), which is the 50^th Annual Meeting of the European Association for the Study of the Liver (EASL) taking place in ViennaApril 22-26, 2015. Paritaprevir, Enanta’s lead protease inhibitor, is included in AbbVie’s HCV treatment regimens approved in the U.S. in late 2014 and in the E.U. in early 2015. ABT-493, the collaboration’s next-generation protease inhibitor currently in phase 2b clinical studies, is being developed by AbbVie in combination with ABT-530, AbbVie’s next generation NS5A inhibitor, for pan-genotypic treatment of HCV.

Enanta also announced that AbbVie reported preliminary results from a Phase 2b study (n=79) of ABT-493 and ABT-530 combination treatments in non-cirrhotic genotype 1 HCV patients receiving the ribavirin (RBV)-free, once-daily regimen for 12 weeks demonstrated a sustained virologic response rate at four weeks post treatment (SVR4) of 99 percent (n=78/79). These results announced for the first time today included both GT1a and GT1b, treatment-naïve and pegylated-interferon and RBV prior null responders. Patients across both study arms were randomized to receive ABT-493 (200mg) and either 120mg or 40mg of ABT-530. To date, the most common (>5 percent) adverse reactions were fatigue, headache, nausea, diarrhea and anxiety. Data from these Phase 2b studies of ABT-493 and ABT-530 combinations will not be presented at ILC 2015, but are expected to be released at future medical congresses. AbbVie’s ongoing development program investigating a pan-genotypic, RBV-free treatment regimen containing ABT-493 may allow for treatment durations of as little as 8 weeks.

The following list of paritaprevir-related and ABT-493-related e-poster, oral presentations and abstracts can now be viewed at the EASL website at www.easl.eu.

Oral Presentations:
Friday, April 24, 2015
4:15 - 4:30 p.m. CEST
#O057: LONG-TERM FOLLOW-UP OF TREATMENT-EMERGENT RESISTANCE-ASSOCIATED VARIANTS IN NS3, NS5A AND NS5B WITH PARITAPREVIR/R-, OMBITASVIR- AND DASABUVIR-BASED REGIMENS
Presenter: Preethi Krishnan

Saturday, April 25, 2015
08:30 - 08:45 a.m. CEST
#G13: OMBITASVIR/PARITAPREVIR/RITONAVIR FOR TREATMENT OF HCV GENOTYPE 1B IN JAPANESE PATIENTS WITH OR WITHOUT CIRRHOSIS: RESULTS FROM GIFT-I
Presenter: Ken Sato

Late Breakers Session
Saturday April 25, 2015
4:00 - 4:15 p.m. CEST
SAFETY OF OMBITASVIR/PARITAPREVIR/RITONAVIR PLUS DASABUVIR FOR TREATING HCV GT1 INFECTION IN PATIENTS WITH SEVERE RENAL IMPAIRMENT OR END-STAGE RENAL DISEASE: THE RUBY-I STUDY
Presenter: Paul Pockros

E-Poster Presentations:

ABT-493
P0715: STEADY-STATE PHARMACOKINETICS AND SAFETY OF COADMINISTRATION OF PAN-GENOTYPIC, DIRECT ACTING PROTEASE INHIBITOR, ABT-493 WITH PAN-GENOTYPIC NS5A INHIBITOR, ABT-530, IN HEALTHY ADULT SUBJECTS
Presenter: Chih-Wei Lin

P0855: PHARMACOKINETICS OF ABT-493 AND ABT-530 IS SIMILAR IN HEALTHY CAUCASIAN, CHINESE, AND JAPANESE ADULT SUBJECTS
Presenter: Tianli Wang

Paritaprevir

LP39: IMPLICATIONS OF BASELINE HCV RNA LEVEL AND INTRAPATIENT VIRAL LOAD VARIABILITY ON OBV/PTV/R + DSV 12-WEEK TREATMENT OUTCOMES
Presenter: Robert Brown

P0781: HIGH SVR RATES DESPITE MULTIPLE NEGATIVE PREDICTORS IN GENOTYPE 1 PATIENTS RECEIVING OMBITASVIR/PARITAPREVIR/R, DASABUVIR WITH OR WITHOUT RIBAVIRIN FOR 12 AND 24 WEEKS: INTEGRATED ANALYSIS OF SIX PHASE 3 TRIALS
Presenter: David Bernstein

P0806: THE VALUE OF SURVIVAL BENEFITS FROM TREATING HEPATITIS C AT DIFFERENT FIBROSIS STAGES WITH ALL-ORAL, INTERFERON-FREE THERAPY RELATIVE TO ‘WATCHFUL WAITING’
Presenter: Yuri Sanchez Gonzalez

P0808: IMPROVEMENT IN LIVER FUNCTION AND NON-INVASIVE ESTIMATES OF LIVER FIBROSIS 48 WEEKS AFTER TREATMENT WITH OMBITASVIR/PARITAPREVIR/R, DASABUVIR AND RIBAVIRIN IN HCV GENOTYPE 1 PATIENTS WITH CIRRHOSIS
Presenter: Heiner Wedemeyer

P0815: COST-EFFECTIVENESS OF TREATING DIFFERENT STAGES OF GENOTYPE 1 HEPATITIS C VIRUS (HCV) WITH ABBVIE 3D (ABT-450/RITONAVIR/OMBITASVIR AND DASABUVIR) +/- RIBAVIRIN COMPARED TO NO TREATMENT IN THE UNITED STATES
Presenter: Jennifer C. Samp

P0816: REDUCTION IN ANNUAL MEDICAL COSTS WITH EARLY TREATMENT OF HCV USING ABBVIE 3D (ABT-450/RITONAVIR/OMBITASVIR AND DASABUVIR) +/- RIBAVIRIN IN THE UNITED STATES
Presenter: Jennifer C. Samp

P0820: PHARMACOKINETICS OF PARITAPREVIR, OMBITASVIR, DASABUVIR, RITONAVIR AND RIBAVIRIN IN SUBJECTS WITH HCV GENOTYPE 1 INFECTION IN PHASE 3 STUDIES
Presenter: Sven Mensing, Amit Khatri

P0823: PHARMACOKINETICS OF PARITAPREVIR, OMBITASVIR, RITONAVIR AND RIBAVIRIN IN SUBJECTS WITH HCV GENOTYPE 4 INFECTION
Presenter: Dörthe Eckert

P0842: MALACHITE-I: PHASE 3B TRIAL OF OMBITASVIR/PARITAPREVIR/R AND DASABUVIR +/-RIBAVIRIN OR TELAPREVIR + PEGINTERFERON/RIBAVIRIN IN TREATMENT-NAÏVE ADULTS WITH HCV GENOTYPE 1
Presenter: Brian Conway

P0847: MALACHITE-II: PHASE 3B TRIAL OF OMBITASVIR/PARITAPREVIR/R AND DASABUVIR + RIBAVIRIN OR TELAPREVIR + PEGINTERFERON/RIBAVIRIN IN PEGINTERFERON/RIBAVIRIN TREATMENT-EXPERIENCED ADULTS WITH HCV GENOTYPE 1
Presenter: Gregory Dore

P0850: PERCENT OF SUBJECTS EXPERIENCING LIVER MORBIDITY OVER A LIFETIME HORIZON WITH ABBVIE 3D (ABT-450/RITONAVIR/OMBITASVIR AND DASABUVIR) VERSUS NO TREATMENT
Presenter: Jennifer C. Samp

P0856: OMBITASVIR/PARITAPREVIR/RITONAVIR AND DASABUVIR WITH RIBAVIRIN (RBV) HAS MILD IMPACT ON HEALTH-RELATED QUALITY OF LIFE (HRQOL) COMPARED WITH PLACEBO DURING 12-WEEK TREATMENT IN TREATMENT-EXPERIENCED ADULTS WITH CHRONIC HEPATITIS C (CHC)
Presenter: Yan Liu

P0873: OMBITASVIR/PARITAPREVIR/RITONAVIR AND DASABUVIR WITH RIBAVIRIN (RBV) HAS MINIMAL IMPACT ON HEALTH-RELATED QUALITY OF LIFE (HRQOL) COMPARED WITH PLACEBO DURING 12-WEEK TREATMENT IN TREATMENT-NAÏVE ADULTS WITH CHRONIC HEPATITIS C (CHC)
Presenter: Yan Liu

P0902: EXPOSURE-RESPONSE ANALYSES FOR EFFICACY (SVR12) FOR THE DIRECT ACTING ANTIVIRAL REGIMEN OF ABT-450/R, OMBITASVIR WITH DASABUVIR ± RIBAVIRIN IN SUBJECTS WITH HCV GENOTYPE 1 INFECTION
Presenter: Amit Khatri

P0905: NO SIGNIFICANT INTERACTION AMONG OMBITASVIR/PARITAPREVIR/RITONAVIR ± DASABUVIR AND SOFOSBUVIR
Presenter: Jennifer King

P0908: ADHERENCE TO OMBITASVIR/PARITAPREVIR/R, DASABUVIR, AND RIBAVIRIN IS >98% IN THE SAPPHIRE-I AND SAPPHIRE-II TRIALS
Presenter: Tarek Hassanein

P1245: PUBLIC HEALTH IMPACT OF HCV SCREENING AND TREATMENT IN THE FRENCH BABY-BOOMER POPULATION
Presenter: Olivier Ethgen

P1331: PHASE 3B STUDIES TO ASSESS LONG-TERM CLINICAL OUTCOMES IN HCV GT1-INFECTED PATIENTS TREATED WITH OMBITASVIR/PARITAPREVIR/RITONAVIR AND DASABUVIR WITH OR WITHOUT RIBAVIRIN
Presenter: Emily O. Dumas

P1345: A RANDOMIZED, OPEN-LABEL STUDY TO EVALUATE EFFICACY AND SAFETY OF OMBITASVIR/PARITAPREVIR/RITONAVIR CO-ADMINISTERED WITH RIBAVIRIN IN ADULTS WITH GENOTYPE 4 CHRONIC HEPATITIS C INFECTION AND CIRRHOSIS
Presenter: Tarik Asselah

P1351: AN OPEN-LABEL STUDY TO EVALUATE THE EFFICACY AND SAFETY OF CO-FORMULATED OMBITASVIR/PARITAPREVIR/RITONAVIR WITH RIBAVIRIN IN ADULTS WITH CHRONIC HCV GENOTYPE 4 INFECTION IN EGYPT
Presenter: Wahid Doss

Forward-Looking Statement Disclaimer

This press release contains forward-looking statements, including statements with respect to the prospects for AbbVie’s HCV treatment regimens containing ABT-493 for HCV. Statements that are not historical facts are based on our management’s current expectations, estimates, forecasts and projections about our business and the industry in which we operate and our management’s beliefs and assumptions. The statements contained in this release are not guarantees of future performance and involve certain risks, uncertainties and assumptions, which are difficult to predict. Therefore, actual outcomes and results may differ materially from what is expressed in such forward-looking statements. Important factors that may affect actual results include the efforts of AbbVie (our collaborator on ABT-493) to develop and obtain regulatory approvals and commercialize treatment regimens containing ABT-493; the development, regulatory and marketing efforts of others with respect to competitive HCV treatment regimens; regulatory and reimbursement actions affecting any ABT-493-containing regimens, any competitive regimens, or both; the level of market acceptance and the pricing and rate of reimbursement for any ABT-493-containing regimens; and other risk factors described or referred to in “Risk Factors” in Enanta’s most recent Form 10-K for the fiscal year ended September 30, 2014 and other periodic reports filed more recently with the Securities and Exchange Commission. Enanta cautions investors not to place undue reliance on the forward-looking statements contained in this release. These statements speak only as of the date of this release, and Enanta undertakes no obligation to update or revise these statements, except as may be required by law.

About Enanta

Enanta Pharmaceuticals is a research and development-focused biotechnology company that uses its robust chemistry-driven approach and drug discovery capabilities to create small molecule drugs for viral infections and liver diseases. Enanta is discovering, and in some cases developing, novel inhibitors designed for use against the hepatitis C virus (HCV). These inhibitors include members of the direct acting antiviral (DAA) inhibitor classes – protease (partnered with AbbVie), NS5A, and nucleotide polymerase – as well as a host-targeted antiviral (HTA) inhibitor class targeted against cyclophilin. Enanta’s lead protease inhibitor, paritaprevir, is part of AbbVie’s recently approved HCV treatment regimens. In addition, Enanta has a preclinical program in non-alcoholic steatohepatitis, or NASH, which is a condition that results in liver inflammation and damage caused by a buildup of fat in the liver.

Source: Enanta Pharmaceuticals, Inc.

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